ALBERT

Beschreibung: The fluorescent properties of dissolved organic matter (DOM) have been used as natural tracers in various water systems. However, only few studies have focused on groundwater systems, specifically, on karst systems. The aim of this study was to develop the use of the DOM fluorescence signal as a natural tracer, considering the multiple compartments of a karst system. This method was applied to the Lez hydrosystem, which supplies the city of Montpellier with drinking water. The hydrodynamics and hydrochemistry of the spring were monitored beginning March 2006. The DOM fluorescence was measured by the excitation–emission matrix spectroscopy technique. The analysis of the total fluorescence signal confirms the efficiency of this tool to trace rapid infiltration flows. Moreover, the decomposition of the signal into different fluorophores complements the information provided by the total signal. Indeed, the fluorescence emitted by the humic compounds seems to be the ideal tool for identifying rapid infiltration flows. Nevertheless, the fluorescence of protein-like compounds is better correlated with the inflow of faecal bacteria at the outlet. This decomposition of the fluorescence signal is an interesting way to provide information on both the rapid infiltration flow as well as the vulnerability of the karst aquifers.

Beschreibung: Manned lunar exploration has recently attracted renewed interest. This includes the NASA Constellation program to return humans to the Moon by 2020, the ESA Aurora program which may use the Moon as a way station to prepare for major interplanetary exploration by 2025, and the PRC program to send a human to the Moon by 2030 and build a temporary manned lunar base by 2040. One of the problems demanding a solution is the stresses on the mechanical characteristics of the lunar regolith under the microgravity environment. The gravity on the Moon is about 1/6 that on Earth. The regolith is subject to very low confining stresses under a microgravity environment and the mechanical properties can change correspondingly. Because of the limited amount of lunar regolith brought back to Earth by the Apollo missions, a lunar regolith simulant was developed using silicon carbide to investigate the properties of the lunar regolith. Based on triaxial tests, this study analyzed the mechanical properties of the lunar regolith simulant at low stresses including the shear strength, peak strength and dilatation angle. The research results provide useful information on lunar regolith characteristics for astronauts returning to the Moon and for building a temporary manned lunar base.

Beschreibung: The vegetation community succession influences soil nutrient cycling, and this process is mediated by soil microorganisms in the forest ecosystem. A degraded succession series of karst forests were chosen in which vegetation community changed from deciduous broadleaved trees (FO) toward shrubs (SH), and shrubs–grasses (SHG) in the southwest China. Soil organic carbon (SOC), total nitrogen (TN), labile organic carbon (LOC), water extractable organic matter (WEOM), microbial biomass carbon and nitrogen (MBC and MBN), bacterial and fungal diversity, as well as soil enzyme activities were tested. The results showed that SOC, LOC, MBC, MBN, and enzyme activities declined with vegetation succession, with the relatively stronger decrease of microbial biomass and functions, whereas WEOM was higher in SHG than in other systems. In addition, soil bacterial and fungal composition in FO was different from both SH and SHG. Despite positive relationship with SOC, LOC, and TN ( p  〈 0.01), MBC, MBN appeared to be more significantly correlated to LOC than to SOC. It suggested that vegetation conversion resulted in significant changes in carbon fractions and bioavailability, furthermore, caused the change in soil microbial community and function in the forest ecosystem.

Beschreibung: The sinuosity factor (SF) is a critical value in karst systems in terms of estimating their hydrodynamic parameters including groundwater velocity, coefficient of dispersion, etc., through dye tracer experiments. SF has been used in a number of different dye tracer experiments in karstic systems to estimate a representative flow path. While knowing SF is crucially important in the estimation of hydrodynamic parameters, its calculation is associated with significant uncertainty due to the complexity of subsurface karstic features. And yet, only a few studies have discussed its uncertainties, which might lead some errors in estimation of hydrodynamic parameters from dye tracer experiment. In this study, dye tracer experiments were conducted in two consecutive years (2003 and 2004) representing low and high flow conditions in the Beyyayla sinkhole (Eskişehir, Turkey) where the flow path is well known. Uranine was used in experiments as a tracer and QTRACER computer program was used to determine the hydrodynamic properties of the Beyyayla karst system as well as to gain insights into the effects of SF from dye tracer experiments on estimated parameters. The results showed that the breakthrough curve follows a unimodal and a bimodal distribution in low and high flow conditions, respectively. These different distributions stem from the water transport mechanisms, where velocities were calculated as 58.2 and 93.6 m h −1 during low and high flow conditions observed in a spring emerging from the south side of the studied system. The results also show that the coefficient of dispersion, Reynolds number, and Peclet number increased and longitudinal dispersivity decreased with the higher flow rate. Furthermore, the estimated parameters did not vary with either the flow conditions or the tracer transit time, but they have shown some variations with SF. When SF was increased by 50 %, a change in these parameters was obtained in the range of 50–125 %.

Beschreibung: Arid regions in Asia are commonly characterized by rapidly growing populations with limited land resources and varying rainfall frequencies under climatic change. Despite being one of the most important environmental challenges in Asia, the changing aridity in this region, particularly due to large-scale land cover change, has not been well documented. In this study, we used rainfall data and a new land heterogeneity index to identify recent trend in land cover changes in the Asian arid regions. The result indicates a significant decreasing trend of barren lands and an increasing trend of vegetated lands. Although the potential land cover change is commonly believed to be strongly sensitive to rainfall change, such sensitivity has not been observed during the nine-year period (2001–2009) analyzed. Through the analyses of two separate periods (2001–2005 and 2005–2009), the sensitivity of rainfall to land cover change in arid regions is found to be dependent on the initial spatial heterogeneity of vegetated land cover. The approach used and the findings in this study represent an important step toward better understanding of large-scale land cover change in the Asian arid regions, and have the potential to predict future land cover change under various climate change scenarios.

Beschreibung: During 2003–2006, a pilot project of alternating water and CO 2 injection was performed on a limited part of the Upper Miocene sandstone oil reservoir of the Ivanić Field. During the test period oil and gas recovery was significantly increased. Additionally 4,440 m 3 of oil and 2.26 × 10 6  m 3 of gas were produced. It has initiated further modelling of sandstone reservoirs in the Ivanić Field in order to calculate volumes available for CO 2 injection for the purpose of increasing hydrocarbon production from depleted sandstone reservoirs in the entire Croatian part of the Pannonian Basin System. In the first phase, modelling was based on results of laboratory testing on the core samples. It considered applying analogies with world-known projects of CO 2 subsurface storage and its usage to enhance hydrocarbon production. In the second phase, reservoir variables were analysed by variograms and subsequently mapped in order to reach lithological heterogeneities and to determine reliable average values of reservoir volumes. Data on porosity, depth and reservoir thickness for the “Gamma 3” and the “Gamma 4” reservoirs, are mapped by the ordinary kriging technique. Calculated volume of CO 2 expressed at standard condition which can be injected in the main reservoirs of the Ivanić Field at near miscible conditions is above 15.5 billion m 3 .

Beschreibung: With this paper, we assess the present-day conductive thermal field of the Glueckstadt Graben in NW Germany that is characterized by large salt walls and diapirs structuring the graben fill. We use a finite element method to calculate the 3D steady-state conductive thermal field based on a lithosphere-scale 3D structural model that resolves the first-order structural characteristics of the graben and its underlying lithosphere. Model predictions are validated against measured temperatures in six deep wells. Our investigations show that the interaction of thickness distributions and thermal rock properties of the different geological layers is of major importance for the distribution of temperatures in the deep subsurface of the Glueckstadt Graben. However, the local temperatures may result from the superposed effects of different controlling factors. Especially, the upper sedimentary part of the model exhibits huge lateral temperature variations, which correlate spatially with the shape of the thermally highly conductive Permian salt layer. Variations in thickness and geometry of the salt cause two major effects, which provoke considerable lateral temperature variations for a given depth. (1) The “chimney effect” causes more efficient heat transport within salt diapirs. As a consequence positive thermal anomalies develop in the upper part and above salt structures, where the latter are covered by much less conductive sediments. In contrast, negative thermal anomalies are noticeable underneath salt structures. (2) The “thermal blanketing effect” is caused by thermally low conductive sediments that provoke the local storage of heat where these insulating sediments are present. The latter effect leads to both local and regional thermal anomalies. Locally, this translates to higher temperatures where salt margin synclines are filled with thick insulating clastic sediments. For the regional anomalies the cumulative insulating effects of the entire sediment fill results in a long-wavelength variation of temperatures in response to heat refraction effects caused by the contrast between insulating sediments and highly conductive crystalline crust. Finally, the longest wavelength of temperature variations is caused by the depth position of the isothermal lithosphere–asthenosphere boundary defining the regional variations of the overall geothermal gradient. We find that a conductive thermal model predicts observed temperatures reasonably well for five of the six available wells, whereas the steady-state conductive approach appears not to be valid for the sixth well.

Beschreibung: Ecosystem services are the basis of human living and development. Land use has significant effects on the ecosystem structure and functions, even its services. Using the remote sensing (RS), geographical information system and ecological economy theory, this paper analyzed land use changes of different eco-economic functional areas in Manas River Basin during the period 1958–2006 using different stage RS images. This paper selects the evaluation method obtained by Costanza et al. and Xie Gaodi, and the ecological sensitivity coefficient analysis, which analyzed the variation characteristics of eco-service values of different eco-economic functional areas. The results showed that the land use pattern has changed greatly from 1958 to 2006. The area of farmland and industrial area increased rapidly, while the forest area, grassland, water area and unutilized area decreased greatly. The total eco-service value of the river basin decreased from 3,529.64 US$ × 10 6 in 1958 to 2,559.88 US$ × 10 6 in 2006. There was 27.47 % net loss of 969.76 US$ × 10 6 . The eco-service values of various land use types in the study area were close to the regional real values and the results were credible. There existed apparent temporal and spatial changes in the eco-service values of different eco-economic functional areas, and this significant change in the eco-service values was driven by economic development. Consequently, in view of eco-economic characteristics and ecological issues of various eco-economic functional areas, relevant strategies of ecological conservation were proposed for enhancing the general eco-service value of the river basin and realizing the regional sustainable development. The ‘‘yuan’’ is Chinese money unit (¥), US$1 = ¥6.27 (yuan).

Beschreibung: Readily dispersible clay is the part of the clay fraction in soils that potentially disperses in water when a small amount of mechanical energy is applied to soil. Column and batch experiments were conducted to identify the effect of readily dispersible clay on the mobility of some metal ions in a disturbed soil sample. The clay fraction (〈0.002 mm) was separated from an alkaline Vertisol from the Nile River Delta. X-ray diffraction technique was used to identify minerals present in the clay fraction. Clay suspensions and deionized H 2 O solutions of Cd 2+ , Cu 2+ , and Zn 2+ were prepared and used as influents in soil columns. Adsorption capability of the studied soil among the three metal ions was investigated. The results showed high adsorption capacity of Cd 2+ , Cu 2+ , but not Zn 2+ for the studied soil. Cu 2+ was the highest adsorbed metal by soil and its sorption increased at small equilibrium concentrations compared with Cd 2+ and Zn 2+ . For the three studied metal ions, Langmuir model represented the best fit to the adsorption data. The concentration of Zn 2+ and Cd 2+ in leachates increased as the leaching solution volume increased, while Cu 2+ showed a homogeneous distribution throughout the soil column. According to DTPA extractable metals, Zn 2+ was appeared at greater depths than Cd 2+ , while Cu 2+ had homogeneous distribution through the soil column.

Beschreibung: Carboniferous black mudrocks with known petroleum potential occur throughout Northern Germany. However, despite numerous boreholes exploring for conventional hydrocarbons, the potential for shale gas resources remains uncertain. Therefore, an integrated investigation was conducted to elucidate the shale gas potential for three different Carboniferous facies incorporating baseline parameters from sedimentological and organic-geochemical analyses. Tournaisian–Namurian fine-grained rocks of the Culm-facies, with Type II + III kerogen were deposited in the basin center. TOC contents of up to 7 % occur in the Lower Alum Shale (3.6 % VRr) and up to 6 % in the Upper Alum Shale (4.4 % VRr). Bands of organic-rich black shales, reflecting sea-level variations controlled by global eustatic cycles, occur within the Tournaisian–Visean “Kohlenkalk” -facies north of the Rhenish Slate Mountains and in the Rügen island area. In both areas the organic matter is characterized by a kerogen Type II + III with TOC contents of up to 7 % and maturities of up to 4.2 and 1.8 % VRr, respectively. Black hemipelagites intercalated with coarser-grained silt- and sandstones occur in the Synorogenic Flysch Formation of the Namurian A along the southern basin margin. TOC contents vary from 0.5 to 2.0 % with Type III kerogen dominated organic matter and maturities of up to 2.5 % VRr. The baseline parameters presented in this paper indicate a shale gas potential for the sediments of the Culm-facies on the southern basin margin and of the “Kohlenkalk” -facies in the Rügen area.

Beschreibung: The characteristics of dissolved organic nitrogen (DON) in surface water from Beijing Olympic Forest Park (BOFP) were investigated in this study. Nanofiltration (NF) pretreatment procedure using two NF membranes (NF90 and NF270) was applied to increase the accuracy and precision of DON measurements in surface water samples with high dissolved inorganic nitrogen/total dissolved nitrogen (DIN/TDN) ratios. Compared to NF90, NF270 showed better performance in lowering the DIN/TDN ratio and retaining DOC in both the synthetic water and raw water samples. DON concentrations ranged from 0.01 to 0.83 mg N L −1 in water samples collected over four different months and showed a seasonal variation. The DON increased in summer due to the higher activity of decomposers on recent litterfall or because of a higher production of biomass in the surface water body. The molecular weight (MW) fractions of 〈3 kDa accounted for more than 50 % of the total DOC concentration and the fractions of 〈3 kDa contributed to more than 48 % of the total DON concentration. It could be concluded that most of the DON present in surface water of BOFP was composed of small molecules, which were mainly composed of monomers such as amino acids and urea, readily available for the uptake by phytoplankton and heterotrophic bacteria.

