Agricultural Water Consumption Research Articles

Distortion and Improvement Method of Location Quotient in Water Consumption Evaluation

Location quotient (LQ) is a widely used model to evaluate the spatial aggregation of water consumption. The conventional view is that all the domains of the LQ values in different water-using departments are [0, +∞). The larger the LQ is, the higher the degree of water consumption concentration is. With the water consumption structure evaluation of Northwest China as an illustration, this study shows the following: (i) The conventional LQ has a distortion phenomenon. The agricultural water consumption of Xinjiang Province accounts for more than 70.4% of the total water consumption in the whole study area, indicating that this department plays a dominant role. However, its conventional LQ is only 1.06, which is much less than the conventional LQs of the industrial and domestic water consumptions of Gansu Province and Shaanxi Province. (ii) The mathematical essence of this distortion in the conventional LQ model is that the conventional view that all the domains of the LQ values in different water-using departments are [0,+∞) is not tenable. The actual domain of the i-th department in the j-th province is [dij, dij−1], where dij is the water consumption proportion of this department accounting for the whole study area. For the department with high water consumption, the upper limit of its LQ is too small. Thus, the conventional LQ values of different water-using departments are not directly comparable. (iii) An improved LQ model is designed by introducing the standardization procedure. The improved LQ values of different water-using departments are [0, L], making them directly comparable. The improved LQ of the agriculture department in Xinjiang Province is 1.56, which is the most significant of all. This finding indicates that the water consumption in Northwest China is significantly concentrated in the agriculture department in Xinjiang. The evaluation results of the improved LQ model are more realistic and more suitable for the government’s water resources management than those of the conventional model.

Assessment of Economic Efficiency of Water Use through a Household Farmer Survey in North China

Water use efficiency (WUE) is one of the most widely used indicators in agricultural water management. Although this indicator has obvious advantages, it is limited to measuring the relationship between crop yield and corresponding water use. In recent years, many researchers have noted that understanding the economic efficiency of water use (EEWU) could have great water-saving potential, while it has been poorly investigated with respect to China’s agricultural water management. This paper assesses EEWU through a household farmer-level survey in the piedmont region of North China. First, EEWU of crops are estimated based on agricultural water consumption (including irrigation water and effective precipitation) and profit (including gross profit and net profit); Second, the impact of monthly price changes in 2019 and annual price changes in 2014–2019 on EEWU is analysed. Main conclusions are as follows: (1) EEWU values of cash crops such as apple and cauliflower are much higher than those of grain crops such as wheat and maize; (2) For different crops, the median economic efficiency of irrigation water (EEWiU) and total water (EEWtU) range from 31.71 to 99.54 ¥/m3 and 11.31 to 44.05 ¥/m3, respectively; (3) The multi-year average EEWiU and EEWtU ranged from 4.75 to 63.99 ¥/m3 and from 2.67 to 31.71 ¥/m3, respectively. Economic efficiency of water use shows a slightly downward trend in the period of study, which would contradict the trend towards the use of more water-efficient technologies and shows an even larger margin of improvement in the domain of agricultural water efficiency. The results provide a powerful reference for the management of agricultural water use through economic leverage.

Coupling reconstruction of atmospheric hydrological profile and dry-up risk prediction in a typical lake basin in arid area of China

Arid area is very sensitive to global warming and are extremely vulnerable to climate change. Moreover, the water resources system in the arid area is fragile and will undergo tremendous changes with climate change. Therefore, the interaction of climate and hydrology in arid area has an important impact on the formation of regional microclimate and hydrological changes. Daihai Lake is a typical closed inland lake in arid area of China, and a key area for ecological protection in North China. In this paper, WRF-Hydro model is used to simulate the climate hydrological coupling situation of Daihai Basin from 1980 to 2020, and the coupling results are verified and calibrated by meteorological statistics, runoff calculation and remote sensing analysis. Based on the synopsis of climate and hydrology in the past 40 years, the causes and future trends of the hydrological elements in Daihai Basin are analyzed. Through the analysis, it is found that the interannual variation of precipitation in Daihai Basin is sharp, with 401.75 mm as the average from 1980 to 1994; and drastic fluctuations from 1995 to 2011, with a difference of nearly 400 mm between the interannual maximum and minimum; From 2012 to 2020, the fluctuation is small. Although the interannual variation of evaporation fluctuated, it showed an upward trend with a slope of 8.855 mm/year. The annual average temperature showed an obvious upward trend with a slope of 0.040 °C/year. From 1980 to 2020, the inflow of Daihai Lake shows a downward trend; Since 2013, the runoff into the lake has tended to be flat. Climate change and human activities are the decisive factors leading to the change of water quantity in Daihai, among which human activities play a greater role. Cultivated land irrigation and industrial water use are highly correlated with the lake discharge, and these two factors have a great influence on the lake discharge. If the current agricultural and industrial water consumption does not increase, Daihai still has a lifespan of nearly 120 years. If human activities do not change and any protective measures are not taken in time, under the background of global climate change, the flow of the Daihai Lake into the lake will be reduced to zero in 2025, and the Daihai Lake will completely dry up in 2031–2033. The study of climate hydrological coupling of long time series in Daihai Basin can not only make up for the lack of runoff data, but also provide the basis for water resources management, disaster prevention and mitigation.

