Water Resource Constraints Research Articles

Study on optimization of maize irrigation scheduling in Shaanxi Province

With the impact of climate change in recent years, the instability of precipitation and the increase of evaporation have made water resources in Shaanxi Province more and more stressed. How to maintain stable economic development while ensuring the sustainable development of agriculture within the limited water resources has become an important issue facing Shaanxi Province. This paper analyzes the temporal and spatial distribution characteristics of maize irrigation water requirement in Shaanxi Province based on meteorological data and obtains the ideal irrigation water requirement. However, considering the agricultural water scarcity issue in this region, this paper establishes different water scarcity scenarios, adopts the Jensen model to construct an objective function aimed at minimizing crop yield reduction, and solves it using a genetic algorithm to obtain the optimized maize irrigation scheduling under different water scarcity scenarios. The results analysis indicates the following: (1) The effective rainfall in Shaanxi Province from 1960 to 2019 shows a slight upward trend, while the maize water requirement and maize irrigation water requirement shows a downward trend. (2) The spatial distribution of maize irrigation water requirement in Shaanxi Province decreases gradually from north to south. High-value areas are mainly distributed in the northern regions of Yulin City and Yan’an City in Shanbei. Low-value areas are distributed in Ankang City in Shannan. (3) In the face of water scarcity, spring maize should ensure water use during the middle growth period, fast development period, and initial growth periods. Under the same water scarcity conditions, the yield reduction rate is the highest in Guanzhong, followed by the Shannan, and the lowest in Shanbei. This paper aims to provide a scientific and reasonable optimization plan for maize irrigation in Shaanxi Province by calculating and analyzing the maize irrigation water requirement in Shaanxi Province, combined with optimization tools such as genetic algorithms, to address the challenges brought by water resource constraints.

Exploration of the Path of Industrial Structure Adjustment Forced by the Rigid Constraint of Water Ecology in the Yangtze River Economic Belt

Considering the two-way influence of water ecology and industrial structure, decompose and quantify the water ecological rigidity constraints into water environment constraints and water resources constraints, construct the evaluation system based on the theoretical framework of PSR, and analyze the spatio-temporal evolution characteristics of water ecological rigidity constraints of the Yangtze River Economic Belt from 2010 to 2021 by using the entropy weighting method, the method of catastrophe progression, and the kernel density estimation. Then, putting forward the types of zoning in the Yangtze River Economic Zone through K-means algorithm analysis to explore the rigid constraints of water ecology to force the path of industrial structure adjustment. The results indicate that: (1) the water ecological rigidity constraints show a decreasing trend, and the decreasing amplitude is upstream > downstream > midstream; (2) the water ecological rigidity constraints generally show the characteristic of “gradually decreasing from east to west”, and the degree of regional differences first decreases, then increases, and then decreases again; (3) it can be divided into six types, and the zoning results gradually change from the concentration in the medium-high type and high-high type to the concentration in the low-low type and medium-low type, and the rigidity constraint of water ecology is obviously improved. In light of the findings, the Yangtze River Economic Belt is divided into five types of development regions and further discusses that the industrial restructuring in different zones has different influencing effects on the regional socio-economic development, which provides suggestions for differentiated paths of water ecological protection and industrial restructuring.

Carbon restoration potential on global land under water resource constraints

Carbon restoration potential on global land under water resource constraints

Can agricultural water rights trading promote intensive and economical utilization of water resources in China based on the difference-in-differences model?

IntroductionImproving the level of intensive and economical utilization of water resources is an important step towards water and food security.MethodsBased on China’s provincial panel data from 2015 to 2021, this study uses a difference-in-differences (DID) model to examine the effect of agricultural water rights trading on intensive and economical utilization of water resources.ResultsThe results show that agricultural water rights trading can significantly promote an intensive and economical utilization of water resources at the 1% level, and the results remain valid even after a series of robustness tests. Further analysis indicates that agricultural water rights trading can promote better utilization of water resources by significantly reducing agricultural water consumption at the 1% level and reducing the proportion of agricultural water consumption at the 5% level to optimize water use structure. Moreover, in regions with scarce water resources, strong water resource constraints, more farmland water conservancy projects, and greater economic development, the promoting effect of agricultural water rights trading on the intensive and economical use of water resources is more significant.DiscussionThis study provides evidence of the impact of China’s agricultural water rights trading policy and offers new ideas and experiences to improve China’s water resource utilization efficiency. The contributions of this work are mainly threefold. First, this paper clearly distinguishes the intensive conservation of water resources, presents an evaluation index system, and complements the existing literature on measuring the intensive and economical utilization of water resources. Second, the path of agricultural water rights trading is analyzed to improve the level of intensive and economical utilization of water resources, thus enriching related research on transmission mechanisms. Third, the heterogeneity of the influence of different regional conditions on the level of intensive and economical utilization of water resources is discussed to improve relevant policies.

