Projected Spatiotemporal Dynamics of Drought under Global Warming in Central Asia

Drought, one of the most common natural disasters that have the greatest impact on human social life, has been extremely challenging to accurately assess and predict. With global warming, it has become more important to make accurate drought predictions and assessments. In this study, based on climate model data provided by the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP), we used the Palmer Drought Severity Index (PDSI) to analyze and project drought characteristics and their trends under two global warming scenarios—1.5 °C and 2.0 °C—in Central Asia. The results showed a marked decline in the PDSI in Central Asia under the influence of global warming, indicating that the drought situation in Central Asia would further worsen under both warming scenarios. Under the 1.5 °C warming scenario, the PDSI in Central Asia decreased first and then increased, and the change time was around 2080, while the PDSI values showed a continuous decline after 2025 in the 2.0 °C warming scenario. Under the two warming scenarios, the spatial characteristics of dry and wet areas in Central Asia are projected to change significantly in the future. In the 1.5 °C warming scenario, the frequency of drought and the proportion of arid areas in Central Asia were significantly higher than those under the 2.0 °C warming scenario. Using the Thornthwaite (TH) formula to calculate the PDSI produced an overestimation of drought, and the Penman–Monteith (PM) formula is therefore recommended to calculate the index

Boden- und Landressourceninformationssystem (SLISYS-Tarim) für eine nachhaltige Bewirtschaftung von Flussoasen entlang des Tarim-Flusses, China

Im Rahmen des SuMaRiO Projekts wurde ein Boden- und Landressourceninformationssystem (SLISYS-Tarim) für die räumliche Variabilität der Topographie, Lithologie, Böden, Versalzung und Landnutzung im Tarim-Becken entwickelt. Es dient der regionalen Simulation und Abschätzung der Baumwollerträge. SLISYS-Tarim besteht aus einer Datenbank und einem agro-ökologischen Simulationsmodell namens EPIC. Die Datenbank ist nach SOTER Vorschriften aufgebaut und beinhaltet relationale Tabellen, die Informationen über Topographie, Lithologie, Böden und Landnutzung einschließen. Fernerkundungsdaten von Landsat wurden für die digitale Kartierung der Böden, Versalzung, Landnutzung und Bodenbedeckung angewandt. Eine zusätzliche Datenbank für Klimadaten, Landmanagement und Kulturinformationen wurde ebenfalls mit dem System verknüpft. Die Baumwollerträge wurden von NDVI-Karten abgeleitet, die aus Landsat-8 Bildern erstellt sind. Nach der Kalibrierung des Simulationsmodells EPIC wurde eine räumliche Ertragsabschätzung der Baumwolle unter den aktuellen Bedingungen durchgeführt. Nach der Kalibrierung des Simulationsmodells EPIC wurde eine räumliche Ertragsabschätzung der Baumwolle unter den aktuellen Bedingungen durchgeführt. Die simulierten Erträge wurden mit den von NDVI abgeleiteten Baumwollerträgen verglichen. Dies diente der Validierung des EPIC Modells. Darüber hinaus wurden die Baumwollerträge unter verschiedenen Szenarien von Klimabedingungen, Landmanagement, und Bewässerungsqualität und –quantität simuliert, um die Auswirkungen des Klimawandels auf die Baumwollproduktion und die Nachhaltigkeit der landwirtschaftlichen Systeme im Tarim-Becken abzuschätzen. Die Anwendung des EPIC Modells ergab, dass die Bewässerung und die Bodeneigenschaften - vor allem die Bodenversalzung den größten Einfluss auf die (simulierten) Erträge haben

Impact of groundwater depth and soil salinity on riparian plant diversity and distribution in an arid area of China

Riparian plant diversity in arid regions is sensitive to changes in groundwater. Although it is well known that groundwater has a significant influence on plant diversity, there have been few studies on how groundwater and soil salinity impact plant community in desert riparian ecosystems. Therefore, we surveyed 77 quadrats (100m x 100m) to examine the relationship between groundwater depth, groundwater salinity, soil salinity and plant community in the upper reaches of the Tarim River. Data were analyzed with two-way indicator species analysis (TWINSPAN), detrended canonical correspondence analysis (DCCA) and principal component analysis (PCA). The results indicated that Populus euphratica, Tamarix ramosissima, and Phragmites australis were the dominant plants among trees, shrubs and herbs, respectively. Five plant community types were classified. There were significant differences in species diversity, soil moisture, soil salinity, groundwater depth and groundwater salinity across the community types. The composition and distribution of plant community are significantly influenced by groundwater depth, groundwater salinity, soil moisture, distances from the river to the quadrats, soil pH, electrical conductivity, total salt, CO32-, Cl-, SO42-, Ca2+, Mg2+, Na+ and K+. Shallow groundwater depth, low groundwater salinity, and high soil moisture and soil salinity were associated with higher plant diversity

