ALBERT

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Computational Physics〈/p〉 〈p〉Author(s): Maxim Rakhuba, Alexander Novikov, Ivan Oseledets〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Such problems as computation of spectra of spin chains and vibrational spectra of molecules can be written as 〈em〉high-dimensional eigenvalue problems〈/em〉, i.e., when the eigenvector can be naturally represented as a multidimensional tensor. Tensor methods have proven to be an efficient tool for the approximation of solutions of high-dimensional eigenvalue problems, however, their performance deteriorates quickly when the number of eigenstates to be computed increases. We address this issue by designing a new algorithm motivated by the ideas of 〈em〉Riemannian optimization〈/em〉 (optimization on smooth manifolds) for the approximation of multiple eigenstates in the 〈em〉tensor-train format〈/em〉, which is also known as matrix product state representation. The proposed algorithm is implemented in TensorFlow, which allows for both CPU and GPU parallelization.〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Computational Physics〈/p〉 〈p〉Author(s): Chen Liu, Florian Frank, Faruk O. Alpak, Béatrice Rivière〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Permeability estimation of porous media from directly solving the Navier–Stokes equations has a wide spectrum of applications in petroleum industry. In this paper, we utilize a pressure-correction projection algorithm in conjunction with the interior penalty discontinuous Galerkin scheme for space discretization to build an incompressible Navier–Stokes simulator and to use this simulator to calculate permeability of real rock samples. The proposed method is accurate, numerically robust, and exhibits the potential for tackling realistic problems.〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Contaminant Hydrology, Volume 226〈/p〉 〈p〉Author(s): Mehrdad Bastani, Thomas Harter〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Nitrate in drinking water may cause serious health problems for consumers. Agricultural activities are known to be the main source of groundwater nitrate contaminating rural domestic and urban public water supply wells in farming regions. Management practices have been proposed to reduce the amount of nitrate in groundwater, including improved nutrient management practices and “pump and fertilize” with nitrate-affected irrigation wells. Here, we evaluate the feasibility and long-term impacts of agricultural managed aquifer recharge (Ag-MAR) in the source area of public water supply wells. A numerical model of nitrate fate and transport was developed for the Modesto basin, part of California's Central Valley aquifer system. The basin is representative of semi-arid agricultural regions around the world with a diversity of crop types, overlying an unconsolidated sedimentary aquifer system. A local public supply well in an economically disadvantaged community surrounded by farmland was the focus of this study. Model scenarios implemented include business as usual, alternative low-impact crops, and Ag-MAR in the source area of the public supply well. Alternative nutrient management and recharge practices act as remediation tools in the area between farmland and the public supply well. Improved agricultural source area management practices are shown to be an effective tool to maintain or even enhance groundwater quality in the targeted supply well while remediating ambient groundwater.〈/p〉 〈p〉Best results are obtained when lowering nitrate load while also increasing recharge in the source area simultaneously. This scenario reduced nitrate in the supply well's drinking water by 80% relative to the business as usual scenario. It also remediated ambient groundwater used by domestic wells between the source area farmlands and the supply well and showed 60% more reduction of nitrate after 60 years of application. Increasing recharge led to shorter initial response time (five years) and showed the most sustainable impact. Our analysis further suggests that Ag-MAR in a highly discontinuous, wide-spread pattern leads to slow water quality response and may not yield sufficient water quality improvements.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Computational Physics〈/p〉 〈p〉Author(s): Mustapha Malek, Nouh Izem, M. Shadi Mohamed, Mohammed Seaid, Omar Laghrouche〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉An efficient partition of unity finite element method for three-dimensional transient diffusion problems is presented. A class of multiple exponential functions independent of time variable is proposed to enrich the finite element approximations. As a consequence of this procedure, the associated matrix for the linear system is evaluated once at the first time step and the solution is obtained at subsequent time step by only updating the right-hand side of the linear system. This results in an efficient numerical solver for transient diffusion equations in three space dimensions. Compared to the conventional finite element methods with 〈em〉h〈/em〉-refinement, the proposed approach is simple, more efficient and more accurate. The performance of the proposed method is assessed using several test examples for transient diffusion in three space dimensions. We present numerical results for a transient diffusion equation with known analytical solution to quantify errors for the new method. We also solve time-dependent diffusion problems in complex geometries. We compare the results obtained using the partition of unity finite element method to those obtained using the standard finite element method. It is shown that the proposed method strongly reduces the necessary number of degrees of freedom to achieve a prescribed accuracy.〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Computational Physics〈/p〉 〈p〉Author(s): Lahbib Bourhrara〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This document presents a new numerical scheme dealing with the Boltzmann transport equation. This scheme is based on the expansion of the angular flux in a truncated spherical harmonics function and the discontinuous finite element method for the spatial variable. The advantage of this scheme lies in the fact that we can deal with unstructured, non-conformal and curved meshes. Indeed, it is possible to deal with distorted regions whose boundary is constituted by edges that can be either line segments or circular arcs or circles. In this document, we detail the derivation of the method for 2D geometries. However, the generalization to 2D extruded geometries is trivial.〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Contaminant Hydrology〈/p〉 〈p〉Author(s): Héloïse A.A. Thouement, Tomasz Kuder, Timo J. Heimovaara, Boris M. Van Breukelen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Back-diffusion of chlorinated ethenes (CEs) from low-permeability layers (LPLs) causes contaminant persistence long after the primary spill zones have disappeared. Naturally occurring degradation in LPLs lowers remediation time frames, but its assessment through sediment sampling is prohibitive in conventional remediation projects. Scenario simulations were performed with a reactive transport model (PHT3D in FloPy) accounting for isotope effects associated with degradation, sorption, and diffusion, to evaluate the potential of CSIA data from aquifers in assessing degradation in aquitards. The model simulated a trichloroethylene (TCE) DNAPL and its pollution plume within an aquifer-aquitard-aquifer system. Sequential reductive dechlorination to ethene and sorption were uniform in the aquitard and did not occur in the aquifer. After 10 years of loading the aquitard through diffusion from the plume, subsequent source removal triggered release of TCE by back-diffusion. In the upper aquifer, during the loading phase, δ〈sup〉13〈/sup〉C-TCE was slightly enriched (up to 2‰) due to diffusion effects stimulated by degradation in the aquitard. In the upper aquifer, during the release phase, (i) source removal triggered a huge δ〈sup〉13〈/sup〉C increase especially for higher CEs, (ii) moreover, downstream decreasing isotope ratios (caused by downgradient later onset of the release phase) with temporal increasing isotope ratios reflect aquitard degradation (as opposed to downstream increasing and temporally constant isotope ratios in reactive aquifers), and (iii) the carbon isotope mass balance (CIMB) enriched up to 4‰ as lower CEs (more depleted, less sorbing) have been transported deeper into the aquitard. Thus, enriched CIMB does not indicate oxidative transformation in this system. The CIMB enrichment enhanced with more sorption and lower aquitard thickness. Thin aquitards are quicker flushed from lower CEs leading to faster CIMB enrichment over time. CIMB enrichment is smaller or nearly absent when daughter products accumulate. Aquifer CSIA patterns indicative of aquitard degradation were similar in case of linear decreasing rate constants but contrasted with previous simulations assuming a thin bioactive zone. The Rayleigh equation systematically underestimates the extent of TCE degradation in aquifer samples especially during the loading phase and for conditions leading to long remediation time frames (low groundwater flow velocity, thicker aquitards, strong sorption in the aquitard). The Rayleigh equation provides a good and useful picture on aquitard degradation during the release phase throughout the sensitivity analysis. This modelling study provides a framework on how aquifer CSIA data can inform on the occurrence of aquitard degradation and its pitfalls.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Ocean Modelling, Volume 140〈/p〉 〈p〉Author(s): Oleg Druzhinin, Yuliya Troitskaya, Wu-ting Tsai, Po-chen Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study is concerned with direct numerical simulation (DNS) of turbulent air flow over a waved water surface. Three-dimensional, turbulent Couette flow is considered in DNS as a model of a constant-flux layer in the marine atmospheric surface layer. Two-dimensional stationary waves at the water surface are prescribed and assumed to be unaffected by the air-flow. We consider capillary-gravity water surface waves and are interested in the influence of “parasitic” capillary ripples riding on the carrier, energy-containing waves, on the properties of the air-flow. The surface waves are prescribed and considered to be stationary, the capillaries being in phase with the carrier wave. The surface elevations spectra are also prescribed and mimicking stationary capillaries riding on Stokes waves observed in a 2D numerical simulation of water-surface capillary-gravity waves by Hung & Tsai (2009). The bulk air velocity and the carrier water surface waves lengths are considered in our DNS in the range of 3 to 5 m/s and 3 to 7 cm, respectively. Under these conditions, the capillaries are found to be submerged within the viscous sublayer of the atmospheric boundary layer. Our DNS results show that although the flow fields are characterized by instantaneous separations of the boundary layer, the ensemble (wave-phase) averaged flow fields are non-separating and well predicted by a quasilinear theoretical model. We find also that capillaries mitigate the development of coherent (horse-shoe) vortex structures as compared to the no-ripples flow-case. We further use DNS results and quasilinear model formulation to parameterize the water surface roughness height in terms of critical layer thickness and the amplitude of a dominant, energy-containing harmonic of the water surface elevation spectrum.〈/p〉〈/div〉 〈/div〉

Description: ABSTRACT Atmospheric models such as the Weather Research and Forecasting (WRF) model provide a tool to evaluate the behavior of regional hydrological cycle components, including precipitation, evapotranspiration, soil water storage and runoff. Recent model developments have focused on coupled atmospheric‐hydrological modeling systems, such as WRF‐Hydro, in order to account for subsurface, overland, and river flow and potentially improve the representation of land‐atmosphere interactions. The aim of this study is to investigate the contribution of lateral terrestrial water flow to the regional hydrological cycle, with the help of a joint soil‐vegetation‐atmospheric water tagging (SVA‐TAG) procedure newly developed in the so‐called WRF‐tag and WRF‐Hydro‐tag models. An application of both models for the high precipitation event on 15 August 2008 in the German and Austrian parts of the upper Danube river basin (94,100 km2) is presented. The precipitation that fell in the basin during this event is considered as a water source, is tagged and subsequently tracked for a 40 month‐period until December 2011. At the end of the study period, in both simulations, approximately 57% of the tagged water has run off, while 41% has evaporated back to the atmosphere, including 2% that has recycled in the upper Danube river basin as precipitation. In WRF‐Hydro‐tag, the surface evaporation of tagged water is slightly enhanced by surface flow infiltration, and slightly reduced by subsurface lateral water flow in areas with low topography gradients. This affects the source precipitation recycling only in a negligible amount.

Description: Abstract Snow acts as a vital source of water especially in areas where streamflow relies on snowmelt. The spatio‐temporal pattern of snow cover has tremendous value for snowmelt modeling. Instantaneous snow extent can be observed by remote sensing. Cloud cover often interferes. Many complex methods exist to resolve this, but often have requirements which delay the availability of the data and prohibit its use for real‐time modeling. In this research, we propose a new method for spatially modeling snow cover throughout the melting season. The method ingests multiple years of MODIS snow cover data and combines it using principal component analysis (PCA) to produce a spatial melt‐pattern model. Development and application of this model relies on the inter‐annual recurrence of the seasonal melting pattern. This recurrence has long been accepted as fact, but to our knowledge has not been utilized in remote sensing of snow. We develop and test the model in a large watershed in Wyoming using 17 years of remotely sensed snow cover images. When applied to images from two years that were not used in its development, the model represents snow covered area with accuracy of 84.9‐97.5% at varied snow covered areas. The model also effectively removes cloud cover if any portion of the interface between land and snow is visible in a cloudy image. This new PCA method for modeling the inter‐annually recurring spatial melt pattern exclusively from remotely sensed images possesses its own intrinsic merit, in addition to those associated with its applications.

Description: Abstract The development of the unconventional gas and CO2 sequestration is moving to deep formations. Because of the small flow pathways in the matrix, the Knudsen number might be high even though the gas is dense. In fact, due to the relatively high pressure at in situ conditions, gas flow in microfractures usually manifests a strong slip and nonideal gas effects. Therefore, understanding the coupling mechanism of these two on gas flow in rough‐walled microfractures is required to accurately model subsurface flow behavior. In this study, pressure‐driven gas flow in rough‐walled microfracture is analyzed in depth. Starting from the local governing equations for gas flow, a local flow model that includes gas slip and nonideal gas effects is derived by solving the Stokes equation with a first‐order slip boundary condition. Focusing at the representative elementary volume scale, the upscaled solutions to gas flow in a fracture with sinusoidal surface are derived to obtain the apparent permeability. The impact of nonideal gas effects, fracture roughness and aperture, and the tangential momentum accommodation coefficient on CH4 and CO2 flow is analyzed. The results show that fracture roughness introduces a high degree of heterogeneity in gas flow. At in situ conditions effects of gas slip, fracture roughness and tangential momentum accommodation coefficient on gas flow are reduced. The ideal gas law is capable of estimating CH4 flow to some extent. However, it fails to estimate CO2 flow in microfractures.

