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Arid areas cover approximately 41% of Earth's land surface and support more than 38% of the global population. As an important part of drylands, oases are the main carriers of human production, socioeconomic activity, and the ecological environment. Oases typically sustain nearly all of an arid region's human population and produce nearly 95% of its gross domestic product. The ongoing intensification of global warming and human activities has resulted in water stress and water-related environmental problems in arid areas, along with land degradation and desertification. The risk of water shortage and natural disasters in these regions has also increased. The solution to mitigate these environmental issues and achieve ecological security and sustainable socioeconomic development is to accelerate the modernization of oasis ecological agriculture. This can be accomplished by coordinating the contradictions between agricultural, industrial, and domestic water use and ecological water use in arid areas, thereby improving the level of management in oases and strengthening their ability to cope with climate change. [ABSTRACT FROM AUTHOR]

Groundwater serves a range of essential functions such as supplying drinking water, facilitating agricultural practices, and supporting industrial processes. This study examines with multiple methods the quality of groundwater in the agricultural region of Dzira, Algeria. By collecting 38 groundwater samples of different wells and boreholes, valuable awareness of the aptness of groundwater for irrigation in this arid landscape was gained. Most wells met Food and Agriculture Organization (FAO) criteria for the total dissolved solids (TDS) and the potential of hydrogen pH, but some areas had higher mineral content and electrical conductivity. Results show significant TDS variations, with 10.81% of wells exceeding limits and acceptable pH levels. Elevated EC values in 67.57% of wells show high salinity, affecting soil and plant growth. Major ions such as Mg2+ and SO4− exceeded FAO standards in 43.24% and 64.86% of wells, respectively, highlighting substantial mineral content in the groundwater. Suitability indices reveal that most wells pose low sodium hazards and are generally suitable for irrigation, though some areas face moderate to high restrictions. The irrigation water quality index (IWQI) ranged from 45.36 to 96.30, averaging 80.77, with 54.04% classified as "low restriction," suitable for sandy soils with good permeability but requiring caution on salt-sensitive soils. Hydrogeochemical analysis using principal component analysis (PCA) and hierarchical cluster analysis (HCA) identifies rapid evaporite dissolution from Triassic saline formations, with a correlation matrix showing associations between TDS and Ca2⁺, Mg2⁺, Na⁺, Cl⁻, and SO₄2⁻. This mineralization is likely from gypsum and halite. Zoning maps based on IWQI and other parameters depicted spatial variations in groundwater quality, guiding effective irrigation management strategies. Overall, the study underscores the importance of comprehensive water quality assessment for sustainable agriculture and emphasizes the need for targeted interventions to mitigate potential challenges associated with soil salinity and sodicity. Therefore, these findings can be useful to decision-makers and stakeholders in order to optimize water use and protect this vital resource. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water scarcity inhibits plant growth, especially in arid regions. Traditional irrigation methods often lack efficiency and sustainability. This study investigates AquaTrap, a biomimetic design, as a potential solution. The study highlights AquaTrap's advantages by analyzing its design and previous research on bioinspired water harvesting. It highlights its ability to increase water efficiency and support sustainable plant growth in dry areas. Biomimicry inspires AquaTrap's design, which mimics natural systems to capture and deliver water to plant roots. To collect condensation while repelling water, the stack uses superhydrophobic materials. Plant roots then receive this accumulated water for growth. Compared to traditional methods, AquaTrap offers many advantages. Its stand-alone design eliminates complex infrastructure and minimizes evaporation. Additionally, delivering water directly to the roots reduces waste and increases water efficiency. This technology holds promise for introducing new vegetation, restoring plant life, and promoting sustainable agriculture in arid regions. Further research is needed to explore the potential of AquaTrap in a variety of field conditions, optimize it for different plants and environments, and evaluate its economic feasibility for widespread use. AquaTrap also has significant potential for sustainable forestry, as it can significantly increase the survival and growth of trees in water-scarce environments. System solution opportunities and modular structure provide crucial support during the most critical adaptation period of afforestation. By reducing water consumption and increasing efficiency, it supports the establishment and maintenance of healthy forests, which are vital for ecosystem resilience and biodiversity. [ABSTRACT FROM AUTHOR]

Groundwater as a scarce freshwater resource requires extensive quality assessment, control and protection through innovative methods and efficient strategies in light of growing human population, pollution, and over–extraction. Groundwater is critical in arid and semi–arid regions of the world such as the Beaufort West area in the Karoo region of South Africa. Thus, this study investigated the key processes affecting groundwater quality using factor analysis and geospatial models to determine the spatial variability of groundwater quality. To achieve this objective, groundwater samples collected from 49 boreholes located in and around the town of Beaufort West and analysed for electrical conductivity (EC), pH, total dissolved solids (TDS), calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+), bicarbonates (HCO3–), chlorides (Cl–), nitrates (NO3–) and sulphates (SO42–) using recommended standard methods. Factor analysis produced three factors explaining 81.4% of groundwater quality variation. Factor 1 (hardness) was characterised by high concentrations of Cl–, SO42–, Ca2+, Mg2+ and Na+; factor 2 (alkalinity) with HCO3– and K+, and factor 3 (anthropogenic) was characterised by high NO3– concentrations. Derived groundwater quality thematic maps using selected hydrochemical variables and factor scores showed the delineation of areas with hardness, alkalinity and anthropogenic influence on groundwater quality. These findings underscore the relevance of factor analysis and geospatial models in assessing groundwater quality at a catchment scale. [ABSTRACT FROM AUTHOR]

During the 2015–2016 growing season, a field experiment was conducted to investigate the impact of different irrigation regimes (low and severe water stress treatments) and nitrogen levels on the biochemical responses of sorghum and maize. Moisture environments were determined based on the maximum allowable depletion of available soil water (ASW), with depletion levels of 55–60% and 85–90% of ASW selected as the low and severe water stress levels, respectively. Nitrogen fertilizer was applied via drip fertigation at three stages (28, 43, and 55 days after sowing) in the form of Urea (N: 45%), at a rate of 37.5 kg ha−1 N for each stage. Under severe water stress, both crops showed a decrease in chlorophyll and carotenoid content, relative water content (RWC), and maximum quantum efficiency of photosystem II (Fv/Fm). Additionally, severe water stress led to an increase in antioxidant enzyme activity, proline, malondialdehyde (MDA), other aldehydes (Alds), and hydrogen peroxide, ultimately resulting in a 42% reduction in crop yield. Light intensity also increased under severe water stress, particularly in the middle and bottom of the plant canopy, indicating a decrease in the available leaf area for receiving light. Nitrogen application effectively reduced the production of oxygen free radicals, mitigated cell membrane damage, decreased the activity of antioxidant enzymes and osmolytes, and increased the activity of photosynthetic pigments, Fv/Fm, and RWC, resulting in an increase in crop yield of up to 18%. Compared to sorghum, maize exhibited lower antioxidant activity, proline content, chlorophyll, carotenoid, RWC, Fv/Fm, stress tolerance index, and higher concentrations of MDA, Alds, and H2O2, indicating its higher sensitivity to water deficit stress. Additionally, even under low water stress treatment, maize failed to produce an acceptable dry matter yield. [ABSTRACT FROM AUTHOR]