A hydrated deep eutectic electrolyte with finely-tuned solvation chemistry for high-performance zinc-ion batteries

Despite their cost-effectiveness and intrinsic safety, aqueous zinc-ion batteries have faced challenges with poor reversibility originating from various active water-induced side reactions. After systematically scrutinizing the effects of water on the evolution of solvation structures, electrolyte properties, and electrochemical performances through experimental and theoretical approaches, a hydrated deep eutectic electrolyte with a water-deficient solvation structure ([Zn(H2O)2(eg)2(otf)2]) and reduced free water content in the bulk solution is proposed in this work. This electrolyte can dramatically suppress water-induced side reactions and provide high Zn2+ mass transfer kinetics, resulting in highly reversible Zn anodes (∼99.6% Coulombic efficiency over 1000 cycles and stable cycling over 4500 h) and high capacity Zn//NVO full cells (436 mA h g−1). This work will aid the understanding of electrolyte solvation structure–electrolyte property–electrochemical performance relationships of aqueous electrolytes in aqueous zinc-ion batteries

Three-Dimensional Manganese Oxide@Carbon Networks as Free-Standing, High-Loading Cathodes for High-Performance Zinc-Ion Batteries

Zinc-ion batteries (ZIBs), which are inexpensive and environmentally friendly, have a lot of potential for use in grid-scale energy storage systems, but their use is constrained by the availability of suitable cathode materials. MnO2-based cathodes are emerging as a promising contenders, due to the great availability and safety, as well as the device's stable output voltage platform (1.5 V). Improving the slow kinetics of MnO2-based cathodes caused by low electrical conductivity and mass diffusion rate is a challenge for their future use in next-generation rapid charging devices. Herein, the aforementioned challenges are overcome by proposing a sodium-intercalated manganese oxide (NMO) with 3D varying thinness carbon nanotubes (VTCNTs) networks as appropriate free-standing, binder-free cathodes (NMO/VTCNTs) without any heat treatment. A network construction strategy based on CNTs of different diameters is proposed for the first time to provide high specific capacity while achieving high mass loading. The specific capacity of as-prepared cathodes is significantly increased. The resulting free-standing binder-free cathodes achieve excellent capacity (329 mAh g−1 after 120 cycles at 0.2 A g−1 and 225 mAh g−1 after 200 cycles at 1 A g−1) and long-term cycling stability (158 mAh g−1 at 2 A g−1 after 1000 cycles)

Three-Dimensional Manganese Oxide@Carbon Networks as Free-Standing, High-Loading Cathodes for High-Performance Zinc-Ion Batteries

Zinc-ion batteries (ZIBs), which are inexpensive and environmentally friendly, have a lot of potential for use in grid-scale energy storage systems, but their use is constrained by the availability of suitable cathode materials. MnO2-based cathodes are emerging as a promising contenders, due to the great availability and safety, as well as the device's stable output voltage platform (1.5 V). Improving the slow kinetics of MnO2-based cathodes caused by low electrical conductivity and mass diffusion rate is a challenge for their future use in next-generation rapid charging devices. Herein, the aforementioned challenges are overcome by proposing a sodium-intercalated manganese oxide (NMO) with 3D varying thinness carbon nanotubes (VTCNTs) networks as appropriate free-standing, binder-free cathodes (NMO/VTCNTs) without any heat treatment. A network construction strategy based on CNTs of different diameters is proposed for the first time to provide high specific capacity while achieving high mass loading. The specific capacity of as-prepared cathodes is significantly increased. The resulting free-standing binder-free cathodes achieve excellent capacity (329 mAh g−1 after 120 cycles at 0.2 A g−1 and 225 mAh g−1 after 200 cycles at 1 A g−1) and long-term cycling stability (158 mAh g−1 at 2 A g−1 after 1000 cycles)

When It's Heavier: Interfacial and Solvation Chemistry of Isotopes in Aqueous Electrolytes for Zn-ion Batteries

The electrochemical effect of isotope (EEI) of water is introduced in the Zn-ion batteries (ZIBs) electrolyte to deal with the challenge of severe side reactions and massive gas production. Due to the low diffusion and strong coordination of ions in D2O, the possibility of side reactions is decreased, resulting in a broader electrochemically stable potential window, less pH change, and less zinc hydroxide sulfate (ZHS) generation during cycling. Moreover, we demonstrate that D2O eliminates the different ZHS phases generated by the change of bound water during cycling because of the consistently low local ion and molecule concentration, resulting in a stable interface between the electrode and electrolyte. The full cells with D2O-based electrolyte demonstrated more stable cycling performance which displayed ∼100 % reversible efficiencies after 1,000 cycles with a wide voltage window of 0.8–2.0 V and 3,000 cycles with a normal voltage window of 0.8–1.9 V at a current density of 2 A g−1