Description: Abstract In recent years, climatology, variability, hydrological impact, and climatic drivers of atmospheric rivers (ARs) are widely explored based on various AR identification algorithms. Different algorithms, varying in their tracing variables, thresholds, and geometric metrics criteria, will introduce uncertainty in further study of AR. Herein, a novel AR identification algorithm is proposed to address some current limitations. A coupled quantile and Gaussian kernel smoothing technique is proposed to make a balance in capturing the spatiotemporal variation of integrated water vapor transport climatology and avoiding largely biased estimation. In spite of variety of AR shape, orientation, and curvature, more reliable AR metrics (e.g., length and width) can be calculated based on the generated smooth AR trajectory, which is realized by modifying and integrating the concepts of local regression and K‐nearest neighbors. An unprecedented and novel metric (i.e., turning angle series) is delivered to quantify AR curvature, serves as the key to distinguish tropical cyclone‐like features, which often indicate occurrences of tropical cyclones. It also bridges ARs to their associated atmospheric circulation patterns. A pilot application of the algorithm is presented to identify persistent AR events related to flood triggering extreme precipitation sequences in the Yangtze River Basin (YRB). A dominating AR route, which connects Arabian Sea, Bay of Bengal, South China Sea, to Southeast China and YRB, terminates in the North Pacific, is found principal to the flood triggering extreme precipitation sequences in the YRB. In addition, this algorithm is extensible to other regions, even global domain.

Description: 〈p〉Publication date: July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Transportation Research Part F: Traffic Psychology and Behaviour, Volume 64〈/p〉 〈p〉Author(s): Kayla Fleskes, David S. Hurwitz〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉One proposed benefit of automated vehicles (AVs) is their potential to mitigate the occurrence of serious crashes due to human error or poor decision making while driving. However, there are still many concerns associated with the use of SAE Level 3 AVs, which require intervention by a human driver after a take-over request (TOR). These concerns intensify when vulnerable road users, such as bicyclists, are introduced to the driving environment. The objective of this research was to investigate how human drivers of AVs interact with bicyclists during a right-turn maneuver after receiving a TOR. Changes in driver performance, including visual attention and crash avoidance behavior, were measured by using a high-fidelity driving simulator, with 43 participants each completing 18 right-turn maneuvers. Three independent variables were studied: the bicyclist’s proximity to the intersection, the driver’s proximity from the intersection when the TOR was received, and the driver’s engagement in a distracting secondary task (a game on a tablet). In general, the results showed that the introduction of the secondary task led to decreased driver performance with respect to time-to-collision and the time that it took a driver to first identify the bicyclist on the roadway. When given more time to react before the intersection, drivers generally had safer interactions with the bicyclist.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S136984781830411X-ga1.jpg" width="426" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary International〈/p〉 〈p〉Author(s): Brian F. Codding, Adrian R. Whitaker, Nathan E. Stevens〈/p〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary Science Reviews, Volume 218〈/p〉 〈p〉Author(s): Athanassios Athanassiou, Alexandra A.E. van der Geer, George A. Lyras〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The Eastern Mediterranean islands, most of which belong to the Aegean archipelago, have a complex biogeographic history, which puts its stamp on their fauna and flora. A now extinct but most important faunal component, in terms of geographic spread and taxonomic diversity, are the elephants. The Eastern Mediterranean islands are particularly rich in Pleistocene endemic elephant localities, which preserve samples of extinct endemic populations. These were either descendants of the European straight-tusked elephant 〈em〉Palaeoloxodon antiquus〈/em〉 or the Southern mammoth, 〈em〉Mammuthus meridionalis〈/em〉. Their presence, history and palaeobiogeography has been documented only for Cyprus, Crete, Kasos, Rhodes, Tilos, Kýthera, Naxos, and Delos. For six other islands only anecdotal references exist in the literature: Kálymnos, Astypálaia, Milos, Sériphos, Kýthnos and Paros. Here, we provide an update on previously published specimens and taxa, describe previously undescribed specimens that were relocated in museum collections, as well as recently excavated specimens, and put these in the context of island palaeobiogeography. We conclude that dwarf elephants, endemic to their palaeo-island, lived on the islands of palaeo-Cyclades, Astypálaia, Crete, Kasos–Kárpathos–Saría, Tilos, Rhodes and Cyprus, whereas the elephants from Kephallenía, Kálymnos and Kýthera are indistinguishable on the species level from mainland 〈em〉Palaeoloxodon antiquus〈/em〉. Elephant fossils of unresolved taxonomic status are reported from five present-day islands. The Eastern Mediterranean endemic elephants likely derived from separate and independent colonisation events from the mainland. No island supported more than one proboscidean species at any time. We found that isolation had no effect on the degree of dwarfism, but that there exists a threshold of about 6–10 km distance between the island and the mainland, below which no dwarfism evolved, likely as a result of genetic contact with the mainland population. We also found that although island area is correlated with the degree of dwarfism in elephants, other factors, such as the level of interspecific competition, may limit this degree.〈/p〉〈/div〉 〈/div〉

Description: Butterfly numbers have dropped by one third in the US over 20 years because of climate change and habitat destruction – and other insects may be declining too

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Remote Sensing of Environment〈/p〉 〈p〉Author(s): Julie A. Fortin, Jeffrey A. Cardille, Elijah Perez〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉The ongoing march toward freely available, highly pre-processed satellite imagery has given both researchers and the public unprecedented access to a vast and varied data stream teeming with potential. Among many sources, the multi-decade Landsat archive is certainly the best known, but legacy and current data from other sensors is available as well through the USGS data portals: these include CBERS, ASTER, and more. Though the particular band combinations or non-global missions have made their integration into analyses more challenging, these data, in conjunction with the entire Landsat record, are available to contribute to multi-decade surveys of land-cover change.〈/p〉 〈p〉With the goal of tracing forest change through time near the Roosevelt River in the state of Mato Grosso, Brazil, we used BULC and Google Earth Engine to fuse information from 13 space-borne imagers capturing 140 images spanning 45 years. With high accuracy, the resulting time series of classifications shows the timing and location of land-use/land-cover change—both deforestation and regrowth—at sub-annual time scales. Accuracy estimates showed that the synthesized BULC classification time series was better than nearly all of the single-day image classifications, covering the entire study area at sub-annual frequency while reducing the impact of clouds and most unwanted noise as it fused information derived from a wide array of imaging platforms. The time series improved and gradually sharpened as the density of observations increased in recent decades, when there were three or more clear, higher-resolution views of a pixel annually from any sensor combination. In addition to detailing the methodology and results of multi-source data fusion with the BULC approach, this study raises timely points about integrating information from early satellite data sources and from sensors with footprints smaller than Landsat's. There are decades of research deriving sensor-specific techniques for classifying land use and land cover from a single image in a variety of settings. The BULC approach leverages the many successes of single-sensor research and can be used as a straightforward, complementary tool for blending many good-quality mapped classifications from disparate sources into a coherent, high-quality time series.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 8 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary International〈/p〉 〈p〉Author(s): Xiaolin Ren, Duowen Mo, Michael Storozum, Ximena Lemoine, Yanyan Yu, Wanfa Gu, Xingshan Lei, Jiaqiang Zhang, Jianqing Lü, Tristram R. Kidder〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Archaeologists have focused on the social conditions surrounding the development of urbanism around the world, however the environmental impact of these ancient cities remains unclear. In this paper, we present palynological data from the early Bronze Age city of Dongzhao, Henan Province, China. Our data indicate that vegetation change and the development of early urban settlements are closely linked, with the advent of urban development significantly accelerating deforestation and altering the composition of local vegetation communities. The pollen record from Dongzhao provides new evidence to support the claim that urban expansion, coupled with a drying climate and the expansion of agriculture, dramatically reconfigured the landscapes of Bronze Age China.〈/p〉〈/div〉 〈/div〉

Description: Chlamydia may be able to spread through the gut after oral sex and go on to cause rectal infections, according to a study of heterosexual men

Description: David Attenborough says the UK must take radical action to meet its climate change targets, but politicians must make efforts to keep the public on side too

Description: Instagram will ask users to think again if they are about to post something that could be considered offensive and early tests suggest it could work, says the firm

Description: Virgin Galactic is to become the first publicly traded company for human space travel after it announced a merger with a major investment group

Description: A therapy that uses RNA interference to treat the rare condition hereditary transthyretin-mediated amyloidosis has been approved for NHS use in England

Description: Ashley Spindler's machine-learning code is slowly teaching itself to simulate and identify distant galaxies – giving her time for hobbies like making chain-mail armour

Description: A computer program called the Ramanujan Machine is generating mathematical conjectures for constants like π and e, just like the legendary Indian mathematician

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Computers & Geosciences, Volume 132〈/p〉 〈p〉Author(s): T. Carlotto, P.L.B. Chaffe〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Streamflow recession analysis is crucial for understanding how catchments release water in periods of drought and therefore is important for water resources planning and management. Despite there being several theories on how to model recession curves, few studies compare the different approaches to that problem. In this work, we developed the Master Recession Curve Parameterization tool (MRCPtool), which brings together a set of automated methods for the analysis of recession periods based only on streamflow data. The methods include: (i) hydrograph separation using numerical filters; (ii) automatic extraction of recession periods; (iii) creation of the MRC with the matching strip method; (iv) creation of the MRC for different flow classes defined from the flow duration curve; (v) analysis of flow recession rates 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" altimg="si1.svg"〉〈mrow〉〈mo〉(〈/mo〉〈mo linebreak="goodbreak" linebreakstyle="after"〉−〈/mo〉〈mi〉d〈/mi〉〈mi〉Q〈/mi〉〈mo〉∕〈/mo〉〈mi〉d〈/mi〉〈mi〉t〈/mi〉〈mo〉)〈/mo〉〈/mrow〉〈/math〉 as a function of flow 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" altimg="si2.svg"〉〈mrow〉〈mo〉(〈/mo〉〈mi〉Q〈/mi〉〈mo〉)〈/mo〉〈/mrow〉〈/math〉 and (vi) creation of the MRC from simulated recession curves with different analytical approaches, including linear and nonlinear models. The MRCPtool contains a graphical user interface developed in MATLAB software that facilitates the analysis of streamflow datasets. Finally, we present an example application of the MRCPtool using a streamflow dataset of 44 years. The MRCPtool is an open source tool that can be downloaded from the site: 〈a href="http://www.labhidro.ufsc.br/static/software/MRCPtool.rar" target="_blank"〉http://www.labhidro.ufsc.br/static/software/MRCPtool.rar〈/a〉.〈/p〉〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Advances in Water Resources, Volume 131〈/p〉 〈p〉Author(s): Shaokun He, Shenglian Guo, Kebing Chen, Lele Deng, Zhen Liao, Feng Xiong, Jiabo Yin〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The optimal impoundment operation of cascade reservoirs can dramatically improve the utilization of water resources. However, their complex non-convexity and computational costs pose challenges to optimal hydroelectricity output and limit further development of joint operation within larger-scale cascade reservoirs. In recent decades, parallel dynamic programming (PDP) has emerged as a means of alleviating the ‘curse of dimensionality’ in the mid-long term reservoir operation with more involved computing processors. But it still can't effectively solve the daily impoundment operation of more than three reservoirs. Here, we propose a novel method called importance sampling-PDP (IS-PDP) algorithm in which the merits of PDP are integrated with importance sampling and successive approximation strategy. Importance sampling is first used to construct the state vectors of each period by introducing ‘Manhattan distance’ in the discrete state space. Then the PDP recursive equation is used to find an improved solution during the iteration. The IS-PDP method is tested to optimize hydropower output for the joint operation of an 11-reservoir system located in the upper Yangtze River basin of China after establishing impoundment operation by advancing impoundment timings and rising water levels. We find that our methodology could effectively deal with the ‘curse of dimensionality’ for such mega reservoir systems and make better use of water resources in comparison to the Standard Operation Policy (SOP). Given its computational efficiency and robust convergence, the methodology is an attractive alternative for non-convex operation of large-scale cascade reservoirs.〈/p〉〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Ultramicroscopy, Volume 206〈/p〉 〈p〉Author(s): P. Kükelhan, T. Hepp, S. Firoozabadi, A. Beyer, K. Volz〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Quantitative scanning transmission electron microscopy (STEM) is a powerful tool for the characterization of nano-materials. Absolute composition determination for ternary III–V semiconductors by direct comparison of experiment and simulation is well established. Here, we show a method to determine the composition of quaternary III–V semiconductors with two elements on each sub lattice from the intensities of one STEM image. As an example, this is applied to (GaIn)(AsBi). The feasibility of the method is shown in a simulation study that also explores the influence of detector angles and specimen thickness. Additionally, the method is applied to an experimental STEM image of a (GaIn)(AsBi) quantum well grown by metal organic vapour phase epitaxy. The obtained concentrations are in good agreement with X-ray diffraction and photoluminescence results.〈/p〉〈/div〉

Description: Abstract High‐intensity precipitation represents a threat for several regions of the world because of the related risk of natural disasters (e.g., floods and landslides). This work focuses on low‐level precipitation enhancement that occurs in the cloud warm layer and has been observed in relation to collision‐coalescence (CC) leading to flash floods and extreme rainfall events in tropical and temperate latitudes. Specifically, signatures of precipitation enhancement (referred to as CC‐dominant precipitation) are investigated in the observations from the Global Precipitation Measurement (GPM) core mission Dual‐frequency Precipitation Radar (DPR) over the central/eastern Contiguous United States (CONUS) during June 2014 – May 2018. A classification scheme for CC‐dominant precipitation, developed for dual‐polarization S‐band radar measurements and applied in a previous work to X‐band radar observations in complex terrain, is used as a benchmark. The scheme is here applied to the GPM ground validation dataset that matches ground‐based radar observations across CONUS to space‐borne DPR retrievals. The occurrence of CC‐dominant precipitation is documented and the corresponding signatures of CC‐dominant precipitation at Ku‐ and Ka‐band are studied. CC‐dominant profiles show distinguishing features when compared to profiles not dominated by CC, e.g., characteristic vertical slopes of reflectivity at Ku‐ and Ka‐band in the liquid layer, lower freezing level height, and shallower ice layer, which are linked to environmental conditions driving the peculiar CC microphysics. This work aims at improving satellite quantitative precipitation estimation, particularly GPM retrievals, by targeting CC development in precipitation columns. This article is protected by copyright. All rights reserved.

