Water Shortage Areas Research Articles

Forest restoration, resources sustainable use and high-quality sustainable management

As the economy develops and the population increases, there is an increasing demand for goods such as timber, food, medicine, and so on, and ecological services such as fresh water and the environment. Because goods and services produced by the original forest cannot meet the increasing need of people, so most of the original forest has become farmland, plantation, and grass. In the process of Forest restoration, a lot of exotic plants was introduced to produce special products and service. As exotic plants grow, vegetation declines, and crop failure will happen in dry years or resource waste in wet years. In order to solve these problems, Years of theoretical research and investigation in fixed positions have shown that there is a soil water resources use limit by plants and the soil water vegetation carrying capacity in the process of vegetation restoration. When the soil water resources in the range of the maximum infiltration depth are equal to the soil water resources use limit by plants, the plant water relation enters the key period of plant water relation regulation. If existing plant density is more than the soil water vegetation carrying capacity in the key period of plant water relation regulation, the plant water relation has to be regulated on the soil water vegetation carrying capacity to get maximal yield and service and realize high-quality sustainable management of forest vegetation in a water shortage area.

Temporal–Spatial Variations in the Economic Value Produced by Environmental Flows in a Water Shortage Area in Northwest China

Scientific and accurate assessments of the economic value produced by environmental flows are an important basis for the protection of environmental flows by means of economics. Because of the temporal and spatial variation characteristics of environmental flows, it is more appropriate to study the economic value produced by environmental flows using a temporal–spatial scale rather than static calculations. In the present study, we combine the major influencing factors to establish the temporal–spatial calculation methods of the economic value produced by environmental flows using the assessment techniques of resources and environmental economics. The results obtained for the Wei River show that the annual variation range of the total economic value is CNY 0.30–0.42 billion, and the unit economic value is 0.86–6.40 CNY/m3 during the non-flood season ranging from the years 1980 to 2017. In general, the monthly variation in the total economic value ranges from CNY 0.04 to 0.08 billion, and the unit economic value is 0.94–14.34 CNY/m3. Based on this result, the variation tendency of the total economic value is consistent with the changing trend of the environmental flows occurring in the river; however, the unit economic value presents a reverse pattern. Furthermore, the deficiency of environmental flows can lead to a significant increase in its unit economic value. This method presents a dynamic, small temporal–spatial scale assessment of the economic value produced by environmental flows. It can also provide theoretical support for the ecological compensation of environmental flow protection in rivers present in water shortage areas.

Multi-Objective Lower Irrigation Limit Simulation and Optimization Model for Lycium Barbarum Based on NSGA-III and ANN

Lycium barbarum has rich medicinal value and is an important medicinal and economic tree species in China, with an annual output value of 21 billion RMB. The yield and the quality of Lycium barbarum dry fruit are the crucial issues that affect the cultivation of Lycium barbarum and the income of farmers in the Ningxia water shortage area. According to the local acquisition standard of Lycium barbarum, the amount of dry fruit per 50 g (ADF-50) is the key factor in evaluating the quality and determining the purchase price. In order to optimize the irrigation lower limit of automatic drip irrigation system with multiple objectives, the yield and ADF-50 are selected to be optimal objectives. The lower irrigation limits of the automatic drip irrigation system in the full flowering stage, the summer fruiting stage, and the early autumn fruiting stage are optimized by the third generation of non-dominated sorting genetic algorithm (NSGA-III) in this paper. The mathematical relationships between irrigation lower limit and irrigation quantity, irrigation amount, yield, and ADF-50 were established by the water balance model, water production function (WPF), and artificial neural network model (ANN), respectively. The accuracy of the water balance model and ANN were verified by experiments. The experiments and optimization results show that: (1) irrigation quantity and ADF-50 calculated by the water balance model and ANN are accurate, and their Nash–Sutcliffe coefficient are 0.83 and 0.66; (2) In a certain range of irrigation quantity, ADF-50 and Lycium barbarum yield show competitive relation. By solving the NSGA-III optimization model, the lower irrigation limits schemes, which tend to different objectives, and a compromise scheme can be obtained; (3) Compared with the original lower limit of irrigation water, the compromise scheme’s yield and quality of Lycium barbarum are improved 10.7% and 8.8% respectively. The results show that the automatic drip irrigation system’s lower irrigation limit scheme optimized by the model can improve not only the yield but also the quality of Lycium barbarum. This provides a new idea for establishing the irrigation lower limit of the automatic drip irrigation system in the Lycium barbarum planting area.