Xinjiang has huge reserves of coal resources and has the conditions and advantages to develop and construct large-scale open-pit coal mines. However, due to the climate characteristics of Xinjiang’s arid areas, open-pit mining has a wide range and high degree of impact on the ecological environment and damage. It is of great practical significance to carry out ecological restoration of open-pit mines in arid areas. Due to the loose materials, high porosity and permeability of the waste dump, the ecological restoration of the waste dump in arid areas is a serious challenge. In order to solve the shortage of water resources in the ecological restoration process of open-pit coal mines in the arid areas of western China, improve the ecological restoration effect of open-pit coal mines in the arid areas, based on the dual technical objectives of material strength and permeability, explore and reconstruct the material ratio of the impervious layer of the open-pit mine external dump, carry out relevant research with different material ratio schemes using indoor permeability test and uniaxial compressive strength. The main composition, uniaxial compressive strength and permeability of the materials with different proportions were determined by XRD diffraction test, uniaxial compression test and variable head permeability test, and the material proportioning parameters of the reconstructed aquiclude were studied. The test results show that the compressive strength of the specimen increases by 22% when the curing agent ratio increases by 2%, but the increasing trend starts to decrease when the curing agent ratio exceeds 8%. When the curing agent ratio increases from 8% to 10%, the compressive strength of the specimen increases by only 6%. With the increase of fly ash content, its permeability decreases gradually. Every 2% increase of fly ash content can reduce the permeability of 28%. The following rules are obtained: the influence of the content of curing agent on the compressive strength of the specimen is greater than that of the fly ash content, and the influence of the fly ash content on the permeability is higher. When the fly ash content is fixed, the curing agent content is positively correlated with the uniaxial compressive strength of the specimen. When the ratio of curing agent is fixed, the uniaxial compressive strength of fly ash increases with the increase of the ratio.

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Apple (Malus pumila Mill.) is one of the important economic crops in the arid areas of Xinjiang, China. For a long time, there has been a problem of high consumption but low yield in water and fertilizer management, prevent improvements in apple quality and yield. In this study, 5-year-old 'Royal Gala' apple trees in extremely arid areas of Xinjiang were used as experimental materials to carry out field experiments. considering 5 irrigation levels (W1, 30 mm; W2, 425 mm; W3, 550 mm; W4, 675 mm; W5, 800 mm) and 5 fertilization levels (F1, 280 kg·ha-1; F2, 360 kg·ha-1; F3, 440 kg·ha-1; F4, 520 kg·ha-1; F5, 600 kg·ha-1) under magnetoelectric water irrigation conditions. The results demonstrated that magnetoelectric water combined with the application of 675 mm irrigation amount and 520 kg·ha-1 fertilization amount was themost effective combination. These results occurred by increasing net photosynthetic rate of apple leaves, improved the quality of apples, increased apple yield, and promoted the improvement of water and fertilizer use efficiency. Additionally, the quadratic regression model was used to fit the response process of yield, IWUE and PFP to irrigation amount and fertilization amount, and the accuracy was greater than 0.8, indicating good fitting effects. The synergistic effect of water and fertilizer has a positive effect on optimizing apple water and fertilizer management. Principal component analysis showed that the magnetoelectric treatment combined water and fertilizer mainly affected apple yield, water and fertilizer use efficiency and vitamin C content related to quality. This study provides valuable guidance for improving water and fertilizer productivity, crop yield and quality in extreme arid areas of Xinjiang by using Magnetoelectric water irrigation. [ABSTRACT FROM AUTHOR]

The aim of this study is exploring the development strategies of ecological agriculture in arid areas through the issue of beet irrigation. Based on the quadratic regression rotation method, a water fertilizer coupling model for film-based sugar beet irrigation was established, reflecting the effects of irrigation water volume, nitrogen fertilizer application amount, and potassium fertilizer application amount on sugar beet yield, and considering the interaction of three factors. The experimental results of 20 experimental fields in Ningxia region, China showed that the three factors affecting sugar beet yield from strong to weak were nitrogen fertilizer application amount, irrigation water amount, and potassium fertilizer application amount. Moreover, there was a strong interaction between irrigation water amount and nitrogen fertilizer application amount on sugar beet yield. Furthermore, based on the results irrigation strategies for sugar beets in arid areas can be provided: during the high-water period, the amount of irrigation water should be appropriately increased and the amount of nitrogen fertilizer applied should be reduced; During the dry season, the amount of irrigation water should be appropriately reduced and the amount of nitrogen fertilizer applied should be increased. [ABSTRACT FROM AUTHOR]

The water-energy-food (WEF) nexus is an interdisciplinary approach to address the transdisciplinary issues of developing a specific area with limited resources. We studied the potential of implementing the WEF model in the Rabia region located at Matrouh Governorate in Egypt on the Mediterranean Sea, to introduce sustainable management solutions for the limited resources in this area. The Rabia community lacks any source of water services and is not connected to the electric grid. It depends on existing wells that harvest rainwater for potable and non-potable purposes. The introduced WEF nexus scheme is based on the available resources in Rabia region to produce the required water for drinking, cultivation, and other purposes in addition to maximizing the productivity of water. It also provided renewable energy resources and food security in the area. The proposal also empowers women and provides job opportunities for the community, in addition to reducing carbon emissions to contribute to the efforts fighting climate change. This work will benefit policymakers, investors, and the local community to take tangible actions toward sustainable development in the region and other similar communities in arid coastal regions. The proposed scheme will save about 52 % of the required electricity and 54 % of the carbon emissions, through the use of renewable energy sources. It produces 2,096 t/yr of crops. It supports the achievement of many sustainable development goals and will promote the achievement of Egypt's National Vision 2030.