Description: Air pollution from human activities in China has decreased the potential output of solar panels by 13 per cent between 1960 and 2015, resulting in loss electricity generation and revenue

Description: Some male infertility may be down to the damage sperm experiences as it matures and enters semen – so taking immature sperm directly from the testes could help

Description: Science fiction books like ZED and This Is How You Lose the Time War use exhilarating writing to create worlds that seem eerily similar to ours, says Helen Marshall in her monthly sci-fi column

Description: Jodrell Bank Observatory, a world-leading centre for radio astronomy in the UK, has been added to the UNESCO World Heritage List

Description: 〈p〉Publication date: August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 ISPRS Journal of Photogrammetry and Remote Sensing, Volume 154〈/p〉 〈p〉Author(s): 〈/p〉

Description: A hack that accessed the personal data of around half a million British Airways customers has earned the firm a record £183 million fine

Description: 〈p〉Publication date: July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Ocean Modelling, Volume 139〈/p〉 〈p〉Author(s): 〈/p〉

Description: Abstract A storage‐discharge relation tells us how discharge will change when new water enters a hydrologic system, but not which water is released. Does an incremental increase in discharge come from faster turnover of older water already in storage? Or are the recent inputs rapidly delivered to the outlet, ‘short‐circuiting’ the bulk of the system? Here I demonstrate that the concepts of storage‐discharge relationships and transit time distributions can be unified into a single relationship that can usefully address these questions: the age‐ranked storage‐discharge relation. This relationship captures how changes in total discharge arise from changes in the turn‐over rate of younger and older water in storage, and provides a window into both the celerity and velocity of water in a catchment. This leads naturally to a distinction between cases where an increase in total discharge is accompanied by an increase (old water acceleration), no change (old water steadiness), or a decrease in the rate of discharge of older water in storage (old water suppression). The simple theoretical case of a power‐law age‐ranked storage‐discharge relations is explored to illustrate these cases. Example applications to data suggest that the apparent presence of old water acceleration or suppression is sensitive to the functional form chosen to fit to the data, making it difficult to draw decisive conclusions. This suggests new methods are needed that do not require a functional form to be chosen, and provide age‐dependent uncertainty bounds.

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 World Development, Volume 123〈/p〉 〈p〉Author(s): Adriana Camacho, Emily Conover〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Small-scale farmers in developing countries often make production and sale decisions based on imprecise, informal, and out-of-date sources of information, such as family, neighbors, or tradition. Lack of timely and accurate information on climate and prices can lead to inefficiencies in the production, harvesting, and commercialization of agricultural products, which in turn can affect farmers’ revenues and well-being. We did a Randomized Controlled Trial (RCT) experiment with 500 small-scale farmers in a rural area of Colombia where there is nearly full mobile phone usage and coverage. Treated farmers received around 8 text messages per week with prices in the main markets for crops grown in the region, and customized weather forecasts. Compared to a control group, we find that treated farmers were more likely to report that text messages provide useful information for planting and selling, and more likely to always read their messages, indicating an increase in appreciation and use of this type of technology. We also found heterogeneous effects by farmer size. Smaller farmers try to make use of the intervention by planting more crops for which they have price information. Larger farmers seek new markets and increase conversations with other producers. Despite these positive effects, we do not find a significant difference in farmers reporting a price, price differential with the market price, or sale prices received. Our results indicate that farmers are amenable to learning and using new technologies, but that the introduction of these technologies do not always translate into short-run welfare improvements for them. Given the increased interest in incorporating information and communication technologies into agriculture, our findings indicate that prior to a large-scale implementation it is necessary to better understand what prevents farmers from more directly profiting from this new information.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Remote Sensing of Environment, Volume 232〈/p〉 〈p〉Author(s): Yue Ma, Nan Xu, Jinyan Sun, Xiao Hua Wang, Fanlin Yang, Song Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Currently, 〈em〉in-situ〈/em〉 data and the time duration of altimeter data are limitations in calculating the water level and water volume of lakes and reservoirs from remotely sensed data. A novel method is proposed to estimate the temporal change in water levels and water volumes for lakes with only remotely sensed data. First, the surface profiles, including the ground and the underwater bottom, were extracted from the MABEL (Multiple Altimeter Beam Experimental Lidar) photon-counting lidar raw data via a new surface detecting algorithm. Second, the lake boundaries between land and water in different years were identified using a thresholding method based on the annual median Landsat composite. Third, water levels were calculated by matching the lidar surface profiles with the lake boundaries based on the nearby georeferenced coordinates. Finally, the water volumes in different years were estimated via the contours (i.e., lake boundaries) with different elevations. Lake Mead was selected as the study area, which is the largest reservoir in the United States in terms of water capacity. With only one day measuring lidar points in February 2012 and over 20 years of Landsat images (from 1987 to 2007), the water levels and water volumes in different years were estimated and compared with the 〈em〉in-situ〈/em〉 data. Our results performed well in accordance with the 〈em〉in-situ〈/em〉 measurements; the R-square of the water levels and water volumes were both over 0.99; the RMSE of the interannual variations of water levels and water volumes were 0.96 m and 0.31 km〈sup〉3〈/sup〉, respectively. The MABEL was used as a technology demonstrator for the satellite photon-counting laser altimeter and had similar data to the ICESat-2 dataset. Future ICESat-2 datasets will broaden this method to estimate water volumes for remote lakes from the 1980s, where no 〈em〉in-situ〈/em〉 data are available (such as the Tibetan Plateau and polar regions with thousands of remote and wild lakes), which could not be achieved in previous studies.〈/p〉〈/div〉 〈/div〉

Description: Sight Machine, an AI project at the Barbican, shows how the algorithms used in techniques like facial detection capture the performance of a string quartet

Description: Abstract Aims As global temperatures rise, the survival of many species may hinge on whether they can shift their climatic niches quickly enough to avoid extinction. Previous analyses among species and populations suggest that species’ niches change far slower than rates of projected climate change. However, it is unclear how quickly niches can change over the timeframe most relevant to global warming (decades instead of thousands or millions of years). Here, we use data from introduced species to assess how quickly climatic niches can change over decadal timescales. Location Global. Methods We analyse climatic data from 76 reptile and amphibian species introduced into the USA. We test for a relationship between species climatic‐niche values in their native and introduced ranges. We also quantify niche shifts in introduced populations relative to their native ranges and the rate of change associated with these shifts. We then compare these rate estimates to those estimated among species and to projected rates of future climate change. Results Remarkably, niche shifts in introduced species are roughly a million times faster than niche shifts among species in their native ranges and roughly 10 times faster than rates of projected climate change. Main conclusions Our results demonstrate that dramatic and rapid niche shifts are possible, although these may be limited in species’ native ranges by biotic interactions and other factors.

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Weather and Climate Extremes, Volume 25〈/p〉 〈p〉Author(s): Jeremy Diaz, Maxwell B. Joseph〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Tornadoes are the most violent of all atmospheric storms. In a typical year, the United States experiences hundreds of tornadoes with associated damages on the order of one billion dollars. Community preparation and resilience would benefit from accurate predictions of these economic losses, particularly as populations in tornado-prone areas increase in density and extent. Here, we use a zero-inflated modeling approach and artificial neural networks to predict tornado-induced property damage using publicly available data. We developed a neural network that predicts whether a tornado will cause property damage (out-of-sample accuracy = 0.821 and area under the receiver operating characteristic curve, AUROC, = 0.872). Conditional on a tornado causing damage, another neural network predicts the amount of damage (out-of-sample mean squared error = 0.0918 and 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"〉〈mrow〉〈msup〉〈mrow〉〈mi〉R〈/mi〉〈/mrow〉〈mrow〉〈mn〉2〈/mn〉〈/mrow〉〈/msup〉〈/mrow〉〈/math〉  = 0.432). When used together, these two models function as a zero-inflated log-normal regression with hidden layers. From the best-performing models, we provide static and interactive gridded maps of monthly predicted probabilities of damage and property damages for the year 2019. Two primary weaknesses include (1) model fitting requires log-scale data which leads to large natural-scale residuals and (2) beginning tornado coordinates were utilized rather than tornado paths. Ultimately, this is the first known study to directly model tornado-induced property damages, and all data, code, and tools are publicly available. The predictive capacity of this model along with an interactive interface may provide an opportunity for science-informed tornado disaster planning.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Heliyon, Volume 5, Issue 7〈/p〉 〈p〉Author(s): Sarvenaz Abolghassem, Shiva Molaei, Shahrzad Javanshir〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this paper, chitin (Ch) was extracted by an optimized method from cuttlebone of the Persian Gulf cuttlefish (Sepiidae, Cephalopoda). The extracted chitin was characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD) and thermal gravimetric analysis (TGA) which showed that the extracted chitin was in alpha form. The degree of N-acetylation (DA) and degree of substitution (DS) of α-chitin were calculated using titration method and FTIR spectroscopy and found to be 80–82% and 19.57 respectively. The α-Chitin was used as biomolecules for the preparation of nanostructured Ch/ZnO via a hydrothermal method. The obtained nanocomposite was characterized using FT-IR, XRD, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) analysis. The antimicrobial aspect of Ch/ZnO nanocomposite was previously proposed. In this paper, attempt was made to add the catalytic feature to these traits. For this purpose, the nanostructured Ch/ZnO was used as reusable nanocatalyst in the green and efficient synthesis of Benzo[a]pyrano(2,3-c)phenazine derivatives thru a four components microwave aided domino reaction. Eco-friendly, easy work up and separation of the nanostructured catalyst are some of the highlighted features this protocol.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Heliyon, Volume 5, Issue 7〈/p〉 〈p〉Author(s): Zurel S. Costa, Cristiano T. Meneses, Bruno Castro, Fabiane S. Serpa, Elton Franceschi, Gustavo R. Borges, Cláudio Dariva, Giancarlo R. Salazar-Banda〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The formation of scales in the petroleum industry, such as those composed of calcium and barium sulfates, may reduce productivity since these sediments can partially or totally obstruct the pipes. The mitigation of these inorganic precipitates can be accomplished by using scale inhibitors or by non-intrusive physical technologies. Here, we investigated the influence of magnetic field on the incrustations of barium sulfate by analyzing the concentration of barium and sulfate ions, the solution flow rate, the capillary tube geometry, and the magnetic field intensity in a homemade experimental unit supported on the monitoring of the dynamic differential pressure. The results show that the saline concentration and the flow rate of the solutions and the geometry of the capillary tube have a significant influence on the dynamics of barium sulfate incrustation. The presence of the magnetic field tends to prolong the induction time of the barium sulfate precipitation. A semi-empirical model was used to describe the effect of the studied variables on the barium sulfate incrustation behavior. The X-ray diffraction data of the precipitated particles analyzed using the Rietveld method suggest that the use of the magnetic field favor the formation of more crystalline particles and with smaller crystallite size than those formed in the absence of a magnetic field. Optical and scanning electron microscopy measurements also corroborate with these findings. The results from this study suggest that magnetic fields can be of interest in practical crystallization processes of barium sulfate and successfully applied to decrease the speed of barium sulfate incrustation in pipelines.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Hydrology: Regional Studies, Volume 24〈/p〉 〈p〉Author(s): Johnson U. Kitheka〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉 〈h6〉Study region〈/h6〉 〈p〉This study was undertaken in the Athi-Sabaki river basin in Kenya in East Africa.〈/p〉 〈/div〉 〈div〉 〈h6〉Study focus〈/h6〉 〈p〉The study focused on the determination of the influence of streamflow variability on salt fluxes. This involved monitoring of river discharge and river salinity in the period between 2012 and 2018.〈/p〉 〈/div〉 〈div〉 〈h6〉New hydrological insights〈/h6〉 〈p〉: This study demonstrates that Athi-Sabaki river discharges significant quantity of salt to the sea. There are significant seasonal and inter-annual variations in salt fluxes that are due to variations in river discharge and rainfall in the basin. The relationship between streamflow variations and variations of salinity in the river was inverse with highest salinity concentrations and fluxes occurring during low flow conditions. The river salinity and TDS concentrations decreased with an increase in river discharge due to dilution effect and flushing of salt from the river. The highly polluted sub-basins draining through the City of Nairobi exhibited relatively higher salinity and salt fluxes as compared to non-polluted ones draining rural areas. The total salt flux in the basin ranged between 29 × 10〈sup〉3〈/sup〉 and 261 × 10〈sup〉3〈/sup〉 tons year〈sup〉−1〈/sup〉. The relatively high salinity and salt fluxes were attributed to the discharge of wastewaters, seepage of groundwater and irrigation return flows. The study calls for water pollution control, sustainable irrigation and landuse practices in the basin.〈/p〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Geoforum, Volume 105〈/p〉 〈p〉Author(s): Arnab Roy Chowdhury, Kuntala Lahiri-Dutt〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Hirashasan is the term used for governance of diamond mining and trade – with a small bureaucracy and an exclusive set of rules and regulations – by the district administration of Panna in the state of Madhya Pradesh in India. Diamond mining in Panna encompasses diverse extractive practices that range from fully mechanised large-scale mining operations owned by the state, to small-scale and semi-mechanised mining carried out by farmers and landowners in groups, to individuals carrying out seasonal and part-time mining of diamonds in an artisanal manner. Based on an ethnographic study was undertaken from September 2016 to April 2017, we argue that Hirashasan has created an “extractive assemblage” that comprises four genres of mining and production systems: large-scale, small-scale, licensed artisanal and unlicensed artisanal. This assemblage is a product of historical, cultural and geographical contingencies as much as place-specificities, and does not lend itself to a single mode of governance. Mineral resource governance in a particular place, therefore, necessitates understanding and internalising the variegated and pluri-form extractive assemblages, such as that of the diamond economy in Panna.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 5 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Technological Forecasting and Social Change〈/p〉 〈p〉Author(s): Sorin M.S. Krammer, Alfredo Jiménez〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We posit that the investments in political connections made by a firm in an emerging market will impact differently its propensity to introduce radical and incremental innovations. In addition, we argue that this effect will be moderated by alternate non-market firm strategies, such as bribery. Using a dataset of more than 9000 firms in 30 emerging economies from Eastern Europe and Central Asia we find that political connections increase the probability of radical innovation but have no significant impact on incremental innovation. Moreover, larger bribing reduces the positive impact of political connections on radical innovation. Our results confirm the importance of political connections for firm activities, but also caution firms on their heterogeneous impact on various types of innovations, and their detrimental interplay with other non-market strategies.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 5 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Transportation Research Part A: Policy and Practice〈/p〉 〈p〉Author(s): Amit Agarwal, Dominik Ziemke, Kai Nagel〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Bicycle is a sustainable low-carbon transport mode. However, insufficient or unplanned infrastructure leads to decrease in the share of bicycle in many cities of developing nations. In order to increase the bicycle share and to provide safer, faster and more direct routes, a bicycle superhighway is proposed for urban areas. This study identifies the potential of increase in the bicycle share. For maximum utilization of the new infrastructure, an algorithm is presented to identify the optimum number and locations of the connectors between proposed new infrastructure and existing network. Household income levels are incorporated into the decision making process of individual travellers for a better understanding of the modal shift. A real-world case study of Patna, India is chosen to show the application of the proposed superhighway. It is shown that for Patna, the bicycle share can escalate as high as 48% up from 32% by providing this kind of infrastructure. However, together with bicycles, allowing motorbikes on the superhighway limits the bicycle share to 44%. The increase in bicycle share is mainly a result of people switching from motorbike, public transport and walk to the bicycle. Further, to evaluate the benefits of the bicycle superhighway, this study first extends an emission modelling tool to estimate the time-dependent, vehicle-specific emissions under mixed traffic conditions. Allowing only bicyclists on the superhighway improves congested urban areas, reduces emissions, and increases accessibility. However, allowing motorbikes on the superhighway increases emissions significantly in the central part of the urban area and reduces accessibilities by bicycle mode to education facilities which are undesirable. This study elicits that a physically segregated high-quality bicycle superhighway will not only attract current non-cyclist travellers and increase the share of the bicycle mode, but will also reduce negative transport externalities significantly.〈/p〉〈/div〉 〈/div〉