Beschreibung: The present study evaluated the effect of plant species on methane (CH 4 ) emission and microbial populations in three types of soil–plant systems. Results showed large variation of CH 4 flux rate ranging from 1.35 to 212.61 mg CH 4  m −2  h −1 . Emission peak of CH 4 occurred in July. No significant difference was found in the non-vegetation system spanning 2 years. Compared with non-vegetation, vegetation systems had much higher flux of CH 4 , and obvious seasonal variation was observed. The polyculture system planted with Zizania latifolia ( Z. latifolia ) and Phragmites australis ( P. australis ) released higher CH 4 fluxes than the mono system ( P. australis ), reflecting that Z. latifolia growth could simulate CH 4 emission. The fluorescence in situ hybridization (FISH) results support the characteristics of CH 4 fluxes. Much higher methanotrophs amount and lower methanogens amount from the mono system than those from the polyculture system was observed indicating that Z. latifolia growth may limit the oxygen transportation resulting in higher CH 4 emission. The polyculture system has the highest potential of CH 4 emission.

Beschreibung: Pannonibacter phragmitetus BB was utilized to treat hexavalent chromium [Cr(VI)] contaminated water. Cr(VI) concentration of the contaminated water (pH 10.85) was 534 mg/L. With the inoculum size ranging from 1 to 20 %, P. phragmitetus BB completely reduced Cr(VI) within 27 h when the initial medium concentration exceeded 20 g/L. The lag time of bio-reduction by Cr(VI)-induced cells was 24 h, which was longer than the non-Cr(VI)-induced cells. Under the agitation condition, an obvious bio-reduction lag phase existed and Cr(VI) was completely reduced within 24 h. However, the lag phase was not observed under the static condition, Cr(VI) was reduced continuously after inoculation and Cr(VI) was completely reduced after 27 h incubation. The main chromium components after Cr(VI) reduction were Cr(OH) 3 , Cr 2 O 3 and CrCl 3 . The results of this study are fundamentally significant to the application of P. phragmitetus BB in the treatment of Cr(VI) contaminated water.

Beschreibung: Research on the seepage deformation of saturated soft soil has resulted in many achievements based, mainly, on existing seepage-deformation control equations. In reality, however, these control equations and related parameters suffer from many problems. The conductivity coefficient in the seepage control equation and the consolidation coefficient in the consolidation equation clearly resemble each other in form. However, in existing regulations and practice, soil deformation is rarely calculated by substituting the conductivity coefficient obtained from field hydrogeological experiments for the consolidation coefficient. Similarly, seepage is seldom calculated by substituting the conductivity coefficient with the consolidation coefficient obtained from consolidation experiments. This can be attributed to the fact that the two coefficients have some obvious differences. Moreover, the settlement deformation of soil calculated using the existing seepage and consolidation models does not agree very well with the measured deformation. Also, the values calculated using different models usually deviate markedly. Research indicates that these problems derive from the fact that the seepage and consolidation equations are based on different concepts of elementary volume. This study proposes using two separate elementary volume concepts: deformation elementary volume and control elementary volume. The concepts are adopted for saturated soft soil and the results used to analyze the relationships and differences between the two concepts. Moreover, we developed a conceptual data model (CDM) for the water released from and the deformation of the saturated soil. The model discloses the differences between the consolidation and conductivity coefficients both in their physical significances and magnitudes. The inter-relationship between the two coefficients is also revealed. An analytical solution for the deformation and water released from saturated soft soil is deduced based on the CDM model and the relationship between the hydrogeological and consolidation deformation parameters is established. A physical test model for saturated soft soil under certain conditions is also designed to verify the analytical solution using a method of curve fitting. Seepage and deformation tests and case studies show that the parameters calculated using the consolidation model are in agreement with those obtained from the CDM seepage model based on the measured data for flux and settlement vs. time. Furthermore, the relationship between conductivity and consolidation coefficients is verified. The method suggested in this paper is generally applicable to problems involving the consolidation coefficient, volume compressibility, conductivity coefficient, hydraulic conductivity, and specific storage of saturated soft soil, etc. Thus, its potential applications are numerous.

Beschreibung: Geosynthetic clay liners (GCLs) have been widely used as a hydraulic barrier along with HDPE geomembrane (GM) in landfills. Both the internal and interface strengths of GCLs are very important for evaluating landfill stability. An improved simple shear apparatus used in this study does not force the shear failure to occur along a pre-determined plane. The composite specimens can fail along any interface or through shearing of the GCL internally. The displacement of each component of the specimen can also be measured during the tests. When non-woven geotextile side contacts textured GM (NWGT/GMX) and woven geotextile side contacts compacted clay layer (WGT/CCL) for a dry GCL, the failure interface can change from NWGT/GMX interface to WGT/CCL interface with the increases of the normal stresses. Conversely, when woven geotextile side contacts textured GM (WGT/GMX) and non-woven geotextile side contacts compacted clay layer (NWGT/CCL) for a dry GCL, the failure always occurs at the WGT/GMX interface for all applied normal stresses. The internal failure of the GCL did not occur when the normal stress increased up to 1,500 kPa for the GCL in dry condition.

Beschreibung: The effect of glucose, chicken manure, and filter mud on the ammonium and nitrate concentrations, ammonia-oxidizing bacterial community and bacterial community in latosolic red soils during the incubation of microcosms was investigated. The soil nitrate concentration was significantly lower in the glucose-treated soil than in the filter mud or chicken manure-treated soil from days 2 and 5 to 21 of incubation. The ammonia-oxidizing bacteria community composition, measured by terminal restriction fragment length polymorphism analysis, was different among the treatments 9 days after incubation, suggesting that the control soil without external fertilization had a low 283-bp ( Nitrosospira ) fragment relative abundance (27 %) compared with the glucose-treated (62 %), filter mud (73 %) and chicken manure (78 %) samples. Additionally, 491-bp fragments ( Nitrosomonas ) were detected in all the soil treatments except for the control soil, and 48-bp fragments (from different Nitrosomonas ) were detected in the chicken manure-treated soil. The bacterial community structure was markedly changed in the glucose-treated soil on day 9 and in the filter mud-treated soil on day 31, indicating that the effect of filter mud on the bacterial community is delayed compared to the effect of glucose. The chicken manure-treated soil showed less change, similar to that of the control soil. Glucose fertilization greatly increased the soil bacterial abundance and functional diversity; however, the chicken manure and filter mud did not stimulate soil bacterial activity on day 9. These results indicated that nitrification may have been somewhat suppressed in the glucose-treated soils, which was possibly related to the improving ammonia-oxidizing bacterial community, bacterial community and activity via the available carbon application. The filter manure and chicken manure treatments demonstrated fewer effects. These results suggest that organic carbon quality, e.g., increasing the available carbon, regulates the nitrification process and is beneficial to reducing soil nitrogen losses.

Beschreibung: Sediment samples collected from the West Port, the west coastal waters of Malaysia, were analyzed by standard methods to determine the degree of hydrocarbon contamination and identify the sources of polyaromatic hydrocarbons (PAHs). Concentrations of PAHs in the port sediments ranged from 100.3 to 3,446.9 μg/kg dw. The highest concentrations were observed in stations close to the coastline, locations affected by intensive shipping activities and industrial input. These were dominated by high-molecular-weight PAHs (4–6 rings). Source identification showed that PAHs originated mostly pyrogenically, from the combustion of fossil fuels, grass, wood, and coal or from petroleum combustion. Regarding ecological risk estimation, only station 7 was moderately polluted, the rest of the stations suffered rare or slight adverse biological effects with PAH exposure in surface sediment, suggesting that PAHs are not considered as contaminants of concern in the West Port.

Beschreibung: Saline water intrusion is degrading water quality in the channelized coastal wetlands of the southern Albemarle estuarine system (AES). The source, transport and fate of the saline water in the southern AES was determined by monitoring specific conductivity and water levels in small artificial channels, the Alligator River, the Alligator–Pungo Canal and the groundwater system for ~12 months. Results indicate that water levels are affected by wind tides which trigger the movement of saline water into the interior of the wetlands via the small canals. The wind tides are mostly driven by episodic southerly winds pushing saline water into the canal network and the groundwater regime proximal to the Alligator River. The saline waters persist in the canals as long as the wind tide events last. Specific conductivities from canals and groundwater are shown to be unexpectedly higher closer to the source of the Alligator River than toward the Albemarle Sound, suggesting that the large Alligator–Pungo Canal facilitates the northward migration of saline water from the Pamlico Sound to the Alligator River. Overwash and reversals in the flow directions between groundwater and surface water bodies suggest that saline water that is present during wind tide events may migrate into the groundwater system from surface water bodies. The results of this study reveal that whereas the large Alligator–Pungo Canal channels saline water to the AES, small artificial channels may also play significant roles in degrading water quality in the interior of channelized coastal wetlands.

Beschreibung: The presence of coarse-grained sediment can potentially reduce the effectiveness of conventional sampling methods in recovering fluvial sediments. A modification to freeze-core technology was used to collect fine to coarse sands, silts, and clays in fluvial deposits that contain significant amounts of gravels, cobbles, and boulders for the purpose of characterizing the extent of heavy metal contamination. This modification uses either a 2.5 or 2.9 cm diameter by 30-cm- long finned mechanical or hand-driven samplers. The sediment is frozen to the outside of the sampler by injecting liquid CO 2 into the sampler. The fins protect the sample from coarse material upon removal. Field testing and laboratory testing of the method were completed to establish a methodology and assess possible cross contamination of the sediment layers during the driving of the sampler. The results indicated that this method is effective for recovering non-cohesive sediment samples at depths up to 6 m for the purpose of characterizing the extent of heavy metal contamination.

Beschreibung: Geochemical, mineralogical and textural analyses were carried out in core sediments off Adyar estuary, Bay of Bengal, India to record the contamination trend from urban and industrial activities during the historical past. Quartz, feldspar, kaolinite, chlorite and illite were the main lithogenic and clay minerals; carbonate was the predominant biogenic mineral. Trace metals (Fe, Al, Cu, Cr, Ni, Pb and Zn) indicate more enrichment in the surface sediment layers due to recent anthropogenic activities. The mean anthropogenic factor (AF) values for trace metals in core sediments decreased in the following order: Cr 〉 Ni 〉 Zn 〉 Cu 〉 Pb. The pollution load index (PLI) values in Adyar core sediments ranged from 1 to 1.25 with an average of 1.07. Based on AF, PLI, and sediment quality guidelines values for trace metals, significant metal enrichment and ecological risk were obtained in upper-most sediment layer. Multivariate statistical methods such as correlation matrix, principal component analysis and cluster analysis were carried out to find the relationships among the texture size, metals and minerals. The pollution of Adyar estuarine sediments was started in the 1960s, responding to the rapid economic development in Chennai coastal and Adyar estuarine region in the last five decades. Despite these high concentrations in the upper layer, development and expansion of industries are still continuing. The stricter regulations for the discharge and remediation of sediments are urgent for the conservation of environments and human health.

Beschreibung: Short duration rainfall data are required for certain hydrological risk assessments. However, short timescale rainfall intensity records are still scarce due to the high cost and low reliability of the monitoring systems. One way to solve this problem is by disaggregating rainfall data using stochastic methods. This study used the Bartlett Lewis Rectangular Pulse model to disaggregate daily rainfall into hourly rainfall for ten stations in the central region of Peninsular Malaysia. The performance of the model was evaluated on its ability to reproduce statistical properties, namely the mean and standard deviation, derived from the historical records over the disaggregated rainfall. The disaggregation of daily to hourly rainfall produced daily and hourly means that closely matched the historical records. However, the standard deviations of the disaggregated daily rainfall were lower than the historical values. Despite the significant differences in the standard deviation, both data series exhibit similar patterns and the model adequately preserved the trends of all the statistical properties used in evaluating its performance.

Beschreibung: The Gavbast karstic aquifer located in southern Iran is in direct contact with an exposed salt diapir. To assess the influence of the diapir on the quality of groundwater in the karstic aquifer, electrical conductivity, total dissolved solids, flow rate, temperature and major ion concentrations were measured at 57 sampling sites, including springs, surface waters and wells. A conceptual model of groundwater flow is proposed for the Gavbast karstic aquifer based on the geological setting, water budget, local base of erosion, and hydrochemistry of the sampling sites. The model suggests two subbasins in the Gavbast Anticline draining into two distinct discharging alluvial sections. Unexpectedly, groundwater discharging from the carbonate Gavbast aquifer is saline or brackish and water is of chloride type. The study indicates that the source of salinity of the Gavbast aquifers is infiltration of surface diapir-derived brine into the aquifer. The contribution of the diapir brine in the Gavbast karst aquifer is calculated about 4 L/s, using chloride mass balance. Construction of salt basins to evaporate brine discharging from the diapir springs is proposed to reduce the salinity of karst water. A row of strategically placed wells in the Gavbast karst aquifer would potentially exploit large volumes of fresh groundwater before it is contaminated by the salt. Such low-cost remediation should allow the agricultural exploitation of 40 km 2 of currently barren land.

Beschreibung: The enrichment characteristics and risk of heavy metals were studied in the sediments of Liucha River in Chao Lake Valley, where agricultural intensification has developed rapidly since the 1980s. The results revealed that Cd, Pb and Zn showed the lowest levels in the upper reaches and peak values in the lower reaches, increasing from 0.064, 7.75 and 59.75 mg/kg to 0.176, 12.33 and 96.82 mg/kg on average, respectively. Enrichment factor (EF) analysis showed that the EF values of Cd, Pb and Zn (maximum 4.76, 2.51 and 2.74, respectively) all increased from the upper reaches to the lower reaches (〉1.5), while correlation analysis and cluster analysis showed that they primarily originated from the extensive use of phosphate fertilizer. In addition, the comprehensive potential ecological risk due to Cd, Cr, Cu, Ni, Pb and Zn in the sediments showed low degree, but Cd showed moderate and high risk at some sites. Therefore, heavy metal pollution due to agricultural intensification in the agricultural regions of Chao Lake Valley should be given great attention during management of the water environment.

Beschreibung: The biodegradation of various wastewater-derived organic trace pollutants occurring in different aquatic compartments of the environment was previously reported to be influenced by the prevailing redox conditions. However, comparative studies on the redox-dependent degradation behavior of organic trace pollutants are scarce. The objective of the study presented herein, was to compile and evaluate data from several comparable previous tank experiments, thus, providing an overview on the redox-dependent removal of a total of 27 wastewater-derived trace compounds, including phenazone type compounds, antimicrobials, ß-blockers, psychoactive drugs and sulfonamides. Removal rate constants were fitted assuming first-order degradation kinetics. Six compounds were identified to be removed solely under oxic, three compounds solely under anoxic conditions. Others persisted under all experimental conditions, while some were removed under both oxic and anoxic conditions.