Optimized Layout of Large-Scale Coal-Fired Power Plant CCUS Projects under Water Resource Constraints in China

Optimized Layout of Large-Scale Coal-Fired Power Plant CCUS Projects under Water Resource Constraints in China

Stable Cycling of Ultrahigh Mass Loaded MnO2 for Low-Cost Sodium-Ion Batteries

Achieving cost-effective and sustainable solutions for large-scale energy storage is critical for advancing the global clean energy transition. The intermittent nature of green energy underscores the inadequacy of current large scale energy storage technologies like pumped hydroelectricity which is susceptible to geographic and water resource constraints, making batteries a prime candidate for this role. Although lithium-ion batteries (LIBs) with high energy and power density are a viable solution, the high cost and uneven distribution of lithium reserves limits the widespread application of LIBs for grid energy storage. Considering these developments and the challenges posed by limited lithium reserves, sustainable and low-cost sodium-ion batteries (SIBs) emerge as a promising alternative.Among the various battery electrode materials, manganese dioxide (MnO2) stands out as a promising choice for large-scale energy storage applications due to its earth abundance, cost-effectiveness and non-toxic nature. Although MnO2 is known as a pseudocapacitive material with superior cycling stability in aqueous electrolytes, its dissolution in non-aqueous electrolytes has restricted its widespread use in long lifetime batteries. In this study, we demonstrate that an ether-based electrolyte solution (1M NaClO4 in diglyme) is able to achieve stable cycling of electrodeposited ε-MnO2 as a cathode for SIBs, reaching a over 75% capacity retention over 1000 cycles. This response surpasses conventional ester-based electrolytes (58% of 1M NaClO4 in EC/PC). A comparative cycling stability study, coupled with electrochemical quartz crystal microbalance characterization, validates the efficacy of the ether-based electrolyte in mitigating MnO2 dissolution. Furthermore, the integration of 3D printed graphene aerogel (3D GA) as a scaffold for electrodeposited MnO2 leads to enhanced electrochemical performance of the MnO2 electrode (3D MnO2/GA), resulting in a high areal capacity of 4.4 mAh cm-2 at a current density of 10 mA cm-2. The 3D MnO2/GA electrode possesses scalable electrochemical performance with mass loadings from 20 mg cm-2 to 80 mg cm-2. Using this electrode, a high mass loaded sodium-ion battery (SIB) device was fabricated by using utilizing 58 mg cm-2 3D MnO2/GA as the cathode and 16 mg cm-2 dip-coated TiO2@Cu foam as the anode. This MnO2 | TiO2 device delivered a notable areal capacity of 6.2 mWh cm-2 and a high areal power density of 70.7 mW cm-2. Moreover, the SIB device demonstrates 85% capacity retention after 500 cycles, underscoring the stable cycling of this high-energy and power-density SIB device.

Spatiotemporal evolution and interaction of water constraints and their socio-ecological drivers in the Taihu Lake Basin

