Water Resources In Arid Areas Research Articles

Sustainable management of water resources in arid areas

Water is an essential resource for human survival, production and socio-economic development, essential for all forms of life, and essential for the maintenance of healthy ecosystems. Due to the continuous change of climate and the continuous growth of population, economy, region and other factors, water resources are becoming more and more scarce. In arid and semi-arid regions, the coupling and interaction between water resources security, energy security, food security and ecological security are becoming more complex, conflicts and contradictions are gradually emerging or intensifying, and uncertainty and risk levels are increasing. Water utilization and management methods are also becoming increasingly serious and complex, which requires new and innovative approaches to conserve and use water wisely. The sustainable management of water resources has always been the focus of research on water resources in the world, and there is much research on water resources management in major forums. This paper uses the method of review to analyze the relevant articles on water resources management, and puts forward more effective methods for sustainable water resources management, and provides suggestions for follow-up research on sustainable water resources management.

Characteristics and Estimation of Dew in the Loess Hilly Region of Northern Shaanxi Province, China

As a non-precipitation water source, dew is important for plant and animal survival and crop production in arid and water-scarce areas. This study assessed the amount of dew in a dry zone in a long-term (2016 to 2022) field observation experiment at the Ansai Experimental Station, a typical loess hilly area in China. Dew primarily occurred in summer and autumn, with a frequency of >50%. The average annual dew amount was 29.20 mm, with an average annual rainfall of 641.8 mm. The average annual dew-to-rain ratio was 4.58%, and the average annual number of dew days was 143.6 d/a. The surface soil moisture content increased by approximately 1.02% with increasing dew amounts. The change in the soil moisture at a 5 cm depth was 0.14% on average and lagged substantially by 1 h. Using the Beysens model, the annual estimated and measured dew amounts in 2022 were 25.27 and 29.84 mm, respectively, and the annual normalized root mean square deviation (NRMSD) was 0.17. Thus, the Beysens model evaluated the dew amount in the study area well at the monthly and annual scales. The quantification of dew resources can provide support for the development, utilization, and management of limited water resources in arid areas, promoting more accurate decision-making for the sustainable development of water resources in the future.

Analysis of sustainable water resource management and driving mechanism in arid region: a case study of Xinjiang, China, from 2005 to 2020.

The long-term dynamic comprehensive evaluation of the water resource carrying capacity (WRCC) and the analysis of its potential driving mechanism in arid areas are contemporary research issues and technical means of mitigating and coordinating the conflict between severe resource shortages and human needs. The purpose of this study was to explore the distribution of the WRCC and the spatiotemporal heterogeneity of drivers in arid areas based on an improved two-dimensional spatiotemporal dynamic evaluation model. The results show that (1) the spatial distribution of the WRCC in Xinjiang, China, is high in the north, low in the south, high in the west, and low in the east. (2) From 2005 to 2020, the centers of gravity of the WRCC in northern and southern Xinjiang moved to the southeast and west, respectively, and the spatial distribution exhibited slight diffusion. (3) The factors influencing the WRCC exhibit more obvious spatial and temporal heterogeneity. The domestic waste disposal rate and ecological water use rate were the main factors influencing the WRCC in the early stage, while the GDP per capita gradually played a dominant role in the later stage. (4) In the next 30 years, the WRCC in Xinjiang will increase. The results provide a theoretical reference for the sustainable development of water resources in arid areas.

Spatio-temporal variability and trend of blue-green water resources in the Kaidu River Basin, an arid region of China