Beschreibung: Water resources in northern Cameroon have continuously been reducing over the past years. Many studies have suggested two principal causes: (1) human activities such as poor farming practices, unsustainable use of water resources, increased demand of water, deforestation, land-use change, etc., (2) human-induced climate change. Northern Cameroon in this study includes: the Adamawa, North and Far North regions located closer to the Sahel regions of Africa. These regions are already water stressed because of their location and any further change in climate with rising temperature would impact water resource either positively or negatively. Time series analysis and a 12-month standardized precipitation index (SPI12) with digital data between 1957 and 2006 were used to investigate the variation of water resources in northern Cameroon. Results obtained varies between the different regions with an increased annual trend in temperature and precipitation for Ngaoundere (Adamawa region) and Garoua (north region), whereas Maroua (far north region) had a decreased annual trend in both precipitation and temperature. Further variability results obtained from a SPI12 show that wetter period out number drought period in all three regions. The study concluded that water resources vary with the changing climatic condition and the severity of the impact varies from region to region. Furthermore, water deficiency in northern Cameroon might not be due to climate change. The reasons might be a combination of poor water management and other factors such population growth, the environmental condition, etc.

Beschreibung: Twenty groundwater samples were collected from Enugu metropolis over two seasonal periods in order to characterize the groundwater and to determine its quality for domestic and irrigation purposes. The results show that groundwater of the area is strongly acidic to slightly alkaline in nature and varied from “soft water” to “moderately hard” water type. The major ionic trend is in the order Cl −  〉 Na +  〉 HCO 3 −  〉 K +  〉 Mg 2+  〉 Ca 2+  〉 SO 4 2− and Mg 2+  〉 Cl −  〉 Na +  〉 K +  〉 Ca 2+  〉 HCO 3 −  〉 SO 4 2− in abundance for dry and rainy seasons, respectively. The results also reveal that there is an increase in trend of the ionic concentrations during the dry season, which arises from weathering of the host rocks and anthropogenic activities. Two hydrochemical facies were identified, namely, Na + –K + –Cl − –SO 4 2− and Ca 2+ –Mg 2+ –Cl − –SO 4 2− , with Na + –K + –Cl − –SO 4 2− as the dominant facies for the two seasons. Groundwater quality ranges from “very poor water” to “good water” and “water unsuitable for drinking purposes” to “good water” for the dry season and rainy season investigations, respectively. The groundwater is suitable for irrigation purposes for the two seasons.

Beschreibung: The objective of this work was to study sorption–desorption and/or precipitation–dissolution processes of Hg(II) compounds considering an eventual contact of soils with Hg-bearing wastes. In addition, this study contributes new data about Hg(II) chemistry in alkaline systems. Saline and alkaline soils with low organic matter (〈1 %) and high clay content (60–70 %) were obtained near a chlor-alkali plant. Batch techniques were used to perform the experiments using 0.1 M NaNO 3 solutions. Total Hg(II) concentrations ranged from 6.2 × 10 −8 to 6.3 × 10 −3  M. Sorption of Hg(II) was evaluated at two concentration ranges: (a) 6.2 × 10 −8 to 1.1 × 10 −4  M, and (b) 6.4 × 10 −4 to 6.3 × 10 −3  M. At low Hg(II) concentrations, adsorption occurred with a maximum sorption capacity ranging from 4 to 5 mmol/kg. At high Hg(II) concentrations, sorption–precipitation reactions occurred and maximum sorption capacity ranged from 17 to 31 mmol/kg. The distribution of Hg(II) hydrolysis products showed that Hg(OH) 2 was the predominant species under soil conditions. According to sorption experiments, X-ray diffraction and chemical speciation modelling, the presence of Hg(OH) 2 in the interlayer of the interstratified clay minerals can be proposed. Hg(OH) 2 was partially desorbed by repeated equilibrations in 0.1 M NaNO 3 solution. Desorption ranged from 0.1 to 0.9 mmol/kg for soils treated with 5.8 × 10 −5  M Hg(II), whereas 2.1–3.8 mmol/kg was desorbed from soils treated with 6.3 × 10 −3  M Hg(II). Formation of soluble Hg(II) complexes was limited by low organic matter content, whereas neutral Hg(OH) 2 was retained by adsorption on clay mineral surfaces.

Beschreibung: Seawater intrusion is a major threat to the rapidly depleting groundwater resources in the coastal areas of India. Groundwater-based irrigation, significant industrial development and rapid urbanization are some of the key contributors exacerbating the stress on groundwater resources. Vulnerability to seawater intrusion in the Ramanathapuram district of Eastern India is assessed here utilizing the GALDIT method, for a period of 10 years (2001–2010). Results revealed a drastic increase in percent area coverage under moderate vulnerability, from 19.5 to 53.88 %, between the years 2001 and 2010. On the contrary, areas classified as highly vulnerable underwent minor changes over the span of the study. Vulnerability of the study area was also analyzed for the year 2050 considering an average global mean sea level rise of 3.1 mm/year. Results from the analysis for the year 2050 showed that, almost, the entire study area (~97 %) was classified under moderate vulnerability. As a remedial measure to this imminent threat, favorable zones for artificial recharge were delineated on the basis of overlay analysis with weightage values for important controlling factors. Subsequently, the quantity of artificial recharge required to inhibit the intrusion of seawater, at specified favorable zones were estimated to be 674.87, 599.18 and 1,450.66 m 3 /year.

Beschreibung: Agricultural nonpoint source (NPS) pollution at the Three Gorges reservoir area in China has been increasingly recognized as a threat to aquatic environment in recent years due to the serious eutrophication problem. Adsorbed NPS pollution is one of the major forms of NPS pollution in mountainous regions, the essential of the adsorbed NPS pollution is soil loss. Thus, simple, highly sensitive and continuous methods are required to simulate and quantify sediments yield at watershed scales. It is imperative to construct an integrated model to estimate the sediment yield and adsorbed NPS pollution load. According to the characteristics of climate, hydrology, topography, geology, geomorphology and land use types in Three Gorges reservoir area, a GIS-based dynamic-integrated-distributed model of annual adsorbed NPS load was presented in view of impacts of the rainfall intensity, sediment delivery ratio (SDR) and land management, where the temporally dynamic-continuous model of annual sediment yield was established by modifying the revised Universal Soil Loss Equation (RUSLE), and the spatially integrated-distributed model of annual adsorbed NPS load was then developed via the correlation between sediment yield and adsorbed NPS load. Furthermore, a case study of the Jialing River basin in China was applied to validate the integrated model, the dynamic-distributed coupling among GIS technology, sediment yield model, and adsorbed NPS load model was achieved successfully. The simulation results demonstrate the following: (1) runoff and sediment are influenced greatly by rainfall intensity, SDR and vegetation cover; rainfall and land management show high sensitivities to the integrated model; the average annual adsorbed TN and TP pollution loads from 2006 to 2010 decreased by 76 and 74 % compared with the previous treatment (1990), respectively. (2) Spatio-temporal variations of adsorbed NPS nitrogen and phosphorus load are mainly related to different land use types and the background level of nutriments in topsoil; different land use types have different contribution rates; the largest contribution rates of adsorbed total nitrogen (TN, 58.9 %) and total phosphorus (TP, 53 %) loads are both from the dryland cropland. (3) The identification of critical source areas can help to implement the prevention and control measures aiming at the reduction of water environmental pollution. These results will provide useful and valuable information for decision makers and planners to take sustainable land use management and soil conservation measures for the control of sediment pollution in the Three Gorges reservoir area. The application of this model in the catchment shows that the integrated model may be used as a major tool to assess sediment yield risks and adsorbed NPS pollution load at mountainous watersheds.

Beschreibung: Lakes on the Qinghai-Tibet Plateau (QTP) are of particular interest to researchers because of their unusual high concentrations of lithium (Li), boron (B), and potassium (K). Kurnakovite, a member of the inderite group, is well-distributed on the QTP, however, the geochemical mechanisms of kurnakovite transformation requires further identification and clarification. This study aims to elucidate the geochemical mechanisms of kurnakovite deposits on the QTP from chloropinnoite dissolution using chemical kinetic and spectroscopic techniques. The new borate, chloropinnoite 2MgO · 2B 2 O 3  · MgCl 2  · 14H 2 O, was obtained from the natural concentrated salt lake brine on the QTP. The kinetics of chloropinnoite dissolved in 4.5 % (wt%) boric acid solution at 303, 313, and 323 K were investigated. The characterization of the phase transitions and the kinetics were carried out by chemical titration analysis, X-ray powder diffraction spectrometry, Fourier Transform Infrared (FT-IR), and Raman spectrometry. The results demonstrate that similar kinetic processes occur at all three temperatures and can be divided into dissolution, supersaturation, and precipitation, according to three distinct kinetic curves. Kurnakovite was the final phase transition (terminal secondary mineral) within the chloropinnoite-boric acid solution. The dissolution rate of chloropinnoite (the dissolution stage) could be described by second order pseudo-homogeneous reaction model. According to the spectroscopy data, geochemical mechanism of kurnakovite was identified. The new geochemical hypothesis well explains the geochemical mechanism of kurnakovite minerals on the QTP.

Beschreibung: Soil radon ( 222 Rn) has been monitored during winter months under cool-temperate deciduous stands of different surface geology in Tomakomai and in Sapporo, Hokkaido, Japan. Radon level was lower in Tomakomai of immature soil of porous volcanic ash emitted from an active volcano (Mt. Tarumae), compared with those in Sapporo of alluvial sediments. In Tomakomai, mean value of the 222 Rn activity concentration was higher in winter (570 Bq m −3 ) than in summer (350 Bq m −3 ) at a depth of 1 m, which is consistent with the results in cold and dry winter reported in the literature. In contrast, soil radon decreasing with decreasing soil temperature from mid-September (5.0 kBq m −3 ) remained low (2.6 kBq m −3 ) under persistent snow in Sapporo, which had already been observed in the same location. Measurements of the activity concentrations of 222 Rn in snow and in snow air as well as in soil air indicate that the small amount of 222 Rn is released from the ground surface to the overlying snowpack with a 222 Rn flux density of 0.4 mBq m −2  s −1 under thick snow cover in Sapporo.

Beschreibung: In the Three Gorges of China, there are frequent landslides, and the potential risk of landslides is tremendous. An efficient and accurate method of generating landslide susceptibility maps is very important to mitigate the loss of lives and properties caused by these landslides. This paper presents landslide susceptibility mapping on the Zigui-Badong of the Three Gorges, using rough sets and back-propagation neural networks (BPNNs). Landslide locations were obtained from a landslide inventory map, supported by field surveys. Twenty-two landslide-related factors were extracted from the 1:10,000-scale topographic maps, 1:50,000-scale geological maps, Landsat ETM + satellite images with a spatial resolution of 28.5 m, and HJ-A satellite images with a spatial resolution of 30 m. Twelve key environmental factors were selected as independent variables using the rough set and correlation coefficient analysis, including elevation, slope, profile curvature, catchment aspect, catchment height, distance from drainage, engineering rock group, distance from faults, slope structure, land cover, topographic wetness index, and normalized difference vegetation index. The initial, three-layered, and four-layered BPNN were trained and then used to map landslide susceptibility, respectively. To evaluate the models, the susceptibility maps were validated by comparing with the existing landslide locations according to the area under the curve. The four-layered BPNN outperforms the other two models with the best accuracy of 91.53 %. Approximately 91.37 % of landslides were classified as high and very high landslide-prone areas. The validation results show sufficient agreement between the obtained susceptibility maps and the existing landslide locations.

Beschreibung: Hydrothermally altered bedrock in the Silverton mining area, southwest Colorado, USA, contains sulfide minerals that weather to produce acidic and metal-rich leachate that is toxic to aquatic life. This study utilized a geographic information system (GIS) and statistical approach to identify watershed-scale geologic variables in the Silverton area that influence water quality. GIS analysis of mineral maps produced using remote sensing datasets including Landsat Thematic Mapper, advanced spaceborne thermal emission and reflection radiometer, and a hybrid airborne visible infrared imaging spectrometer and field-based product enabled areas of alteration to be quantified. Correlations between water quality signatures determined at watershed outlets, and alteration types intersecting both total watershed areas and GIS-buffered areas along streams were tested using linear regression analysis. Despite remote sensing datasets having varying watershed area coverage due to vegetation cover and differing mineral mapping capabilities, each dataset was useful for delineating acid-generating bedrock. Areas of quartz–sericite–pyrite mapped by AVIRIS have the highest correlations with acidic surface water and elevated iron and aluminum concentrations. Alkalinity was only correlated with area of acid neutralizing, propylitically altered bedrock containing calcite and chlorite mapped by AVIRIS. Total watershed area of acid-generating bedrock is more significantly correlated with acidic and metal-rich surface water when compared with acid-generating bedrock intersected by GIS-buffered areas along streams. This methodology could be useful in assessing the possible effects that alteration type area has in either generating or neutralizing acidity in unmined watersheds and in areas where new mining is planned.

Beschreibung: The aim of this study was to evaluate total mercury concentration and its lithogenic and exogenic fractions in some calcareous soils of western Iran, where water contamination and bioaccumulation of mercury have been reported in the bottomland’s reservoir. In particular, we investigated soil physico-chemical properties and weathering conditions related to lithogenic and exogenic fractions of mercury for two groups of calcareous soils with a known comparative pedological evolution and weathering condition that was evident in the presence or absence of underlying layers of accumulated clay. Our results showed that the total mercury content of the studied soils ranged from 45.40 to 830.36 with a mean of 486.81 μg kg −1 . Furthermore, calculation of mercury fractions revealed that lithogenic and exogenic fractions vary slightly according to the three reference elements (Fe, U and Nb) used in the calculations for the two groups of studied soils. The results also illustrated that most of the mercury content is of exogenic origin; therefore, total mercury variations are closely related to the content of exogenic mercury, while the lithogenic fraction exhibited no relationship with total mercury concentration. Moreover, application of the weathering indexes of Parker and the CaO/ZrO 2 molar ratio supported the dependence of lithogenic mercury accumulation on weathering intensity in the studied calcareous soils. However, the significance of this relationship is stronger for more weathered calcareous soils; in such cases, fine-particle fractions are more developed, which encourages carrier phases such as organic materials and iron oxyhydroxides to become involved in more efficient fixation of mercury. Nevertheless, the formation of underlying layers of accumulated clay, i.e. argillic horizons, may restrain fixation of exogenic mercury by limiting its atmospheric input.