To effectively manage water constraints (WCs) within a basin, it is crucial to first scientifically delineate their spatial distribution and thoroughly understand the interactions between WCs. Investigating the complex driving mechanisms at multiple scales is also essential. In this study, a basin WC evaluation framework is constructed using a conflict risk assessment model. The spatiotemporal variations of four types of WCs across three spatial scales in the Taihu Lake Basin (TLB) are thoroughly investigated. Furthermore, the study quantifies the trade-offs, synergy effects, and bundle patterns of these water constraints. The study employs the Optimal Parameters-based Geographic Detector (OPGD) and multivariate linear regression to identify the key socio-ecological drivers of WCs. Our findings indicate that between 2010 and 2020, water resource constraint (WREC), water environment constraint (WENC), water safety constraint (WSAC), water ecology constraint (WECC), and the comprehensive WC (CWC) displayed varying degrees of heterogeneity. Particularly, the mean values of WSAC, WECC, and CWC witnessed an increase over the decade. Additionally, all WCs exhibited a strong positive spatial autocorrelation. Synergistic interactions among WCs were predominantly observed in pairs such as WREC-WSAC, WREC-WECC, and WSAC-WECC, while a weaker trade-off effect was noted in the WENC-WECC pair. At multiple scales, we identified eight types of WC bundles capable of undergoing mutual transformations, especially at the basin scale. The primary drivers of WCs varied across different stages and scales, with most factors collectively exerting a more significant impact than individually. Notably, factors like secondary and tertiary industry GDP (X2), population density (X3), precipitation (X6), and elevation (X7) were identified as core drivers influencing the evolution of WCs in the TLB. Integrating these spatiotemporal characteristics and driving mechanisms of WC interactions into basin planning and management can significantly support the alleviation of multidimensional water constraints in territorial spaces.

The impact of water resource constraints on industrial linkages in the Yellow River basin

The impact of water resource constraints on industrial linkages in the Yellow River basin

Integrated assessment of crop planting suitability: A case study in the Hetao Irrigation District of China using HJ-1A/1B satellite data

The increasing demand for food due to population growth and climate change poses significant challenges to achieve the Sustainable Development Goal of zero hunger by 2030. A key aspect in overcoming these challenges is to determine appropriate planting patterns for various crops, aimed at enhancing regional-scale crop water productivity despite the constraints of limited water and land resources. Remote sensing data and models provide the possibility for accurately estimating water productivity of different crops on a regional scale, but studies on remote sensing-based assessments of regional crop water productivity and its applications in agricultural management are still limited. In this study, we present a satellite-based integrated approach to assess crop planting suitability based on regional crop water productivity estimation. Focusing on the Hetao Irrigation District (HID) in the upper Yellow River basin, a representative irrigation district in arid region of Northwest China, we first use remote sensing data (HJ-1A/1B) to estimate water productivity for the two major crops, maize and sunflower, within the HID from evapotranspiration and yield estimates. Additionally, we introduce a novel crop planting suitability index based on the frequency distribution of crop water productivity, facilitating the determination of appropriate crop planting patterns. Our findings reveal that Dengkou, the periphery of Hangjinhouqi, and the southern part of Linhe are optimal for maize cultivation, while Wuyuan and the northern part of Linhe are ideal for sunflower cultivation. This is attributed to higher water productivity levels for maize in Dengkou (2.46 kg/m³) and Linhe (2.15 kg/m³), and for sunflower in Wuyuan (0.86 kg/m³). Following the optimization of crop planting distribution, the average water productivity for maize and sunflower increases by 7.6 % and 5.0 %, respectively. The proposed method can be generalized to other regions, and the results offer valuable insights for local governments in decision-making to regulate cropping pattern and maximize regional crop water productivity.

Measurement and evaluation of agricultural technological innovation efficiency in the Yellow River Basin of China under water resource constraints

Improving the efficiency of agricultural technology innovation is an inevitable requirement for ecological protection and sustainable agricultural development in the Yellow River Basin. Under the background of prominent water resources constraints in the Yellow River Basin, the actual level and regional differences of agricultural technology innovation efficiency in the basin are analyzed, which will provide theoretical basis and data reference for the development plan of agricultural modernization in the Yellow River Basin. The construction of evaluation index system and the choice of method are the main factors that affect the measurement results. Therefore, this paper first selects input indicators such as water-saving technology level and output indicators such as total agricultural output value to construct an innovative evaluation index system of agricultural technology innovation efficiency in the Yellow River Basin under the consideration of water resources constraints. Secondly, the three-stage DEA model was used to eliminate the interference of external environmental variables, and the overall and regional agricultural technology innovation efficiency of the Yellow River Basin during 2011–2020 was measured with the data of prefecture-level cities under the constraint of water resources. Finally, from the perspective of the whole and the region, the spatio-temporal dynamic evolution law is analyzed and evaluated. The results show that: on the whole, the agricultural technology innovation efficiency in the Yellow River Basin is good and rising in a wave trend, the adjusted pure technology efficiency increases, while the scale efficiency decreases. From the regional perspective, although there is regional heterogeneity, the overall development trend is good, and the lower Yellow River has the highest efficiency, followed by the upper reaches and the middle reaches. From the perspective of the change law, the spatio-temporal evolution distribution shows a multi-polarization trend, and the different regions in the upper, middle and lower reaches show great differences. Therefore, promoting the innovation of water-saving technology and the integration of agricultural science and technology, promoting the integration of production, study and research, and strengthening the regional linkage mechanism are helpful to improve the competitiveness of agricultural science and technology and achieve sustainable agricultural development in the Yellow River Basin.