The components of water balance (WBC) that involve precipitation, evapotranspiration, runoff, irrigation, and groundwater recharge are critical for understanding the hydrological cycle and water management of resources in semi-arid and arid areas. This paper assesses temporal and spatial distributions of surface runoff, actual evapotranspiration, and groundwater recharge upstream of the New Assiut Barrage (NAB) in the Nile Valley, Upper Egypt, using the WetSpass-M model for the period 2012–2020. Moreover, this study evaluates the effect of land cover/land use (LULC) alterations in the study period on the WBC of the NAB. The data provided as input for the WetSpass-M model in the structure of raster maps using the Arc-GIS tool. Monthly meteorological factors (e.g., temperature, rainfall, and wind speed), a digital elevation model (DEM), slope, land cover, irrigation cover, a soil map, and depth to groundwater are included. The long-term temporal and spatial mean monthly irrigation and precipitation (127 mm) is distributed as 49% (62 mm) actual evapotranspiration, 15% (19 mm) groundwater recharge, and 36% (46 mm) surface runoff. The replacement of cropland by built-up areas was recognized as the primary factor responsible for the major decrease in groundwater, an increase in evapotranspiration and an increase in surface runoff between LCLU in 2012 and 2020. The integration of the WetSpass model with GIS has shown its effectiveness as a powerful approach for assessing WBC. Results were more accurate and reliable when hydrological modeling and spatial analysis were combined. The results of this research can help make well-informed decisions about land use planning and sustainable management of water resources in the upstream area of the NAB. [ABSTRACT FROM AUTHOR]

Natural groundwater recharge (GR) assessment depends on several hydrogeological and climatic inputs, where uncertainty is inevitable. Assessing how inputs' uncertainty affects GR estimation is important; however, it remains unclear in arid areas. This study assesses inputs' uncertainty by examining the changes in GR simulations resulting from modifications in climatic, land use, and soil inputs. A physical-based hydrological model was built to estimate GR from 18 different GR scenarios across Qatar. Scenarios S1–S7 were created from different climatic inputs but identical land use and soil maps. Scenarios S8–S14 were created from different land use maps (analyzed from historical Landsat satellite images) but similar climatic and soil inputs. In S15–S18, the soil parameters were changed while the climatic and land use maps were kept the same. The results show that climatic inputs are key factors controlling the GR in arid areas, followed by land use inputs and soil classification. A strong correlation was observed between the GR values and precipitation, while moderate (non-significant) correlations were observed between the GR values and potential evapotranspiration and wind speed. Soil changes affected the GR simulations but inconsiderably compared with climatic and land use inputs. Since GR estimation is fundamental but uncertain in arid areas, the study findings contribute to narrowing the uncertainty in GR estimation. [ABSTRACT FROM AUTHOR]

Reconstructing the Mid-Holocene climate change in arid and semiarid areas can help predict regional moisture availability and resultant lake evolution and vegetation changes due to future warming. Here, we present a sediment core (YLH15A) from Moon Lake in the Tengger Desert, arid and semiarid China. Based on robust accelerator mass spectrometry 14C dating and multiproxy analyses (pollen, grain size, elements, and total organic carbon), we reconstructed regional climate changes since 7.6 cal ka BP. The climate was generally dry from 7.6 to 2.8 cal ka BP, as indicated by the dried-up lake, strong aeolian activities, and no vegetation, except for a short-term wet interval between 5.4 and 4.9 cal ka BP. The generally dry climate shifted after 2.8 cal ka BP, which is suggested by expanded steppe desert/steppe and increased vegetation cover; it was also accompanied by lake development, which was likely related to increased groundwater recharge originating from regional precipitation and temporary floods from adjacent mountain areas. Our results reveal a prolonged dry Mid-Holocene and relatively wet Late Holocene that are basically consistent with climatic records from the central–east Asian arid and hyperarid areas. The prolonged dry climate in the arid and hyperarid areas is likely to be related to high evaporation triggered by high temperatures during the Middle Holocene. [ABSTRACT FROM AUTHOR]

An environmental challenge of significant concern, particularly in arid and semi-arid regions, is soil salinity, which has adverse effects on soil productivity and agricultural fields. Remote sensing technologies have emerged as a highly promising method for monitoring affected areas, playing a crucial role in land management studies. This paper focuses on estimating soil salinity, soil moisture, and vegetation conditions using Landsat 7 and 8-satellite imagery for the years 2000 to 2019 in a region severely affected by salinity-related issues. We calculated several indices in this study, specifically the Soil Salinity Brightness Index (BI), Salinity Index (SI), and Normalized Difference Salinity Index (NDSI). We conducted a field study to measure the pH and Electrical Conductivity (EC) of various soil samples. The results indicated significant increase in soil salinity due to past droughts and subsequent reductions in humidity in the studied area, which led to the loss of vegetation in Iran's central plateau (Dehshir). The highest levels of soil salinity were observed in the northern and southeastern parts of the region. One of the primary causes of salinization was the occurrence of past droughts and the subsequent desiccation of salt lake. According to the laboratory tests conducted on soil samples, it was observed that in certain sample basins, the pH level reached 8.5, indicating alkaline and sodic soil. Furthermore, the most significant decrease in NDVI values was identified in the northeast and southeast regions of Dehshir. These findings collectively indicate the occurrence of land degradation in the studied area. [ABSTRACT FROM AUTHOR]

In the context of climate change and human activities, flood disasters in arid mountainous areas have become increasingly frequent, and seriously threatened the safety of people's lives and property. Rapid and accurate flash flood inundation modelling is an essential foundational research area, which can aid in the reduction of casualties and the minimization of disaster losses; however, this modelling is also very difficult, and models need to be urgently developed to address flash flood forecasting and warnings. The objective of this study is to construct a numerical modelling method for flash floods in drylands. Based on a 2D high-resolution flood numerical model (FloodMap-HydroInundation2D), we hindcasted the dynamic process of flash flooding and show the spatio-temporal characteristics of flash flood inundation for the "8½18" flash flood disaster that occurred in Datong county, Qinghai province. The results showed that the model output effectively agreed with the observed inundation after the event in terms of both spatial extent and temporal process. Extensive flooding mainly occurred between 00:00 and 01:00 on August 18, 2022. Qingshan, Hejiazhuang and Longwo villages were affected most heavily. We further conducted model sensitivity analysis and found that the model was highly sensitive to both roughness and hydraulic conductivity in drylands, and the effect of hydraulic conductivity was more pronounced. Our study confirmed the good performance of our model for the simulation of flash flooding in arid areas and provides a potential method for flash flood assessment and management in arid areas. [ABSTRACT FROM AUTHOR]

An annotated list of myxomycetes of the Inder salt dome region is provided. The list includes 35 species, 18 have been recorded for the first time in the Atyraus Region of the Republic of Kazakhstan. The list also contains data on the locations, habitats, substrates, and dates of the collected samples, indicating the collection numbers of the herbarium of the Komarov Botanical Institute (LE). Most identified species are widespread in different plant communities and types of substrates. Their number decreases progressively in the sequence of vegetation communities from (1) sage-brush white steppe community Artemisia lercheana on light brown soils with participation of Krascheninnikovia ceratoides and Spiraea hypericifolia in depressions (26 species), (2) sage-brush white steppe communities Artemisia lercheana on cretaceous soil with participation of Krascheninnikovia ceratoides and Anabasis aphylla (21 species), (3) sage-brush steppe communities with Artemisia pauciflora, Anabasis salsa, Atriplex cana (14 species). There are 23 species noted in the "tugay" community: Tamarix ramosissima with Artemisia lercheana, Alhagi pseudalhagi and Peganum harmala. The number of species varies significantly on different substrates. The largest species richness (29) is noted in the epiphytic complex, on the woody parts of the semishrubs, as well as on the bark of shrubs. Arcyria minuta, A. pomiformis, Badhamia spinispora, Comatricha pulchella, Didymium inconspicuum, and Physarum didermoides are found only on these types of substrates. A slightly smaller number (26) is noted on different ground plant litter. Interestingly, Badhamia utricularis is only found on this substrate. Sixteen and nine species were identified on wood debris and weathered dung of herbivorous animals, respectively. [ABSTRACT FROM AUTHOR]

