ALBERT

Description: The objective of the study is to investigate the effect of released silicon (Si) and aluminum (Al) during the formation of volcanic ash soil on the content of Si in groundwater on Jeju Island. Volcanic ash soils in Jeju Island were formed from pyroclastic materials that originated from basalt. We sampled four profiles, including basaltic bedrock of each soil series with large variations in elevation (160–320 m) and mean annual precipitation (MAP; 1,800–2,600 mm). The soil and bedrock minerals were analyzed for weathering of volcanic ash soils related to mineralogical transformations and mobility of Si and Al. Andisols (above 2,000 mm MAP) were dominantly composed of allophane and gibbsite. In Andisols used in the study, 10–70% of Si was lost, whereas the amount of Al was relatively conserved. This is because Al forms Al-humus complex and Andisols contain allophane. In contrast, non-Andisols located at low altitude with lower than 1,800 mm MAP were enriched with considerable amounts of Si and Al, because non-Andisols have crystalline clay minerals and quartz. These results indicate that Andisols, which are widely distributed in Jeju Island, may play an important role in contributing to the high concentration of dissolved Si in the groundwater.

Description: Active land disturbance of soil and environments appears even in remote landscapes of tundra and forest tundra. Wildfires become a frequent factor of soil degradation and intensification of permafrost degradation, also affecting the global balance of carbon, especially content and distribution of polycyclic aromatic compounds. Mature unaffected by fire sandy-textured podzols soils were investigated in comparison with the same soil strongly affected by surface fire in the end of August 2016 in surroundings of the Pangody settlement, Nadym district, Yamal region. Data obtained showed an intensive morphological transformation of the topsoil layers, decreasing total organic matter and apparently increasing the humus enrichment by nitrogen. Wildfires also result in complete transformation of the fractional composition of the polycyclic aromatic compounds. The sum of PAHs increases intensively as well as benzo(a)pyrene content in soils. Therefore, soils of the cryolithozone become more faced to the wildfires during the last decades. Even one-time fire effect results in serious transformation of soil geochemical state.

Description: Landfills are major sources of environmental pollution. This study evaluated heavy metal concentrations in soils and plants around the closed Lumberstewart landfill in Bulawayo, Zimbabwe, to determine the pollution potential of a closed landfill and the risks they present to plants growing in this environment and surrounding communities. Soil samples were collected at depths of 0–30 cm, 30–60 cm, and 60–90 cm around the landfill and at a control site and characterized for various properties and concentrations of Cd, Cu, Cr, Fe, Ni, and Zn. Samples of Datura stramonium, collected from the same sites where soil samples were collected, were also analyzed for the same heavy metals. The soils were sandy, mostly acidic (5.01  Ni 〉 Cd with samples from around the landfill having higher concentrations than samples from the control site. Soil heavy metal enrichment was highest at a depth of 30–60 cm. Pollution load index (PLI) values indicated that all sites around the landfill were polluted (PLI 〉 1). Heavy metal transfer coefficient in Datura stramonium ranged between 0.0 and 209 with

Description: Different land use systems can have different soil properties. It is important to study the soil properties for wise use and sustainable management of land resources. This article reports the findings of a research conducted in Makwanpur district of Nepal, to determine and compare the selected physicochemical and hydrological properties of soil in forest, rainfed agriculture land, and grassland. These forest, agriculture land, and grassland represent tropical land use systems. Soil samples were collected from 0 to 30 cm depths of soil profile from nine randomly distributed pits dug in forest, grassland, and rainfed agriculture land in 2019. Soil samples were analyzed in the laboratory to determine the soil properties using standard methods. Bulk density, porosity, moisture content and infiltration, pH, total nitrogen, available potassium, and available phosphorus were quantified from the soils samples. It was found that the highest BD was found in the grassland (1.29 g/cm³) followed by the forest (1.23 g/cm³) and rainfed agriculture land (1.18 g/cm³). The highest porosity was found in rainfed agriculture land (55.50%) followed by the forest (53.74%) and grassland (51.63%). The highest MC was found in the grassland (26.94%) followed by the forest (10.17%) and rainfed agriculture land (9.92%). The mean cumulative infiltration amount was highest in the rainfed agriculture land (39.27 cm) followed by the forest (33.47 cm) and grassland (8.4 cm). The highest soil pH was found in the grassland (7.91) and the lowest pH (5.70) in the forest. The highest level of total nitrogen was found in rainfed agriculture land (0.121%), followed by the forest (0.106%) and grassland (0.096%). The highest level of available phosphorous was found in rainfed agriculture land (84.94 ppm), followed by the forest (67.76 ppm) and grassland (6.69). The highest level of available potassium was found in rainfed agriculture land (154.24 ppm), followed by the forest (84.49 ppm) and the grassland (44.71 ppm). Bulk density, porosity, and total nitrogen were not found to be significantly different and other soil properties were found to be significantly different between different land use systems. The contribution of farmers in maintaining soil properties on the farmlands is clearly reflected in the results, so their knowledge on soil management needs to be explored and adapted for wise use and sustainable management of other land use systems.