Study regionKaidu River Basin, an arid region of China Study focusWater resources are scarce and unstable. Adverse changes in blue-green water resources can disrupt water balance and availability in arid regions. Therefore, it is crucial to effectively assess and predict future blue-green water resources in arid areas. This study utilizes the Soil and Water Assessment Tool (SWAT), Patch-generating Land Use Simulation (PLUS), and Global Circulation Models (GCMs) to analyze the interactive impacts of climate and land use/cover changes (LUCC) on blue-green water in arid basin from 1990 to 2050. New hydrological insights for the regionThis work identified key factors influencing blue-green water changes, including forests, grasslands, and snowmelt. In the historical scenarios, the Kaidu River basin exhibited significant interannual variations in blue water and precipitation. In the future scenarios, blue water increases (+3.6%), and green water decreases (−1.8%) under SSP245 (medium emissions). Under SSP585 (high emissions), blue water decreases (−2.4%), and green water increases (+1.8%). Under SSP126 (low emissions), both blue water (+8.5%) and green water (+0.73%) show an increasing trend. The change in snowmelt is the main reason for the first peak of blue water in April May. Under historical and future snowmelt conditions, blue water shows a significant upward or downward trend with the amount of snowmelt. The findings provided practical hints for the enhancement of the management and allocation of precious water resources.

Impact of the Construction of Water Conservation Projects on Runoff from the Weigan River

In order to use water resources more efficiently, the construction of water conservation projects in dryland watersheds has changed the natural water cycle processes. This study used the SWAT (Soil and Water Assessment Tool) model coupled with the glacier module to simulate the hydrological processes in the upper reaches of the Weigan River estuary from 1965 to 1991, to restore and quantitatively evaluate the conditions of the estuarine runoff in the no-reservoir scenario, and to analyse the impact of the construction of water conservation projects on the estuarine runoff based on this model. The results show that the SWAT model has good applicability in the study area, with 41.45% and 58.55% of the increase in runoff due to increased precipitation and temperature, respectively, over the 52 years study period. The degree of influence of the construction of water conservation projects on runoff from the mountain in different seasons was spring > autumn > winter > summer, with 83.28% of the spring runoff being influenced by artificial regulation. The construction of water conservation projects has alleviated water shortage problems to a certain extent, and is an effective measure for achieving the efficient allocation of water resources in arid areas.

Numerical simulation of the enhancing effect of micro–nano protrusions on electrostatic fog harvesting

Fog harvesting is one potential approach to provide supplementary water resources in arid areas. Considerable research has been devoted to electrostatic fog harvesting technology, but there are still some problems, such as high voltage, complex structures and expensive cost. Decorating micro–nano protrusions on the electrode is an effective method to lower the operating voltage and improve fog harvesting efficiency, and the enhancement effect of protrusions has already been experimentally demonstrated. However, the enhancement mechanism at the microscopic level is less reported. This manuscript tries to explain why micro–nano protrusions can enhance the discharge and electrostatic fog harvesting, via numerical simulation. Three key processes of corona discharge, fog droplet migration and fog harvesting efficiency are discussed in detail, especially the influence of droplet size, the tip radius of the protrusion, the protrusion–protrusion angle and so on. The numerical simulation results show that the inception voltage of the barbed electrode decreases from 7 kV to 3 kV (a decrease of 57%), and the current increases significantly (e.g. by 68% at 15 kV). At 15 kV, the fog harvesting efficiency of the barbed electrode is higher (29.8%) than that of the smooth wire (25.7%), even with a less-effective collection area. The collection efficiency increases with the droplet size, and there is an optimized ratio (∼1‰) of the protrusion tip radius and wire radius to gain high collection efficiency. These research results are beneficial for understanding the microscopic mechanism of protrusions that enhance electrostatic fog harvesting, and provide guidance for further fog harvesting equipment improvement.

Effects of Human Activities on Evapotranspiration and Its Components in Arid Areas