Beschreibung: Dar es Salaam Quaternary coastal aquifer is a major source of water supply in Dar es Salaam City used for domestic, agricultural, and industrial uses. However, groundwater overdraft and contamination are the major problems affecting the aquifer system. This study aims to define the principal hydrogeochemical processes controlling groundwater quality in the coastal strip of Dar es Salaam and to investigate whether the threats of seawater intrusion and pollution are influencing groundwater quality. Major cations and anions analysed in 134 groundwater samples reveal that groundwater is mainly affected by four factors: dissolution of calcite and dolomite, weathering of silicate minerals, seawater intrusion due to aquifer overexploitation, and nitrate pollution mainly caused by the use of pit latrines and septic tanks. High enrichment of Na + and Cl − near the coast gives an indication of seawater intrusion into the aquifer as also supported from the Na–Cl signature on the Piper diagram. The boreholes close to the coast have much higher Na/Cl molar ratios than the boreholes located further inland. The dissolution of calcite and dolomite in recharge areas results in Ca–HCO 3 and Ca–Mg–HCO 3 groundwater types. Further along flow paths, Ca 2+ and Na + ion exchange causes groundwater evolution to Na–HCO 3 type. From the PHREEQC simulation model, it appears that groundwater is undersaturated to slightly oversaturated with respect to the calcite and dolomite minerals. The results of this study provide important information required for the protection of the aquifer system.

Beschreibung: This study focused on nitritation reactions for the removal of highly concentrated nitrogen from water recycled by a MWTP (Municipal Wastewater Treatment Plant) for the preparation of effluent standards which will be strengthened. To examine the changes that occur during a nitritation reaction with a variety of SRT operations when inducing a stable nitritation reaction, a reactor was operated on a laboratory scale in this study. Digestion tank supernatant flowed into a laboratory-scale reactor and organic matter in the effluent under various operation conditions was classified into four types according to ASM standards using the test known as the OUR (Oxygen Uptake Rate)-test. Most organic matter in the digestion tank supernatant appeared to consist of mainly the S I component out of non-biodegradable organic matter. During the operation period of the effluent in the laboratory-scale reactor, if a nitritation reaction occurs in a stable manner, most biodegradable organic matter is removed, consisting of mainly the S I component, like the influent. Particularly, nitrogen was removed after the S S was removed from the organic matters. Moreover, through a multiple correlation analysis between the operation results from a laboratory-scale reaction bath and the organic composition of the effluent, a method to predict the organic composition of effluents that relies on the operation result of the effluent is proposed.

Beschreibung: The aim of this study was to evaluate the release kinetics, speciation, and fractionation of boron (B) in some calcareous soils of western Iran. Ten surface soil samples were incubated with 100 mg B kg −1 for a week at field capacity moisture. After air drying of samples, the trend of B release was experimented using sequential extraction with 10 mM CaCl 2 . B speciation in soil solution was calculated for the first and the last steps of extraction by the visual MINTEQ program. The distribution of B among five fractions including exchangeable (F1), specially adsorbed (F2), bound by Fe–Mn oxides (F3), organically bound (F4) and residual (F5), was determined in control and spiked soils. The results indicated that the release rates were initially rapid followed by a slower reaction and the main proportion of the added B was extracted by CaCl 2 . The release kinetics of B was described well with Elovich, parabolic diffusion, power function, and first-order equations. The speciation results revealed that the uncharged boric acid (H 3 BO 3 0 ) was the dominant species in soil solutions. In control soils, B concentration in different fractions decreased in the following order: F5 〉 F1 〉 F2 〉 F3 〉 F4. In spiked soils, however, the largest and the smallest fractions were exchangeable and residual, respectively. This implies that B transformation from soluble to less mobile and non-labile forms is not a rapid process and requires more than a week. The significant relationship observed between kinetic parameters of power and parabolic equations and organically bound B fraction and OM content indicated that organic matter played an important role in B adsorption and release in calcareous soils.

Beschreibung: Changes in the stability of slopes reinforced with piles involve a complex interaction process between piles, soil, hydrogeological conditions and the engineering geological environment. Correlation analysis between each influencing factor will contribute to a better overall understanding of the main influencing factors. This is of great significance for disaster prevention and the optimization of soil slopes reinforced with piles. The 17 factors influencing the stability of soil slopes reinforced with piles were analyzed in this study, and the weighting of each influencing factor was determined using the analytic hierarchy process along with the experiences of various experts and the author’s experience. The results showed that: (1) soil rheological characteristics and physical and mechanical soil properties have the maximum weighting on the stability of soil slopes reinforced with piles; that is, they are the most important factors influencing the stability of soil slopes reinforced with piles; (2) embedded pile depth or pile anchoring depth and the pile position have the second greatest weighting; (3) rainfall, pile sectional dimensions and pile spacing, are also important factors. Each of these factors was not weighted less than 0.059.

Beschreibung: The water quality of the Vacacaí River was assessed at different sites in the period between winter 2005 and autumn 2006. All samples were analyzed for 52 elements (Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, Li, Be, Mg, Al, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, Ga, As, Se, Rb, Sr, Ag, Cd, In, Cs, Ba, Tl, Pb, Bi, U, Na, K, Hg, B, Mo, Sn, Te, Ti), temperature, pH, ammonia, and alkalinity levels. Water from the Vacacaí River ranged from slightly acidic to alkaline. No difference was observed in the chemical composition at different sites of the Vacacaí River. Levels of Ba, Ca, Sr and Mg increase in the dry seasons and reach their highest concentrations in autumn; Be and U decrease in the dry season and reach their highest concentration in spring. Al, Fe, Cr, Ni, Th, U Mn, Ca and Mg are highly positively related, indicating a common origin. Se and Cu are probably from anthropogenic source, from the rice crops of the margins of the river. Waterborne Al and Fe levels were above the desirable level for drinking water at all sites during all seasons. These results demonstrate the need for constant monitoring of water parameters, which is crucial to ensure water quality for the population of this region.

Beschreibung: Disasters caused by events such as earthquake, flooding, rock falls, landslides are often encountered. However, generally, the reasons for the destructive and devastating effects of these nature events are that settlement locations were chosen without site investigation studies, or that available studies were inadequate. Such inadequacies in the field are related to inappropriate settlement location and the resulting damage caused by rock falls. This study evaluated rockfall risk in a settlement that developed in a similar manner. The study was carried out in Boğaziçi village of Kemah (Erzincan/Turkey), which is located in a very important tectonic zone. The study site is located on the lower sections of an area with very steep cliffs and 50–75° slopes. This cliff, which is the source of rockfalls, has a slope dip of approximately 90°. The cliff comprises 25–30 m high, fractured and cracked basaltic volcanic mass. To determine block size in the study area, scanline survey measurements and block size measurements were performed on blocks that loosened and fell from the cliff face. It was found that block sizes reached 6 m 3 . Rockfall analyses were performed along the selected profiles using the Rockfall V.4.0 software. Kinetic energy, bounce height, horizontal location of rock end-points, and velocity of the rocks along each section were evaluated separately for each profile. This data were used to produce distribution maps for each profile and the settlement was evaluated in terms of rockfall risk. The results indicate that the study area was at risk of future rockfalls and that it would be appropriate to relocate one part of the settlement.

Beschreibung: The crosslinking reaction caused by blending different biopolymers and/or adding a crosslinking agent to biopolymers was studied. The rate of crosslinking reaction was estimated with weight swelling ratio (WSR), viscosity, and biodegradability. The crosslinked material from blending two biopolymers or mixing a crosslinking agent with a mixture of two biopolymers showed a polymeric volume change, a high microbial resistance even after 80 days, and a viscosity increased because of chemical functional groups to form extensive intra- and interpenetrating polymer networks (IPNs). The organized IPN is a base block in building a three-dimensional (3-D) crosslinked biopolymer structure. This 3-D structure can be utilized in the environmental and geotechnical applications such as an environmental barrier or containment to encapsulate and treat hazardous materials against toxic flow in a subsurface engineering system.

Beschreibung: For the countries with a developed stone industry the waste generated in the natural stone processing plants pose environmental and economic problems. The utilisation of stone waste in various areas is still under research. In addition, there are only a limited number of studies concerning the use of stone waste obtained from processing plants in the stabilisation of clayey soil. Furthermore, none of the studies in the literature investigated the effect of the characteristics of the stone on the stabilisation of the soil. This is the first study that compares the efficiency of the waste calcitic marble, dolomitic marble and granite powder as additives for the stabilisation of clayey soil. Artificial soil samples were prepared in the laboratory using bentonite and kaolinite. Natural stone waste powder was added to the soil samples at different percentages, and the index and compaction parameters of the stabilised soil were analysed. The results showed that the types of waste powder used in this study, like lime, could be used as stabilisers. As the percentage of additives increased, the plasticity index of the clayey soil decreased and the physical properties of the soil changed from clay to silt. In terms of compaction parameters, the use of all types of natural waste powder in the study resulted in a decrease in the optimum water content and an increase in the maximum dry unit weight. The lowest optimum water content and the highest maximum dry unit weight were obtained from the dolomitic marble powder.

Beschreibung: Tuffs have been used as a construction material possibly since ancient times. In Afyonkarahisar, Turkey, there are numerous buildings constructed by tuff. Tuff has been a local construction material, during the Roman, Seljuk and Ottoman periods. Even though tuffs have relatively low durability and low strength values compared to marble, etc., they have survived with no major deterioration failures on many historical buildings. It has also been preferred because of its high porous texture, lightweight and easy shaping and process properties in the building sector. Naturally, it would be easily affected by water and humidity because of its porous structure. However, having this kind of structure leads to poor durability properties due to keeping water in it. The main objective of this study was to evaluate the physical and mechanical properties of the tuff quarried from the region and possible water effect, which may lead to degradation of its strength and durability of the material, thereby shortening the life span of the building structure used. Samples, which were tested after exposing to water and the freeze and thaw effects, were measured at a certain time. In this study, uniaxial compressive strength and flexural strength tests were conducted on test samples. The test results indicate that water may deteriorate the tuff’s strength properties and durability of the materials in due time.

Beschreibung: Based on data measured by eddy covariance (EC) and the Kormann and Meixner model, footprints of the flux of desert shrub ecosystems were analyzed. The contributions of different land types during the growing season in Fukang station in 2007 were estimated. Spatial distributions of footprint source areas were evaluated to reveal the relative flux contribution to the total flux over the entire observation period. The results indicate that: (1) The applied footprint model provides accurate footprint estimates and the flux data can be used for the shrub flux estimations. The flux contribution from shrub land showed that the observed flux data were able to represent seasonal change in the flux of desert shrub ecosystems. The flux contribution rate of shrub was highest during May to July between 10:00 and 18:00 h. (2) The location of the EC system in Fukang is appropriate for monitoring shrub flux. (3) Footprint analysis is necessary because it assesses the contribution of the target land-use type to the total flux for any user-defined period. The flux contribution rate was affected significantly by wind direction and the source region.

Beschreibung: Investigation of the extent of preferential flow and transport affected by several factors and their interactions in the vadose zone using the advanced measurement and modeling techniques is crucial for protection of groundwater from agricultural chemicals like fertilizers and pesticides. The objectives of this study were to investigate the interactive effects of factors like soil structure, initial soil water content (SWC), and application rate on preferential flow and transport using the time domain reflectometry (TDR) measurements of SWC and electrical conductivity (EC) in the plots of 12 treatments in a sandy clay field soil, applying the models (HYDRUS-1D and MACRO) to the measured data, performing Tukey test statistical analysis, and relating model parameters to basic soil properties, consequently, flow and transport characteristics. Analysis of response times and the changes in SWC and EC with time during the experiments in the profiles of the treatments confirmed the existence of preferential flow and transport at the site. As long as the other factors or conditions were constant; undisturbed versus disturbed soil, wet versus dry initial SWC, and high versus low application rate caused preferential flow and transport in the soil based on the TDR measurements. Overall HYDRUS-1D had better performance than MACRO in the simulations of the measured data. These results suggest that different scales of these factors in different field soils need to be further studied for better understanding the flow and transport processes in the vadose zone.

Beschreibung: The mercury (Hg) deposition history in the Darién Gulf is reconstructed from three sediment cores spanning up to 1,000 years. Knowledge on the contribution to global Hg budget from the Caribbean is limited. Patterns of water circulation, sediment deposition rates, cataclysmic atmospheric inputs, and post-depositional migration have been considered in Hg trapping in the seabed. The sediment delivery rates to the coastal zone over the Late Holocene have increased from 0.2 to 1 cm year −1 owing to anthropogenic influence. This alteration took the form of geological effects, like coastal morphology change, that played a major role in Hg downcore signal preservation. Natural background Hg levels in Southern Caribbean sediments (77.0 μg kg −1 ) are up to three times higher than preindustrial signals at other latitudes, because of volcanic contributions from the Pacific ring of fire. Enrichment factors rose from 0.9 to 1.5 (70.1–113.5 μg kg −1 ) within profiles related to Hg usage since Spanish colonial times between the calendar years 1550 and 1811.

Beschreibung: Sediment samples, collected from a large shallow lake, Taihu, China, were incubated in two conditions (with and without air extraction) with regard to four soil enzyme’s inhibitors (dry and moist heat sterilizations, chloramphenicol and toluene) to estimate the potential nitrate reductase (Nar) activities. The objectives of paper were to define (1) whether to exclude air from the mixture of sediment and substrate solution prior to incubation was necessary, and (2) the efficacy of four inhibitors when assaying the enzyme. No significant difference between two incubation methods was found ( P  〈 0.05), indicating that it is not necessary for estimating the potential Nar activity in the sediment to construct an initial anaerobic condition by air extractions prior to incubation. Toluene (1.0 mL/g sediment) and dry heat sterilization effectively and persistently inhibit the reduction of nitrate to nitrite during the incubation of 42 h. The authors concluded that both should be used as preferred inhibitors. In contrast, chloramphenicol (30 μg/g sediment) and moist heat sterilization inhibitors restrained nitrate reduction for 〈24 h only. In addition, it was found that no nitrite produced was substantially reduced in 24 h. Therefore, it should be needless for potential Nar activity estimation in the sediment to add 2,4-dinitrophenol to inhibit nitrite reductase.