Description: Recent research findings imply that the slope aspect has a great impact on soil genesis and soil microclimate. The microclimate has a significant effect on the soil geobiochemical processes taking place in the soil. However, the slope aspect impact on soil properties has not been yet studied well in Ethiopia, particularly in the northern highlands. This research was initiated to link selected soil physicochemical properties with slope aspects under different land use practices. The research was conducted in Gumara-Maksegnit watershed located at the upper Lake Tana basin, Ethiopia. Four slope aspects, eastward (Ew), northward (Nw), southward (Sw), and westward (Ww), and three land use types at each slope aspect, cropland (Cl), forest land (Fl), and grazing land (Gl), were considered. In total, 36 undisturbed soil samples for bulk density and 36 disturbed soil samples for selected soil properties were collected. Soil particle size (texture), bulk density, electrical conductivity (EC), soil pH, available phosphorus (av. P), available potassium (av. K), total nitrogen (TN), and soil organic carbon (SOC) were analyzed. The resulting analyses showed no significant variation (p

Description: Despite the fact that mineral fertilizers are widely considered as a major option for addressing the crisis of nutrient depletion, their use among smallholder farmers is not adequate due to an escalating cost. Alternatively, nutrient-rich organic sources that are easily available to farmers are not widely promoted. Thus, this study was carried out in the research field of Wolaita Sodo University, Southern Ethiopia, to evaluate the effects of locally available organic nutrient sources and nitrogen (N) phosphorus (P) sulfur (S) fertilizer (19N-46P2O5-7S) on the productivity and economic performance of common bean. The organic materials used were Croton (Croton macrostachyus) and Erythrina (Erythrina brucei) at 2 : 1 ratio, respectively. The experiment was laid out in a randomized complete block design with three replications. Treatments for organic fertilizer (OF) were 0, 2.5, and 5 t·ha−1 and for NPS fertilizer were 0, 50, 100, and 150 kg·ha−1. Chemical composition analysis of organic materials showed high nutrient content where the amount varied from 4.7%–5.2% N, 11.07–18.6 mg/kg P, and 2.12%–3.07% K. Results on agronomic parameters revealed that the leaf area index, grain weight, number of pods per plant, dry matter per plant, and grain yield of haricot bean were significantly affected by both main and combined effects of NPS and OF fertilizers. The grain yield under integrated application of 150 kg NPS/ha and 2.5 t·OF/ha (4.16 t/ha) was significantly higher than that obtained from unfertilized crop (1.01 t/ha) by 312%. Additionally, it resulted in 34%, 31%, and 79% yield increment over the blanket dose (100 kg·NPS·ha−1), 2.5 t/ha and 5 t/ha, respectively. It was also noted that resource-poor farmers, compared to unfertilized crop, can get grain yield superior by 130% and 214% using sole OF at 2.5 and 5 t·ha−1, respectively. Furthermore, the highest economic benefit (27, 179.5EtB) was recorded from 150 kg NPS/ha + 2.5 t·OF/ha. The finding suggested that locally available organic materials of plant origin alone/integrated with NPS fertilizer are helpful for increased yield of haricot bean.