With the increasing impact of human activities on the environment, evapotranspiration (ET) has changed in arid areas, which further affects the water resources availability in the region. Therefore, understanding the impact of human activities on ET and its components is helpful to the management of water resources in arid areas. This study verified the accuracy of Fisher's model (PT-JPL model) for ET estimation in southern Xinjiang, China by using the evaporation complementarity theory dataset (AET dataset). The ET and the evapotranspiration components (T:E) of six land-use types were estimated in southern Xinjiang from 1982 to 2015, and the impact of human activities on ET was analyzed. In addition, the impact of four environmental factors (temperature (Temp), net radiation (Rn), relative humidity (RH), and NDVI) on ET were evaluated. The results showed that the calculated ET values of the PT-JPL model were close to the ET values of the AET dataset. The correlation coefficient (R2) was more than 0.8, and the NSE was close to 1. In grassland, water area, urban industrial and mining land, forest land, and cultivated land, the ET values were high, and in unused land types, the ET values were the lowest. The T:E values varied greatly in urban industrial and mining land, forest land, and cultivated land, which was due to the intensification of human activities, and the values were close to 1 in summer in recent years. Among the four environmental factors, temperature largely influenced the monthly ET. These findings suggest that human activities have significantly reduced soil evaporation and improved water use efficiency. The impact of human activities on environmental factors has caused changes in ET and its components, and appropriate oasis expansion is more conducive to regional sustainable development.

High-Resolution Inversion Method for the Snow Water Equivalent Based on the GF-3 Satellite and Optimized EQeau Model

High-resolution snow water equivalent studies are important for obtaining a clear picture of the potential of water resources in arid areas, and SAR-based sensors can achieve meter-level snow water equivalent inversion. The advanced C-band SAR satellite Gaofen-3 (GF-3) can now achieve meter-level observations of the same area within one day and has great potential for the inversion of the snow water equivalent. The EQeau model is an empirical method for snow water equivalent inversion using C-band SAR satellites, but the model has major accuracy problems. In this paper, the EQeau model is improved by using classification of underlying surface types and polarization decomposition, and the inversion of the snow water equivalent was also completed using the new data source GF-3 input model. The results found that: (1) the classification of underlying surface types can significantly improve the fit between the snow thermal resistance and the backscattering coefficient ratio; (2) the accuracy of the snow density extracted by the GF-3 satellite using the Singh–Cloude Three-Component Hybrid (S3H) decomposition is better than IDW spatial interpolation, and the overall RMSE can reach 0.005 g/cm3; (3) the accuracy of the optimized EQeau model is significantly improved, and the overall MRE is reduced from 27.4% to 10.3%. Compared with the original model, the optimized model is superior both in terms of verification accuracy and image detail. In the future, with the combination of advanced technologies such as the Internet of Things (IoT), long, gapless, all-weather, and high-resolution snow water equivalent inversion can be achieved, which is conducive to the realization of all-weather monitoring of the regional snow water equivalent.

Joint operation of surface water and groundwater base on parallel-flower pollination algorithm

The joint operation of surface water and groundwater is an effective way to solve the shortage of water resources in arid areas of Northwest China, which is of great significance for efficient utilization of water resources. Taking the Heihe River Basin in Gansu Province as an example, this paper proposes two water supply mechanisms: groundwater based, surface water compensation and surface water based, and groundwater compensation. Taking the groundwater withdrawal and surface water reservoir level as optimization variables, a multi-objective model considering irrigation and ecology and considering hydropower generation is established, and Parallel Flower Pollination Algorithm (P-FPA) is introduced to solve the problem. The results show that the water supply mechanism based on groundwater and surface water compensation can significantly improve the downstream ecological objectives on the basis of meeting the irrigation guarantee rate in the middle reaches; the parallel flower pollination algorithm has significant stability and optimization ability, which is a new method for reservoir optimal operation. The research results not only provide a new idea for the joint operation of surface water and groundwater in arid areas, but also provide important guidance for alleviating the water resources contradiction and improving the utilization efficiency of water resources in Heihe River Basin.

A novel multi-model fusion framework diagnoses the complex variation characteristics of ecological indicators and quantitatively reveals their driving mechanism.