Beschreibung: Rockbursts occurring on tunnel floors are a special form of failure encountered in tunnel projects, where the failure is characterized by uplift, fracturing, and severe shocks of the tunnel floor. Extremely intense rockbursts were encountered during the excavation of the headrace tunnels 2 and 4 at the Jinping II Hydropower Station. In this study, results of comprehensive analysis conducted using the combination of numerical methods, experiments, and onsite survey to analyze the occurrence and development process of the rockburst are presented. In addition, the degree and extension range of the surrounding rock mass damage were estimated using the failure approaching index and the local energy release rate. The results of the analysis presented in this study are expected to advance the existing knowledge of special rockburst forms and may also serve as a reference for the design of resistant measures for other similar rockbursts.

Beschreibung: In order to understand the groundwater dynamics and to improve the management of water resources in the Federal District of Brazil, this research proposes a 3D groundwater flow model to represent the groundwater level and flow system. The selected test site was the Pipiripau catchment. The development of the model was based on available geological, hydrogeological, geomorphological, climatological and pedological data. Geological and hydrogeological data were used to generate the 3D groundwater flow model. The 3D mesh elements of the domain were generated through the Groundwater Modeling System software, based on the logs of the well materials. The numerical simulation of the finite element method was implemented in the framework of the scientific software OpenGeoSys. With the 3D mesh-appropriated boundary conditions, annual average infiltration data and hydrogeological parameters were incorporated. Afterwards, the steady-state model was calibrated by the PEST software using available data of the water level from wells. The results showed the distribution of the steady-state hydraulic heads in the model domain, where the highest values occurred in the east and west recharge areas and the lowest values were found in the southwest of the basin. The results of this study can be a used as initial condition for the transient groundwater flow simulation and to provide a scientific basis for water resource management.

Beschreibung: This study attempts to assess the aquifer vulnerability in the northeastern sector of the Campania Plain (southern Italy). The area is a highly populated region with anthropic impacts caused by rapid urban growth, quarrying, agricultural and industrial activities and uncontrolled waste storage. The main geologic feature of this plain is the alternation of alluvial/transitional and volcaniclastic deposits of Late Pleistocene–Holocene age. The study was performed integrating different sets of geologic and environmental data to restore the stratigraphic architecture and to assess anthropic impacts on subsoil. The reconstruction of stratigraphic subsurface architecture was based on remarkable geodatabase, concerning well log stratigraphies. Specific insights have been delineated on the volcaniclastic lithofacies heteropies across the entire area of study to highlight the differences in lithification degree and permeability. The contribution of pedogenesis on the reconstruction of the stratigraphic setting was also considered for the relative implications on groundwater quality concerns, as paleosols are usually regarded as aquitards. All of this information has been managed into a GIS project to produce a detailed 3D geological reconstruction, integrated with hydrogeological information to provide a model of the aquifer under study, highlighting sites of greater vulnerability to pollution. The anthropic impacts on subsoil were assessed by evaluating land-uses and overlaying the ANHI (Agricultural Nitrate Hazard Index) Map. The integration of the above datasets has allowed to check the reliability of the previsional empirical model with respect to the hydrostratigraphic model based on a thorough stratigraphic model and to verify the real potential of contamination.

Beschreibung: In the Republic of Djibouti (Horn of Africa), fractured volcanic aquifers are the main water resources. The country undergoes an arid climate. Alluvial aquifers exist in the wadis (intermittent streams) valleys and, in relation with volcanic aquifers, form complex volcano-sedimentary systems. Due to increasing water demands, groundwater resources are overexploited and require a rigorous management. This paper is focused on the Dalha basalts aquifer, located in the Dikhil area (Southwest of Djibouti). This aquifer is of vital importance for this area. Hydrochemical data and isotopic tracers ( 18 O and 2 H) were used to identify factors and phenomena governing the groundwater’s mineralization. The Piper diagram shows complex water types. Results from multivariate statistical analyses highlight three water families according to their locations: (1) groundwater characterized by low ionic concentrations located at the wadis zones; (2) groundwater characterized by moderate salinity and (3) highly mineralized waters mainly flowing in the eastern and central part of the study area, in volcanic aquifers. Results from scatter plots, especially Na versus Cl and Br versus Cl, suggest that the origin of more saline waters is not from dissolution of halite. The δ 18 O and δ 2 H data indicate that the groundwater flowing in the alluvial aquifer is of meteoric origin and fast percolation of rainwater occurs in the volcanic aquifers. These findings provide a preliminary understanding of the overall functioning of this complex volcano-sedimentary system. Additional investigations (pumping tests, numerical modeling) are in progress to achieve a more comprehensive understanding of this system.

Beschreibung: Global curve-fitting method (GCFM) is regarded as an effective approach in hydrogeological parameter estimation, as it integrates and uses pumping data and water recovery data of a transient pumping test for parameter estimation. The impacts of pumping duration on hydrogeological parameter estimation by GCFM were investigated in the present study using 2 in situ pumping tests and 24 simulated transient pumping tests. Empirical formulas for determining the optimal pumping duration were derived. The study results suggest that pumping duration will have impacts on the accuracy of hydrogeological parameter estimation. When pumping duration is longer than a certain period, relative errors of hydrogeological parameter estimation keep relatively stable within an acceptable limit. Therefore, it is unnecessary to continue the pumping for a very long time after the groundwater level has become stable. When the change rate of drawdown over time ( γ ) in an observation well located within a distance of 100 m to the pumping well reaches 0.134, the pumping can be stopped. If there are more than one observation wells in a pumping test, the smallest γ value should be selected to determine the optimal pumping duration. This research is meaningful in the instruction of pumping tests, and will reduce test costs greatly.

Beschreibung: Macropores resulting from soil pedogenesis and biological activity play important roles in soil water and chemical transport. Numerous studies have examined individual macropores and the effects of their size on solute transport, but few have assessed the effects of macropore continuity and of neighboring macropores. This paper describes a laboratory investigation of the effects of macropores, with varying degrees and types of continuity, on the transport and distribution of solutes in a sandy soil from the northern Loess Plateau, China. Breakthrough curves were obtained from 60 cm tall, 2-D columns containing standardized artificial macropores using an input solution of 1,190 mg/L KBr and 100 mg/L FD&C Blue #1 under a constant hydraulic head of 8 cm. The types of macropore were: open at both the surface and bottom of the soil column (O–O); open at the surface, closed at the bottom (O–C); and closed at the surface, open at the bottom (C–O). Columns with no macropores served as a control. In the O–O columns the solution reached the bottom 10–50 times faster than in any other treatment, bypassing most of the soil matrix. The presence of an O–C macropore resulted in weak retardation and much deeper penetration of the bromide and FD&C Blue #1 solution than in the control columns. However, the C–O macropore had little effect on either breakthrough curves or solute distributions. In further experiments that considered neighboring macropores effects, an inclined macropore strongly affected solute concentrations in the profile around a nearby vertical macropore. It was concluded that the length, type and position of single macropores, and the presence of neighboring macropores, all affect soil water flow and solute infiltration parameters in a sandy loam soil.

Beschreibung: Shrubs that exert drag force on the wind significantly affect the air–surface interaction in arid and semiarid regions, and some coastal regions where aeolian processes are active. An understanding of the drag force on wind of shrubs provides important information on the dynamics of shrubs in reducing wind erosion, and their geomorphological significances. Thus, we analyzed the drag force and drag coefficient for model shrubs using wind measurements obtained by particle image velocimetry in a scaled wind tunnel simulation. The drag force was found to be a function of wind velocity and shrub density. Both drag force and drag coefficient revealed a critical shrub density of around 0.08. The vertical drag force changed direction when the shrub density became greater or less than the critical density. The drag coefficient increased rapidly with shrub density when the density was below 0.08, but it increased very gently when the density was increased beyond the critical value. The results have an important theoretical significance for our understanding of the dynamics of vegetated dunes and the windbreak mechanism of shrubs.

Beschreibung: A study was made to determine the influence of pasture degradation on soil quality indicators that included physical, chemical, biological and micromorphological attributes, along the hillslope positions in Chaharmahal and Bakhtiari province, western Iran. Soil samples from different slope positions were collected from 0 to 30 cm depth for physical and chemical properties and from 0 to 15 cm depth for biological properties at two adjacent sites in the two ecosystems: natural pasture and cultivated land. Soil quality indicators including bulk density, mean weight diameter, soil organic carbon (SOC), particulate organic material (POM) in aggregate fractions, total nitrogen, available potassium, available phosphorus, cation exchange capacity, soil microbial respiration (SMR) and microbial biomass C and N were determined. The results showed that SOC decreased cultivation from 1.09 to 0.77 % following pasture degradation. The POM decreased by about 19.35 % in cultivated soils when compared to natural pasture; also, SMR and microbial biomass C and N decreased significantly following pasture degradation. Furthermore, aggregate stability and pore spaces decreased, and bulk density increased in the cultivated soils. Overall, our results showed that long-term cultivation following pasture degradation led to a decline in soil quality in all selected slope positions at the site studied in the semiarid region.

Beschreibung: The state of Punjab—a part of the Indus basin of the Indian subcontinent has an excellent net work of irrigation facilities. However, due to intensive cultivation it is facing a major problem with respect to quality of groundwater for irrigation. In the present investigation, geo-referenced groundwater samples were analysed to map water quality using geographical information system. Electrical conductivity varied from 0.418 to 5.754 dS m −1 with an average of 1.365 dS m −1 . The carbonate ranged between 0 and 120 mg L −1 , whereas bicarbonate ranged from 5 to 1,000 mg L −1 . Chloride varied from 7 to 2,347 mg L −1 . Calcium plus magnesium ranged from 12 to 1,216 mg L −1 with a mean value of 169 mg L −1 . Sodium adsorption ratio ranged between 0.0 and 34.78 with an average of 2.66 meq L −1/2 . Residual sodium carbonate varied from 0 to 21.30 meq L −1 with a standard deviation of 2.24. The Geographic Information System (GIS)-based mapping indicated that water in suitable category spatially covered 45.7 % of the state which is located mostly in the sub-mountain (Siwalik Hills), north-eastern undulating and piedmont and alluvial plain agro-eco-subregions. Marginally suitable groundwater spatially covered 46.1 % in the central alluvial plain and south-western alluvial plain agro-eco-subregions. Unsuitable groundwater covered 8.2 % of the state, mostly in the erstwhile sodic soils areas in the central alluvial plain and south-western alluvial plain agro-eco-subregions. GIS-based maps are effective in identifying hot spots which need immediate attention and call for strategic planning for sustainable management.

Beschreibung: The stable isotope nitrogen-15 ( 15 N) is a robust indicator of nitrogen (N) source, and the joint use of δ 15 N and δ 18 O–NO 3 − values can provide more useful information about nitrate source discrimination and N cycle process. The δ 15 N and δ 18 O–NO 3 − values, as well as major ion tracers, from Taihu Lake in east China were investigated to identify the primary nitrate sources and assess nitrate biogeochemical process in the present study. The results show that the nitrate concentration in West Taihu Lake (WTL) was generally higher than those in East Taihu Lake (ETL) and its upstream inflow rivers. The NO 3 − /Cl − value combined with mapping of δ 15 N–NO 3 − and NO 3 − concentration suggest that the mixing process should play a major effect in WTL, and denitrification was the dominant N transformation process in WTL. A linear relationship of close to ~1: 2 was observed between δ 15 N–NO 3 − and δ 18 O–NO 3 − values in WTL, confirming the occurrence of denitrification in WTL. The δ 15 N–NO 3 − data imply that sewage and manure were the principal nitrate sources in WTL and its feeder rivers, while the nitrate in ETL might derive from soil organic nitrogen and atmospheric deposition. The δ 18 O–NO 3 − data indicate most of nitrate from microbial nitrification of organic nitrogen matter possibly make a significant contribution to the lake.

Beschreibung: Carbon sequestration in shallow aquifers can be facilitated by water withdrawal. The factors that optimize the injection/withdrawal balance to minimize potential environmental impacts have been studied, including reservoir size, well pattern, injection rate, reservoir heterogeneity, anisotropy ratio, and permeability sequence. The effects of these factors on CO 2 storage capacity and efficiency were studied using a compositional simulator Computer Modeling Group-General Equation of State Model, which modeled features including residual gas trapping, CO 2 solubility, and mineralization reactions. Two terms, storage efficiency and CO 2 relative breakthrough time, were introduced to better describe the problem. The simulation results show that simultaneous water withdrawal during CO 2 injection greatly improves CO 2 storage capacity and efficiency. A certain degree of heterogeneity or anisotropy benefits CO 2 storage. A high injection rate favors storage capacity, but reduces the storage efficiency and CO 2 breakthrough time, which in turn limits the total amount of CO 2 injected.

Beschreibung: Harmful algal blooms commonly known as red tides have been observed at increasing frequencies, which are causing serious economic and ecologic problems in Haizhou Bay off the eastern coast of China. It is important to study the inducing factors of red tides including a wide variety of environmental variables and the complex interactions between them. This study explores the possibility of predicting the occurrence of red tides using support vector machine (SVM) with environmental variables. Seventeen in situ environmental variables which are known to affect the occurrence of red tides were collected between May and October of 2004–2006. Seven characteristic factors were extracted from these variables via factorial analysis to reduce computation complexity. Three of them are related to nutrients, others are contributed by temperature, oxygen depletion, pH, hydrodynamics, and precipitation, respectively. The classification models based on SVM were constructed to identify the red tides samples using the seven factors as independent variables and radial basis function as the kernel function. The model with the combination parameters of C  = 10, γ  = 0.7, and ζ  = 0.1 has the highest accuracy of 92.06 %. It indicates that the model is highly valuable in predicting the occurrence of red tides by environmental variables in this region for its conservative threshold of surface algae concentration.

Beschreibung: Our News in Brief series is designed to offer different views revolving around the earth sciences, as various experts will be invited to provide a brief look around the recent research conducted in their area. The selection of research papers is left up to each expert and due to the broadness of each field is not intended to be a comprehensive overview. Links to the published work are provided in each section. In this issue we have invited Stephanie Hänsel, a postdoctoral senior researcher at the Interdisciplinary Environmental Research Center in Freiberg Germany, to select and summarize some of the latest findings in climate science. In this second article of our series, Hänsel gives a brief rundown on five research papers of global relevance.