Study on deformation control of overlying strata in short-wall coordinated filling mining of thick coal seam under aquifer

The mining of coal resources and the protection of water resources are often in opposition, and this contradiction is more prominent in the mining of thick coal seams due to the difficulty of controlling the overburden deformation. Based on the mining conditions of thick coal seam under the main aquifer of a coal mine in the water shortage area of Northwest China, this paper puts forward the short-wall coordinated filling mining (SCFM) of thick coal seam. The stress analysis of the overall structure consisting of the top and bottom plates, coal pillars and filler at each stage of the mining process was carried out, the length of the short-walled working face suitable for this coal mine was derived, and the key parameters for the mining of the three pan areas of the mine were designed. The analysis results show that the sensitivity of the maximum tensile stress in the roof to the length of the working face is better than the filling rate in the case of short-walled working face arrangement. When the design coal mine working face length is 40 m and the filling rate is 95%, the overburden fissure development height can be controlled to 58.45 m after the whole area of three pan area is retrieved. It is verified by the downhole injection method that the requirement of non-conducting aquifer is satisfied after using SCFM. The research in this paper is of great significance to achieve safe and efficient recovery of coal resources and water conservation under strongly water-rich rock formations.

Smart irrigation planning in water deficit area (case study: Pench Irrigation Project, India)

Smart irrigation planning in water deficit area (case study: Pench Irrigation Project, India)

Sustainable Hierarchical-Pored PAAS-PNIPAAm Hydrogel with Core-Shell Structure Tailored for Highly Efficient Atmospheric Water Harvesting.

As an effective way to obtain freshwater resources, atmospheric water harvesting (AWH) technology has been a wide concern of researchers. Therefore, hydrogels gradually become key materials for atmospheric water harvesters due to their high specific surface area and three-dimensional porous structure. Here, we construct a core-shell hydrogel-based atmospheric water harvesting material consisting of a shell sodium polyacrylate (PAAS) hydrogel with an open pore structure and a core thermosensitive poly N-isopropylacrylamide (PNIPAAm) hydrogel with a large pore size. Theoretically, the mutual synergistic hygroscopic effect between the core layer and the shell layer accelerates the capture, transport, and storage of moisture to achieve continuous and high-capacity moisture adsorption. Simultaneously, the integration of polydopamine (PDA) with the hydrogel realizes solar-driven photothermal evaporation. Therefore, the prepared core-shell hydrogel material possesses great advantages in water adsorption capacity and water desorption capacity with an adsorption of 2.76 g g-1 (90% RH) and a desorption of 1.42 kg m-2 h-1. Additionally, the core-shell structure hydrogel collects 1.31 g g-1 day-1 of fresh water in outdoor experiments, which verifies that this core-shell hydrogel with integrated photothermal properties can capture moisture in a wide range of humidity without any external energy consumption, can further sustainably obtain fresh water in remote water-shortage areas.

Forest restoration and Sustainable of Soil Water Resources and High-quality sustainable management

Along with economic development and an increase in population, there is an increasing demand for goods such as timber, food, medicine, and so on, and ecological services such as fresh water and the environment. Because goods and service produced by the original forest cannot meet the increasing need of people, so most of the original forest has become farmland, plantation, and grass, and a lot of exotic plants was introduced to produce special products and service. As introduced plants grow, vegetation decline and crop failure happen in dry years or resource waste in wet years. In order to solve these problems, Years of theoretical research and investigation in fixed positions have shown that there is a soil water resources use limit by plants and the soil water vegetation carrying capacity in the process of vegetation restoration. When the soil water resources in the range of the maximum infiltration depth are equal to soil water resources use limit by plants, the plant water relation enters the key period of plant water relation regulation. If existing plant density is more than the soil water vegetation carrying capacity in the key period of plant water relation regulation, the plant water relation has to be regulated on the soil water vegetation carrying capacity to get maximal yield and service and realize high-quality sustainable management of forest vegetation in a water shortage area.