Systematic analysis of the change law and driving mechanism of ecological indicators (GPP, ET, WUE), as well as the study of maximum threshold of water resources benefit changing with ecological benefit, are important prerequisites for realizing the scientific allocation and efficient utilization of water resources in desert riparian forests. However, previous studies have defects in the detailed description of the change characteristics of ecological indicators. How to accurately diagnose the characteristics of a site, mutation year, pattern (linear, exponential, logarithmic, etc.), duration of change, future change trends of ecological indicators in a desert riparian environment, as well as quantitatively revealing their driving mechanisms, are major scientific problems that need to be solved urgently. In this regard, an ensemble function coupling a logistic function and an asymmetric Gaussian function was creatively adopted, a novel framework was created to integrate the time-series trajectory fitting method and the sensitivity analysis method, and the arid and ecologically fragile Tarim River Basin was taken as a typical area. The results showed that with enhanced water resource management in the Tarim River Basin, GPP, ET, and WUE all showed patterns of increasing change and could be expected to continue to rise or to remain at a high-level stable state. The longest continuous period of GPP change was 15 years, showing that ecological restoration is a long-term process. The years of GPP mutation were consistent with the implementation periods of major measures in the Tarim River Basin (1990, 2001, and 2011), indicating the reliability of this framework. More importantly, when GPP increased to 216.44 gCm-2, the maximum WUE threshold of 0.93 gCm-2mm-1 occurred. This threshold can be used as a reference criterion for efficient utilization of ecological water in the basin. Among the ecological indicators studied, GPP was the most sensitive to environmental change, but GPP, with 80.60% of pixel area, showed a weak memory effect（α<0.4). Besides, GPP was the most sensitive to the leaf area index (LAI) and had the strongest correlation with it (p<0.001). Therefore, LAI can be used as the main control factor for judging plant growth. This research can provide important scientific guidance and reference for the analysis of ecological indicator changes and the sustainable utilization of water resources in arid areas.

Study on the Spatial Allocation of Receding Land and Water Reduction under Water Resource Constraints in Arid Zones

The withdrawal of cultivated land policy is not only an important task to promote cultivated land rest and alleviate the contradiction between supply and demand of water resources in arid areas, but also an important way to realize the sustainable development of agriculture and social economy. This study adopted the minimum per capita area method, ESPR (Exposure-Sensitivity-Pressure-Response) vulnerability assessment model, grey prediction model, and GIS spatial analysis. Furthermore, based on the characteristics of water resource constraints in the arid zone, Manas County was used as the study area. By exploring and analyzing the area of land retreat, through identifying its occurrence and position, the spatial zoning layout of land retreat can be realized to guarantee the effective implementation of water retreat and reduction. The following points were noted from the results: (1) the upper and lower limits of the area of receding land in Manas County were measured using the minimum per capita area method and the principle of balancing water supply and demand. The receding land in Manas County measured 16,493.68–20,749.90 hm2, which accounted for 24.31–30.58% of the total area of cultivated land. (2) The results obtained from constructing the ESPR vulnerability assessment model, used to assess the vulnerability of cultivated land in Manas County, showed that the overall vulnerability of cultivated land in Manas County was high, with 94.74% of the county’s cultivated land being moderately vulnerable or worse, which necessitates the optimization of land use. (3) The area of cultivated land withdrawal under the water resource constraint was used as a constraint for the withdrawal of cultivated land. Based on the evaluation of the vulnerability of cultivated land, with the results arranged from small to large, it was concluded that the area of cultivated land withdrawal in Manas County could reach up to 16,787.34 hm2. There are four types of cultivated land withdrawals: desertified withdrawal, saline withdrawal, groundwater overexploitation withdrawal, and soil contamination withdrawal. The results of this study can provide a reference for Manas County to scientifically formulate a reasonable and orderly withdrawal system of farmland to reduce water use.

Multi-Source Remote Sensing Data for Lake Change Detection in Xinjiang, China

Lake water resources in arid areas play an important role in regional resource and environmental management. Therefore, to master the dynamic changes in lake water resources in arid areas, the laser altimetry satellite and land resource satellite were used to interpret the changes in water level and the areas of alpine lakes and non-alpine lakes. The dynamic changes in the lake and their relationship with glacial meltwater, precipitation, and runoff of the lake basin were analyzed using the unary linear regression equation, the ratio of glacier area to lake area (G–L ratio), and the ratio of lake basin area to lake area (supply coefficient). The results were as follows: the changes in alpine lakes were closely related to the supply coefficient (basin/lake area ratio) but weakly related to the G–L ratio (glacier/lake area ratio). In addition, the spatial pattern of lake change was consistent with that of climate change. There was a strong correlation between the lake, precipitation, and temperature during the snowmelt period. Thus, it can be seen that the changes in the lake were caused by precipitation, glacial melt, snowmelt, and other multi-factors. Therefore, this study on the changes in water resources in different types of lakes and their influencing factors provides data support for water resources managers to evaluate the health and sustainable utilization of the ecological environment.