Beschreibung: To understand the mechanism of arsenic mobilization from sediment to groundwater mediated by microorganism, vertical distribution of bacterial populations in aquifer sediments of the Hetao plain, Inner Mongolia was investigated by a two-step nested PCR-DGGE and 16S rRNA gene clone libraries, combined with sediment geochemistry. A borehole to 30 m depth was drilled and 11 sediment samples were collected. Lithological profile and different geochemical characteristics of sediments indicated a distinct transition of oxidizing–reducing environment along the depth of the sediment core. As(III) and Fe(II) concentrations elevated progressively from 10 m, simultaneously coupling with decrease of As(V) and Fe(III) concentrations, implying that reductive dissolution of arsenic-rich Fe(III) oxyhydroxides led to arsenic release. Results of DGGE displayed that sediment samples with higher concentrations of total arsenic and total organic carbon had lower population diversity, which suggested total arsenic concentrations were important to determine the population diversity of sediments. Bacterial communities of a sediment sample with the highest diversity and ratio of As(III) to total As were dominated by aerobic and facultative anaerobic bacteria and belonged to Alpha -, Beta -, and Gammaproteobacteria and Firmicutes group. Most of the retrieved sequences were closely related to high arsenic-resistance organisms, sulfide/thiosulfate oxidizers, denitrifiers, and aromatic hydrocarbon degraders. Thiobacillus distinctly predominated in clone library, which suggested that arsenic might be released by oxidized dissolution of sulfide minerals coupled to arsenate reduction or nitrate reduction in anaerobic condition. These data have important implications for understanding the microbially mediated arsenic mobilization in aquifers.

Beschreibung: Elevated polycyclic aromatic hydrocarbon (PAH) concentrations were determined in different Chinese coals, with the highest concentrations in bituminous coals. Phenanthrene (Phen) was chosen as the probe compound for PAHs to study the sorption behavior of coal. No native Phen was detected in desorption experiments indicating irreversible sorption–desorption behavior of PAHs in raw coal samples. Sorption mechanism was further studied under varying conditions of pH value and ionic strength. Different ranks of coal showed different sorption behavior under acidic, neutral, and alkaline conditions. Batch experiments were further processed for the selected coals at pH values from 3 to 11 at a constant aqueous concentration. Sorption capacities of all coals decreased with increased pH except for YJ coal. Furthermore, although DOC-associated Phen mass contributed little to the total Phen mass under different pH values, the significant negative correlations between M DOC and log K OC values were observed for all coal samples, indicating a significant role played by DOC in the coal sorption. In addition, sorption experiments under varying ionic strength showed that the ionic strength influence was more obvious in sorption isotherms for higher rank coals with increasing ionic strength, and this effect was most significant when ionic strength increased from 0 to 0.15 M, especially at relatively low aqueous concentrations.

Beschreibung: Hydraulic fracturing is increasingly being used to produce gas from unconventional resource sites for energy supply. Therefore, concerns about risks of this technology related to human health and the environment have to be addressed. Among the major issues is the potential contamination of surrounding water systems by chemical additives used in fracturing fluids. In this study, the ecotoxicological hazards of fracturing fluids, both, their individual components (chemicals) as well as their mixtures (product) were assessed using a component-based mixture approach. For five exemplary fracturing fluids, 40–90 wt% of the contained substances could unambiguously be defined in their chemical identity. The concentrations used in the applied fluid mixture were considered as (maximum) exposure concentrations. For components with mass fractions between 10 and 74 wt%, the effect concentrations for acute and chronic toxicity of fish, daphnia and algae were retrieved from experimental databases and through predictive modeling. The hazard indices calculated from the ratio of exposure to effect concentration were 〉1 for all fracturing fluids, using different scenarios. This indicated a hazard from the undiluted fracturing fluids. The assessment framework presented in this study allows for dealing with data gaps and uncertainties in a tiered fashion and in particular accommodates for combined effects resulting from chemical mixtures. It might be employed for ecotoxicological risk assessment of products containing chemical mixtures and optimization of their environmental performance.

Beschreibung: The systematic sampling of the chemical composition of the groundwater from five karst springs (including an overflow spring) and one outflowing borehole have permitted to determine distinctive chemical changes in the waters that reflect the geochemical processes occurring in a carbonate aquifer system from southern Spain. The analysis of the dissolution parameters revealed that geochemical evolution of the karst waters basically depends on the availability of the minerals forming aquifer rocks and the residence time within the aquifers. In the three proposed scenarios in the aquifers, which include the preferential flow routines, the more important geochemical processes taking place during the groundwater flow from the recharge to the discharge zones are: CO 2 dissolution and exsolution (outgassing), calcite net dissolution, calcite and dolomite sequential dissolution, gypsum/anhydrite and halite dissolution, de-dolomitization and calcite precipitation. A detailed analysis of the hydrochemical data set, saturation indices of the minerals and partial pressure of CO 2 in the waters joined to the application of geochemical modelling methods allowed the elaboration of a hydrogeochemical model of the studied aquifers. The developed approach contributes to a better understanding of the karstification processes and the hydrogeological functioning of carbonate aquifers, the latter being a crucial aspect for the suitable management of the water resources.

Beschreibung: Groundwater is the most important natural resource used for drinking by many people around the world, especially in arid and semi-arid areas. The resource cannot be optimally used and sustained unless the quality of groundwater is assessed. Saveh-Nobaran aquifer in Iran is the most important groundwater aquiferous system in the region which is considered a major source for drinking and irrigation. The main objective of this study is to understand the groundwater quality status of Saveh-Nobaran aquifer, followed by attempts to investigate the spatial distribution of groundwater quality parameters to identify places with the best quality for drinking consume within the study area. For this purpose, a set of original data, as yet unpublished, is presented. This paper provides an important contribution for understanding relationship between land use and groundwater quality, and also groundwater depth and groundwater quality. This goal has been achieved with the combined use of the Water Quality Index (WQI) and a geographical information system (GIS). A total of 58 groundwater samples were collected and analyzed for major cations and anions. Spatial distribution maps of pH, TDS, EC, TH, Cl, HCO, SO 4 , Ca, Mg, Na and K have been created using the kriging method in a GIS environment. From the WQI assessment, over 65 % of the water samples fall within the ‘‘Poor’’, ‘‘Very poor’’ and “unsuitable for drinking” categories, suggesting that groundwater from the center and north-east of the Saveh-Nobaran aquifer is unsuitable for drinking purposes. This research and its results have shown the great combination use of GIS and WQI in assessing groundwater quality. Having a clear view of the geographic areas of groundwater quality, decision makers can plan better for the operation and maintenance of groundwater resources.

Beschreibung: The role of CO 2 in karst has been of interest for decades, and emphasized by IGCP 379, International Geoscience Programme, UNESCO started in 1995. There are still open questions about the dynamics of carbon in karst systems, particularly the flux of carbon between the surface and subsurface and between different components in the karst subsurface. This research report focuses on the variations of hydrochemistry and P CO 2 (partial pressures of carbon dioxide) in subtropical karst groundwater, using high-resolution auto-monitoring hydrochemical data (15-min intervals). The aim of this study was to understand how hydrochemistry and P CO 2 in karst systems respond to recharge over different time scales and what the controlling factors are. An auto-monitoring hydrochemistry station was installed about 300 m upstream from the exit in the active stream channel of Xueyu Cave, a typical subtropical karst cave. Four years of high-resolution continuous pH, specific conductivity (Spc), temperature and water-level data were collected. A thermodynamic model was used to link the continuous data to monthly water quality data, allowing the calculation of CO 2 partial pressures and calcite saturation (SIc) levels on a continuous basis. Seasonal, diurnal and storm-scale variations were captured in the hydrochemistry and calculated P CO 2 records, indicating that the cave stream is a dynamic and variable system. Seasonal features (higher specific conductivity and lower pH in summer; lower specific conductivity and higher pH in winter) tend to covary with temperature which influences the production of CO 2 in soils, thus being the driving force for the variations (the soil CO 2 effect). Due to the buffer effect of a thick vadose zone and large void cave space, diurnal variations are not obvious compared with epikarst springs in SW China. Storm-scale fluctuations due to storm events occur during the summer rainy season. Piston flow effects, dilution and soil CO 2 effects determine the variations in different storm events. At the beginning of the rains, the piston effect drives the variations, characterized by increase in Spc, SIc and pH in the cave stream and decrease in P CO 2 . With heavy rainfall, decrease in Spc shows control by the dilution effect, while decrease in SIc and pH and increase in P CO 2 indicates the greater influence of soil CO 2 . These results imply that the soil and cave voids are important factors influencing the hydrochemical evolution of karst groundwater. Future works need to use such high-resolution technology widely for tracing the P CO 2 and hydrochemical variations in different karst aquifers.

Beschreibung: Changes in the concentrations of atmospheric greenhouse gases are an important part of the global climate forcing. The hypothesis that benthic foraminifera are useful proxies of local methane emission from the seafloor has been verified on sediment cores by numerous studies. The calcium carbonate (CaCO 3 ) content and the high-resolution carbon and oxygen isotope composition of the benthic foraminifera from the core 08CF7, from the northeastern Shenhu gas hydrate drilling area in the Baiyun Sag of the northern South China Sea were analyzed, and the benthic foraminifera’s evidence for methane release from gas hydrate decomposition are presented here for the first time. Two rapid obvious carbon isotope negative excursions were observed in the oxygen isotope stage boundaries 5d/5c and 6/5e (penultimate deglaciation, about 130 ka) of the cold-to-warm climatic transition period. The largest negative value of δ 13 C is about −2.95 ‰, and the whole change of carbon and oxygen isotope is strikingly similar and is in consonance with the atmospheric methane concentration recorded by the Vostok ice core and the carbon isotopic record from Lake Baikal. Combining these results with the analysis of the geological conditions of the study area and the fact that gas hydrate exists in the surrounding area, it can be concluded that the carbon isotope negative excursions of the benthic foraminifera in the northern South China Sea are associated with methane release from gas hydrate decomposition due to deglacial climate warming. By recording the episodes of massive gas hydrate decomposition closely linked with the northern hemisphere temperatures during major warming periods, the new δ 13 C record from the Baiyun Sag provides further evidence for the potential impact of gas hydrate reservoir on rapid deglacial rises of atmospheric methane levels.

Beschreibung: The Ahvaz oil field located in southern Iran has been identified as a possible point of elemental pollution, since elevated levels of metallic pollution (As, Cd, Cr, Ni, Cu, Zn, Pb and V) have been introduced to the adjacent environment through the oil excavation activities. The concentration of metals Cr, Ni, Cu, Pb and Zn are far below all reference values while that of As, Cd and V are remarkably above limits. Enrichment factor (EF) reports the mean waste status to be enriched by all three elements As, Cd and V while the Igeo values manifest the strongly polluted condition for Cd and moderately polluted for As and V. In order to quantify the association of metal concentrations with various Acid soluble, reducible, oxidizable and pseudo-total phases and consequently to estimate the potential mobility of existent metallic pollution, the sequential chemical partitioning technique was used for the samples collected from clean soil, drilling mud and wastage pit. According to the results achieved by chemical partitioning analysis, Cd seems to be mobile. Similar conditions exist for V with relatively lower risk level. Regarding As, the potential mobility is estimated to be low as a remarkable portion of bulk concentration (more than 70 %) is accumulated in the pseudo-total phase. Paying attention to the bulk and partitioning concentrations of three enriched elements in the drilling mud, it is concluded that the main cause of wastage pit contamination may be attributed to the nature of drilling mud utilized in excavation activities. Additionally, the geological texture in different depths may also play a role in this scenario.

Beschreibung: The distribution, accumulation, and ecological risk of heavy metals (Cu, Cd, Pb, Zn, Ni, Cr, and As) in the surface sediment were investigated in the upper reaches of Hunhe River, Northeast China. Sediment samples from 51 points throughout the upper reaches of Hunhe River were collected and measured for heavy metal concentrations, TN content, and TP content. Results showed that heavy metal concentrations at the vicinity of mines and towns were higher than those at other locations. According to sediment quality guidelines (SQGs), Cd and Zn were enriched in the sediments. The correlation analysis and principal component analysis (PCA) were conducted to assess the heavy metal sources. Close correlations between metal distribution and TP indicated that the sediments may be affected by application of phosphate fertilizer. Elements, Cu, Cd, Pb, Zn, and As, were grouped together, reflecting they were released from the same sources. PCA suggested that their primary sources were anthropogenic, namely mining and extensive use of fertilizers. Therefore, heavy metal pollution due to mining and agricultural intensification in the upper Hunhe River basin should be taken into account during the formation of regional management strategies for the water environment.

Beschreibung: The Shengli River–Changshe Mountain oil shale zone represents a potentially large marine oil shale resource in China. With the aim of better understanding the geochemistry of trace elements in marine oil shale and its combustion residues, 40 raw samples, 27 oil shale combustion residues and 29 selected minerals from Changliang Mountain oil shale are studied for geochemical analyses. The contents of Se, Cd, Mo, As, Cs, Pb, Sr and U in the oil shale samples are enriched from 1.47 to 33.91 times as compared with the Clarke values, whereas the concentrations of other elements are slightly higher/lower than the respective worldwide means. The most enriched elements in oil shale combustion residues are Se, Cd, Mo, As and U with enrichment values from 4.78 to 50.92. Trace elements with high volatile behaviour such as As, Co, Ni, Sc, Sn and V occur predominantly in organic matter and/or sulphides. Other non-volatile or slightly volatile trace elements (e.g., Be, Bi, Cs, Cu, Ga, Hf, Li, Nb, Rb, Ta, Th, W, Zr and REEs) may occur mainly in original and relatively refractory minerals in raw oil shale. The potentially hazardous trace elements in Changliang Mountain oil shale include As, Cd, Mo and Se. Arsenic and Se are controlled mainly by Fe-bearing minerals (probably pyrite) in Changliang Mountain oil shale. Cadmium is present mainly in dolomite, while Mo occurs mainly in organic matter.

Beschreibung: The characteristics of wetland research were investigated by a bibliometric analysis of the top-cited wetland-related articles since 1899 based on the Science Citation Index Expanded database. The analyzed aspects included the distribution of journals, and publications by country, institution, and author, with five indicators including total articles, and independent, collaborative, first-author, and corresponding-author articles. Results showed that 188 articles on wetlands have been cited at least 100 times since their publication year to 2011. The most productive stage was 1991–2000, accounting for approximately seven-tenths of the top-cited articles. The US was the leading country, followed distantly by 25 other countries/territories. The US also held primacy in terms of productive institutions. The US Geological Survey ranked first according to the five indicators. The 188 top-cited articles had 637 authors, among whom W.J. Mitsch published the most first-author and corresponding-author articles. Furthermore, substance circulation (especially of carbon), wetland organisms and vegetation, and modeling methodology were the main focuses of wetland research in the past few years. In 2011, wetland organisms and vegetation were the hottest research topics. These results were coincident with a previous study on total publications, and revealed more-specific characteristics and hotspots of wetland research.