Description: Abstract Hydrogeological field studies rely often on a single conceptual representation of the subsurface. This is problematic since the impact of a poorly chosen conceptual model on predictions might be significantly larger than the one caused by parameter uncertainty. Furthermore, conceptual models often need to incorporate geological concepts and patterns in order to provide meaningful uncertainty quantification and predictions. Consequently, several geologically‐realistic conceptual models should ideally be considered and evaluated in terms of their relative merits. Here, we propose a full Bayesian methodology based on Markov chain Monte Carlo (MCMC) to enable model selection among 2D conceptual models that are sampled using training images and concepts from multiple‐point statistics (MPS). More precisely, power posteriors for the different conceptual subsurface models are sampled using sequential geostatistical resampling and Graph Cuts. To demonstrate the methodology, we compare and rank five alternative conceptual geological models that have been proposed in the literature to describe aquifer heterogeneity at the MAcroDispersion Experiment (MADE) site in Mississippi, USA. We consider a small‐scale tracer test (MADE‐5) for which the spatial distribution of hydraulic conductivity impacts multilevel solute concentration data observed along a 2D transect. The thermodynamic integration and the stepping‐stone sampling methods were used to compute the evidence and associated Bayes factors using the computed power posteriors. We find that both methods are compatible with MPS‐based inversions and provide a consistent ranking of the competing conceptual models considered.

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Geomorphology, Volume 343〈/p〉 〈p〉Author(s): Wenmin Yao, Changdong Li, Qingjun Zuo, Hongbin Zhan, Robert E. Criss〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Variations of reservoir water level and seasonal precipitation have resulted in significant movement and destabilization of landslides in the Three Gorges Reservoir (TGR) region of China since reservoir impoundment in 2003. An example is the Baijiabao landslide, a large, actively creeping landslide located in the steep lower valley of the Xiangxi River, about 55 km upstream of the TGR dam in the Yangtze River. Twelve years of monthly monitoring at four GPS stations and routine, monthly field observations show cumulative GPS displacements as large as 〉1.5 m and widely developed ground cracks. GPS monitoring results show that most movement takes place in rapid steps that coincide with the rainy season and the period of annual reservoir drawdown, with particularly large steps in 2009, 2012 and 2015. This step-like pattern of displacement is also shown by daily data from an automatic monitoring system installed in 2017. The total period of acceleration shown by these daily data was about six weeks long, with rapid movement starting during rapid reservoir drawdown, and terminating when the reservoir began to rise again. In particular, most of the 2018 displacement occurred in only two weeks. Different subzones of the landslide move at different rates and exhibit different features of deformation. The neighborhood rough set theory is used to identify the triggering factors responsible for landslide deformation. The most important triggering factors vary between different sites, data types and the time interval used to define them. The surface deformation and ground crack widening are controlled by the combination of rainfall and variations in the reservoir water levels, whereas the deformation of the sliding zone is most sensitive to the latter. The results show that daily data are needed to capture important, short-term landslide responses. The neighborhood rough set theory for determination of triggering factors is suggested for deformation prediction, stability evaluation, and prevention and control of reservoir landslides in this and other regions.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 International Journal of Applied Earth Observation and Geoinformation, Volume 83〈/p〉 〈p〉Author(s): Sergio Sánchez-Ruiz, Álvaro Moreno-Martínez, Emma Izquierdo-Verdiguier, Marta Chiesi, Fabio Maselli, María Amparo Gilabert〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Growing stock volume (GSV) is one of the most important variables for forest management and is traditionally estimated from ground measurements. These measurements are expensive and therefore sparse and hard to maintain in time on a regular basis. Remote sensing data combined with national forest inventories constitute a helpful tool to estimate and map forest attributes. However, most studies on GSV estimation from remote sensing data focus on small forest areas with a single or only a few species. The current study aims to map GSV in peninsular Spain, a rather large and very heterogeneous area. Around 50 000 wooded land plots from the Third Spanish National Forest Inventory (NFI3) were used as reference data, whereas more than 8 000 Landsat-5 TM and Landsat-7 ETM + scenes covering both the study period (1997–2007) and area were chosen as a compromise between availability and suitable temporal and spatial resolution to estimate GSV. Google Earth Engine (GEE) was used to handle the huge amount of remotely sensed data. A total of 805 predictors were calculated from Landsat spectral reflectances. Guided regularized random forests algorithm (RF) was used to deal with the arising multicolinearity and identify the most important predictors by comparing with NFI3 plot-level GSV data. As a result, to model the relationship between spectral information and GSV, the original 805 predictors were reduced to only 29 (highlighting texture metrics, vegetation indices and band ratios involving short wave infrared reflectance) while maintaining the accuracy level (〈em〉R〈/em〉〈sup〉2〈/sup〉 ≈ 0.4 and RMSE ≈ 60 m〈sup〉3〈/sup〉 ha〈sup〉–1〈/sup〉). A 30-m spatial resolution wall-to-wall GSV map over Peninsular Spain was obtained from a standard RF with the 29 selected predictors through GEE. Its accuracy was evaluated against NFI3 province-level GSV data, resulting in 〈em〉R〈/em〉〈sup〉2〈/sup〉 ≈ 0.91 and RMSE ≈ 15 m〈sup〉3〈/sup〉 ha〈sup〉–1〈/sup〉.〈/p〉〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0303243419301898-ga1.jpg" width="298" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: Abstract Laboratory experiments examined the impact of model vegetation on wave‐driven resuspension. Model canopies were constructed from cylinders with three diameters (d = 0.32, 0.64, and 1.26 cm) and 12 densities (cylinders/m2) up to a solid volume fraction (ϕ) of 10%. The sediment bed consisted of spherical grains with d50 = 85 μm. For each experiment, the wave velocity was gradually adjusted by increasing the amplitude of 2‐s waves in a stepwise fashion. A Nortek Vectrino sampled the velocity at z = 1.3 cm above the bed. The critical wave orbital velocity for resuspension was inferred from records of suspended sediment concentration (measured with optical backscatter) as a function of wave velocity. The critical wave velocity decreased with increasing solid volume fraction. The reduction in critical wave velocity was linked to stem‐generated turbulence, which, for the same wave velocity, increased with increasing solid volume fraction. The measured turbulence was consistent with a wave‐modified version of a stem‐turbulence model. The measurements suggested that a critical value of turbulent kinetic energy was needed to initiate resuspension, and this was used to define the critical wave velocity as a function of solid volume fraction. The model predicted the measured critical wave velocity for stem diameters d = 0.64 to 2 cm. Combining the critical wave velocity with an existing model for wave damping defined the meadow size for which wave damping would be sufficient to suppress wave‐induced sediment suspension within the interior of the meadow.