Spatial Distribution of Groundwater Quality Parameters in Al-Najaf City Using GIS and Geostatistics Techniques

The scarcity of water resources in arid areas, as well as the impact of agricultural and human activities on groundwater quantity and quality, need a greater emphasis on these resource quality evaluations. In this study, the groundwater quality in the governorate of Al-Najaf was investigated using geostatistical methods based on the kriging interpolation approach to interpolate values in regions where real data was not available, also groundwater samples were evaluated based on a variety of qualitative parameters. Linear Gaussian, exponential, stable, and quadratic were the semivariogram models the study examined, and archGIS software was extensively utilized to map the investigated data. The study concluded that the groundwater in this area is unsuitable neither for drinking purposes nor in most of the industries according to the Iraqi specifications. Wilcox and United States Salinity Laboratory (USSL) diagrams were used to analyse the accessible water wells in the area. The diagrams depicted that 95.8 percent of the available well water in the research region is unsuitable for irrigation due to the extremely high salinity and continued application of such water may result in the development of salt soils. Spatial examination of groundwater revealed serious problems with almost all groundwater parameters in terms of water appropriateness for drinking, irrigation, and other purposes.

北京山区干旱胁迫下侧柏叶片水分吸收策略

PDF HTML阅读 XML下载 导出引用 引用提醒 北京山区干旱胁迫下侧柏叶片水分吸收策略 DOI: 10.5846/stxb202010072553 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（41877152）；林果业生态环境功能提升协同创新中心（市级）项目（CEFF-PXM2019_014207_000099） Leaf water absorption of Platycladus orientalis under drought stress in Beijing Author: Affiliation: Fund Project: National Natural Science( 41877152)；Project of Collaborative Innovation Center (municipal level) for forest and Fruit Industry ecological Environment Function Improvement( CEFF-PXM2019_014207_000099) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:干旱与半干旱地区，水分是限制树木生长的重要影响因子。由于降水稀缺且分配不均，叶片吸收水分是此地区树木吸收和利用小量级降水和凝结水的主要方式。北京山区处于易旱少雨的生态脆弱地带，森林植被经常遭受干旱胁迫，所以对该地区的森林系统而言，叶片直接吸收利用截留的降雨是干旱时期树木获得水分的重要途径。基于野外对比控制试验和室内盆栽模拟试验，选取北京山区的主要造林树种侧柏为研究对象，进行利用天然降雨与模拟降雨试验，研究降雨前后侧柏叶片吸水特征，探究侧柏在干旱环境下如何通过叶片吸水缓解干旱胁迫。结果表明：当侧柏长期处于干旱胁迫状态时，叶片可以利用降雨，从中获益用来缓解树木的干旱胁迫状态；叶片的吸水能力与降雨强度呈正相关关系，与土壤含水率呈负相关关系；重度干旱下侧柏植株在降雨强度为15 mm/h时叶片吸水现象最明显，叶水势变化最大为（1.18±0.17） MPa，叶片含水率变化最大为（8.47±1.00） mg/cm2；当土壤水率高于20.8%时，基本不发生叶片吸水现象。试验结果说明在干旱地区叶片吸水是树木除根系吸水外的重要水分来源方式，并且对干旱地区有效利用短缺水资源，减轻植物水分亏缺具有重要意义。 Abstract:In arid and semi-arid areas, water is an important factor that restricts the growth of trees. Due to the scarcity and uneven distribution of precipitation, the leaf absorption of water is the main way for trees in this area to absorb and use small amounts of precipitation and condensate. The mountainous area of Beijing is located in an ecologically fragile zone prone to drought and less rain. Forest vegetation often suffers from drought stress. Therefore, for the forest system in this area, the direct absorption and use of intercepted rainfall by leaves is an important way for trees to obtain water during dry periods. Based on field comparative control experiments and indoor pot plant simulation experiments, Platycladus orientalis, the main afforestation tree species in Beijing mountainous areas, was selected as the research object. Natural rainfall and simulated rainfall experiments were carried out to study the water absorption characteristics of Platycladus orientalis leaf before and after rainfall, and explore how Platycladus orientalis under arid environment alleviate drought stress by absorbing water by leaves. The results show that when Platycladus orientalis is under drought stress for a long time, the leaves can use rainfall to alleviate the drought stress of trees; the water absorption capacity of leaves is positively correlated with rainfall intensity and negatively correlated with soil moisture content; Under severe drought, Platycladus orientalis plants have the most obvious water absorption phenomenon when the rainfall intensity is 15 mm/h. The maximum change in leaf water potential is (1.18±0.17) MPa, and the maximum change in leaf water content is (8.47±1.00) mg/cm2; When the soil moisture content is higher than 20.8%, there is basically no water absorption by the blades. The test results show that leaf water absorption in arid areas is an important source of water for trees in addition to root water absorption, and it is of great significance for effective use of scarce water resources in arid areas and alleviating plant water deficit. 参考文献 相似文献 引证文献