Wind Speed and Vegetation Coverage in Turn Dominated Wind Erosion Change With Increasing Aridity in Africa

AbstractWind erosion is one of the main causes of land degradation and desertification. Clarifying the spatiotemporal variations of wind erosion and the dominant factors of its spatial characteristics and the temporal trend will contribute to the establishment of appropriate wind erosion control and management practices, which is essential for combating global land degradation and strengthening ecological protection in drylands. Here, we assessed wind erosion in Africa during 2001–2020 based on the Revised Wind Erosion Equation (RWEQ). We also analyzed the influential factor of spatial characteristics and temporal variation based on machine learning and other methods under different aridity. Results revealed that the average annual wind erosion modulus was 16,672 t/km2/a in Africa during 2001–2020, with hyper‐arid areas and arid areas accounting for more than 90% of the total wind erosion modulus. The spatial characteristics of wind erosion were dominated by natural factors but not anthropogenic activities. Except in hyper‐arid areas, wind speed and vegetation coverage together dominated the spatial characteristics. Wind speed was the dominant factor in wind erosion change, while in arid and semi‐arid areas, the capability of vegetation coverage to affect wind erosion change was comparable to wind speed. It can be concluded that, although revegetation does contribute to the reduction of wind erosion in arid and semi‐arid areas, taking into account water resource constraints and land use conflicts, large plantations can be replaced with windbreaks to increase vegetation coverage while reducing near‐surface wind speed, which improves the sustainability of ecological projects aimed at combating land degradation and desertification.

Long‐Term Monitoring of the Annual Irrigated Cropland Extent in Fragmented and Heterogeneous Arid Landscapes Using Machine Learning and Landsat Imagery

AbstractUnderstanding the long‐term spatiotemporal evolution of irrigated cropland is essential for water resource management, but this knowledge remains elusive in most water‐stressed arid areas. In this study, we introduced an integrated framework for long‐term and field‐scale mapping of annual irrigated cropland in arid and semiarid regions. This framework combines the k‐means algorithm with a semiautomatically trained random forest classifier for initial classification and employs the Bayesian Updating of Land Cover algorithm for subsequent postprocessing. Taking the Heihe River basin in northwestern China as the experimental area, we generated 30‐m annual irrigated cropland maps spanning from 1990 to 2020 based on Landsat imagery and the Google Earth Engine. Comprehensive validation confirmed the reliability of this approach, with the overall accuracy of the annual maps ranging from 83% to 88.3% (mean: 86.6%). Our data set provides an unprecedentedly long‐term and fine‐scale perspective for understanding the continuous spatial and temporal dynamics of irrigated cropland in the Heihe River basin, surpassing previous studies in Central Asia and northwestern China. Notably, a rapid expansion of irrigated areas is occurring in the basin, especially in the water‐stressed midstream and downstream areas. This finding points to potential ecological risks in the foreseeable future due to water resource constraints.