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 World Development, Volume 123〈/p〉 〈p〉Author(s): Alwin Keil, Archisman Mitra, Amit K. Srivastava, Andrew McDonald〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Sustainable intensification (SI) approaches to agricultural development are urgently needed to meet the growing demand for crop staples while protecting ecosystem services and environmental quality. However, SI initiatives have been criticized for neglecting social welfare outcomes. A recent review found that better-off farmers benefitted disproportionately from SI and highlighted the dearth of studies assessing the equity of outcomes. In this study, we explore the social inclusiveness of zero-tillage (ZT) wheat adoption in Bihar, India. ZT is a proven SI technology for enhancing wheat productivity while boosting profitability and reducing greenhouse gas emissions from agricultural machinery in the densely populated Indo-Gangetic Plains. With an average landholding size of 0.39 ha, most farmers in Bihar depend on custom-hiring services to access the technology. While service provision models should foster inclusive growth by reducing financial barriers to technology adoption, early evidence suggested that smallholders remained at a disadvantage. Building on this previous research, we use a panel dataset from 961 wheat-growing households that spans a six-year period to analyze ZT adoption dynamics over time while accounting for the role of social networks and access to service provision. Using a heckprobit approach to correct for non-exposure bias, we compare determinants of ZT awareness and use in 2012 and 2015. We apply a multinomial logit model to identify determinants of early adoption, recent adoption, non-adoption, and dis-adoption. Furthermore, we explore the quality of ZT services as an additional dimension of socially-inclusive technology access. We find that the strong initial scale bias in ZT use declined substantially as awareness of the technology increased and the service economy expanded. Land fragmentation replaced total landholding size as a significant adoption determinant, which also affected the quality of ZT services received. Hence, farmers with small but contiguous landholdings appear to have gained a significant degree of access over time. We conclude that early-stage assessments of SI may be misleading, and that private sector-based service provision can contribute to socially inclusive development outcomes as markets mature.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 World Development, Volume 123〈/p〉 〈p〉Author(s): Chiara Ravetti, Mare Sarr, Daniel Munene, Tim Swanson〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper analyses the ways in which ethnic identity and labour institutions shape favouritism and discrimination among workers. We conduct a lab experiment in the field with South African coal miners from various ethnic groups and with different trade union membership status. Our analysis suggests that union identity and ethnic identity are two social constructs that operate in a distinct and opposite fashion. Unionization acts as a factor of workers solidarity beyond the confine of union membership. Conversely, ethnicity operates as the linchpin through which discrimination among workers is infused not only between ethnic majority and minorities, but also within the majority group itself. We find that the widespread practice of subcontracting in the mining sector exacerbates ethnic discrimination among workers both between and within ethnic groupings.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 World Development, Volume 123〈/p〉 〈p〉Author(s): Vanesa Jordá, Miguel Niño-Zarazúa〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Despite the growing interest in global inequality, assessing inequality trends is a major challenge because individual data on income or consumption is not often available. Nevertheless, the periodic release of certain summary statistics of the income distribution has become increasingly common. Hence, grouped data in form of income shares have been conventionally used to construct inequality trends based on lower bound approximations of inequality measures. This approach introduces two potential sources of measurement error: first, these estimates are constructed under the assumption of equality of incomes within income shares; second, the highest income earners are not included in the household surveys from which grouped data is obtained. In this paper, we propose to deploy a flexible parametric model, which addresses these two issues in order to obtain a reliable representation of the income distribution and accurate estimates of inequality measures. This methodology is used to estimate the recent evolution of global interpersonal inequality from 1990 to 2015 and to examine the effect of survey under-coverage of top incomes on the level and direction of global inequality. Overall, we find that item non-response at the top of the distribution substantially biases global inequality estimates, but, more importantly, it might also affect the direction of the trends.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary Science Reviews, Volume 218〈/p〉 〈p〉Author(s): Weizhe Chen, Dan Zhu, Philippe Ciais, Chunju Huang, Nicolas Viovy, Masa Kageyama〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Climate and atmospheric CO〈sub〉2〈/sub〉 strongly influence the vegetation distribution and the terrestrial carbon storage. Process-based dynamic global vegetation models (DGVM) are important tools for simulating past vegetation dynamics and carbon cycle; yet the link between spatial gradients of climate and vegetation cover in geological past has received less attention. In this study, we simulate the distribution of vegetation under three CO〈sub〉2〈/sub〉 levels for two climate states, the Last Glacial Maximum (LGM) and Pre-industrial (PI) climate with fire activated or deactivated using the ORCHIDEE-MICT DGVM. Results show that elevated CO〈sub〉2〈/sub〉 and warmer climate promote global total tree cover but the impacts are different between forest biomes. Regional tree cover is highly regulated by mean annual precipitation (MAP) especially in the tropics, and by temperature for the boreal-arctic tree line. Based on quantile nonlinear regressions, we analyze the MAP threshold at which maximum tree cover is reached. This threshold is significantly reduced with elevated CO〈sub〉2〈/sub〉 for tropical and temperate trees. With higher CO〈sub〉2〈/sub〉, increased tree cover leads to reduced fire ignition and burned area, and provides a positive feedback to tree cover, especially in Africa. Besides, in our model, increasing CO〈sub〉2〈/sub〉-induced enhancement of gross primary productivity (GPP) is more prominent for tropical trees than for temperate and boreal trees, and for dry regions than wet regions. This difference explains why CO〈sub〉2〈/sub〉 is the major factor influencing forest cover in the tropics. It also highlights that special attention should be paid to collect paleo-vegetation data across savannas-forest transition in dry regions.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 World Development, Volume 123〈/p〉 〈p〉Author(s): Ben Siegelman, Nora Haenn, Xavier Basurto〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper relates how fishermen in San Evaristo on Mexico’s Baja peninsula employ fabrications to strengthen bonds of trust and navigate the complexities of common pool resource extraction. We argue this trickery complicates notions of social capital in community-based natural resource management, which emphasize communitarianism in the form of trust. Trust, defined as a mutual dependability often rooted in honesty, reliable information, or shared expectations, has long been recognized as essential to common pool resource management. Despite this, research that takes a critical approach to social capital places attention on the activities that foster social networks and their norms by arguing that social capital is a process. A critical approach illuminates San Evaristeño practices of lying and joking across social settings and contextualizes these practices within cultural values of harmony. As San Evaristeños assert somewhat paradoxically, for them “lies build trust.” Importantly, a critical approach to this case study forces consideration of gender, an overlooked topic in social capital research. San Evaristeña women are excluded from the verbal jousting through which men maintain ties supporting their primacy in fishery management. Both men’s joke-telling and San Evaristeños’ aversion to conflict have implications for conservation outcomes. As a result, we use these findings to help explain local resistance to outsiders and external management strategies including land trusts, fishing cooperatives, and marine protected areas.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 5 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary International〈/p〉 〈p〉Author(s): Rodrigo Loyola, Lautaro Núñez, Isabel Cartajena〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉It has often been assumed that a link exists between climate change and human dispersion during the initial peopling of the Atacama Desert. However, there is little understanding of how hunter-gatherers acquired and processed environmental information. We examine paleoenvironmental and archaeological data to propose that the early peopling of the highlands of the south-central Atacama was a gradual process modulated by landscape learning. Evidence suggests that initial occupations at the end of the Pleistocene were limited to intermediate altitude levels, where the ecological structure was more easily legible and productive. This allowed human groups to make use of general, transferrable landscape knowledge, based mainly on the hunting of wild camelids and the gathering of plant resources in azonal formations. However, the arid event of the Early Holocene led to successive episodes of abandonment and relocation to new areas, consolidating complementary land-use between the desert lowlands and the high puna. Two complementary strategies for the acquisition and transmission of information can be identified: (1) scouting as part of logistical hunting parties; and (2) information-pooling rooted in broad, flexible social networks. We conclude that in the face of uncertain conditions, hunter-gatherers invested more effort in learning the landscape and sharing environmental knowledge.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Computers & Geosciences, Volume 132〈/p〉 〈p〉Author(s): Hongxing Zhang, Mingliang Zhang, Yongpeng Ji, Yini Wang, Tianping Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Vegetation exerts a significant damping effect on tsunami wave run-up on coastal beaches, thus effectively mitigating the tsunami hazard. A depth-integrated two-dimensional numerical model (HydroSed2D, Liu et al., 2008; Liu et al., 2010) is developed to investigate tsunami wave run-up and land inundation on coastal beaches covered with 〈em〉Pandanus odoratissimus〈/em〉 (〈em〉P. odoratissimus〈/em〉). The present model is based on a finite volume Roe-type scheme, that solves the non-linear shallow water equations with the capacity of treating the wet or dry boundary at the wave front. The momentum equations in this model are modified by adding a drag force term, thus considering the resistance effects of vegetation on tsunami waves. The accuracy of the numerical scheme and the vegetation drag force are validated by three experimental cases of dam-break flow propagation in a dry channel, solitary wave propagation in a vegetated flume, and tsunami run-up over an uneven bed. Subsequently, a numerical model is applied to simulate tsunami run-up and land inundation on actual-scale vegetated beaches and a series of sensitive analyses are conducted by comparing numerical results. The obtained numerical results suggest that 〈em〉P. odoratissimus〈/em〉 can effectively attenuate tsunami run-up and land inundation distance on coastal beaches, and a higher attenuation rate for tsunami wave can be achieved by increasing both vegetation width and vegetation density. The tsunami wave height is also an important factor that impacts the tsunami wave run-up and land inundation on vegetated beaches.〈/p〉〈/div〉 〈/div〉

Description: Evergreen broadleaf forests (EBFs) illustrated higher temporal stability and resistance of EVI than other biomes. Preserving EBFs is beneficial for global vegetation productivity stability and climate mitigation. Abstract Global increase in drought occurrences threatens the stability of terrestrial ecosystem functioning. Evergreen broadleaf forests (EBFs) keep leaves throughout the year, and therefore could experience higher drought risks than other biomes. However, the recent temporal variability of global vegetation productivity or land carbon sink is mainly driven by non‐evergreen ecosystems, such as semiarid grasslands, croplands, and boreal forests. Thus, we hypothesize that EBFs have higher stability than other biomes under the increasingly extreme droughts. Here we use long‐term Standardized Precipitation and Evaporation Index (SPEI) data and satellite‐derived Enhanced Vegetation Index (EVI) products to quantify the temporal stability (ratio of mean annual EVI to its SD), resistance (ability to maintain its original levels during droughts), and resilience (rate of EVI recovering to pre‐drought levels) at biome and global scales. We identified significantly increasing trends of annual drought severity (SPEI range: −0.08 to −1.80), area (areal fraction range: 2%–19%), and duration (month range: 7.9–9.1) in the EBF biome over 2000–2014. However, EBFs showed the highest resistance of EVI to droughts, but no significant differences in resilience of EVI to droughts were found among biomes (forests, grasslands, savannas, and shrublands). Global resistance and resilience of EVI to droughts were largely affected by temperature and solar radiation. These findings suggest that EBFs have higher stability than other biomes despite the greater drought exposure. Thus, the conservation of EBFs is critical for stabilizing global vegetation productivity and land carbon sink under more‐intense climate extremes in the future.

Description: Projected changes in coastal metacommunities driven by ocean warming and acidification based on the elements of the metacommunity structure framework of Leibold and Mikkelson (Oikos 97:237, 2002) and Presley, Higgins, and Willig (Oikos 119:908, 2010). Under present‐day conditions (a) metacommunity is structured by habitat environmental filtering. Under future climate conditions (b) metacommunity is randomly structured. Abstract Predictions of the effects of global change on ecological communities are largely based on single habitats. Yet in nature, habitats are interconnected through the exchange of energy and organisms, and the responses of local communities may not extend to emerging community networks (i.e., metacommunities). Using large mesocosms and meiofauna communities as a model system, we investigated the interactive effects of ocean warming and acidification on the structure of marine metacommunities from three shallow‐water habitats: sandy soft‐bottoms, marine vegetation, and rocky reef substrates. Primary producers and detritus—key food sources for meiofauna—increased in biomass under the combined effect of temperature and acidification. The enhanced bottom‐up forcing boosted nematode densities but impoverished the functional and trophic diversity of nematode metacommunities. The combined climate stressors further homogenized meiofauna communities across habitats. Under present‐day conditions metacommunities were structured by habitat type, but under future conditions they showed an unstructured random pattern with fast‐growing generalist species dominating the communities of all habitats. Homogenization was likely driven by local species extinctions, reducing interspecific competition that otherwise could have prevented single species from dominating multiple niches. Our findings reveal that climate change may simplify metacommunity structure and prompt biodiversity loss, which may affect the biological organization and resilience of marine communities.

Description: Explaining interspecific variation in autumn bird migration phenology trends has been challenging. We performed a spatially explicit time window analysis of weather effects on mean autumn passage of four trans‐Saharan and six intra‐European passerines at the island of Heligoland (Germany) over a 55‐year period (1960–2014). Weather variables at the breeding and stopover grounds explained up to 80% of the species‐specific interannual variability in autumn passage. Overall, wind conditions were most important, but the climatic contributions to the temporal trend in autumn migration phenology consisted of a potpourri of wind, precipitation and temperature effects. Abstract Climate change has caused a clear and univocal trend towards advancement in spring phenology. Changes in autumn phenology are much more diverse, with advancement, delays, and ‘no change' all occurring frequently. For migratory birds, patterns in autumn migration phenology trends have been identified based on ecological and life‐history traits. Explaining interspecific variation has nevertheless been challenging, and the underlying mechanisms have remained elusive. Radar studies on non‐species‐specific autumn migration intensity have repeatedly suggested that there are strong links with weather. In long‐term species‐specific studies, the variance in autumn migration phenology explained by weather has, nevertheless, been rather low, or a relationship was even lacking entirely. We performed a spatially explicit time window analysis of weather effects on mean autumn passage of four trans‐Saharan and six intra‐European passerines to gain insights into this apparent contradiction. We analysed data from standardized daily captures at the Heligoland island constant‐effort site (Germany), in combination with gridded daily temperature, precipitation and wind data over a 55‐year period (1960–2014), across northern Europe. Weather variables at the breeding and stopover grounds explained up to 80% of the species‐specific interannual variability in autumn passage. Overall, wind conditions were most important. For intra‐European migrants, wind was even twice as important as either temperature or precipitation, and the pattern also held in terms of relative contributions of each climate variable to the temporal trends in autumn phenology. For the trans‐Saharan migrants, however, the pattern of relative trend contributions was completely reversed. Temperature and precipitation had strong trend contributions, while wind conditions had only a minor impact because they did not show any strong temporal trends. As such, understanding species‐specific effects of climate on autumn phenology not only provides unique insights into each species' ecology but also how these effects shape the observed interspecific heterogeneity in autumn phenological trends.