Spatiotemporal Distribution of Irrigation Water Use Efficiency from the Perspective of Water Footprints in Heilongjiang Province

Water footprints can reflect the sources and utilities of water resources. Introducing the water footprint theory to evaluate irrigation water use efficiency can reflect agricultural water consumption more scientifically and accurately. This study analyzes the variation trends of the blue, green and gray water footprints of grains in different regions of Heilongjiang Province and selects the grain-sowing area, total agricultural machinery power, grain blue water footprint and green water footprints and absolute fertilizer amount as input indexes and the agricultural gross product and gray water footprint of grain as output indexes. A slacks-based measure–data envelopment analysis (SBM-DEA) model is used to estimate the irrigation water use efficiencies of 11 cities in Heilongjiang Province, analyze the corresponding spatiotemporal distribution and further decompose and calculate the irrigation water use efficiencies of the five economically underdeveloped second-level cities. The results suggest that the spatial distribution of the grain water footprint in Heilongjiang Province reflects coexisting areas of excess and scarcity. The irrigation water use efficiency showed a steady and slow downward trend from 2008 to 2018. The irrigation water use efficiency reflected significant spatial differences in Heilongjiang Province, with a pattern of high values in the southwest and low values in the northeast; these differences have gradually narrowed. The average irrigation water use efficiency in Heilongjiang Province was 0.821 and the irrigation water efficiencies of Harbin, Qiqihar and Jixi were at the forefront of the province. Jiamusi, Hegang, Shuangyashan, Yichun, and Mudanjiang are the five cities with below-provincial-average irrigation water use efficiencies. The irrigation water use efficiency of Heilongjiang Province mainly depends on the pure technical efficiency. In the future, technical inputs should be improved on the basis of optimizing the agricultural production layout, focusing on improving the pure technical efficiency. The research results obtained herein can provide a theoretical basis for agricultural water management in Heilongjiang Province.

Multi-dimensional evaluation of water footprint and implication for crop production: A case study in Hetao Irrigation District, China

Developing water-saving agriculture must balance the interests of stakeholders in terms of economic benefits, food and ecological security objectives. The production-based water footprint (PWF), the energy-based water footprint (EWF), and the net benefits-based water footprint (NBWF) (including grey water footprint (GWF)) can be used to evaluate food and ecological security, water use efficiency, and benefits objectives. However, little attention is paid to the multi-dimensional evaluation of water consumption in agriculture. This study quantified the annual PWF, EWF, and NBWF of grain crops, cash crops, and feed crops in the Hetao Irrigation District (HID) over 1995–2017, and analyzed their spatiotemporal evolution characteristics and comparative advantages, then clarified the implications of the three types of water footprints for stakeholders in the HID for crop planning. The results showed the water use efficiency was decreasing and the benefits were increasing. The GWF deserves more attention as it contributed 35%− 40% of the total water footprint. The comparative advantages of the three water footprints revealed that the current crop distribution in the HID only favors benefits. Considering the crop distribution issues in the HID, the adjustment objectives can be determined by combining the connotations of the three types of water footprints, GWF, PWFblue-green/EWFblue-green, and NBWFblue-green, corresponding to stakeholders’ environmental and social-economic interests. This study could provide basic guidance for crop planning and agricultural water management in the HID and similar areas.