Description: The objectives of this study were to investigate effects of land use on accumulation of soil organic matter (SOM) in the soil profile (0–100 cm) and to determine pattern of SOM stock distribution in soil profiles. Soil samples were collected from five soil depths at 20 cm intervals from 0 to 100 cm under four adjacent land uses including forest, cassava, sugarcane, and paddy lands located in six districts of Maha Sarakham province in the Northeast of Thailand. When considering SOM stock among different land uses in all locations, forest soils had significantly higher total SOM stocks in 0–100 cm (193 Mg·C·ha−1) than those in cassava, sugarcane, and paddy soils in all locations. Leaf litter and remaining rice stover on soil surfaces resulted in a higher amount of SOM stocks in topsoil (0–20 cm) than subsoil (20–100 cm) in some forest and paddy land uses. General pattern of SOM stock distribution in soil profiles was such that the SOM stock declined with soil depth. Although SOM stocks decreased with depth, the subsoil stock contributes to longer term storage of C than topsoils as they are more stabilized through adsorption onto clay fraction in finer textured subsoil than those of the topsoils. Agricultural practices, notably applications of organic materials, such as cattle manure, could increase subsoil SOM stock as found in some agricultural land uses (cassava and sugarcane) in some location in our study. Upland agricultural land uses, notably cassava, caused high rate of soil degradation. To restore soil fertility of these agricultural lands, appropriate agronomic practices including application of organic soil amendments, return of crop residues, and reduction of soil disturbance to increase and maintain SOM stock, should be practiced.

Description: Phytoextraction is an effective and environment-friendly approach for remediation of soil polluted with toxic metals. Portulaca oleracea is a potential hyperaccumulator of Cr(VI) from polluted soil. In this study, the effect of soil organic content, pH, and sulphate concentration on phytoextraction of Cr(VI) using Portulaca oleracea was investigated. Seedlings of Portulaca oleracea were grown in soils with (i) three organic content compositions, (ii) six levels of pH, and (iii) six concentrations of sulphate salts; all were irrigated with Cr(VI) solutions at 200 ppm concentration. Chromium concentration in different tissues of plants was monitored under the variant conditions. Results indicated that the uptake of Cr(VI) by Portulaca oleracea is favoured at (i) low organic content soil (0.42%), (ii) slightly alkaline pH range (∼8), and (iii) with sulphate concentration in the range of 300–600 ppm.

Description: The use of silver in various spheres of life and production leads to an increase in environmental pollution, including soil. At the same time, the environmental consequences of silver pollution of soils have been studied to a much lesser extent than those of other heavy metals. The aim of this study is to estimate silver ecotoxicity using the soil state biological indicators. We studied soils that are significantly different in resistance to heavy metal pollution: ordinary chernozem (Haplic Chernozems, Loamic), sierosands (Haplic Arenosols, Eutric), and brown forest acidic soil (Haplic Cambisols, Eutric). Contamination was simulated in the laboratory. Silver was introduced into the soil in the form of nitrate in doses of 1, 10, and 100 mg/kg. Changes in biological parameters were assessed 10, 30, and 90 days after contamination. Silver pollution of soils in most cases leads to deterioration of their biological properties: the total number of bacteria, the abundance of bacteria of the genus Azotobacter, the activity of enzymes (catalase and dehydrogenases), and the phytotoxicity indicators decrease. The degree of reduction in biological properties depends on the silver concentration in the soil and the period from the contamination moment. In most cases, there is a direct relationship between the silver concentration and the degree of deterioration of the studied soil properties. The silver toxic effect was most pronounced on the 30th day after contamination. In terms of their resistance to silver pollution, the studied soils are in the following order: ordinary chernozem 〉 sierosands ≥ brown forest soil. The light granulometric composition of sierosands and the acidic reaction of the environment of brown forest soils, as well as the low content of organic matter, contribute to high mobility and, consequently, high ecotoxicity of silver in these soils. The regional maximum permissible concentration (rMPC) of silver in ordinary chernozem (Haplic Chernozems, Loamic) is 4.4 mg/kg, in sierosands (Haplic Arenosols, Eutric) 0.9 mg/kg, and in brown forest soils (Haplic Cambisols, Eutric) 0.8 mg/kg.