Description: 〈p〉Publication date: 15 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Geomorphology, Volume 343〈/p〉 〈p〉Author(s): Nieves G. Valiente, Robert Jak McCarroll, Gerd Masselink, Tim Scott, Mark Wiggins〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Predicting the future behavior of beach and nearshore systems requires an accurate delineation and understanding of coastal cell boundaries, sediment transport pathways, and sediment sources and sinks. Unfortunately, there is a paucity of field datasets on beach and nearshore morphological change that extend fully from the top of the dunes to beyond the depth of closure to enable quantification of the sediment budget. Here, for the first time, we employ a total sediment budget approach, examining a sandy and embayed beach located in the north coast of SW England, to investigate inter- and multi-annual embayment scale sediment dynamics over a 10-year period that includes extreme storm erosion and post-storm recovery. We demonstrate that, despite the deeply embayed nature of the beach, the shoreline orientation roughly parallel to the dominant wave direction and the overwhelmingly cross-shore forcing of the inter-tidal beach volume, the system is neither closed, nor balanced. The very significant net changes in the recorded sediment volume from dune top to depth of closure (−14.5 m ODN), representing a loss of c. 100 m〈sup〉3〈/sup〉 m〈sup〉−1〈/sup〉 during the extreme storm period and a gain of c. 200 m〈sup〉3〈/sup〉 m〈sup〉−1〈/sup〉 during the recovery period, indicate that significant sediment transport occurs seaward of the base of the terminating headlands and beyond the morphological depth of closure. The results further indicate that the inter-tidal region is partly uncoupled from the sub-tidal region, with the former region dominated by cross-shore sediment fluxes, whereas the subtidal region is also significantly affected by longshore sediment fluxes. A conceptual model is presented that balances the observed volume changes with inferred fluxes, forced by variations in total and alongshore wave power. This study contradicts the general assumption that when sediment exits the inter-tidal, it rests undisturbed in the sub-tidal, waiting for a period of low-moderate energy to bring it onshore. The large sediment volumetric variations across the lower shoreface (depth of 5–20 m), which are of the same order of magnitude as, but uncorrelated with, those occurring in the inter-tidal region, are suggestive of an energetic longshore transport system across this deeper region. It is possible that this transport system extends along the whole north coast of SW England and this finding may lead to a shift in understanding of sediment budgets along exposed and macrotidal embayments globally.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0169555X19302739-ga1.jpg" width="439" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Heliyon, Volume 5, Issue 7〈/p〉 〈p〉Author(s): Vanessa Cristina Estevam Bittencourt, Ana Maria dos Santos Moreira, Jeferson Gomes da Silva, Antônio Frederico de Freitas Gomides, Cibele Velloso-Rodrigues, Regina Gendzzelevski Kelmann, Leonardo Meneghin Mendonça, Ivana Silva Lula, Ângelo Márcio Leite Denadai〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The aim of this work was to synthesize and characterize the inclusion compounds formed by the complexation of β-cyclodextrin (βCD) with insecticides from the class of benzoylphenylureas (BPUs), named novaluron (NOV) and diflubenzuron (DIF), beyond evaluate their larvicidal activity against 〈em〉Aedes aegypti〈/em〉 larvae. Solid state characterization by FTIR showed changes in the main peaks of BPUs and βCD, suggesting the formation of inclusion compounds in solid phase. DTA and TGA thermal analysis showed changes in temperatures of BPUs decomposition as result of molecular interactions. 〈sup〉1〈/sup〉H NMR experiments allowed to observe the occurrence of interactions in solution through changes in chemical shifts of BPUs aromatic hydrogens. However, the presence of H–H intermolecular correlations in 2D ROESY was found only for the DIF/βCD complex, suggesting different topology for each complex. Such hypothesis was corroborated by thermodynamic analysis using ITC, which showed different profile of titration curves, beyond endothermic and exothermic interactions for NOV/βCD and DIF/βCD complexes, respectively. DLS titrations of BPUs or BPUs/βCD DMSO solutions in aqueous solution demonstrated that the spontaneously formed hydrophobic nanoprecipitates (HNPs) have different profile of sizes depending on the BPU/βCD system, corroborating also with the hypothesis about the existence of different topologies for each complex. Finally, the HNPs of inclusion compounds showed to be more efficient than free BPUs, allowing proposing a new insecticide formulation.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Heliyon, Volume 5, Issue 7〈/p〉 〈p〉Author(s): Maiko Hayashida, Tsuyoshi Miyaoka, Keiko Tsuchie, Tomoko Araki, Muneto Izuhara, Shoko Miura, Misako Kanayama, Koji Ohtsuki, Michiharu Nagahama, Ilhamuddin Abdul Azis, Rostia Arianna Abdullah, Muhammad Alim Jaya, Ryosuke Arauchi, Sadayuki Hashioka, Rei Wake, Toshiko Tsumori, Jun Horiguchi, Arata Oh-Nishi, Masatoshi Inagaki〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉A reduction of GABAergic markers in postmortem tissue is consistently found in schizophrenia. Importantly, these alterations in GABAergic neurons are not global, which means they are more prevalent among distinct subclasses of interneurons, including those that express the calcium binding protein parvalbumin.〈/p〉 〈p〉A decreased expression of parvalbumin in the hippocampus is a consistent observation not only in postmortem human schizophrenia patients, but also in a diverse number of rodent models of the disease.〈/p〉 〈p〉Meanwhile, previously we reported that the congenital hyperbilirubinemia model rats (Gunn rats), which is a mutant of the Wistar strain, showed behavioral abnormalities, for instance, hyperlocomotor activity, deficits of prepulse inhibition, inappropriate social interaction, impaired recognition memory similar with several rodent models of schizophrenia. Several animal studies linked the importance of palvalbumin in relation to abnormal hippocampal activity and schizophrenia-like behavior.〈/p〉 〈p〉Here, we show that parvalbumin positive cell density was significantly lower in the CA1, CA3 and the total hippocampus of Gunn rats (congenital hyperbilirubinemia model rats) compared to Wistar control rats. The correlations between serum UCB levels and loss of PV expression in the hippocampus were also detected. The decreases in the PV-expression in the hippocampus might suggest an association of the behavioral abnormalities as schizophrenia-like behaviors of Gunn rats, compared to the Wistar control rats.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: July–December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 SoftwareX, Volume 10〈/p〉 〈p〉Author(s): R.D. Martin, Q. Cai, T. Garrow, C. Kapahi〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉QExpy is an open source python-3 module that was developed in order to simplify the analysis of data in undergraduate physics laboratories. Through the use of this module, students can focus their time on understanding the science and the data from their experiments, rather than on processing their data. In particular, the module allows users to easily propagate uncertainties from measured quantities using a variety of techniques (derivatives, Monte Carlo), as well as to plot and fit functions to data. The interface is designed to be pedagogical so that students with no prior programming experience can be eased into using python in their introductory physics laboratories.〈/p〉〈/div〉

Description: 〈p〉Publication date: July–December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 SoftwareX, Volume 10〈/p〉 〈p〉Author(s): Simon Behrendt, Thomas Dimpfl, Franziska J. Peter, David J. Zimmermann〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper shows how to quantify and test for the information flow between two time series with Shannon transfer entropy and Rényi transfer entropy using the 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" altimg="si1.svg"〉〈mi〉R〈/mi〉〈/math〉 package 〈em〉RTransferEntropy〈/em〉. We discuss the methodology, the bias correction applied to calculate effective transfer entropy and outline how to conduct statistical inference. Furthermore, we describe the package in detail and demonstrate its functionality by means of several simulated processes and present an application to financial time series.〈/p〉〈/div〉

Description: 〈p〉Publication date: July–December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 SoftwareX, Volume 10〈/p〉 〈p〉Author(s): Jacob L. Moore, Nathaniel R. Morgan, Mark F. Horstemeyer〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We discuss the creation and implementation of a generalized library, named ELEMENTS, of mathematical functions for supporting a very broad range of element types including: linear, quadratic, and cubic serendipity elements in 2D and 3D; high-order spectral elements; and a linear 4D element. The ELEMENTS library can be used for research and development of both continuous and discontinuous finite element methods for solving a diverse range of partial differential equations. The library has functions for calculating quantities that are commonly used in finite element methods such as the gradient of a basis function, the Jacobi matrix, the inverse Jacobi matrix, the determinant of the Jacobi matrix, and a physical position inside the element, to name a few examples. The library also supports both Gauss–Legendre and Gauss–Lobatto quadrature rules up to 8 quadrature points in each coordinate direction. The examples and discussions in this paper will focus on Lagrangian solid mechanics and dynamics, but ELEMENTS can be used for many other applications.〈/p〉〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Advances in Water Resources, Volume 131〈/p〉 〈p〉Author(s): Maria Maza, Javier L. Lara, Iñigo J. Losada〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉With the aim of better understand and parameterize the physical processes involved in flow-mangrove interaction, wave attenuation and drag forces along a 1:6 scale fringe 〈em〉Rhizophora〈/em〉 mangrove forest are studied experimentally. The 26 m long forest is composed by 135 models built reproducing mature 〈em〉Rhizophora〈/em〉 mangrove trees with 24 prop roots. Hydrodynamic conditions are scaled using Froude similarity based on values collected in nature. Regular and random waves are tested and three water depths are considered to account for the influence of variable mangroves frontal area along the vertical. Wave decay analysis highlights the importance of considering the effect of flume bottom and walls friction. Neglecting this additional damping can result in a high overestimation of the mangrove dissipation capacity. It is proven that water depth, and the associated mangroves frontal area, and wave height are the dominant variables driving wave attenuation for short waves. The slope seaward the forest induces wave shoaling leading to an increase of wave steepness. Accordingly, the exerted forces on the mangroves also increase along the first 3–4 m of the forest. Smaller forces are recorded further into the forest where wave decay formulations fit well to the recorded wave heights. In general, analytical drag forces obtained by using mangrove trees induced damping coefficients compare well to the forces measured within the forest. However, analytical drag forces can lead to overestimations of up to double in some cases. This aspect is very important when experimental results are used to feed numerical or analytical models based on the introduction of a drag force in the momentum equation. These models should be calibrated using, whenever possible, direct force measurements.〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 10 April 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Technological Forecasting and Social Change〈/p〉 〈p〉Author(s): John Rice, Nigel Martin〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Smart Information and Communications Technology (ICT) is envisaged to provide the capabilities to plan, design, construct, operate and manage Australia's key infrastructure. With over 75% of Australia's population living in cities and accessing public and private goods and services, ICT is positioned as a strategic resource for smart infrastructure developments. In this study, international and domestic stakeholder inputs on the future role of smart ICT in advancing Australia's infrastructure development and operations were crowdsourced for analysis. The study identifies several forms of smart ICT (e.g. building information modelling software) enabled infrastructure that possesses potential to deliver over A$9 billion per annum in domestic economic improvements, with commensurate advancement of communities, regions and urban environments. However, to be effective these smart ICT require enablement through open and interoperable data, sound governance and policy, and government leadership and coordination using dedicated resources. While smart infrastructure development is presently slow and lumbering, the identified smart ICT present as valuable strategic technologies for change and development in domestic communities.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 24 April 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Technological Forecasting and Social Change〈/p〉 〈p〉Author(s): Rahat Iqbal, Faiyaz Doctor, Brian More, Shahid Mahmud, Usman Yousuf〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Big Data has significant impact in developing functional smart cities and supporting modern societies. In this paper, we investigate the importance of Big Data in modern life and economy, and discuss challenges arising from Big Data utilization. Different computational intelligence techniques have been considered as tools for Big Data analytics. We also explore the powerful combination of Big Data and Computational Intelligence (CI) and identify a number of areas, where novel applications in real world smart city problems can be developed by utilizing these powerful tools and techniques. We present a case study for intelligent transportation in the context of a smart city, and a novel data modelling methodology based on a biologically inspired universal generative modelling approach called Hierarchical Spatial-Temporal State Machine (HSTSM). We further discuss various implications of policy, protection, valuation and commercialization related to Big Data, its applications and deployment.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 12 April 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Technological Forecasting and Social Change〈/p〉 〈p〉Author(s): F.W. Geels, A. McMeekin, B. Pfluger〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Social acceptance and political feasibility are important issues in low-carbon transitions. Since computer models struggle to address these issues, the paper advances socio-technical scenarios as a novel methodological tool. Contributing to recent dialogue approaches, we develop an eight-step methodological procedure that produces socio-technical scenarios through various interactions between the multi-level perspective and computer models. As a specific contribution, we propose ‘transition bottlenecks’ as a methodological aid to mediate dialogue between qualitative MLP-based analysis of 〈em〉contemporary〈/em〉 dynamics and quantitative, model-generated 〈em〉future〈/em〉 pathways. The transition bottlenecks also guide the articulation of socio-technical storylines that suggest how the social acceptance and political feasibility of particular low-carbon innovations can be improved through social interactions and endogenous changes in discourses, preferences, support coalitions and policies. Drawing on results from the 3-year PATHWAYS project, we demonstrate these contributions for the UK electricity system, developing two low-carbon transition pathways to 2050 commensurate with the 2 °C target, one based on technological substitution (enacted by incumbent actors), and one based on broader system transformation (enacted by new entrants).〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Technological Forecasting and Social Change, Volume 147〈/p〉 〈p〉Author(s): Emrah Karakilic〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The transition from industrial capitalism to cognitive capitalism and the rise of the digital revolution have brought the subject of intellectual property rights to the forefront as a controversial issue. This paper holds that the theoretical apparatus and concepts belonging to the industrial phase of capitalism largely fall short with respect to the repercussions that intellectual property rights regime yields. Embracing the methodological precept that social theory must be moulded in order to address the contours of contemporary social reality, this paper engages in an autonomist Marxist update on the concept of intellectual property rights. It ultimately challenges the “intellectual property rights are a socio-economic need” thesis and speculatively argues that the current system of intellectual property rights, directed politically towards the enclosure of commons, constitutes a structural contradiction by i) forming a basis for a social crisis in terms of the established relations of production, and ii) curtailing a part of the socio-economic opportunities for innovation, profit-making, and growth.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 9 April 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Technological Forecasting and Social Change〈/p〉 〈p〉Author(s): Daniela Maresch, Johannes Gartner〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Disruptive technological change can contribute to a more abundant world. However, potentially disruptive technologies often struggle to significantly influence practice. One prominent example is additive manufacturing (AM). Although AM is often regarded as the next great technological revolution in waiting, it has not yet established itself on a large scale in many fields of application. We investigate the reasons behind those challenges by looking at the various fields in which AM is applied and relating them to the specific challenges AM faces, as well as the opportunities it offers in those fields. Our findings rely on a multi-perspective technology foresight process that is based on a discourse analytic approach and that comprises data tomography covering the biggest German-language online magazine on AM and qualitative interview data collected from a range of AM stakeholders. The findings provide an empirically well-founded evaluation and explanation of the link between the challenges and opportunities offered by AM and the extent to which this disruptive technology is leveraged in specific fields. The findings prompt recommendations on how new potentially disruptive technologies can foster abundance in traditional, well established market economies based on the example of the well-developed but traditional market economy of Austria.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 24 April 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 Technological Forecasting and Social Change〈/p〉 〈p〉Author(s): Måns Nilsson, Adis Dzebo, Georgia Savvidou, Katarina Axelsson〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Quantitative models of transitions, such as energy systems models and integrated assessment models, do not usually represent social processes, institutions and politics. Their view of societal transitions, along with the governance required to drive them, is therefore limited. Socio-technical systems approaches, in contrast, represent the social side but lack a quantitative view of the future system. This paper addresses this by bridging an energy systems model with socio-technical systems analysis and a local action study, analysing the future transition of the residential heating system in Sweden. The paper focuses on demand-side shifts that would drive a transition to a highly efficient, low-carbon heating system until 2050. A conceptual framework for bridging three approaches is introduced and applied. For example, niche-innovations identified in the socio-technical study are implemented as scenario options in the model. Landscape signals are external drivers of the scenario, and the regime study identifies barriers and governance requirements. The local action study provides insights into community attitudes affecting niches and regime change. Our results indicate that the linking of approaches is meaningful, in that it provides an enriched understanding of future systems change in many dimensions. Further research is required using a variety of models on a variety of domains or sectors to draw more generalizable lessons about bridging modelling and social science-based approaches for transition studies.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Hydrology: Regional Studies, Volume 24〈/p〉 〈p〉Author(s): Dagnachew Daniel Molla, Tenalem Ayenew Tegaye, Christopher G. Fletcher〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉 〈h6〉Study region〈/h6〉 〈p〉The volcano-tectonic lakes basin of Abaya-Chamo is part of the Main Ethiopian Rift system and exhibits large variations in geomorphology, physiography and climate between the rift floor and the plateau.〈/p〉 〈/div〉 〈div〉 〈h6〉Study focus〈/h6〉 〈p〉Despite the importance of streamflow for water resources management and planning in the basin, many of the rivers there are ungauged. To make quantitative estimates of streamflow for spatially resolved water availability in such a highly heterogeneous environment, therefore, requires numerical modeling. This study is the first to quantify the surface and shallow groundwater resources in Abaya-Chamo, and to validate the physically fully distributed hydrologic model WetSpass under highly data-limited conditions, in a complex two-lake environment.〈/p〉 〈/div〉 〈div〉 〈h6〉New hydrological insights〈/h6〉 〈p〉Simulated total river flow and estimated baseflow were verified at 15 gauging stations, with a good agreement. The WetSpass model is shown to be suitable for such a complex setting with a correlation coefficient of 0.95 and 0.97 for total flow and baseflow respectively at a statistically significant level (p-value 〈 0.05). The simulated annual water budget reveals that 74.6% of the 22.1 billion lit/yr in total precipitation in the basin is lost through evapotranspiration, 15.7% through surface runoff, and only 9.7% recharges the groundwater system. The simulations also revealed the surface runoff and groundwater recharge are the most sensitive to soil textural class, while evapotranspiration depends more strongly on land use.〈/p〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S2214581818302623-ga1.jpg" width="159" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Geoforum, Volume 105〈/p〉 〈p〉Author(s): Eric Nost, Morgan Robertson, Rebecca Lave〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We present results from a Q-method survey on a key question in water governance and reflect on Q-method as an approach that quantitatively distinguishes qualitative subject-positions. The survey was conducted with the Q-TIP platform, which we designed for the study and is now open to all researchers (〈a href="https://qtip.geography.wisc.edu/" target="_blank"〉https://qtip.geography.wisc.edu/〈/a〉). Our study asked how stream restoration should be evaluated in state regulatory programs. Streams are dynamic and multi-scalar geomorphological, chemical, biological, as well as socio-cultural systems and it is not obvious what good restoration means or how it should be assessed. Across the stream restoration community we found four different priorities, each of which differently characterizes the feasibility of assessing outcomes. These four perspectives were that metrics of success should: (a) be rigorous and site-focused; (b) be simple and easy to implement in the field; (c) capture complexity; (d) reflect innovations in watershed planning, ecosystem functions, and stakeholder inclusion. These subject-positions on assessment do not, however, map cleanly onto informant profession or background, and a single informant can hold more than one view. Despite relatively limited uptake in geography, Q offers the promise of a critical quantitative approach to researching subjectivity in a way that is compatible with poststructural understandings of identity. We use our case material to show that methodological rules of thumb limit Q’s potential, but we demonstrate unconventional approaches. Drawing on the process and results of our survey of stream restoration practitioners, we argue that Q-method can help in the task of representing subjectivity while respecting its complexity.〈/p〉〈/div〉 〈/div〉