Context dependence arises when ecological relationships vary with the conditions under which they are observed. Context dependence of interactions involving parasites is poorly known, even if it is key to understanding host–parasite relationships and food web dynamics. This paper investigates to which extent predation pressure on an avian ectoparasite (Carnus hemapterus) is context‐dependent. Based on a predator‐exclusion experiment, predation pressure on C. hemapterus pupae in the host's nest for 3 years, and its variation between habitat types are quantified. Variation in precipitation and normalized difference vegetation index (NDVI) is also explored as a likely cause of context dependency. We hypothesize that predation pressure should fluctuate with such surrogates of food availability, so that inter‐annual and intra‐annual differences may emerge. The number of nests with significant reduction of pupae varied widely among years ranging from 24% to 75%. However, average pupae reduction in nests where a significant reduction occurred did not vary between years. No differences in predation rates between habitat types were detected. Precipitation and NDVI varied widely between years and NDVI was consistently lower around nests on cliffs than around nests on trees and farmhouses. Parallels were found between variation in predation pressure and precipitation/NDVI at a wide scale (highest predation the driest year, and much lower the 2 rainier ones), but not at the nest scale. This paper shows clear context‐dependent insect predation pressure on an ectoparasite under natural conditions, and that such interaction changes in signs rather than magnitude between years. The causes for these variations require longer‐term studies and/or well‐designed, large‐scale experiments. [ABSTRACT FROM AUTHOR]

• Morphometric and physiological parameters of cowpea genotypes varied during drought. • More tolerant genotypes accumulated proline and reduced photosynthetic pigments less. • Drought tolerant genotypes reduced less the shoot biomass and physiological features. • Drought tolerance appears to be related to osmotic and oxidative stress adjustments. Cowpea (Vigna unguiculata [L.] Walp.) is one of the most important sources of vitamins, protein, and minerals in Africa, Latin America, and Asia, and Brazil is one of the largest producers in the world. This plant is commonly cultivated in arid and semiarid regions due to its moderate drought tolerance. The use of drought tolerant genotypes is one of the options to be considered in the context of climate change and global food security. Morphometric and physiological analysis were performed to compare cowpea genotypes. Principal component analysis (PCA) was used to identify the traits most likely to contribute to drought tolerance. The genotypes with better morphological and photosynthetic results show greater accumulation of proline and less reduction of photosynthetic pigments, indicating osmotic and oxidative stress adjustment. Among the most drought tolerant cluster formed by the genotypes Costelão, Pituba, Aracê, Inhuma and MOB, the genotypes Pituba, Costelão and Aracê showed the least pronounced reductions in morphological and physiological characteristics when exposed to drought. [ABSTRACT FROM AUTHOR]

Vegetation blanket restoration of mine soils provides a diverse environment for soil microbes, but the effects of vegetation blanket cover on soil physicochemical properties, microbial structure, and diversity are not well understood, particularly in arid areas. In this study, high‐throughput sequencing was used to examine the microbial community at Dafeng Mine, the Helan Mountains, Ningxia, China. Soil microbial communities were analyzed with four different materials: 100% straw, 50% straw–50% coconut, and 100% coconut vegetation blanket types, and a bare ground control (CK). The results showed that the contents of soil total nitrogen (TN), available potassium (AP), urease, and catalase were significantly increased in different types of vegetation blankets. High‐throughput sequencing showed that the straw vegetation blanket increased bacterial diversity, while the coconut vegetation blanket increased fungal diversity. The main influencing factors of the dominant bacterial phylum were total nitrogen, catalase, urease, protease, soil water content (WC), soil organic carbon (SOC), and electrical conductivity (EC). The main influencing factor of the dominant fungal phylum was soil water content. These results show that compared with straw vegetation blankets, coconut, and straw–coconut vegetation blanket mulches are more likely to improve soil physicochemical properties, increase the diversity and abundance of soil microorganisms and improve the structural composition of the community, thus improving the soil environment in dryland mining areas. However, further research is needed as to which is the more significant environmental improvement, coconut or straw–coconut vegetation blankets. [ABSTRACT FROM AUTHOR]

Rainwater harvesting (RWH) systems have been developed to compensate for shortage in the water supply worldwide. Such systems are not very common in arid areas, particularly in the Gulf Region, due to the scarcity of rainfall and their reduced efficiency in covering water demand and reducing water consumption rates. In spite of this, RWH systems have the potential to reduce urban flood risks, particularly in densely populated areas. This study aimed to assess the potential use of RWH systems as urban flood mitigation measures in arid areas. Their utility in the retention of stormwater runoff and the reduction of water depth and extent were evaluated. The study was conducted in a residential area in Bahrain that experienced waterlogging after heavy rainfall events. The water demand patterns of housing units were analyzed, and the daily water balance for RWH tanks was evaluated. The effect of the implementation of RWH systems on the flood volume was evaluated with a two-dimensional hydrodynamic model. Flood simulations were conducted in several rainfall scenarios with different probabilities of occurrence. The results showed significant reductions in the flood depth and flood extent, but these effects were highly dependent on the rainfall intensity of the event. RWH systems are effective flood mitigation measures, particularly in urban arid regions short of proper stormwater control infrastructure, and they enhance the resilience of the built environment to urban floods.

Over arid areas, observations of brightness temperatures by passive microwave radiometers are affected by the variation of the emitting depth with wavelengths. When this variation is unaccounted for, it limits the assimilation of passive microwaves over deserts in Numerical Weather Prediction models and it causes large errors in passive microwave retrievals of land surface temperatures. The emitting depths, along with the corresponding emissivities, are estimated from 10 to 89 GHz, using the non‐Sun‐synchronous observations of the Global Precipitation Mission Microwave Imager to reconstruct the monthly diurnal cycle of brightness temperature. The soil temperature profile is modeled using a two‐term Fourier decomposition based on the ERA5 surface temperature. The combination of the observation and the modeled temperature allows for an estimation of the microwave effective emitting depth. The emitting depth is estimated to be up to 25 cm at 36 GHz, resulting in large differences between the surface temperature and the effective emitting temperature. The variation of emitting depth with frequency is parameterized, and a companion data set provides the necessary parameters to calculate the emitting depth for arid areas between 10 and 89 GHz, globally. The benefit of this parameterization is quantified, with an application to the modeling of observations from the Special Sensor Microwave Imager Sounder over arid areas. Plain Language Summary: Discrepancies have been observed between passive microwave radiometer retrievals of Land Surface Temperature (LST) and the Infrared retrievals of LST in arid areas. This difference has been explained by the combination of two phenomena: a deeper emitting depth for microwave radiation and the variation of temperature with depth and time in the soil. This paper describes the step to obtain a map that allows quantification of this phenomenon for all global arid areas. The map is derived from a combination of observations by the Global Precipitation Measurement (GPM) Microwave Imager sensor and modeling of the microwave signal based on reanalysis data. This will enable the scientific community to take this effect into account in all retrievals relying on passive microwave sensors in arid areas. Key Points: Emissivity and soil temperature affect the passive microwave brightness temperaturesThe effective soil temperature depends on the emitting depth, driven by the dielectric propertiesA map of dielectric permittivity is created to help improve retrievals based on passive microwave observations [ABSTRACT FROM AUTHOR]