Trends in the future evolution of rural settlements in oasis-desert areas under water use simulation scenarios: Take the Hexi Corridor region of China as an example

The uncontrolled expansion of rural settlements caused by the imbalance in the matching of land and water resources has hindered the realization of the goal of sustainable rural development in the oasis-desert area. In this study, “water resources-land resources-oasis rural settlements” are integrated into the same framework of symbiosis development, and the evolution of rural settlements in the context of water and land resources constraints is predicted. We used the coupled “SD-SOS-FLUS” (“system dynamics-suitable oasis structure-future land use simulation”) model to predict the differences in rural settlement sizes and their spatial distribution under the inertial development water use scenario (ID) and sustainable development water use scenario (SD) in the northeast part of the Hexi Corridor in China. In addition, we explored differences in oasis circle structure and land use structure under different water allocation scenarios. Compared with a single model, the coupled model “SD-SOS-FLUS” can better simulate the symbiosis relationship between “water resources-land resources- oasis rural settlements”. Through the prediction, the proportion of water used for production in the ID scenario is still as high as 86.30 %, while the proportion of ecological water use is only 11.50 %, and the continuous imbalance of the water use structure results in the area of arable land and rural settlements will be increased to 7,473.21 km2 and 487.16 km2. It increased by 115.63 km2 and 41.28 km2 respectively compared to 2020, which in turn made the oasis area expanding outward, and the radius R of the oasis also increased from 53.65 km in 2020 to 54.79 km in 2030. The area of arable land and rural settlements under water and land resource constraints in the SD scenario decreased to 5223.56 km2 and 105.04 km2. The contraction of the oasis increases the transition zone circle width B2 from 19.88 km in 2020 to 24.58 km in 2030, an increase of 5 km compared to the ID scenario. As a result of the spatial reconfiguration, the number of rural settlement patches decreased from 1.04 × 104 to 0.15 × 104 in 2020, saving 3.41 × 104 ha of land after optimization.

Optimization of maize irrigation strategy in Xinjiang, China by AquaCrop based on a four-year study

Global water scarcity has become a non-negligible problem that threatens the sustainable development of agriculture. In order to alleviate the contradiction between grain demand and water resource constraints, it is particularly important to explore appropriate irrigation strategy so as to synergistically increase grain yield and water use efficiency (WUE). The AquaCrop model were locally calibrated to simulate optimal irrigation amount for different hydrological years using a four-year field measurements (from 2017 to 2020) of maize with two irrigation levels (2400 m3/ha and 4800 m3/ha) in Shihezi, Xinjiang, China. On this basis, regulated deficit irrigation (RDI) strategies were optimized based on the variation of water consumption and soil water content (SWC) during the maize growth period. Results suggest that the optimal irrigation amount under static strategy (fixed proportion irrigation in growing season) in the wet, normal, and dry years was 4733 m3/ha, 5381 m3/ha, and 6090 m3/ha, respectively. In dynamic strategies, the optimized RDI4 (65% Ir (the amount of water required for each irrigation interval) at R2-R5 stage) and RDI5 strategy (85% Ir at V6-V12 stage and 85% Ir at R2-R5 stage) can save irrigation water while maintaining high yield. Under the premise of basically maintaining high yield (18Mg/ha), compared with each year's irrigation amount of 4800 m3/ha, the RDI4 strategy can reduce the irrigation amount by 4.33% in 2017; although the irrigation amount was slightly increased by 2.77% under the RDI5 strategy in 2018, the yield could be increased by 3.65%; in 2019, the RDI5 strategy can save 49.44% of irrigation water, and the RDI4 strategy will save 24.13% of irrigation water in 2020. From this study, it is recommended that a single irrigation amount of 65% Ir in R2 to R5 stages of maize growth or 85% Ir in V6 to V12 stages and 85% Ir in R2 to R5 stages can save irrigation water while maintaining high yield (18 Mg/ha).

Research on the Spatiotemporal Characteristics of the Coupling Coordination Relationship of the Energy–Food–Water System in the Xinjiang Subregion