Impact of landscape dams on river water cycle in urban and peri-urban areas in the Shiyang River Basin: Evidence obtained from hydrogen and oxygen isotopes

To meet the needs of human recreation and provide community amenities, landscape dams (i.e., water retaining structures for intercepting river water in cities and surrounding areas, which are mainly used to create an urban landscape environment) are built in urban and peri-urban areas worldwide. The construction of these dams, however, may adversely affect the local and regional water cycle. We collected water samples from 2015 to 2019 from different water bodies in urban and peri-urban areas traversing the middle and upper reaches of Shiyang River Basin in the arid area of Central Asia to analyze their isotopic characteristics. Meanwhile, field surveys as well as meteorological, hydrological, and remote-sensing data were added to evaluate the hydrologic effects of urban landscape dams on a watershed scale in an arid region with scarce water resources and fragile ecosystems. Isotopic values of landscape water were more enriched than that of natural river. The result of the evaporation loss ratio showed that the landscape water was 0–5% higher. Moreover, the cumulative effect of multiple landscape dams leads to a great loss of water resources in arid areas. The study also demonstrated that evaporation is a vital factor in causing change in the isotope composition of the landscape water in the Shiyang River Basin. The interaction between surface water and groundwater was frequent within the landscape dam area wherein groundwater was mainly recharged by surface water leakage. Sufficient attention should be given to the evaporation, leakage, local precipitation, and groundwater changes caused by the impoundment of landscape dams. Thus, the potentially adverse effects of urban landscape dams in arid regions should be highly considered in long-term water-resources sustainability planning.

Research Status of Brackish Water Desalination Technology

The serious salinization of farmland soil and the shortage of water resources in arid areas are becoming more and more serious; In order to solve the problem of shortage of fresh water resources, find a resource that can be converted into fresh water; Brackish water is derived from farmland saline alkali land. Brackish water desalination technology has increased interest in scientists' research. However, brackish water can be used as an effective substitute for freshwater conversion because of its low salt concentration and can also be widely used in many water deficient countries. However, partial or total desalting of brackish water is essential to meet the water quality requirements of production and life. The selection of appropriate water resources desalination technology needs to understand the operation methods and technical means of the existing brackish water desalination process. Proper combination of desalination technologies can improve the efficiency of brackish water desalination. This review provides the latest advances in data, materials and categories that can help select and design requirements for specific applications.