(1) Background: In arid and semi-arid reservoirs, water surface evaporation is the main method of water dissipation in order to inhibit the evaporation of water and enhance economic efficiency. The evaporation inhibition rate of water-piled PV at different times of the year is derived from the anti-evaporation test of water-piled PV, and a new idea is proposed for water conservation in plains reservoirs in arid areas. (2) Methods: The test was conducted by dividing the area into groups A and B, with and without PV panel shading. In situ observation and numerical calculation were used to measure the atmosphere's temperatures, test group, and PV module. The saturated water vapor pressure difference was then calculated according to Dalton's principle to analyze the economic benefits of water saving. (3) Results: Based on the test results, it was found that the shading of PV panels had a cooling effect on the water body, the PV module, and the atmosphere. Group A showed a 44.2% decrease in the saturation water vapor pressure difference compared to Group B. The maximum evaporation suppression rate of 40.2% was observed in July, while the minimum rate of 12.2% was observed in January. The average evaporation suppression rate for the entire year was 29.2%. By utilizing the annual water savings for agricultural irrigation, it is possible to cover 38 hm2 of land and generate a revenue of 39,000 CNY. (4) Conclusions: The photovoltaic water cover can effectively reduce water evaporation and generate economic benefits. [ABSTRACT FROM AUTHOR]

In order to realize the ecological restoration of transmission line tower foundation slope and enrich the research methods of slope ecological restoration, this paper studies a nutrient matrix configuration technology for transmission line tower foundation slope in arid areas. The Xilingol arid grassland area in Inner Mongolia is selected as the research object, and plants such as Leymus chinensis, Festuca arundinacea and Agropyron pratense are selected as the grass species of the vegetative substrate configuration technology. Different proportions of water retaining agent, compound fertilizer, microbial agents and other substances are added to the soil, which are combined into 10 test groups. The effect of slope ecological restoration is verified by species suitability, physical and chemical properties of matrix and plant growth. The resβults showed that Caragana korshinskii, Artemisia annua, Astragalus adsurgens, Sonchus oleraceus and other plants are the dominant grass species in the plant substrate plants; The physical and chemical indexes of soil's bulk density, organic matter, total nitrogen and so on in group B2 are better than those in other groups. Adopting the vegetative substrate configuration technology with the proportion of group B2 can obtain a good ecological restoration effect of tower foundation slope of transmission line in arid areas. The vegetative substrate configuration technology can solve the long‐standing ecological and environmental protection problems of the tower foundation slope of transmission line in arid areas, and should be actively promoted and applied. Daur lymphatic is also widely used in ecological restoration of transmission line base slope in arid region. The average coverage rate was 14.85%. The average height was 100.5 cm. It could grow at an altitude of more than 1000 m. After the nutrient matrix of the transmission line base slope was configured, the grass planting belt was established under normal maintenance, and the seeds began to germinate 3 days later. After 10 days, the germination rate was 78% and the coverage rate was 65%. [ABSTRACT FROM AUTHOR]

Due to the environmental problems caused by wind erosion, it is necessary to stabilize the dust centers with mulches. The objective of the present study was to determine and compare the optimum vinasse mulches based on mechanical indicators for sensitive soil stabilization to wind erosion. In this research, vinasse (0, 100, 200 g) is combined with bagasse (0, 25, 50 g), ash bagasse (0, 25, 50 g), filtercake (0, 12.5, 25 g), and one-liter water (81 treatments). At first, the treatments were determined in the appropriate range of salinity and acidity (35 treatments) and in the next step, the mechanical indicators have been measured after mulching on laboratory trays (2×30×100 cm). Optimum mulches have been determined based on five indicators by mean comparison (Duncan). The mean comparison showed that treatments 33, 30, 34, 32, and 19 show the mean difference between the groups based on layer thickness, impact resistance, compressive strength, and shear strength properly. It can be concluded that vinasse (100 and 200 g) with 50 g bagasse reduces the crack coefficient greatly, and the application of vinasse, bagasse, and filtercake does not affect the compressive strength and impact resistance.

Recently, some areas are exposed to water scarcity and floods, and rainwater harvesting (RWH) is a practical solution, particularly in arid and semi-arid regions. The Wadi Watier basin located in South Sinai, Egypt was selected to identify the appropriate RWH techniques. Five alternatives were proposed: a dam with a reservoir, a storage pond, an underground tank, wadi bed cultivation, or a Jessor system. The hydrological model was built using the WMS software to determine the runoff volume at the proposed RWH sites. Multiple criteria were identified and classified based on their suitability degree. Then, an analytic hierarchy process (AHP) was used to assign the effective weight of each evaluation criterion. The AHP revealed that the wadi slope and initial cost have the highest evaluation influence of 20%, followed by the wadi width of 15%. The rainfall volume, social acceptance, and cost revenue have moderate influences with weights from 8 to 11%. Finally, the storage ponds and underground tanks recorded the highest-suitability evaluations at the selected RWH sites, at 65.4 and 62.7%, respectively. The dam with a reservoir recorded 49.3%, which is considered medium suitability, while wadi bed cultivation and Jessor systems were classified as low-suitability evaluations with 42.7 and 41.7%, respectively. HIGHLIGHTS Rainwater harvesting is used to mitigate water scarcity and floods.; Five RWH alternatives were identified and compared due to suitability.; An analytical hierarchy process was applied considering the technical, social, and economic aspects.; Storage ponds and underground tanks recorded high suitability by 65.4 and 62.7%, respectively.; Jessor and wadi bed cultivation systems recorded low suitability by 42.7 and 41.7%, respectively.;

Abstract Over arid areas, observations of brightness temperatures by passive microwave radiometers are affected by the variation of the emitting depth with wavelengths. When this variation is unaccounted for, it limits the assimilation of passive microwaves over deserts in Numerical Weather Prediction models and it causes large errors in passive microwave retrievals of land surface temperatures. The emitting depths, along with the corresponding emissivities, are estimated from 10 to 89 GHz, using the non‐Sun‐synchronous observations of the Global Precipitation Mission Microwave Imager to reconstruct the monthly diurnal cycle of brightness temperature. The soil temperature profile is modeled using a two‐term Fourier decomposition based on the ERA5 surface temperature. The combination of the observation and the modeled temperature allows for an estimation of the microwave effective emitting depth. The emitting depth is estimated to be up to 25 cm at 36 GHz, resulting in large differences between the surface temperature and the effective emitting temperature. The variation of emitting depth with frequency is parameterized, and a companion data set provides the necessary parameters to calculate the emitting depth for arid areas between 10 and 89 GHz, globally. The benefit of this parameterization is quantified, with an application to the modeling of observations from the Special Sensor Microwave Imager Sounder over arid areas.