In the Xinjiang region, the sustainable management of water resources, energy, and food is crucial for regional development. This study establishes a coupling evaluation index for energy–food–water (EFW) systems from the perspectives of supply, consumption, and efficiency. Using an integrated EFM-CDD-RDD-CCDM approach, an assessment of the coupling and coordination levels of the EFW systems in 14 cities within Xinjiang was conducted for the period of 2004 to 2020. Additionally, the method of obstacle degree identification was utilized to determine the main barriers affecting the EFW systems. Key findings included the following. (1) In terms of individual system coordination indices, the water resource systems exhibited overall higher coordination (ranging from 0.30 to 0.72) with comparatively minor spatial variability, while the energy (from 0.18 to 0.81) and food (from 0.12 to 0.83) systems showed greater temporal and spatial fluctuations. From 2004 to 2020, improvements were observed in the coordination of food and water resource systems, whereas a decline was noted in the coordination of the energy subsystem. (2) Prior to 2011, the coupling of food–water and energy–food systems showed an upward trend, whereas the energy–water coupling decreased annually by 2.62%, further highlighting the tensions between energy development and water resource constraints in Xinjiang. (3) The comprehensive coupling coordination index of the Xinjiang EFW systems ranged between 0.59 and 0.80; between 2004 and 2020, there was an oscillatory increase. From 2004 to 2016, the coupling and coordination degree across the municipalities generally improved, with the regions on the western side and southern slope of the Tianshan Mountains, the Altai Mountains, and the northwestern edge of the Junggar Basin exhibiting the highest levels, followed by the three prefectures in southern Xinjiang. (4) The EFW obstacle degree posed by the food systems in Xinjiang and its divisions showed a decreasing trend from 2004 to 2020, with the energy system identified as the main factor affecting the coupling and coordination degrees of the EFW systems (increasing by 44% to 52%). Therefore, it is imperative to accelerate the energy transition and optimization in the lead energy development and production areas of Xinjiang. This research provides a scientific basis for Xinjiang’s sustainable development strategies and highlights potential directions for the future optimization of resource management.

Is water replenishment an effective way to improve lake water quality? Case study in Lake Ulansuhai, China

Lakes are an important component of the global water cycle and aquatic ecosystem. Lake water quality improvement have always been a hot topic of concern both domestically and internationally. Noncompliant outflow water quality frequently occurs, especially for lakes that rely mainly on irrigation return flow as their water source. External water replenishment to improve the water quality of lakes is gradually being recognized as a promising method, which however, is also a controversial method. Lake managers, in the case of constant controversy, hesitate about the appropriateness of lake water replenishing. Thus, taking Lake Ulansuhai in China as an example, this study aimed to construct a lake hydrodynamic and water quality model, under the constraint of multiple boundary conditions, that has sufficient simulation accuracy, and to simulate and analyze the changes in COD (Chemical Oxygen Demand) and TN (Total Nitrogen) concentrations in the lake area before and after water replenishment, and explore whether water replenishment was an effective method for improving lake water quality. The results showed that when the roughness value of Lake Ulansuhai was 0.02, the TN degradation coefficient K was 0.005/d, and the COD degradation coefficient K was 0.01/d; the simulation and measured values had the best fit, and the built model is reasonable and reliable can be used to simulate lake water quality changes. By external water replenishment lasting 140 days in the water volume of 4.925 × 108 m³, the COD and TN concentrations in Lake Ulansuhai could be stabilized at the Class V water quality requirement, which helped improve the self-purification ability of the lake area. Water replenishment was proved to be an effective method for improving the water quality of the lake, but water replenishment is only an emergency measure. Lake water replenishment is more applicable to areas with abundant water resources. External source control and internal source reduction of lake pollution and protection of lake water ecology are the main ways to improve lake water quality for water-deficient areas under the rigid constraints of water resources. In the future, key technologies for reducing and controlling pollution in irrigation areas, construction of lake digital twin platforms, and active promotion of lake legislation work should be the main research direction for managing the lake water environment.

Framework of land use planning for an energy producing city of Northwest China based on water-energy-food nexus

The development of cities and their industries is constrained by the water-energy-food nexus (WEF nexus) formed under certain biophysical conditions. Urban-scale WEF nexus research is very different from macroscale (global or national) research. There is a need for quantitative optimization of several economic sectors, as well as spatial heterogeneity of resource endowments, to develop policies that are distinctive for different levels of endowments. Currently, China is implementing Territorial Spatial Planning (TSP) at all administrative levels throughout the country. Its theoretical basis is to realize the overall management of urban ecological protection land, urban expansion, and industrial growth by measuring the resource carrying capacity and land development suitability of each plot. This provides an opportunity to explore the interconnections between WEF nexus at urban scale by examining the wide range of urban resource availability. Here, we propose the WEF-TSP framework, which helps to realize the multi-objective development needs of regional ecological protection, urban expansion, agricultural development, and energy production in a certain city and provides a decision-making basis for future urban land spatial planning. Ordos, a city in China recognized for its significant energy reserves, has been selected as the subject of a case study. Combined with the spatial heterogeneity of Ordos's resource endowment and focusing on the strong constraints of water resources and ecological protection, this study explores the urban land spatial layout scheme of Ordos in 2030 under different energy development scenarios. It can also provide a reference for other cities in China and even the world to study the spatial layout of urban land use and industrial development based on the WEF nexus.