Quantitative Detection and Attribution of Groundwater Level Variations in the Amu Darya Delta

In the past few decades, the shrinkage of the Aral Sea is one of the biggest ecological catastrophes caused by human activity. To quantify the joint impact of both human activities and climate change on groundwater, the spatiotemporal groundwater dynamic characteristics in the Amu Darya Delta of the Aral Sea from 1999 to 2017 were analyzed, using the groundwater level, climate conditions, remote sensing data, and irrigation information. Statistics analysis was adopted to analyze the trend of groundwater variation, including intensity, periodicity, spatial structure, while the Pearson correlation analysis and principal component analysis (PCA) were used to quantify the impact of climate change and human activities on the variabilities of the groundwater level. Results reveal that the local groundwater dynamic has varied considerably. From 1999 to 2002, the groundwater level dropped from −189 cm to −350 cm. Until 2017, the groundwater level rose back to −211 cm with fluctuation. Seasonally, the fluctuation period of groundwater level and irrigation water was similar, both were about 18 months. Spatially, the groundwater level kept stable within the irrigation area and bare land but fluctuated drastically around the irrigation area. The Pearson correlation analysis reveals that the dynamic of the groundwater level is closely related to irrigation activity within the irrigation area (Nukus: −0.583), while for the place adjacent to the Aral Sea, the groundwater level is closely related to the Large Aral Sea water level (Muynak: 0.355). The results of PCA showed that the cumulative contribution rate of the first three components exceeds 85%. The study reveals that human activities have a great impact on groundwater, effective management, and the development of water resources in arid areas is an essential prerequisite for ecological protection.

Response of groundwater to the process of reservoirs group regulation and storage in Manas River Basin in Xinjiang

Reservoir regulation and storage is the main approach to alleviate the water pressure caused by the uneven spatial and temporal distribution of surface water resources in arid areas of northwest China. While the regulation and storage of the reservoir affect the conditions of recharge and discharge of groundwater, the process of regional surface-groundwater transformation tends to be complicated. The Manas River basin that lies on the northern slope of Tianshan Mountain in Northwest China was taken in this study as a case. A numerical model of groundwater in basin plain area was established, and the influence of reservoir regulation on groundwater level was studied. The results showed that the total recharge of groundwater in the study area was 75.539 million m3, the total discharge of groundwater was 82.66 million m3, and the groundwater in the study area was in a negative equilibrium state, with a difference of – 69.27 million m3. The water balance method was used to verify the comparison. The total recharge of groundwater was 74.34 million m3, the total discharge of groundwater was 80.726 million m3, and the calculation result of the numerical simulation of the supplementary displacement was 63.82 million m3, basically consistent with the calculation result of the water balance method. The reservoir storage method has obvious changes to the groundwater level around the reservoir. The simulation results of groundwater numerical model showed that when the reservoir was in normal operation, the leakage of the reservoir was 27.35 million m3; when the reservoir was operated at low water level, the leakage of the reservoir was the smallest, 13.47 million m3. The reservoir has the largest amount of leakage of 41.85 million m3 when operated at water storage level. When the reservoir was operated at the lowest water level, the groundwater level around the reservoir was declining compare to the normal operating water level. The maximum drop of the groundwater observation well was 2.1 m, and the maximum monthly average was 0.99 m. When the reservoir was operating at the normal water storage level, the water level of the groundwater around the reservoir has increased compare to the normal operating water level. The maximum increase of the groundwater observation well was 1.5 m, and the maximum monthly average increase was 0.78 m. The influence of the reservoir on the groundwater level was 2000 m upstream and 12000 m downstream. The research conclusions can provide a scientific reference for the development, utilization and management of regional groundwater. Keywords: Manas River Basin, water balance, numerical simulation; reservoir regulating, groundwater DOI: 10.25165/j.ijabe.20201301.4866 Citation: Liu B, He X L. Response of groundwater to the process of reservoirs group regulation and storage in Manas River Basin in Xinjiang. Int J Agric & Biol Eng, 2020; 13(1): 224–233.