Beschreibung: The study demonstrates the potential of geographical information system and statistical-based approaches to identify the hydrological processes and demarcate the groundwater prospect zones of the Gangolli basin, Karnataka State, India. The basin is situated in humid tropical climate and influenced by three major rivers viz. Kollur (6th order stream), Chakra (6th order stream) and Haladi (7th order stream) which cover an area of ~1,512 km 2 and cumulative length of ~84 km. Various thematic maps—drainage, geomorphology, geology, slope, soil, lineament and lineament density—were prepared using Survey of India topographic maps, Indian remote sensing (IRS-P6) images and other published maps. Hydrogeomorphologic characteristics were correlated with different morphometric parameters to identify the hydrological processes and demarcate the groundwater potential zones of the basin. All the hydrological units and morphometric parameters were assigned suitable weightages according to their relative importance to groundwater potentiality to identify the most deficit/surplus zones of groundwater. Based on hydrological characteristics, integrated thematic maps reveal that ~14 % (~217 km 2 ) of basin area falls under very good, ~32 % (~486 km 2 ) under good, ~23 % (~353 km 2 ) under moderate, and 30 % (~443 km 2 ) under poor zones for groundwater potential. From the sub-basin-wise prioritisation, it has been inferred that SB-III scored highest groundwater potential, followed by SB-X. Result of morphometric analyses with the hydrologic parameters indicates that ~99 % area of SB-III and SB-X are under very good to moderate groundwater potential zone. This study clearly demonstrates that hydrological parameters in relation with morphometric analyses are useful to demarcate the prospect zones of groundwater.

Beschreibung: The leachate levels in the landfills in southern China are generally high. Field monitoring was carried out in the Suzhou landfill to investigate the leachate mound. The saturated hydraulic conductivity and soil–water characteristic curve (SWCC) of municipal solid waste were measured using samples taken from different depths of the landfill. Field monitoring reveals that a perched leachate mound and a substantial main leachate mound existed in the landfill. The saturated hydraulic conductivities of wastes in shallow, middle and deep depth were measured to be 4.81 × 10 −2 , 3.50 × 10 −3 and 3.56 × 10 −4  cm/s, respectively. The results of SWCC tests show that the SWCC curve was steep when matric suction was low, and the shallower the waste the steeper would be the curve. In addition to the field and laboratory tests, an unsaturated–saturated seepage analysis was conducted to simulate the development of the high leachate mound and to calculate the annual leachate production. The simulated volumetric water content in the unsaturated zone was about 40 %, which agreed well with the test result. The calculated leachate mound was consistent with the field measurement. The calculated annual and daily leachate productions were all more reasonable than the results of the HELP model.

Beschreibung: The spatial distributions of Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn concentrations in surface soils of Guangdong Province, China, were investigated to evaluate the environmental quality of these potentially toxic elements using 261 samples. The following average concentrations were obtained: Cu, 17.4 mg/kg; Ni, 17.7 mg/kg; Cr, 56.7 mg/kg; Co, 6.8 mg/kg; Mn, 223.2 mg/kg; Pb, 36.6 mg/kg; Hg, 0.10 mg/kg; Cd, 0.09 mg/kg; Zn, 49.8 mg/kg. Correlation analysis was applied to the data matrix to evaluate the results and identify the possible sources of metals. Distribution maps of the elements were created using the inverse distance weighted interpolation method. The nine metals exhibited generally distinct geographical patterns. Results showed that 5,173 km 2 of the study area presented higher pollution indices and was slightly polluted.

Beschreibung: A multi-channel, steady-state flow-through (SSFT), soil-CO 2 flux monitoring system was modified to include a larger-diameter vent tube and an array of inexpensive pyroelectric non-dispersive infrared detectors for full-range (0–100 %) coverage of CO 2 concentrations without dilution. Field testing of this system was then conducted from late July to mid-September 2010 at the Zero Emissions Research and Technology project site located in Bozeman, Montana, USA. Subsequently, laboratory testing was conducted at the Pacific Northwest National Laboratory in Richland, WA, USA using a flux bucket filled with dry sand. In the field, an array of 25 SSFT and 3 non-steady-state (NSS) flux chambers was installed in a 10 × 4 m area, the long boundary of which was directly above a shallow (2-m depth) horizontal injection well located 0.5 m below the water table. Two additional chambers (one SSFT and one NSS) were installed 10 m from the well for background measurements. Volumetric soil moisture sensors were installed at each SSFT chamber to measure mean moisture levels in the top 0.15 m of soil. A total flux of 52 kg CO 2 day −1 was injected into the well for 27 days and the efflux from the soil was monitored by the chambers before, during, and for 27 days after the injection. Overall, the results were consistent with those from previous years, showing a radial efflux pattern centered on a known “hot spot”, rapid responses to changes in injection rate and wind power, evidence for movement of the CO 2 plume during the injection, and nominal flux levels from the SSFT chambers that were up to sevenfold higher than those measured by adjacent NSS chambers. Soil moisture levels varied during the experiment from moderate to near saturation with the highest levels occurring consistently at the hot spot. The effects of wind on measured flux were complex and decreased as soil moisture content increased. In the laboratory, flux-bucket testing with the SSFT chamber showed large measured-flux enhancement due to the Venturi effect on the chamber vent, but an overall decrease in measured flux when wind also reached the sand surface. Flux-bucket tests at a high flux (comparable to that at the hot spot) also showed that the measured flux levels increase linearly with the chamber-flushing rate until the actual level is reached. At the SSFT chamber-flushing rate used in the field experiment, the measured flux in the laboratory was only about a third of the actual flux. The ratio of measured to actual flux increased logarithmically as flux decreased, and reached parity at low levels typical of diffusive-flux systems. Taken together, the results suggest that values for advective CO 2 flux measured by SSFT and NSS chamber systems are likely to be significantly lower than the actual values due to back pressure developed in the chamber that diverts flux from entering the chamber. Chamber designs that counteract the back pressure and also avoid large Venturi effects associated with vent tubes, such as the SSFT with a narrow vent tube operated at a high chamber-flushing rate, are likely to yield flux measurements closer to the true values.

Beschreibung: Preliminary results of ambient indoor/outdoor gamma dose rates measured for Muzaffarabad city, the state capital of Azad Kashmir, are presented. Measurements of indoor/outdoor environmental exposures were carried out using a portable Ludlum Model 19 Micrometer. Effect of altitude on measured values of gamma dose rates has also been investigated. Besides measuring the gamma dose rates for indoor and open environment, measurements have also been taken within two coal mines. Effects of lithology on gamma dose rates have also been investigated. For outdoor measurements, minimum and maximum gamma dose rates were found as 533 ± 4.33 and 1,143 ± 2.96 μGy y −1 , while for indoor environment minimum and maximum gamma dose rate value were found as 533 ± 4.33 and 979 ± 3.2 μGy y −1 . Average values of indoor and outdoor gamma dose rates were found as 761 ± 3.62 and 710 ± 3.75 μGy y −1 . Gamma dose rates have also been calculated with altitude variations. Measured values of gamma dose rates show a weak positive correlation with altitude. For measurements made in coal mines, maximum gamma doses rate value was found as 3,490 ± 1.69 μGy y −1 , situated at a height of 1,098 m, located at Sangri Mera. Results obtained from the current study show that annual effective doses from gamma radiation exposure does not pose health threat to the population of district Muzaffarabad.

Beschreibung: Increased nitrogen (N) input to ecosystems could alter soil organic carbon (C) dynamics, but the effect still remains uncertain. To better understand the effect of N addition on soil organic C in wetland ecosystems, a field experiment was conducted in a seasonally inundated freshwater marsh, the Sanjiang Plain, Northeast China. In this study, litter production, soil total organic C (TOC) concentration, microbial biomass C (MBC), organic C mineralization, metabolic quotient ( q CO 2 ) and mineralization quotient ( q mC) in 0–15 cm depth were investigated after four consecutive years of N addition at four rates (CK, 0 g N m −2  year −1 ; low, 6 g N m −2  year −1 ; moderate, 12 g N m −2  year −1 ; high, 24 g N m −2  year −1 ). Four-year N addition increased litter production, and decreased soil organic C mineralization. In addition, soil TOC concentration and MBC generally increased at low and moderate N addition levels, but declined at high N addition level, whereas soil q CO 2 and q mC showed a reverse trend. These results suggest that short-term N addition alters soil organic C dynamics in seasonally inundated freshwater marshes of Northeast China, and the effects vary with N fertilization rates.

Beschreibung: The paper provides a coherent pattern identification analysis of the impacts of coastal land use and land cover (LULC) on evapotranspiration (ET) under the impact of seawater intrusion. The study applied the Landsat satellite data to characterize the LULC at Laizhou Bay, Shandong Province, China. Then, the ET and heat fluxes were estimated using the surface energy balance algorithm for land model with two-time phase thermal infrared band images and regional surface parameters. This allowed for the eventual linkage of seawater intrusion to land use/cover changes (LUCC) and ET variations over time. The case study discussed in this paper carried out a coastal landscape dynamics assessment using multi-source and multi-sensor remote sensing technologies. The results are: (1) due to its distance from the sea, the vegetation index (modified soil-adjusted vegetation index, MSAVI) gradually increases with the gradual increase of land use grade (Uindex); (2) there are a variety of types of relational patterns between parameters (LST, G n , MSAVI, and Uindex) and ET (positive, negative, and no relationship); and (3) seawater intrusion significantly affected the spatial pattern of LUCC, which evidently affected the spatial distribution of ET. The spatial distribution pattern and change characteristics of ET were formed by double driving forces of seawater intrusion and LUCC under the background effects of regional climate.

Beschreibung: Red mud (RM) was produced during alumina production from bauxite known as the Bayer process. Arsenic was detected in the solid phase of RM (RMsf) which was disposed in the disposal area. This study investigates the effectiveness of using Zero-valent iron (ZVI), ferrihydrite, ferrous sulfate (FeSO 4 ), waste acid (WA) or CO 2 for immobilization of arsenic in the RMsf. To test the effect of the amendments on the arsenic leachability, the RMsf samples were amended with the iron-based materials or acidifiers at various w/w (weight/weight) ratios (1–10 %) for 30 days. The leachability of arsenic in the RMsf was evaluated by a 4-step water elusion process. After 30-day treatment of the RMsf, the leachability of As decreased from an initial (12.7 %) to (7.0 %) with a w/w ratio of 5 % ZVI (0 %) with 5 % FeSO 4 ·7H 2 O, (3.4 %) with 5 % ferryhydrite, (2.0 %) with 6 % WA and (11.8 %) with 6 % CO 2 . FeSO 4 ·7H 2 O and WA showed more effectively than other amendments for immobilizing arsenic. Arsenic fractionation with a sequential extraction procedure was used to evaluate the arsenic migration potential in the RMsf. FeSO 4 and WA were effective in increasing the hydrous oxide combined arsenic in the RMsf. The leachable Cl − and SO 4 2− in the RMsf increased from 2.9 to 14.1 mg/g and 19.9–44.4 mg/g with 6 % WA and 5 % FeSO 4 ·7H 2 O added, respectively. The estimated cost of the FeSO 4 and WA treatment was 0.47 and 0.49 USD per ton, respectively.

Beschreibung: The feasibility of the industrial application of kapok fiber for the removal of lead (II) ions from aqueous stream was evaluated in this study. The fiber was modified using NaOH solution and also was oxidized with NaClO 2 solution. Both of the chemically enhanced kapok fibers showed a high adsorption efficiency, which was 23.4 and 34.6 mg/g, respectively, while unmodified kapok fibers had 4.70 mg/g. Kinetic reactions and their rate constants exhibited that the removal of lead was linearly correlated with adsorption capacity of the modified and oxidized kapok fibers. Adsorption isotherm of the experiment fitted very well with the Langmuir model for the chemically enhanced kapok fibers. Adsorption capacity decreased with a decrease in the pH. The recycling process of the used kapok fibers was also carried out and the results found that kapok fibers were reusable with relatively high regeneration rate.

Beschreibung: This study was conducted to identify the influence of three principal parameters constituting topography (slope inclination, soil depth, and slope length) on hillslope instability in a small catchment, known as Higashifukubegawa of Shikoku Island, western Japan. The typhoon rainfall of 19–20 October 2004 was significant in causing a total of seven slope failures in the catchment, though other rainfall events of various intensities in the same year did not cause failure. To understand the influence of the three principal parameters, numerical modeling of seepage and slope stability was performed in slope profiles constructed by varying the three parameters across their permissible range prepared from the seven slope failures of Higashifukubegawa in GeoStudio (GeoStudio Tutorials includes student edition lessons, Geo-Slope International Ltd., Calgary, 2005 v.4). The change in porewater pressure and slope mass weight due to variation in values of principal parameters was used to interpret the change in factor of safety or instability. The results showed that (1) instability increases with increase in the values of all three selected parameters across their range in Higashifukubegawa with remarkable decreasing trend in factors of safety, (2) slope inclination and soil depth were observed to affect instability through change in both unsaturated zone moisture content and mobilizing force of slope mass, (3) but with slope length, the unsaturated zone moisture content was not found to change considerably which implies that the instability due to slope length is mainly governed by change in slope mass weight. Overall, this study has dealt in great detail with how hillslope instability changes with principal parameters of topography under the same simulating conditions of hydrological and geo-mechanical parameters.

Beschreibung: The paper presents results of geothermal projects carried out in the last 23 years by the interdisciplinary research team at the AGH University of Science and Technology, in cooperation with numerous scientific institutions, published in the form of geothermal atlases in different parts of Poland. For many years, the Department of Fossil Fuels at the Faculty of Geology, Geophysics and Environmental Protection, AGH University of Science and Technology, has conducted the fundamental research and implementation work, aiming at the selection of optimum areas for utilization of geothermal waters and energy. Over the years, a methodology of estimation of geothermal resources with use of advanced techniques and numerical modeling has been developed. Recapitulation of the studies of the occurrence and utilization of geothermal waters and energy within geological units of the Polish Lowlands, Carpathians and Carpathian Foredeep has been reflected in seven Atlases. The Atlases represent a result of interdisciplinary, constructive cooperation of specialists from various, often remote fields of knowledge, fundamental and technological in nature, including: geologists, geophysicists, hydrogeologists, geochemists, drilling engineers, heat engineers, and many other specialists. The Atlases enable the selection of the most promising areas for utilization of geothermal waters and energy in Poland. The best geothermal conditions are predicted in the Polish Lowlands and Podhale region although in many areas of the Carpathians and the Carpathian Foredeep favorable geothermal conditions also occur.