A resilience-based approach for water resources management over a typical agricultural region in Northwest China under water-energy-food nexus

Agriculture in the arid regions must take effective measures to cope with the constant challenges brought by climate warming and possible resource attenuation. As a typical agriculture region in Northwest China, the water resources resilience has been under varying degrees of pressure over the past two decades. To mitigate the stress of water resources, this study explored the optimal arrangement of agronomic and water-saving measures in farmland system under water-energy-food nexus. The finer simulations with reflecting the spatial heterogeneity was realized by employing G-AquaCrop model. Both water resources resilience evaluation model and the water-energy-food nexus coupling coordination evaluation model were constructed for the farmland system in the arid region. The results show that the combination of plastic film mulching and drip irrigation measures, among nine scenario sets of the different agronomic and water-saving measures, can be largely implemented in the Gaotai, Linze, Ganzhou and Minle Counties in Zhangye, which are mainly distributed in the lower reaches of the Heihe River basin in Northwest China. Alternative diversified management could be adopted elsewhere in the basin. The measures obtained have the merit of addressing the challenges of future climate change, especially for the agricultural regions in water-shortage area.

Can Collecting Water Fees Really Promote Agricultural Water-Saving? Evidence from Seasonal Water Shortage Areas in South China

Under the influence of the extreme climate, South China frequently experiences a seasonally arid climate, resulting in seasonal water shortages, and threatening local food and water security. To cope with climate change, agricultural water-saving is inevitable. However, compared with the North, South China is rich in water resources, farmers’ water-saving awareness is weak, and most areas do not charge water fees, so it is difficult to promote agricultural water-saving; therefore, farmers’ agricultural water-saving behavior is worth discussing. Based on a survey and empirical analysis, this study identifies the key determinants of farmers’ agricultural water-saving behavior, particularly to verify whether collecting water fees helps to promote agricultural water-saving. A structured questionnaire was administered to a random sample of 660 farmers in South China with seasonal water shortage. A binary logistic regression model was used to examine the determinants. The results revealed that 15.30% (101) of farmers paid agricultural water fees, 26.97% (178) of farmers had agricultural water-saving behavior, and among these, 43.82% (78) of farmers paid agricultural water fees. The results indicated that water fee collecting, water resource dependence, agricultural water service satisfaction, and water-saving policy publicity positively and significantly influenced farmers’ agricultural water-saving behavior, while farm size and age of household head showed a negative influence. Results also revealed that collecting water fees can indeed promote agricultural water-saving in seasonal water shortage areas of South China. This study recommends that policy makers take measures to improve agricultural water charges policies, strengthen irrigation services, and increase the publicity of agricultural water-saving policies.

Spatiotemporal heterogeneity and attributions of streamflow and baseflow changes across the headstreams of the Tarim River Basin, Northwest China

Understanding spatiotemporal heterogeneity of streamflow and baseflow and revealing their changes contributed by climatic factors and human activities in the alpine region of inland river basin are critical for regional water management. However, the hydrology heterogeneity in the alpine region has remained unclear, which limits the scientific understanding of the interaction mechanism between the hydrological cycle and terrain, and further constrains the effective utilization of regional water resources in the water-shortage areas. In this study, the hydrological process and regimes for headstreams of Tarim River Basin (HTRB) during 1985–2011 were simulated by the Soil and Water Assessment Tool. We systematically characterized the spatial and temporal patterns of streamflow and baseflow through geostatistical and trend analyses, and subsequently investigated their heterogeneity responses to climate change and human activities at different sub-basins and elevation zones. Results show that the spatial distributions of streamflow and baseflow are highly related to terrain and river direction. Increased trends in precipitation enhanced with altitude, whereas decreased trends in potential evapotranspiration (PET) weakened with altitude, meanwhile, increased trends in streamflow and baseflow of HTRB are most pronounced in mid-altitude areas during 1985–2011. The climate elasticities of streamflow and baseflow are highly reliant on the altitudinal gradient. Increases in streamflow and baseflow in high-lying areas are more sensitive to precipitation variation, while they are more sensitive to PET change in low-lying areas. The magnitude and change rate with altitude bands of the precipitation has greater effects on streamflow and baseflow variations than those of PET. Furthermore, the percentage of sub-basins where climate changes dominate streamflow variation in each elevation band increases with height but decreases abruptly at elevations above 5000 m. The percentage of sub-basins where climate changes dominate baseflow variations gradually decreases in elevation bands above 3000 m. Our results indicate that climate change rather than human activities dominants the variation in streamflow and baseflow in most sub-basins and elevation bands.