Hydrochemistry and multi-isotope study of the waters from Hanlé-Gaggadé grabens (Republic of Djibouti, East African Rift System): A low-enthalpy geothermal resource from a transboundary aquifer

Water from ten thermal springs, five drinking-water boreholes and one hand-dug well from Hanlé-Gaggadé grabens has been analyzed for major-minor hydrogeochemical parameters and multi-isotope composition: δ2H(H2O), δ18O(H2O), δ18O(SO42−), δ34S(SO42−), δ13C(DIC), 14C(DIC), and δ11B. The interaction of the thermal water with both silicic (basaltic) and sedimentary rocks and its low enthalpy (T ≤ 150 °C) regime make this area an optimal site for testing chemical and isotope geothermometers and optimizing them for similar difficult cases. In this study, the use of radiogenic carbon (14C) reveals that the age of the deep aquifer is between 12,500 and 8700 years ago (late Pleistocene/early-to-mid Holocene), which places it within the East African Humid Period. The oxygen and hydrogen stable isotope ratios of the water molecules, δ2H(H2O), δ18O(H2O), show common characteristics between the groundwater from this area and that of groundwater from nearby local lakes (Asal-Abhé) and palaeolakes (Sakalol-Hanlé-Gaggadé-Dobi), which were interconnected during that period to form the terminal Awash River Basin. The comparison of these aquifers within the transboundary aquifer located between northeast Ethiopia and Djibouti helps to reconstruct both the palaeoenvironmental history and the hydrogeochemical characteristics of this regional aquifer. At present, these data are poorly defined, but it is of fundamental importance for the constructive use of water resources in arid areas. Finally, a conceptual model was proposed for the Hanlé-Gaggadé low-enthalpy geothermal system on the basis of the geochemical and isotope data on the thermal and non-thermal groundwaters combined with geological and tectonic information and the results of recent geophysical studies.

Response of groundwater to the process of reservoirs group regulation and storage in Manas River Basin in Xinjiang

Reservoir regulation and storage is the main approach to alleviate the water pressure caused by the uneven spatial and temporal distribution of surface water resources in arid areas of northwest China. While the regulation and storage of the reservoir affect the conditions of recharge and discharge of groundwater, the process of regional surface-groundwater transformation tends to be complicated. The Manas River basin that lies on the northern slope of Tianshan Mountain in Northwest China was taken in this study as a case. A numerical model of groundwater in basin plain area was established, and the influence of reservoir regulation on groundwater level was studied. The results showed that the total recharge of groundwater in the study area was 75.539 million m3, the total discharge of groundwater was 82.66 million m3, and the groundwater in the study area was in a negative equilibrium state, with a difference of – 69.27 million m3. The water balance method was used to verify the comparison. The total recharge of groundwater was 74.34 million m3, the total discharge of groundwater was 80.726 million m3, and the calculation result of the numerical simulation of the supplementary displacement was 63.82 million m3, basically consistent with the calculation result of the water balance method. The reservoir storage method has obvious changes to the groundwater level around the reservoir. The simulation results of groundwater numerical model showed that when the reservoir was in normal operation, the leakage of the reservoir was 27.35 million m3; when the reservoir was operated at low water level, the leakage of the reservoir was the smallest, 13.47 million m3. The reservoir has the largest amount of leakage of 41.85 million m3 when operated at water storage level. When the reservoir was operated at the lowest water level, the groundwater level around the reservoir was declining compare to the normal operating water level. The maximum drop of the groundwater observation well was 2.1 m, and the maximum monthly average was 0.99 m. When the reservoir was operating at the normal water storage level, the water level of the groundwater around the reservoir has increased compare to the normal operating water level. The maximum increase of the groundwater observation well was 1.5 m, and the maximum monthly average increase was 0.78 m. The influence of the reservoir on the groundwater level was 2000 m upstream and 12000 m downstream. The research conclusions can provide a scientific reference for the development, utilization and management of regional groundwater. Keywords: Manas River Basin, water balance, numerical simulation; reservoir regulating, groundwater DOI: 10.25165/j.ijabe.20201301.4866 Citation: Liu B, He X L. Response of groundwater to the process of reservoirs group regulation and storage in Manas River Basin in Xinjiang. Int J Agric & Biol Eng, 2020; 13(1): 224–233.