The saline, alkaline environment of arid soils is conducive to the diffusion of the metalloid arsenic (As). Desert plants in this area are of great ecological importance and practical value. However, there are few studies on the mechanism of arsenic action in desert plants. Therefore, in this study, Eremostachys moluccelloides Bunge was treated with different concentrations of As2O5 [As(V)] to analyze the physiological, biochemical, and transcriptomic changes of its roots and leaves and to explore the molecular mechanism of its response to As(Ⅴ) stress. The activities of catalase, superoxidase, peroxidase, and the contents of malondialdehyde and proline in roots and leaves first increased and then decreased under the As(Ⅴ) stress of different concentrations. The content of As was higher in roots than in leaves, and the As content was positively correlated with As(Ⅴ) stress concentration. In the differentially expressed gene analysis, the key enzymes of the oxidative stress response in roots and leaves were significantly enriched in the GO classification. In the KEGG pathway, genes related to the abscisic acid signal transduction pathway were co-enriched and up-regulated in roots and leaves. The related genes in the phenylpropanoid biosynthesis pathway were significantly enriched and down-regulated only in roots. In addition, the transcription factors NAC, HB-HD-ZIP, and NF-Y were up-regulated in roots and leaves. These results suggest that the higher the As(V) stress concentration, the more As is taken up by roots and leaves of E. molucelloides Bunge. In addition to causing greater oxidative damage, this may interfere with the production of secondary metabolites. Moreover, it may improve As(V) tolerance by regulating abscisic acid and transcription factors. The results will deepen our understanding of the molecular mechanism of As(Ⅴ) response in E. moluccelloides Bunge, lay the foundation for developing and applying desert plants, and provide new ideas for the phytoremediation of As pollution in arid areas.

Ecological security is essential for the development of environmental health and human society. However, the driving mechanisms and spatial non-stationarity of ecological risks are still unknown, particularly in arid areas. Thus, this study constructed an ecological risk index (ERI) research framework in arid areas based on land use and socio-economic data from 1980 to 2020 to investigate the spatiotemporal evolution trend, driving mechanisms, and spatial non-stationarity of ecological risk and predict the ecological risk under business-as-usual, economic development, and ecological protection scenarios using a patch-generating land use simulation (PLUS) model. The results show that: (1) cropland and build-up land were expanding, whereas forestland and grassland water bodies were shrinking. Compared with the two development stages from 1980 to 2000 and from 2000 to 2020, cropland increased by 4.73% and 51.52%, respectively, whereas build-up land increased by 12.64% and 106.52%, respectively, indicating rapid development and drastic changes in the past 20 years. (2) With the change in landscape diversity, the regional ecological risks showed an increasing trend, whereas the future ecological risks showed an increasing trend because of the cumulative effect of landscape pattern changes caused by human activities. (3) Moreover, dramatic changes in ecological risk, particularly in areas of intense human activity in build-up land, agricultural land, artificial oases, and mountainous areas. Corresponding to the analysis of driving mechanisms, population, GDP, distance to government, water, and primary roads; have a significant effect on ecological risk, whereas DEM has direct and indirect effect paths. Ultimately, the proposed analysis framework can present the spatiotemporal changes of ecological risks and their influencing mechanisms, which can help develop sustainable development policies.

This article is devoted to the study of electromagnetic scattering characteristics in arid areas, and proposes environmental monitoring and improvement methods. A four-component soil dielectric model was established to study the relationship of soil dielectric constant with soil moisture and frequency. As the Monte Carlo Method combined with Gaussian spectral function was used to simulate the actual dry ground, the Sparse Matrix/Canonical Grid (SMCG) algorithm model based on the surface current equation was established to calculate the electromagnetic scattering coefficient of arid areas. To verify the correctness of the proposed algorithm, the results obtained by SMCG was compared with those calculated by Method of Moments (MOM), which showed great consistency. Many results were obtained by using the algorithm in this paper, based on the measured soil data in the southeastern area of Ejin Banner, Inner Mongolia. It was found that soil moisture content, area roughness and incident electromagnetic wave segment had influence on the scattering echo and showed regular change. The results of this paper are of guiding significance for soil moisture monitoring, desertification control and agricultural planting in arid areas. [ABSTRACT FROM AUTHOR]

Ecological security evaluation and land space governance are effective ways to ensure regional ecological security and realize sustainable development. This study evaluated the ecological security status at the raster scale and conducted research on the restoration and governance of the national territory, with the aim of implementing accurate restoration, reducing ecological restoration costs, and increasing ecological restoration benefits. Taking the typical arid inland river Shule River Basin as an example, this study selected evaluation factors from production, living, and ecological perspectives, obtained the influencing factors of regional ecological security by spatial principal component analysis, and calculated the ecological security index on the grid scale of production, life and ecological space. The macro-scale national parks, ecological protection red line and other realistic constraints are combined with the grid-scale ecological security evaluation results to achieve accurate land space restoration and governance. The results show that the ecological space accounts for 79.23%, and the production space only accounts for 7.47%, which is similar to other inland river basins in arid areas. The study found that per capita GDP and distance to the road have a significant impact on the ecological security of the study area from the perspectives of production and life, while distance to the water, vegetation coverage, and land cover have a significant impact on ecological security from the ecological perspective. Moderate, moderate low and low ecological security zones account for 72.09% of the total area of the basin, indicating that the ecological security guarantee ability of the Shule River Basin is low. The ecological security level of the living space was the lowest, and the ecological security pattern of the basin area as a whole presented a "higher in the north and south and lower in the middle" characteristic. The land restoration and governance of the Shule River Basin area was divided into five types of ecological control, ecological conservation, ecological enhancement, ecological restoration and ecological management, of which the ecological control area accounted for as much as 35.86%, implying that ecological security in the Shule River Basin has attracted sufficient attention from the government. It is considered that the management of production and living space is more difficult, complex and important, and the proportion of space is relatively small, so it is necessary to focus on the comprehensive management project of ecological protection and restoration. However, the ecological endowment conditions of ecological space in the Shule River Basin are relatively poor, and the distribution area is vast, so natural restoration should be given priority, supplemented by artificial restoration. This study provides a reference for regional ecological security evaluation, ecological civilization construction, and national ecological security research and practice. [ABSTRACT FROM AUTHOR]