Remote Sensing-Based Agricultural Water Accounting for the North Jordan Valley

Remote sensing can provide important and updated information for agricultural water accounting (AWA). In this study, data from the open-access portal (WaPOR) of the Food and Agricultural Organization was used in AWA to assess levels of agricultural water consumption and to provide possible solutions for water deficiency in the North Jordan Valley (NJV). Consolidated procedures have been applied to complement and validate the WaPOR products. These included the use of climatic and ground data, the multispectral remote-sensing data of Sentinel-2 and Landsat 8 to derive land use/cover maps, GIS layers, and calibrated evapotranspiration (ET) estimates using the surface energy balance algorithm for land (SEBAL). The data of water inflows and outflows were analyzed using the water accounting plus (WA+) system. Results showed that the WaPOR data of actual ET and interception (AETI) were highly correlated with SEBAL-ET, with WaPOR data overestimating ET for irrigated areas. Precipitation data from WaPOR, on the other hand, were underestimating inflow from rainfall, although significant correlations were observed between these data and rainfall records. As a result, the quality of WaPOR data affected the outputs from agricultural water accounting. The main impact on water accounting outputs was the underestimation of percolated water that could be utilized as a possible solution to water deficiency in the NJV. In addition, the water accounting performance indicators were relatively affected, although they reflected the nature of the study area where water deficiency predominated as a result of inter-basin transfer. The study compared outputs from water accounting in terms of the possible solutions to water deficiency in the NJV and concluded that considerable amounts of recoverable water could be developed when compared with the option of developing surface water from the side wadis. Also, it emphasized the important role of remote-sensing sources for providing information for AWA needed for improved water management and governance.

Assessing agro-environmental sustainability of intensive agricultural systems

Sustainable production in water-scarce regions entails not to overshoot the sustainable blue water availability (BWA), which in turn requires addressing environmental flow requirements (EFRs). We explored the long-term effects of agricultural development, before (1984–1997) and during (1998–2018) the operation of the modern irrigation and drainage network of Tajan (TIDN), northern Iran, on the sustainability of blue water consumptions. A combination of different methods were applied to estimate hydrological EFRs of rivers, ab-bandans (traditional water reservoirs), and groundwater resources. Three major pollutants in the region's water resources, including nitrogen, phosphorus, and salinity, were used to estimate water quality EFR. Monthly agriculture water footprints (WFs) were calculated using the AquaCrop model, and then were compared with the region's BWA, which was calculated by subtracting monthly EFRs from monthly natural runoff. When WF exceeded BWA, the production system includes unsustainable water consumption. The EFR satisfaction of surface water decreased after TIDN operation by about 19%. Unmanaged nitrogen application and post-TIDN overexploitation of groundwater resulted in substantial increase in groundwater EFR violation. The TIDN led to more water consuming cropping pattern resulting in increased agricultural water consumption by about 73%. Overall, agricultural development in TIDN was beyond the capacity of the area, which resulted in up to about 167 MCM y−1 unsustainable blue water consumption. Based on the results, the new framework presented for assessing agro-environmental sustainability could assist managers and policy makers to modify agricultural systems according to environment resilience.

Study on the Matching Method of Agricultural Water and Land Resources from the Perspective of Total Water Footprint

The matching status of agricultural water and land resources is a prerequisite for grain production. The influence of gray water footprint has not been paid attention to in the study of agricultural water and land resources matching based on water footprint. To measure the matching status of agricultural water and land resources more comprehensively, the total water footprint (including blue, green and gray water footprint) and the cultivated land area was taken as the characterization parameters of water and land resources, respectively. The Gini coefficient model, and the agricultural water and land resources matching coefficient model were constructed to calculate the matching degree of agricultural water and land resources in a cold region (Heilongjiang Province) of China. Based on the amount of agricultural water consumption, the equivalent coefficient model was used to evaluate the degree of agricultural water and land resources shortage or to be developed. The result of agricultural water and land resources matching coefficient model showed that the matching degree of agricultural water and land resources in Heilongjiang Province is getting better year by year, which is consistent with the calculations determined from the Gini coefficient. The result of the equivalent coefficient method based on agricultural water consumption was consistent with the result of the Gini coefficient method based on total water footprint, which is verified that it is scientific and reasonable to take the total water footprint as the characterization parameter of water resource. The findings may provide implications for the spatial optimal allocation of regional agricultural water and land resources.