Beschreibung: In the present work, remediation of lead-containing solution using raw and modified kaolinite has been presented. The micro and nanostructure of samples has been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Laser diffraction and scattering (LDS), was analyzed by particle size analyzer based on laser diffraction and particle size distribution (PSD) was done. The degree of metal adsorption was evaluated analyzing the Pb(II) contaminated samples by inductively coupled plasma atomic emission spectrometry (micro- and nanostructure on immobilization efficiency correlCP AES). The results show the impact of immobilization efficiency and ation between micro- and nanostructure. The thermodynamic data (Δ H °, Δ S °, Δ G °) are calculated from the temperature-dependent sorption isotherms. The results suggest sorption process of Pb(II) on kaolinite as spontaneous and endothermic.

Beschreibung: This study compares various immunomagnetic separation (IMS) protocols. The average recovery efficiency of IMS for different Salmonella concentrations (between 10 2 and 10 5 CFU/ml) was 53.5 ± 12.9 % ( n  = 24). When turbidity was less than 1,000 NTU, altering the debris ratio of water samples produced no significant changes in the recovery efficiency of IMS. Prolonging the incubation time or increasing the amount of immunomagnetic beads increased the recovery efficiency of IMS. This study also compares processes in which water samples were filtered, eluted/concentrated, and then processed by the IMS and non-IMS methods before PCR. Results indicate that IMS can effectively eliminate these inhibitors prior to polymerase chain reaction (PCR). The detection limit of Salmonella analysis process with IMS separation before enrichment was superior to IMS separation after enrichment. The proposed Salmonella analysis process, which included IMS to concentrate and purify the Salmonella , improves the sensitivity and the detection efficiency of the entire analysis process.

Beschreibung: The study of the stability of rock slope is very important because its instability can cause large disasters. Because the main influence factor of the stability of rock slope is the geological environment, the engineering experience analogy method is a practical and extensively applied method. The main feature of the engineering analogy method is the cluster. Based on the analysis of a dataset of rock slope samples and using the engineering analogy method in relation to the abstraction ant colony clustering algorithm, a new method for rock slope stability analysis is proposed. Using this method, rock slopes can be automatically clustered to obtain the stability status of rock slopes in one class. Therefore, the class rating can represent the stability status of rock slopes. Some real engineering examples are used to verify the computing effect of the new algorithm. Engineering applications prove that this new algorithm can automatically estimate the stability of rock slope with high validity. Its robustness surpasses the robustness of traditional algorithms, and its application is more convenient than that of traditional algorithms. However, as a heuristic algorithm, the selection of algorithm parameters is sometimes challenging, and the computation effect for a highly complex problem is not satisfactory. Therefore, this practical method of slope stability analysis should be popularized.

Beschreibung: Earthquakes can directly trigger multiple simultaneous slope failures in mountainous regions. Among these slope failures, flow-like landslides with high velocities and long run-outs can result in damage that is more destructive than other types of landslides. Timely and accurate recognition of the locations and magnitudes of flow-like landslides is essential for post-disaster relief. Synthetic aperture radar (SAR) sensors are suitable for deformation monitoring because of their capability to operate at day or night and in all weather conditions. Interferometric synthetic aperture radar (InSAR) is an advanced technique that extracts three-dimensional terrain and changes information from the radar images at a regional scale. The focus of this study is the Donghekou landslide-debris flow that was triggered by the 2008 Wenchuan earthquake. ALOS/PALSAR remote satellite images were interpreted by InSAR to generate digital surface elevation models. A comparison of data from a typical InSAR configuration with field survey data proves that the former is an effective method for rapidly detecting flow-like landslides in a mountainous area. The comparison also shows that the accuracy of the results is closely related to the correlation between the satellite radar images used, and further that the study accuracy would improve with the inclusion of better correlation. In this way, representations of pre- and post-landslide terrains could be generated for use in numerical simulations. The InSAR method has particular significance for areas without terrain data prior to slope failure, and can provide basic data for landslide hazard assessments.

Beschreibung: Erratum to: Spatial–temporal characteristics of surface water quality in the Taihu Basin, China Content Type Journal Article Pages 1-1 DOI 10.1007/s12665-011-1141-6 Authors Guangju Zhao, Institute of Soil and Water Conservation, Northwest A & F University, Yangling, 712100 People’s Republic of China Junfeng Gao, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008 People’s Republic of China Peng Tian, College of Water Resources and Architectural Engineering, Northwest A & F University, Yangling, 712100 People’s Republic of China Kun Tian, State Key Laboratory of Hydro-Science and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing, 100084 People’s Republic of China Guangheng Ni, State Key Laboratory of Hydro-Science and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing, 100084 People’s Republic of China Journal Environmental Earth Sciences Online ISSN 1866-6299 Print ISSN 1866-6280

Beschreibung:    A three-dimensional model for non-reactive solute transport in physically homogeneous subsurface porous media is presented. The model involves solution of the advection-dispersion equation, which additionally considered temporally dependent dispersion. The model also account for a uniform flow field, first-order decay which is inversely proportional to the dispersion coefficient and retardation factor. Porous media with semi-infinite domain is considered. Initially, the space domain is not solute free. Analytical solutions are obtained for uniform and varying pulse-type input source conditions. The governing solute transport equation is solved analytically by employing Laplace transformation technique (LTT). The solutions are illustrated and the behavior of solute transport may be observed for different values of retardation factor, for which simpler models that account for solute adsorption through a retardation factor may yield a misleading assessment of solute transport in ‘‘hydrologically sensitive’’ subsurface environments. Content Type Journal Article Pages 1-11 DOI 10.1007/s12665-011-1129-2 Authors R. R. Yadav, Department of Mathematics and Astronomy, Lucknow University, Lucknow, 226007 India Dilip Kumar Jaiswal, Department of Mathematics and Astronomy, Lucknow University, Lucknow, 226007 India Hareesh Kumar Yadav, Department of Mathematics and Astronomy, Lucknow University, Lucknow, 226007 India Gulrana, Department of Mathematics and Astronomy, Lucknow University, Lucknow, 226007 India Journal Environmental Earth Sciences Online ISSN 1866-6299 Print ISSN 1866-6280

Beschreibung:    To offer an insight into the toxicity of nanomaterials (NM) on the growth of bacteria, Escherichia coli ( E . coli ), Bacillus subtilis ( B . subtilis ) and Agrobacterium tumefaciens ( A . tumefaciens ) were exposed to nano-Au, nano-Ag, nano-Fe and fullerene (C 60 ) in this study. As an effective bactericide, nano-Ag induced high toxicity on these three bacteria; C 60 could inhibit their growth; however, B . subtilis and E . coli could recover as exposure time extended. Nano-Au and nano-Fe had hardly any effect on three bacteria. A . tumefaciens showed the lowest resistance and slowest growth rate during exposure. Images obtained by scanning electron microscope (SEM) revealed that nano-Ag could cause damage to the cell structure of three bacteria at 1 μg/mL. Slight damage on E. coli was found when exposed to C 60 , whereas no obvious physical damage was found after exposure to nano-Au or nano-Fe. It is assumed that surface activities of NM might be responsible for the different toxic effects on these bacteria. Content Type Journal Article Pages 1-7 DOI 10.1007/s12665-011-1139-0 Authors Chang Wang, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085 People’s Republic of China Ling Wang, Key Lab of Subtropical Agriculture and Environment, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, 430070 People’s Republic of China Ying Wang, School of Medicine, Jianghan University, Wuhan, 430056 People’s Republic of China Yong Liang, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing, 100085 People’s Republic of China Jie Zhang, Key Lab of Subtropical Agriculture and Environment, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, 430070 People’s Republic of China Journal Environmental Earth Sciences Online ISSN 1866-6299 Print ISSN 1866-6280

Beschreibung:    Landfill site selection is a complex and time-consuming process, which requires evaluation of several factors where many different attributes are taken into account. Decision makers always have some difficulties in making the right decision in the multiple attribute environments. After identifying candidate sites, these sites should be ranked using decision-making methods. This study applies Chang’s fuzzy AHP-based multiple attribute decision-making (MADM) method for selection of the best site of landfills based on a set of decision criteria. The Fuzzy Analytic Hierarchy Process (FAHP) was designed to make pairwise comparisons of selected criteria by domain experts for assigning weights to the decision criteria. Analytic Hierarchy Process (AHP) is used to make pairwise comparisons and assign weights to the decision criteria. It is easier for a decision maker to describe a value for an alternative by using linguistic terms and fuzzy numbers. In the fuzzy-based AHP method, the rating of each alternative was described using the expression of triangular fuzzy membership functions. Once the global weights of the criteria is calculated by AHP, they are incorporated into the decision matrices composed by decision maker and passed to fuzzy-AHP method which is used to determine preference order of siting alternatives. In this study, a computer program based on the Chang’s fuzzy method was also developed in MATLAB environment for ranking and selecting the landfill site. As an example of the proposed methodology, four different hypothetical areas were chosen and implemented to demonstrate the effectiveness of the program. By using this program, the precision was improved in comparison with traditional methods and computational time required for ranking and selecting the suitable landfill site was significantly reduced. Content Type Journal Article Pages 1-12 DOI 10.1007/s12665-011-1137-2 Authors Abdolhadi Nazari, Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, 424 Hafez Ave, 15875-4413 Tehran, Iran Mohammad Mehdi Salarirad, Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, 424 Hafez Ave, 15875-4413 Tehran, Iran Abbas Aghajani Bazzazi, Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, 424 Hafez Ave, 15875-4413 Tehran, Iran Journal Environmental Earth Sciences Online ISSN 1866-6299 Print ISSN 1866-6280

Beschreibung:    Heavy metal enrichment parity in sandy and shaly mechanic village (MV) soils was studied in order to explain the technical and economic imperatives of setting an environmentally friendly MV on either soil. Okigwe (shaly) and Nekede (sandy) mechanic village soils in the Imo River basin Nigeria were tested and compared. Spectroscopic analysis of the soil samples collected from three surface layers (L), where L1: 0–10 cm; L2: 10–20 cm and L3: 90–100 cm shows that Pb 〉 Cu 〉 Mn in the Okigwe MV, and Mn 〉 Pb 〉 Cu in the Nekede MV. Mean concentration of metals (mg kg −1 ) in Okigwe MV are Fe: 51,291 ± 18,148, Ni: 22 ± 4, Cd: 20 ± 3, Pb: 500 ± 513, Cu: 616 ± 369, Cr: 16 ± 9, and Mn: 378 ± 207. Similarly, Nekede MV has 22,101 ± 7,273 of Fe; 8 ± 0.8 of Ni; 11 ± 4 of Cd; 320 ± 122 of Pb; 265 ± 145 of Cu; 11 ± 2 of Cr; and 350 ± 191 of Mn. Pollution factor (Pf): Okigwe MV has 0.77, and Nekede has 0.68. Pollution degree: Okigwe MV is greater in L1 and L2, while Nekede is greater in L3, with greater potentials for Pb, and Mn mobility than the Okigwe. Both have similar trends of metal distribution, and significant correlation with their background values. Low clay-silt content in Nekede MV soil suggests low sorption capacity, whereas the high clay-silt content (47–64%) of the Okigwe soil suggests lower bioavailability. Infiltration basin is not recommended in a MV on sandy soil if water table is near surface. In such case, the MV must be moved to a location where water table is 〉37 m, or have clay-shale material transported to the site to form impervious layer base for detention basin. For groundwater safety and sustainability, shaly soils are most recommended for MVs so that detention basin could be economically used for storm water treatment. Content Type Journal Article Pages 1-10 DOI 10.1007/s12665-011-1122-9 Authors Michael A. Nwachukwu, Earth and Environ Studies, Montclair State University, Montclair, NJ, USA Huan Feng, Earth and Environ Studies, Montclair State University, Montclair, NJ, USA Jude Alinnor, School of Science, Federal University of Technology, Owerri, Nigeria Maureen Nwachukwu, GEOPROBE International Consultants Ltd, Owerri, Nigeria Journal Environmental Earth Sciences Online ISSN 1866-6299 Print ISSN 1866-6280

Beschreibung: Upcoming international events Content Type Journal Article Pages 1-6 DOI 10.1007/s12665-011-1138-1 Journal Environmental Earth Sciences Online ISSN 1866-6299 Print ISSN 1866-6280

Beschreibung:    The purpose of this study is to present a weighting method, integrating subjective weight with objective weight, for landslides susceptibility mapping based on geographical information system (GIS). First, the landslide inventory, aspect, slope, proximity to streams of drainage network, proximity to railway, proximity to road, topography, elevation, lithology, tectonic activity and annual precipitation, including their subclasses, were taken as independent landslide causal factors. Second, objective weights of the causal factors were calculated according to the landslide area density based on entropy weighting method, and key factors were selected according to the rank of the objective weights. Third, trapezoidal fuzzy number weighting approach was used to assess the sub-classes of each key factor. Finally, a case study was carried out in Guizhou province, China. A landslide susceptibility map was created using weighted linear combination model based on GIS. Using a predicted map of probability, the study area was classified into four categories of landslide susceptibility: low, moderate, moderate-high, and high. Content Type Journal Article Pages 1-10 DOI 10.1007/s12665-011-1148-z Authors Wei-Dong Wang, School of Civil Engineering and Architecture, Central South University, 22 South Shaoshan Road, Changsha, 410075 China Jing Guo, School of Civil Engineering and Architecture, Central South University, 22 South Shaoshan Road, Changsha, 410075 China Li-Gang Fang, School of Civil Engineering and Architecture, Central South University, 22 South Shaoshan Road, Changsha, 410075 China Xin-Sheng Chang, School of Civil Engineering and Architecture, Central South University, 22 South Shaoshan Road, Changsha, 410075 China Journal Environmental Earth Sciences Online ISSN 1866-6299 Print ISSN 1866-6280