Background and objectives: Perennial shrubs play a crucial role in shaping the soil quality within their habitats, influencing soil characteristics through leaf fall and root interactions. This study focuses on the impact of three native woody species-Acer monspessulanum, Prunus scoparia, and Daphne mezerum--on soil quality parameters in the ecologically sensitive and fragile Korkhangan rangelands of southern Yazd province. Considering the susceptibility of these rangelands to desertification, understanding the effects of woody plant species on soil quality is vital for successful rangeland rehabilitation and improvement projects. Methodology: The research investigates the qualitative characteristics of soil under the canopy of the three woody species compared to areas outside the canopy (control) in Korkhangan rangelands. Fifteen sites were selected, and soil samples were collected both under the canopy and outside the canopy at a depth of 0-5 cm. Soil physico-chemical parameters were measured in the laboratory, and statistical analyses (one-way ANOVA and Duncan tests) were employed to compare soil characteristics under the canopy and the control. Results: The study revealed variations in soil nitrogen, phosphorus, potassium, calcium, magnesium, organic matter, acidity, and electrical conductivity under different woody species. Acer monspessulanum demonstrated a significant influence on soil characteristics, with higher levels of nitrogen, phosphorus, potassium, calcium, magnesium, and organic matter compared to the control. The acidity of soils under D. mezerum, P. scoparia, and A. monspessulanum was lower than that outside the canopy. Additionally, electrical conductivity showed variations between A. monspessulanum, P. scoparia, D. mezerum, and the control. Conclusion: The research underscores the distinct impact of native woody species on soil properties in the studied rangelands. Acer monspessulanum exhibited a particularly pronounced effect on soil characteristics. Understanding these relationships can inform effective planning for ecosystem improvement and development activities in rangeland areas. [ABSTRACT FROM AUTHOR]

Under the background of climate change, vegetation restoration in arid area ecosystem is faced with great challenges, which has important research value and is also an important research direction of ecology. In this paper, CiteSpace software was used to carry out data mining and econometric analysis on the research progress of vegetation restoration in arid area ecosystem. Besides, the number of papers published under this topic, the trend of change, the main research strength and the development path of the research topic were presented. The study found that (1) the overall volume of papers showed a significant growing tendency on the whole, and generally experienced three growth stages of slow, steady and rapid growth. The research hotspots were different at different stages. At present, the research mainly focuses on clustering topics such as “soil moisture”, “abandoned farmland”, “biological soil skinning” and “layered soil”, and the cross-study of engineering, hydrology, geosciology and other related disciplines is increasing day by day. (2) China, the United States and Spain were the countries with the largest number of publications, and the Chinese Academy of Sciences was the research institution with the largest number of publications. Li Xinrong and others constituted the core group of authors under the research topic. (3) The strategies of vegetation restoration in response to drought stress and the changing rules of the structure and function of different restored ecosystems under the background of climate change may be the research hotspots of vegetation restoration in arid areas in the near future. [ABSTRACT FROM AUTHOR]

Microbially induced carbonate precipitation (MICP) technology is an environmentally friendly technique that can contribute to tailings consolidation and ecosystem restoration. Our study found that local MICP bacteria, Lysinibacillus fusiformis, could remediate copper tailings pollution at different slope positions (K1, K2, and K3) in arid areas. We analyzed the effect of MICP treatment on the slag from macro- to microscopic levels with a dissolution test, soil physical and chemical tests, wind tunnel testing experiments, and scanning electron microscopy (SEM). The results demonstrated that the MICP bacteria, L. fusiformis, effectively remodeled the slag structure, thereby preventing the diffusion of tailing slag caused by wind erosion. This structural remodeling resulted in a significant increase in slag strength (maximum strength: 2707 KPa) and an increased content of CaCO3. Furthermore, it led to a significant reduction in total salinity content (36.4–43.6%), pH (4.1–4.4%), and improvement in nutritional status (total potassium content (16–31.4%) and the available phosphorus content (2.1–2.3 times) of the tailings slag (p < 0.05). There was also a 15% increase in urease and catalase activity in K1, a 7% increase in invertase activity in K3 (p < 0.05), and a significant increase in carbon and nitrogen microbial biomass in K1, K2, and K3 (p < 0.05). [ABSTRACT FROM AUTHOR]

Accurate classifications of land use/land cover (LULC) in arid regions are vital for analyzing changes in climate. We propose an ensemble learning approach for improving LULC classification accuracy in Xinjiang, northwest China. First, multisource geographical datasets were applied, and the study area was divided into Northern Xinjiang, Tianshan, and Southern Xinjiang. Second, five machine learning algorithms—k-nearest neighbor, support vector machine (SVM), random forest (RF), artificial neural network (ANN), and C4.5—were chosen to develop different ensemble learning strategies according to the climatic and topographic characteristics of each subregion. Third, stratified random sampling was used to obtain training samples and optimal parameters for each machine learning algorithm. Lastly, each derived approach was applied across Xinjiang, and subregion performance was evaluated. The results showed that the LULC classification accuracy achieved across Xinjiang via the proposed ensemble learning approach was improved by ≥6.85% compared with individual machine learning algorithms. By specific subregion, the accuracies for Northern Xinjiang, Tianshan, and Southern Xinjiang increased by ≥6.70%, 5.87%, and 6.86%, respectively. Moreover, the ensemble learning strategy combining four machine learning algorithms (i.e., SVM, RF, ANN, and C4.5) was superior across Xinjiang and Tianshan; whereas, the three-algorithm (i.e., SVM, RF, and ANN) strategy worked best for the Northern and Southern Xinjiang. The innovation of this study is to develop a novel ensemble learning approach to divide Xinjiang into different subregions, accurately classify land cover, and generate a new land cover product for simulating climate change in Xinjiang.

The accurate inversion of actual evapotranspiration (ETa) at a regional scale is crucial for understanding water circulation, climate change, and drought monitoring. In this study, we produced a 1 km monthly ETa dataset for Turpan and Hami, two typical arid cities in northwest China, using multi-source remote sensing data, reanalysis information, and the ETMonitor model from 1980 to 2021. We analyzed the spatiotemporal variation of ETa using various statistical approaches and discussed the impact of climate and land use and cover changes (LUCC) on ETa. The results show the following: (1) the estimation results correlate well with ETa products on monthly scales (coefficient of determination (R2) > 0.85, root mean square error (RMSE) < 15 mm/month) with high reliability. (2) The ETa values were spatially distributed similarly to precipitation and LUCC, with the multi-year (1980–2021) average of 66.31 mm and a slightly fluctuating downward trend (−0.19 mm/a). (3) During the 42-year period, 63.16% of the study area exhibited an insignificant decrease in ETa, while 86.85% experienced pronounced fluctuations (coefficient of variation (CV) > 0.20), and 78.83% will show an upward trend in the future. (4) ETa was significantly positively correlated with precipitation (94.17%) and insignificantly positively correlated with temperature (55.81%). The impact of human activities showed an insignificant decreasing trend (85.41%). Additionally, the intensity of ETa varied considerably among land types, with the largest for cropland (424.12 mm/a). The results of the study have implications for promoting the rational allocation of regional water resources and improving water use efficiency in arid zones. [ABSTRACT FROM AUTHOR]