Vegetation photosynthesis changes and response to water constraints in the Yangtze River and Yellow River Basin, China

• Spatio-temporal pattern of annual maximum GOSIF were evaluated. • Water deficit area had an expanding trend, water surplus area had a shrinking trend. • The r GOSIF-scPDSI and r GOSIF-SPEI03 variations can be explained by atmospheric CO 2 . Satellite remotely sensed solar-induced chlorophyll fluorescence (SIF) is an effective index for detecting the ecosystem-level photosynthetic capacity, yet it remains poorly understood how vegetation photosynthesis responds to water constraints. This study determined the spatial–temporal changes and water constraints on vegetation photosynthesis based on the Self-Calibrated Palmer Drought Severity Index (scPDSI), Standardized Precipitation Evapotranspiration Index (SPEI) and global Orbiting Carbon Observatory-2 SIF (GOSIF) data in the Yangtze River and Yellow River basin between 2000 and 2018. The results showed that annual maximum GOSIF steadily increased across the whole basin ( slope = 0.0031 W m -2 μm -1 sr -1 a -1 , P < 0.001). The maximum increasing trend was found in the semi-arid region (0.0034 W m -2 μm -1 sr -1 a -1 , P < 0.001). The highest value of annual maximum GOSIF was found in the Qinling-Daba Mountains along with Hengduan Mountain. The lowest GOSIF was found in the western portions of the Loess Plateau and the source region of Yangtze River and Yellow River. Positive correlations between satellite GOSIF and water availability were particularly strong in the Loess Plateaus; in contrast, negative correlations were found in the Hengduan Mountains. The area of water deficit displayed a significant trend towards expansion ( slope = 1.539 % a -1 and 0.898 % a -1 , P < 0.05), while water surplus areas significantly shrank ( slope = 0.847 % a -1 and 0.584 % a -1 , P < 0.05) in the Yangtze River and Yellow River basin. Atmospheric CO 2 concentration and precipitation were the dominant drivers for the water deficit regions, while atmospheric CO 2 concentration and temperature were the dominant drivers for the water surplus regions. This study emphasizes the effect of water constraints on regional vegetation photosynthesis under global warming conditions and patterns of greening.

Effect of Exogenous Application of Nicotinic Acid on Morpho-Physiological Characteristics of Hordeum vulgare L. under Water Stress.

Abiotic stresses, such as high temperature and drought conditions, greatly influence the development of plants and the quality and quantity of products. Barley (Hordeum vulgare L.) crop production is largely impacted by drought, affecting growth, yield, and ultimately the productivity of the crop in hot arid/semi-arid conditions. The current pot experiment was directed to observe the outcome of nicotinic acid (NA) treatments on barley’s physiological, biochemical, and production attributes at two capacity levels, i.e., 100% normal range and withholding water stress. Randomized complete block design (RCBD) was used during the experimentation with the two-factor factorial arrangement. NA was applied exogenously by two different methods, i.e., foliar and soil application (fertigation). NA solution contained various application levels, such as T1 = control, foliar applications (T2 = 0.7368 gL−1, T3 = 1.477 gL−1, T4 = 2.2159 gL−1), and soil applications (T5 = 0.4924 gL−1, T6 = 0.9848 gL−1, and T7 = 1.4773 gL−1). Results depicted that, overall, foliar treatments showed better effects than control and soil treatments. Plant growth was preeminent under T4 treatment, such as plant height (71.07 cm), relative water content (84.0%), leaf water potential (39.73-MPa), leaf area index (36.53 cm2), biological yield (15.10 kgha−1), grain yield (14.40 kgha−1), harvest index (57.70%), catalase (1.54 mmolg−1FW−1), peroxidase (1.90 g−1FWmin−1), and superoxide dismutase (52.60 µgFW−1) were superior under T4 treatment. Soil plant analysis development (54.13 µgcm−2) value was also higher under T4 treatment and lowest under T7 treatment. In conclusion, NA-treated plants were more successful in maintaining growth attributes than non-treated plants; therefore, the NA foliar treatment at the rate of 2.2159 gL−1 is suggested to find economical crop yield under drought conditions. The present study would contribute significantly to improving the drought tolerance potential of barley through exogenous NA supply in water deficit areas.