Description: A climatology of the boundary‐layer wind‐turning angle over land is presented based on radiosonde observations from 800 stations in the Integrated Global Radiosonde Archive (IGRA). The dependence of the wind turning on a suite of parameters is analyzed. Results from previous studies indicating the importance of the planetary boundary layer (PBL) stratification for the angle of wind turning are confirmed here. A clear increase in the wind‐turning angle with wind speed, particularly for stratified conditions, is also evident. According to Rossby number similarity theory, the cross‐isobaric angle for a neutral and barotropic boundary layer decreases with the surface Rossby number, Ro. The IGRA observations indicate that this dependence on Ro might partly be linked to the dependence of the stratification on the wind speed, a dependence that seems to prevail even for the high wind speeds, a criteria that traditionally is used to approximate a neutral PBL. The vertical distribution of the turning of the wind is analyzed using the high resolution Stratospheric Processes And their Role in Climate (SPARC) data. For unstable cases, there is a maximum in the directional wind shear around the PBL top, whereas for the most stable class of cases there is a maximum near the surface. The wind‐turning angles from observations are also compared with values obtained from ERA‐Interim reanalysis fields, also presented over ocean. ERA‐Interim underestimates the magnitude of the wind‐turning angles as well as the range. Furtheremore, the midlatitude cross‐isobaric mass transport is estimated using the IGRA data. This transport is generally underestimated by ERA‐Interim, likely related to the too small wind‐turning angles. This article is protected by copyright. All rights reserved.

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Hydrology, Volume 576〈/p〉 〈p〉Author(s): Valentin Haselbeck, Jannes Kordilla, Florian Krause, Martin Sauter〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Growing inorganic and expansive hydrochemical datasets and large differences in the measured concentrations require methods that are capable of compressing data without the loss of critical information and subsequently displaying it in a condensed and comprehensive way. Here we train an artificial neural network, Kohonen’s self-organizing map (SOM), to model inorganic hydrochemical clusters and associate the salinity source with the distribution of the ionic concentration spatial variation at a former potash mining site. Kohonen’s self-organizing maps are applied to project the data onto a two-dimensional grid and the geometric relationship of the projected vectors is subsequently used to perform a hierarchical cluster analysis. The SOM clustering approach succeeded in assigning the groundwater samples automatically according to their inorganic chemical composition. Five different clusters, three geogenic and two anthropogenic, were identified. The final outcome is displayed and compared with the classification from Piper plotting of the same dataset. In order to see the SOM clustering results in the large scale hydrogeological context, the distribution of the clusters is displayed spatially. This approach is a tool for the hydrogeologist to quickly analyze large datasets and present them in a clear and concise format.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 15 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary Science Reviews, Volume 218〈/p〉 〈p〉Author(s): Taoliang Zhang, Rujian Wang, Leonid Polyak, Wenshen Xiao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Distribution and composition of coarse particles (〉250 μm) were investigated in 13 sediment cores from the Chukchi margin, western Arctic Ocean. Petrographic clast identification is supplemented by XRF core scanning, EDS analysis of coal fragments, and AMS 〈sup〉14〈/sup〉C dating of planktic foraminifera for age control. Coal debris distribution is also investigated in surface sediments of the study region for provenance interpretation. The sediment-core study focuses on the interval between the Last Glacial Maximum and the Holocene for constraining provenance and timing of the deglacial discharge. We find that this interval is characterized by a distinct enrichment in sedimentary rock fragments, including coal. Comparison with longer stratigraphic records indicates that this composition is unique for the time interval since at least Maine Isotope Stage 5. Based on the timing, interpreted provenance, and geographic distribution of the coal enrichment, we conclude that the most likely primary source was the deglacial discharge from the Mackenzie drainage basin of the Laurentide Ice Sheet (LIS). The identified coal-bearing layer, also expressed in the XRF sulfur record, can be thus used as a stratigraphic marker for the LIS discharge to the Arctic Ocean during the last deglaciation.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 World Development, Volume 123〈/p〉 〈p〉Author(s): Sara Geenen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉By zooming in on the concept of ‘local content’, this article speaks to the debate on extractive industries and development. It challenges two fundamental assumptions of the mainstream local content literature: that production linkages will develop if an enabling environment is created, and that local content is beneficial for local people. Based on almost 600 interviews and focus groups in four mining concessions in Ghana and the Democratic Republic of Congo (DRC) it focuses on how local content policies are translated into concrete practices – more particularly around the granting of contracts and employment. In doing so it unravels the 〈em〉political〈/em〉 dimensions of local content policies and their 〈em〉structural embeddedness〈/em〉 in large-scale extractivist projects. It is argued that local content policies are implemented in complex political arenas, where the power holders use them as political instruments to enhance profit accumulation and control rents. Moreover they are embedded in the structural dynamics that permeate large-scale extractivist projects, producing (new) patterns of exclusion.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary Science Reviews, Volume 217〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: Available online 4 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary International〈/p〉 〈p〉Author(s): Anamaria Roman, Tudor-Mihai Ursu, Sorina Fărcaş, Coriolan Horaţiu Opreanu, Vlad-Andrei Lăzărescu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The landscape at the Roman Archaeological Site from Moigrad-Porolissum, Romania, is nowadays mostly forested. But how did it look during the Roman period (106–275 AD)? Also, how can multispectral imagery and laser scanning be combined more effectively to detect the signatures of ancient sub-surface archaeological remains? This study employed WorldView2 satellite and LiDAR (Light Detection And Ranging) data to explore current remotely sensed vegetation and terrain proxies. These helped identify past anthropogenic signatures embedded within the landscape for reconstructing the ancient engineered environment. The spectral vegetation and terrain patterns revealed 227 marks (36256.22 m) relevant for the historical landscape, of which 182 correspond to ancient sub-surface features. In open landscapes, the two techniques had equivalent results, while LiDAR provided better detection rates in shrubland patches and forests. Their successive application is an advantageous strategy for optimizing costs. The satellite imagery is employed first, followed by the density analysis of the results, while the more expensive laser-based data collection can be focused on the problematic or promising areas. The vegetation and terrain marks revealed the intricate and extensive ancient defensive system that extended on over 24.5 km〈sup〉2〈/sup〉. Their strategic functions, requiring visibility between and around them, suggest large-scale deforestation (probably over 1 km around the structures). Thus, in contrast to the present forest dominance, it appears that in the 2nd and 3rd centuries AD, at Porolissum there was an anthropogenic open landscape covering over 2158 ha, with urbanization and intense military activity on 198.76 ha.〈/p〉〈/div〉 〈/div〉

Description: People with quadriplegia can feed themselves and brush their teeth thanks to nerve surgery – and doctors say it’s time to make the surgery more widely available

Description: 〈p〉Publication date: Available online 4 July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Quaternary International〈/p〉 〈p〉Author(s): Weiwei Sun, Enlou Zhang, Rong Chen, Ji Shen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Organic carbon mineralization and storage in the inland water bodies is an important component of global carbon cycling. However, the mechanisms influencing carbon cycling in the inland water bodies remain uncertain. In this study, 〈em〉n〈/em〉-alkane data from a sediment core spanning the last glacial-interglacial cycle from Lake Xingkai in northeast China, were analyzed to determine response of regional carbon cycling to climate change. Prior to MIS 1 the sedimentary 〈em〉n〈/em〉-alkanes were mainly derived from terrigenous higher plants and helophytes in the wetland. By contrast, non-photosynthetic bacteria are probable major alternating source of sedimentary 〈em〉n〈/em〉-alkanes during MIS 1. The 〈em〉n〈/em〉-alkanes in the sediments are mainly influenced by the variations of lake level and deposition of mineral dust. The total organic carbon content (TOC) and TOC-normalized middle- and long-chain 〈em〉n〈/em〉-alkane concentrations increased during glacial times and decreased during interglacial periods, reflecting higher rates of organic matter decomposition under warmer climatic conditions. The temperature dependence of lacustrine organic matter mineralization suggests that the carbon burial potential of lakes in northeast China will decrease in the future as global warming intensifies.〈/p〉〈/div〉 〈/div〉

Description: Early weather stations only covered 20 per cent of the globe, causing them to underestimate how much our greenhouse gas emissions have warmed the climate

Description: A wildlife survey in Finland has found that by felling trees and building dams, beavers increase the diversity and abundance of woodland mammals

Description: 〈p〉Publication date: July 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Transport Geography, Volume 79〈/p〉 〈p〉Author(s): Saad AlQuhtani, Ardeshir Anjomani〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Dependency on the automobile in the United States has been associated with many urban problems. As a result, many American cities have seen a rebound in public transportation systems—many of whom have built modern rail transit systems. This resurgence of rail transit systems has caused apparent shifts in economic, social, and spatial aspects of neighborhoods located in proximity to rail stations.〈/p〉 〈p〉This study investigates the changes in housing value between 2000 and 2014 in 454 block groups within a one-mile buffer around rail stations located in the Dallas-Fort Worth metropolitan area to determine if there is a correlation between proximity to rail stations and median housing value. This study uses two approaches to analyze the data. First, a comparison of changes in housing value within block groups located in the study area during the study period is introduced. Next, an innovative approach is employed to select the best regression model using the data on the block groups located within the study area to understand the relationships between the selected independent variables and the changes in housing value during the study period in relation to the research question.〈/p〉 〈p〉The findings demonstrate that economic development and commercial activity locations have the highest effect on housing value during the study period, and block groups that were closer to rail stations experienced lower changes in housing value compared to block groups located farther away from stations. An interesting finding contrary to some of the literature is that an increase in the percent of the black population does not have negative effects on the change in property values. The findings for Hispanic and other minorities is also the same. These findings are a useful addition to the existing literature and contribute to the field of urban planning to mitigate the effects on housing value surrounding station areas. In addition, planners and policymakers could use the implications from the findings to adopt some policies for furthering the success of rail transit systems in urban areas by sustaining station area development.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: 1 November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Computational Physics, Volume 396〈/p〉 〈p〉Author(s): Luigi Brugnano, Juan I. Montijano, Luis Rández〈/p〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this paper we study arbitrarily high-order energy-conserving methods for simulating the dynamics of a charged particle. They are derived and studied within the framework of 〈em〉Line Integral Methods (LIMs)〈/em〉, previously used for defining 〈em〉Hamiltonian Boundary Value Methods (HBVMs)〈/em〉, a class of energy-conserving Runge-Kutta methods for Hamiltonian problems. A complete analysis of the new methods is provided, which is confirmed by a few numerical tests.〈/p〉〈/div〉