The Djorf Torba dam belongs to the arid zones and is losing its performance due to a combination of natural and anthropogenic constraints. Indeed, the correlations between rainfall stations are contrasted (r − 0.2 to 0.97), reflecting a strong heterogeneity of rainfall in the same basin. The SPI shows that the basin is subject to recurrent and persistent drought years. Drought conditions predominate in terms of frequency, 58% of years (1972/73 to 2017/2018). In contrast, wet periods are limited to 42% of the total series. For the period from 2009/10 to 2017/18, which is very significant for the water stock of the dam, drought frequencies increase to 69%, and wet periods decrease to 31%. This dam is not spared from siltation, which impacts storage capacity; the 1986 bathymetric survey showed a loss of 09.4% of its original capacity. The loss in volume is 1,976,470 m3/year. The second survey in 2004 indicated a loss of 25.64% of its initial capacity. Siltation forecasts indicate that by 2020 the siltation rate will be 33.29%. The water supply volume in 1999/2000 was 8.78 Mm3/year, increasing to 10.38 Mm3/year in 2014/2015 and 18.06 Mm3/year in 2019/2020. This dam is subject to a persistent drought due to insufficient precipitation and runoff compared to expected or normal values. Its storage capacity is constantly decreasing and has been reduced by more than 1/3 of its initial capacity. At the same time, there is increasing use of the stored water. This state of affairs prompts us to reflect on the effectiveness of constructing large dams in arid zones. [ABSTRACT FROM AUTHOR]

The components of water balance (WBC) that involve precipitation, evapotranspiration, runoff, irrigation, and groundwater recharge are critical for understanding the hydrological cycle and water management of resources in semi-arid and arid areas. This paper assesses temporal and spatial distributions of surface runoff, actual evapotranspiration, and groundwater recharge upstream of the New Assiut Barrage (NAB) in the Nile Valley, Upper Egypt, using the WetSpass-M model for the period 2012–2020. Moreover, this study evaluates the effect of land cover/land use (LULC) alterations in the study period on the WBC of the NAB. The data provided as input for the WetSpass-M model in the structure of raster maps using the Arc-GIS tool. Monthly meteorological factors (e.g., temperature, rainfall, and wind speed), a digital elevation model (DEM), slope, land cover, irrigation cover, a soil map, and depth to groundwater are included. The long-term temporal and spatial mean monthly irrigation and precipitation (127 mm) is distributed as 49% (62 mm) actual evapotranspiration, 15% (19 mm) groundwater recharge, and 36% (46 mm) surface runoff. The replacement of cropland by built-up areas was recognized as the primary factor responsible for the major decrease in groundwater, an increase in evapotranspiration and an increase in surface runoff between LCLU in 2012 and 2020. The integration of the WetSpass model with GIS has shown its effectiveness as a powerful approach for assessing WBC. Results were more accurate and reliable when hydrological modeling and spatial analysis were combined. The results of this research can help make well-informed decisions about land use planning and sustainable management of water resources in the upstream area of the NAB.

Natural groundwater recharge (GR) assessment depends on several hydrogeological and climatic inputs, where uncertainty is inevitable. Assessing how inputs’ uncertainty affects GR estimation is important; however, it remains unclear in arid areas. This study assesses inputs’ uncertainty by examining the changes in GR simulations resulting from modifications in climatic, land use, and soil inputs. A physical-based hydrological model was built to estimate GR from 18 different GR scenarios across Qatar. Scenarios S1–S7 were created from different climatic inputs but identical land use and soil maps. Scenarios S8–S14 were created from different land use maps (analyzed from historical Landsat satellite images) but similar climatic and soil inputs. In S15–S18, the soil parameters were changed while the climatic and land use maps were kept the same. The results show that climatic inputs are key factors controlling the GR in arid areas, followed by land use inputs and soil classification. A strong correlation was observed between the GR values and precipitation, while moderate (non-significant) correlations were observed between the GR values and potential evapotranspiration and wind speed. Soil changes affected the GR simulations but inconsiderably compared with climatic and land use inputs. Since GR estimation is fundamental but uncertain in arid areas, the study findings contribute to narrowing the uncertainty in GR estimation.

The purpose of this experiment is the comparison between four different method of irrigation which include: furrow irrigation, drip tape irrigation, sub-surface (t-tape 5 cm under soil) drip irrigation, and 2-hole bottle irrigation. This experiment was carried out in 2 continuous sowing season first was from November to January and the second one was from January to March of 2020-2021. In the first experiment, it is observed no significant difference in any components of radish which may be due to mild weather condition and sufficient rain fall. However, the best treatment for arid areas like Ahvaz, was bottle irrigation treatment with yield of 680.6 kg. ha-1 and water productivity of 0.3 kg.m-3 and the least irrigated water. In this second experiment due to the lack of rainfall and abundance of sunlight the amount of water consumed for treatments increased. In the experiment bottle irrigation yield was 298.24 kg. ha-1 and water productivity was 0.105 kg.m-3. In conclusion bottle irrigation for poor countries with limited water supply, areas where the cost of assembling a drip system is high or in counties or arid areas which suffer from lack of rainfall can be efficient in producing vegetable for household consumption. For better performance this form of irrigation can be automated which increase system’s productivity. Bottle irrigation is low-cost, easy to operated and doesn’t require manpower which makes it the ideal irrigation for poor countries like Africa and arid areas same as Ahvaz.

In the middle and lower reaches of inland river basins of arid regions, human-intensive exploitation directly determines the distribution patterns of plants in arid areas and further determines the patterns of water use and the water cycle in arid regions. However, human activities on vegetation water utilization and the influence of the water cycle process and mechanism are not clear. In this study, seven observation systems were set up to collect samples in the mountainous, oasis and desert areas of the Shiyang River Basin, an arid inland river in central Asia. In order to quantitatively assess the contribution of different potential water sources to plants, stable isotopes of various water bodies in different geomorphic units of the basin were analyzed. The results showed that precipitation and soil water were the main sources of forest trees in mountainous areas, and the farmland vegetation in the middle and lower reaches of the oasis mainly absorbed soil water supplied by irrigation. The desert area forms vegetation in the ecological water transport area, and vegetation mainly absorbs soil water, lake water and groundwater formed by ecological water transport. On the whole, the water use patterns of plants in mountainous areas are not affected by human activities fundamentally, the oasis area is mainly affected by irrigation activities, and the inland river terminal lake area is mainly affected by ecological water transport. Human activities determine the water use patterns in the middle and lower reaches of inland rivers in arid areas. [ABSTRACT FROM AUTHOR]