Study on Ecological Allocation of Mine Water in Mining Area Based on Long-term Rainfall Forecast

Based on the mine water produced by mining, to improve the ecological environment, the optimal allocation of mine water resources is studied. To reduce the uncertainty of the calculation results of ecological water demand, the wolf colony algorithm neural network model is used for long-term rainfall forecast. Combined with the forecast annual rainfall, the ecological water demand is classified and calculated. The results show that the ecological water demand based on rainfall forecast can reduce the allocation of water resources in wet years to ecological, so that the surplus water resources can be used in industries, irrigation, and other aspects that can create economic benefits, and improve the utilization efficiency of water resources. The ecological allocation model of mine water based on long-term rainfall forecast can reduce the uncertainty of regional water resources allocation based on rainfall forecast, which has good guiding significance and practical value for the optimal allocation of water resources in arid and water shortage areas.

Research on Engineering Application of Flue Gas Water Lifting Technology

The application of flue gas water lifting technology in thermal power plants can effectively balance the contradiction between thermal power development and water source protection in water shortage areas. However, at present, the engineering application of flue gas water lifting technology is limited, and the comprehensive research relying on field application is lacking. Based on the actual commissioning and performance test of flue gas water lifting system of a 660MW thermal power unit, the project trial operation and water-saving capacity are systematically studied in this paper. Through the system commissioning test, it is found that the water filling process should be considered in the design of circulating cooling water system in the form of closed water, and the operation safety can be improved by setting expansion tank and adding drainage points. The quantity of delivery water is affected by ambient temperature, circulating water quantity and cooling water temperature. Through the performance test, it is found that flue gas water lifting technology can meet the demand of water replenishment for desulfurization tower and has a positive effect on the suppression of flue gas side dust level.

Comparing the Effects of Different Organic Mulching Materials on Weed Control, Soil Moisture Conservation, and Wheat (Triticum Aestivum) Productivity in the Moisture Deficit Areas

Wheat (Triticum aestivum) productivity, in water deficit areas such as Ethiopia, is threatened by low soil fertility, weed infestation and moisture stress. Organic Mulch was believed to avert these challenges but only limited scientific information, on its level of effects (crop yield, soil moisture conservation and weed control), was available. Hence, an experiment was carried out on Cambisols in Tigray/Ethiopia during the 2019/20 growing season following a Randomized Complete Block Design (RCBD). Four organic mulch types (maize stalk, sorghum stalk, wheat straw, and finger millet straw), each at the rates of 2 ton ha-1 were compared against the control (no mulch). Their economic visibility was evaluated using partial budget analysis. Our experimental results revealed that mulched plots had a significantly higher weed control efficiency, soil moisture content, grain yield, and net benefit as compared to the control. Mulching in general improved Wheat grain yield by 26.8%, soil moisture (at 0 – 20 cm) by 73.7%, weed control efficiency by 57.4%, and net benefit by 19.7% as compared to the control. Maize and sorghum stover mulches were the most profitable mulch types which increased net benefit by 38.2 and 27.6%, respectively. It can be concluded that organic mulching with Maize and Sorghum stover is a good option to improve crop production, soil moisture and reduce weed infestation in the moisture deficit areas.

Analysis of agriculture water pricing reform in a water-deficit area of Northwest China

Abstract Northwest China frequently experiences significant droughts and water shortages. To better balance the supply and demand, and provide sufficient funds for water resource projects, this study applied a computable general equilibrium model to construct an agricultural water pricing policy model that depends on the crops' economic value and regional water use characteristics. Wuwei City in Gansu Province was used as a case study to test the model. Three agricultural water price increase policies and three supporting subsidy policies were developed. The study quantitatively investigated the impact of these policies on the agricultural economy, water use, and efficiency of water use from different water sources. The results indicated that water pricing reform promotes water conservation and improves water use efficiency. Subsidies can reduce the negative impact of water pricing policies on the agricultural economy. Economic crops (e.g. vegetables) are more sensitive to water prices compared to food crops (e.g. wheat). Finally, to the best of our knowledge, this study provided the best water pricing reform scenario expected to be the most effective for local development.