Description: 〈p〉Publication date: June 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Journal of Transport Geography, Volume 78〈/p〉 〈p〉Author(s): Benjamin K. Sovacool, Johannes Kester, Lance Noel, Gerardo Zarazua de Rubens〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Despite a potentially revolutionary shift towards electric mobility in the passenger vehicle market, the academic and policymaking communities remain wedded to a techno-economic paradigm that may not fully appreciate deeper social and geographic elements of a transition to electric vehicles. In this paper, based primarily on bivariate statistical analysis as well as a hierarchical regression analysis of a survey distributed to 〉5000 respondents across Denmark, Finland, Iceland, Norway, and Sweden, we analyze how perceptions and attitudes towards electric vehicles and vehicle-to-grid technologies differ by income, political affiliation, and geography. Although our findings confirm EV ownership and mobility patterns in general are related to income—those with higher incomes both own more EVs and drive more generally—they also confirm that interest in EVs is not so strongly related. Lower income groups seem to ask less from their cars, thus potentially opening up a market for cheaper low-range alternates. Political orientation is correlated to car and EV ownership, with those on the “left” more interested yet those on the “right” more able and willing to buy expensive cars. Moreover, we see variation in preferences across urban and rural subcategories, and our findings strongly suggest that EVs need not be promoted only for city or suburban areas. When controlling for variables, a multilevel regression analysis does not change the overall thrust of these associations.〈/p〉〈/div〉 〈/div〉

Description: We analyzed the effect of forest age on the climate sensitivity of carbon storage, timber growth rate, and species richness using a unique dataset of 18,507 plots in boreal–temperate forests of eastern North America. Old forests exhibited the highest combined performance and strongest association of the investigated indicators both under baseline and changed climatic conditions. Regions east and southeast of the Great Lakes were particularly vulnerable to climate change. Our findings suggest that strategies aimed at enhancing the representation of older forest conditions in the region will help sustain ecosystem services and biodiversity in a changing world. Abstract Climate change threatens the provisioning of forest ecosystem services and biodiversity (ESB). The climate sensitivity of ESB may vary with forest development from young to old‐growth conditions as structure and composition shift over time and space. This study addresses knowledge gaps hindering implementation of adaptive forest management strategies to sustain ESB. We focused on a number of ESB indicators to (a) analyze associations among carbon storage, timber growth rate, and species richness along a forest development gradient; (b) test the sensitivity of these associations to climatic changes; and (c) identify hotspots of climate sensitivity across the boreal–temperate forests of eastern North America. From pre‐existing databases and literature, we compiled a unique dataset of 18,507 forest plots. We used a full Bayesian framework to quantify responses of nine ESB indicators. The Bayesian models were used to assess the sensitivity of these indicators and their associations to projected increases in temperature and precipitation. We found the strongest association among the investigated ESB indicators in old forests (〉170 years). These forests simultaneously support high levels of carbon storage, timber growth, and species richness. Older forests also exhibit low climate sensitivity of associations among ESB indicators as compared to younger forests. While regions with a currently low combined ESB performance benefitted from climate change, regions with a high ESB performance were particularly vulnerable to climate change. In particular, climate sensitivity was highest east and southeast of the Great Lakes, signaling potential priority areas for adaptive management. Our findings suggest that strategies aimed at enhancing the representation of older forest conditions at landscape scales will help sustain ESB in a changing world.

Description: Temperate plants are at risk of being exposed to late spring freezes—called false springs—which are a major factor determining range limits, can impose high ecological and economic damage, and may be increasing with climate change. Currently, many false spring studies simplify the myriad complexities involved in assessing false spring risks and damage. Here, we review major areas that could improve predictions: understanding how species have evolved to avoid or tolerate false springs (e.g., through shortening how long they are at risk), identifying the cues that underlie spring phenology, and studying how local climate impacts false spring risk. Abstract Temperate plants are at risk of being exposed to late spring freezes. These freeze events—often called false springs—are one of the strongest factors determining temperate plants species range limits and can impose high ecological and economic damage. As climate change may alter the prevalence and severity of false springs, our ability to forecast such events has become more critical, and it has led to a growing body of research. Many false spring studies largely simplify the myriad complexities involved in assessing false spring risks and damage. While these studies have helped advance the field and may provide useful estimates at large scales, studies at the individual to community levels must integrate more complexity for accurate predictions of plant damage from late spring freezes. Here, we review current metrics of false spring, and how, when, and where plants are most at risk of freeze damage. We highlight how life stage, functional group, species differences in morphology and phenology, and regional climatic differences contribute to the damage potential of false springs. More studies aimed at understanding relationships among species tolerance and avoidance strategies, climatic regimes, and the environmental cues that underlie spring phenology would improve predictions at all biological levels. An integrated approach to assessing past and future spring freeze damage would provide novel insights into fundamental plant biology and offer more robust predictions as climate change progresses, which are essential for mitigating the adverse ecological and economic effects of false springs.

Description: As ocean warming and El Niño events increase in intensity, coral reefs, the rainforests of the marine realm, are at the forefront of their associated impacts. The frequency, intensity and spatial extent of coral bleaching are projected to increase in tandem, yet many reefs are located in poorly monitored tropical regions. By tuning marine heatwaves (MHWs) to coral bleaching conditions, we created an atlas of MHWs over the data‐poor Red Sea region, revealing hotspots of reef zones susceptible to bleaching. As this methodology may be applied to any environment, it could help optimize management plans under global environmental change. Abstract As the Earth's temperature continues to rise, coral bleaching events become more frequent. Some of the most affected reef ecosystems are located in poorly monitored waters, and thus, the extent of the damage is unknown. We propose the use of marine heatwaves (MHWs) as a new approach for detecting coral reef zones susceptible to bleaching, using the Red Sea as a model system. Red Sea corals are exceptionally heat‐resistant, yet bleaching events have increased in frequency. By applying a strict definition of MHWs on 〉30 year satellite‐derived sea surface temperature observations (1985–2015), we provide an atlas of MHW hotspots over the Red Sea coral reef zones, which includes all MHWs that caused major coral bleaching. We found that: (a) if tuned to a specific set of conditions, MHWs identify all areas where coral bleaching has previously been reported; (b) those conditions extended farther and occurred more often than bleaching was reported; and (c) an emergent pattern of extreme warming events is evident in the northern Red Sea (since 1998), a region until now thought to be a thermal refuge for corals. We argue that bleaching in the Red Sea may be vastly underrepresented. Additionally, although northern Red Sea corals exhibit remarkably high thermal resistance, the rapidly rising incidence of MHWs of high intensity indicates this region may not remain a thermal refuge much longer. As our regionally tuned MHW algorithm was capable of isolating all extreme warming events that have led to documented coral bleaching in the Red Sea, we propose that this approach could be used to reveal bleaching‐prone regions in other data‐limited tropical regions. It may thus prove a highly valuable tool for policymakers to optimize the sustainable management of coastal economic zones.

Description: Global warming is rapidly advancing the timing of spring leaf‐out in temperate deciduous tree species; however, the interactive effects of temperature and daylength underlying this warming response remain unclear. Based on data from six tree species across 2,377 European phenology observation sites, we found that, in addition to and independent of the known effect of chilling, daylength correlates negatively with the heat requirement for leaf‐out in all studied species. These results provide the first large‐scale empirical evidence of a widespread daylength effect on the temperature sensitivity of leaf‐out phenology in temperate deciduous trees. Abstract Global warming has led to substantially earlier spring leaf‐out in temperate‐zone deciduous trees. The interactive effects of temperature and daylength underlying this warming response remain unclear. However, they need to be accurately represented by earth system models to improve projections of the carbon and energy balances of temperate forests and the associated feedbacks to the Earth's climate system. We studied the control of leaf‐out by daylength and temperature using data from six tree species across 2,377 European phenological network (www.pep725.eu), each with at least 30 years of observations. We found that, in addition to and independent of the known effect of chilling, daylength correlates negatively with the heat requirement for leaf‐out in all studied species. In warm springs when leaf‐out is early, days are short and the heat requirement is higher than in an average spring, which mitigates the warming‐induced advancement of leaf‐out and protects the tree against precocious leaf‐out and the associated risks of late frosts. In contrast, longer‐than‐average daylength (in cold springs when leaf‐out is late) reduces the heat requirement for leaf‐out, ensuring that trees do not leaf‐out too late and miss out on large amounts of solar energy. These results provide the first large‐scale empirical evidence of a widespread daylength effect on the temperature sensitivity of leaf‐out phenology in temperate deciduous trees.

Description: We review the causes of variations in observed and modelled historical trends in water‐use efficiency of plants and ecosystems. We emphasize that even though physiological responses to changing environmental drivers should be interpreted differently depending on the observational scale, there are large uncertainties in each data set which are often underestimated. We provide recommendations for improving observation‐based estimates of water‐use efficiency, which will better inform the representation of the exchange of carbon and water in the vegetation–atmosphere continuum in vegetation models. Abstract Plant water‐use efficiency (WUE, the carbon gained through photosynthesis per unit of water lost through transpiration) is a tracer of the plant physiological controls on the exchange of water and carbon dioxide between terrestrial ecosystems and the atmosphere. At the leaf level, rising CO2 concentrations tend to increase carbon uptake (in the absence of other limitations) and to reduce stomatal conductance, both effects leading to an increase in leaf WUE. At the ecosystem level, indirect effects (e.g. increased leaf area index, soil water savings) may amplify or dampen the direct effect of CO2. Thus, the extent to which changes in leaf WUE translate to changes at the ecosystem scale remains unclear. The differences in the magnitude of increase in leaf versus ecosystem WUE as reported by several studies are much larger than would be expected with current understanding of tree physiology and scaling, indicating unresolved issues. Moreover, current vegetation models produce inconsistent and often unrealistic magnitudes and patterns of variability in leaf and ecosystem WUE, calling for a better assessment of the underlying approaches. Here, we review the causes of variations in observed and modelled historical trends in WUE over the continuum of scales from leaf to ecosystem, including methodological issues, with the aim of elucidating the reasons for discrepancies observed within and across spatial scales. We emphasize that even though physiological responses to changing environmental drivers should be interpreted differently depending on the observational scale, there are large uncertainties in each data set which are often underestimated. Assumptions made by the vegetation models about the main processes influencing WUE strongly impact the modelled historical trends. We provide recommendations for improving long‐term observation‐based estimates of WUE that will better inform the representation of WUE in vegetation models.

Description: We used satellite‐derived leaf chlorophyll content (Chlleaf) to infer leaf photosynthetic capacity () that varies temporally and spatially. The new Chlleaf‐based data set was then incorporated into an established terrestrial biosphere model (i.e. BEPS) to estimate global photosynthesis. Our results show that Chlleaf‐based and its seasonally average values (Chlavg‐based ) can both effectively improve the estimates of photosynthesis when validated against observations at 124 sites of different plant functional types across the globe. This study highlights that Chlleaf is a valuable leaf physiological trait to add in future models to better simulate the terrestrial carbon cycle. Abstract The terrestrial biosphere plays a critical role in mitigating climate change by absorbing anthropogenic CO2 emissions through photosynthesis. The rate of photosynthesis is determined jointly by environmental variables and the intrinsic photosynthetic capacity of plants (i.e. maximum carboxylation rate; ). A lack of an effective means to derive spatially and temporally explicit has long hampered efforts towards estimating global photosynthesis accurately. Recent work suggests that leaf chlorophyll content (Chlleaf) is strongly related to , since Chlleaf and are both correlated with photosynthetic nitrogen content. We used medium resolution satellite images to derive spatially and temporally explicit Chlleaf, which we then used to parameterize within a terrestrial biosphere model. Modelled photosynthesis estimates were evaluated against measured photosynthesis at 124 eddy covariance sites. The inclusion of Chlleaf in a terrestrial biosphere model improved the spatial and temporal variability of photosynthesis estimates, reducing biases at eddy covariance sites by 8% on average, with the largest improvements occurring for croplands (21% bias reduction) and deciduous forests (15% bias reduction). At the global scale, the inclusion of Chlleaf reduced terrestrial photosynthesis estimates by 9 PgC/year and improved the correlations with a reconstructed solar‐induced fluorescence product and a gridded photosynthesis product upscaled from tower measurements. We found positive impacts of Chlleaf on modelled photosynthesis for deciduous forests, croplands, grasslands, savannas and wetlands, but mixed impacts for shrublands and evergreen broadleaf forests and negative impacts for evergreen needleleaf forests and mixed forests. Our results highlight the potential of Chlleaf to reduce the uncertainty of global photosynthesis but identify challenges for incorporating Chlleaf in future terrestrial biosphere models.

Description: Early warning metrics from satellites of drought‐induced tree mortality could be incredibly valuable. We test several metrics in an aspen mortality event and find that these metrics can explain both tree physiological stress during the drought and subsequent mortality after the drought. Abstract Climate change‐driven drought stress has triggered numerous large‐scale tree mortality events in recent decades. Advances in mechanistic understanding and prediction are greatly limited by an inability to detect in situ where trees are likely to die in order to take timely measurements and actions. Thus, algorithms of early warning and detection of drought‐induced tree stress and mortality could have major scientific and societal benefits. Here, we leverage two consecutive droughts in the southwestern United States to develop and test a set of early warning metrics. Using Landsat satellite data, we constructed early warning metrics from the first drought event. We then tested these metrics' ability to predict spatial patterns in tree physiological stress and mortality from the second drought. To test the broader applicability of these metrics, we also examined a separate drought in the Amazon rainforest. The early warning metrics successfully explained subsequent tree mortality in the second drought in the southwestern US, as well as mortality in the independent drought in tropical forests. The metrics also strongly correlated with spatial patterns in tree hydraulic stress underlying mortality, which provides a strong link between tree physiological stress and remote sensing during the severe drought and indicates that the loss of hydraulic function during drought likely mediated subsequent mortality. Thus, early warning metrics provide a critical foundation for elucidating the physiological mechanisms underpinning tree mortality in mature forests and guiding management responses to these climate‐induced disturbances.