Estimation of ecosystem water consumption and the suitable scale of cultivated land in the Karamay region and Muzat River basin based on the optimized SEBAL energy balance model and water resource constraint model

Food security is closely related to the development of human society, and the root of food production lies in cultivated land, with water conservancy as its lifeline. This study estimates the ecological water consumption of located in the arid region of Northwest China (the Karamay region and Muzat River basin) from 1990 to 2020 based on the optimized Land Surface Energy Balance Algorithm. The verification accuracy of SEBAL energy balance model is greatly improved after optimization. It was showed an increasing trend in the Karamay region and Muzat River basin, increasing at the rates of 2.84 mm/year and 2.86 mm/year respectively. The suitability of cultivated land was evaluated by combining four periods of 30 m spatial resolution land use/land cover data from 1990, 2000, 2010, and 2020, as well as the Hydrological Statistical Yearbook and Xinjiang Statistical Yearbook. Through the analysis of spatial optimization for cultivated land, it can be inferred that the primary limiting factors affecting cultivated land suitability in the Karamay region are irrigation guarantee rate (54.03%) and soil salinity (11.98%). Muzat River region are irrigation guarantee rate (32.19%) and soil salinity (18.62%). By comparing the scenarios of setting ecological priority and cultivated land priority, it is concluded that under the conditions of water resource constraints and 50%, 75% and 90% design irrigation assurance rates, Karamay still has cultivated land expansion potential, which can be used as the main preparatory reclamation area. In addition to the traditional agriculture irrigation area, the Muzat River basin still has development potential under the condition of ecological priority and no more than 75% irrigation design assurance rate. The study on the cultivated land suitability under the condition of water resource constraints can provide new ideas for food security.

Floating Solar Panel on Agriculture Pond

Floating solar power plants present an innovative solution for farmers facing constraints of limited land and water resources. This study assesses the feasibility of on-grid floating solar power plants for farmers, offering a sustainable and cost-effective energy source while conserving land area and improving water quality. Through technical, economic, and environmental analyses, this study demonstrates the viability of on-grid floating solar power plants, highlighting their potential to enhance farmers' livelihoods and contribute to rural sustainable development. Additionally, this paper introduces a novel approach by estimating the technical potential of floating photovoltaic systems (FPV) at the province/municipality level, focusing on water irrigation ponds, thus offering insights for localized implementation strategies.

Optimization of Forest and Grass Vegetation Distribution in the Aksu River Basin by Water Resources Carrying Capacity

In arid areas, vegetation is the basis for maintaining the virtuous cycle of ecosystems, while water resources are the key factor restricting the survival of vegetation communities. The balance between water resources and vegetation is related to the sustainable development of ecological benefits and economic benefits in arid areas. Although research on the carrying potential of vegetation in arid areas has been emphasized, there is still a lack of spatial analysis of different vegetation types over large areas. Therefore, this study takes precipitation as the basic source of water resources, calculates the amount of available water resources in the basin from the available effective precipitation and available irrigation water, and it analyzes the spatial distribution of forest and grass vegetation types under the water resources constraint, combined with the ecological water demand of different vegetation types and based on the principle of “Water to determine the Vegetation”. The results showed that the ecological water demand of each vegetation type was as follows: Forest > Shrub Vegetation > Grassland Vegetation > Desert Vegetation. The range of comprehensive available water resources of vegetation was from 0 to 221.71 mm, which decreased with the altitude gradient. Then, the spatial distribution pattern of vegetation types constrained by the water resources in the Aksu River Basin showed a striped distribution from north to south, with shrub vegetation in the high-altitude mountainous area, grassland vegetation in the low-altitude area, and desert vegetation in the desert plain area, respectively, accounting for 29.05%, 10.74%, and 53.45% of the total basin. This research approach provides a scientific basis for the planning of forest and grass vegetation construction in arid regions.