Evaluation of Different Furrow Irrigation Systems and Water Levels on Potato at Oda Sirba Scheme

Water availability is becoming a critical issue in Ethiopia so that preferable irrigation technologies need to be developed and water productivity of irrigated crops through water management is a vital option in water shortage areas. Hence, the objective of the study was to improve potato tuber production through the application of different irrigation system and deficit irrigation application under highland climatic condition.

Categories and Application Fields and Manufacturing Process and Action Mechanism of Water Retaining Agent

Water retaining agent (WRA) is a kind of functional polymer material with strong water absorption capacity. It can absorb and release water repeatedly and is often used for crop growth in water shortage areas. It is of great significance to the development of water-saving agriculture. There are many kinds of water retaining agents, and with the development of science and technology, the raw materials for making water retaining agents tend to be diversified. And they are more and more widely used in many fields closely related to our life, such as industry, food production, medical treatment, and greening, and the manufacturing process is more and more mature. In addition, the water absorption capacity of water retaining agent is not only related to its own components but also related to the external environment. The water absorption mechanism and the factors affecting water absorption capacity of water retaining agent were explored as follows.

Long-term saline water irrigation decreased soil organic carbon and inorganic carbon contents

Soil carbon is a key component of ecosystem functions and is crucial to global climate conservation and crop productivity. Saline water irrigation can maintain crop yield inmost world regions of freshwater shortage. However, saline water irrigation may also induce soil salt accumulation, which would result in the change of soil physical or chemical properties. Saline water irrigation’s effect on soil organic carbon (SOC) and soil inorganic carbon (SIC) contents is of little concern. In this study, we irrigated soil with 1 g L−1, 4 g L−1 and 8 g L−1 saline water in a winter-wheat and summer-maize rotation system. After 14 years of irrigation, we sampled soils in a winter wheat and summer maize rotation system, and analyzed soil water, soil salt, SOC, and SIC contents. The results showed that, compared with 1 g L−1 water irrigation, 8 g L−1 saline water irrigation significantly increased soil water and salt contents. Moreover, 8 g L−1 saline water irrigation significantly decreased SOC and SIC contents in the 0–20 cm soil layer (p < 0.05) and mainly decreased SOC content in > 1 mm aggregates and wheat-derived SOC content in bulk soil. In comparison, 4 g L−1 saline water had no significant effect on soil water, soil salt, SOC, and SIC contents. These results indicated that a high concentration of saline water irrigation is harmful for soil carbon sequestration, while a low concentration of saline water did not affect soil carbon sequestration. Thus, using no more than 4 g L−1 saline water irrigation for 14 years can maintain soil carbon storage in the water shortage areas.

Groundwater Dynamic Characteristics with the Ecological Threshold in the Northwest China Oasis

Suitable groundwater level is an important foundation for the stability of the ecological environment, and the healthy development of the social economy, in the arid area of Northwest China. The Manas River Basin is a typical oasis in an arid area, where the problems of salinization and desertification are prominent. By analyzing the variation characteristics of groundwater in the study area from 2013 to 2019 combined with remote sensing technology—according to the theory of capillary water rise and phreatic evaporation—a mathematical calculation model of the ecological threshold is established to determine the ecological groundwater level. The results show that (1) the groundwater level in the study area fluctuates by 0.2–18 m throughout the year, and the variation of groundwater drawdown is 5–35 m from 2013 to 2019; (2) the upper threshold of the ecological groundwater level is 0.82–4.05 m and the lower threshold is 3.35–10.23 m; (3) the ecological water shortage area in the study area is 9755.36 km2, and the groundwater ecological deficit is 105.741 × 108 m3. This study can provide a theoretical basis for the determination of the ecological groundwater level, the optimal allocation of water resources, and ecological environment management in the arid area of Northwest China.