Energy-Water Consumption and Food Yield: An Empirical Dual Sectors Dynamic Equilibrium Model

ABSTRACT This paper develops a dual sectors dynamic equilibrium model and introduces agricultural energy consumption and agricultural water consumption in a growth model that tested by using a panel data set from 2004 to 2016 in China. It presents a theoretical prediction on the interactions between agricultural energy consumption, agricultural water consumption, and food yield. Consistent with this prediction, agricultural electricity consumption and agricultural water consumption by themselves appear to have significant effects on food yield. The fixed-effects models verify that agricultural electricity consumption, agricultural water consumption, and food yield have long-run equilibrium relationships. The results of weather-based robustness checks reveal that food yield is positively correlated with agricultural electricity consumption. Also consistent with theory, agricultural water consumption is positively associated with food yield. These results are generally stable and hold with tests of panel data unit roots, with alternative estimation strategies, and with or without controlling for covariates.

Differential Bioaccumulation Patterns of α, β-Hexachlorobenzene and Dicofol in Adipose Tissue from the GraMo Cohort (Southern Spain)

To identify bioaccumulation patterns of α-, β- hexachlorocyclohexane (HCH) and dicofol in relation to sociodemographic, dietary, and lifestyle factors, adipose tissue samples of 387 subjects from GraMo cohort in Southern Spain were analyzed. Potential predictors of these organochlorine pesticides (OCP) levels were collected by face-to-face interviews and assessed by multivariable linear and logistic regression. OCPs were detected in 84.2% (β-HCH), 21.7% (α-HCH), and 19.6% (dicofol) of the population. β-HCH levels were positively related to age, body mass index (BMI), mother’s occupation in agriculture during pregnancy, living in Poniente and Alpujarras, white fish, milk and water consumption, and negatively related to being male, living near to an agricultural area, working ≥10 years in agriculture, and beer consumption. Detectable α-HCH levels were positively related to age, BMI, milk consumption, mother’s occupation in agriculture during pregnancy, and negatively with residence in Poniente and Alpujarras, Granada city, and Granada Metropolitan Area. Residence near to an agricultural area, smoking habit, white fish and water consumption, and living in Poniente and Alpujarras, Granada city and Granada Metropolitan Area were negatively associated with detectable dicofol levels. Our study revealed different bioaccumulation patterns of α, β-HCH and dicofol, probably due to their dissimilar period of use, and emphasize the need for assessing the exposure to frequently overlooked pollutants.

Groundwater storage change and driving factor analysis in north china using independent component decomposition

North China (NC) is faced groundwater shortage in the past decades. To understand the characteristics of Groundwater Storage (GWS) change in NC, GWS Anomaly (GWSA) is analyzed by using Independent Component Analysis (ICA) with the high-resolution time-variable gravity field model Tongji-RegGrace2019 and hydrological models. According to the spatiotemporal characteristics of Independent Components (ICs), the driving factors and corresponding driving mechanism of GWS changes are further investigated. Results show that the GWS in NC is decreased with a rate of −0.87 ± 0.04 cm/yr from January 2004 to December 2015 and the rate increased to −3.71 ± 0.49 cm/yr from January 2014 to December 2015. Among the first four ICs of GWSA, the first and second ICs (IC1 and IC2) cooperatively reflect long-term and intra-annual GWS changes caused by water consumption of coal mining and agricultural irrigation in northern and southern Shanxi province, with the correlation coefficients of −0.91 and −0.85, respectively. IC3 indicates the signal of semi-annual GWS change related to agricultural irrigation water consumption in southern Hebei province, with a correlation coefficient of −0.85. Besides, IC4 suggests the effect of monsoon precipitation and evaporation in front of Taihang Mountain. Hence, the driving factors, including uneven spatiotemporal distribution of precipitation, intense seasonal evaporation, severe loss by coal mining, coupled with exhaustive exploitation for irrigation, jointly restrict the GWS rise and fall at different time nodes.

Quantitative Evaluation and Diagnosis of Water Resources Carrying Capacity (WRCC) Based on Dynamic Difference Degree Coefficient in the Yellow River Irrigation District

In order to effectively deal with the uncertainty between evaluation samples and evaluation criteria, and quantitatively identify the water resources carrying capacity (WRCC) and its obstacle factors in the Yellow River irrigation district, a calculation method of dynamic difference degree coefficient varying with evaluation sample was proposed, and then an evaluation and diagnosis model of WRCC was established. The results applied to the Dagong irrigation district showed that the overall WRCC of five counties in the irrigation district were improved from 2010 to 2017, especially since 2013. The improvement magnitudes of Changyuan County, Fengqiu County, and Hua County were significantly higher than those of Xun County and Neihuang County. In 2017, Fengqiu County, Changyuan County, Hua County, Xun County, and Neihuang County were in water resources critical overloaded status, and the connection number values were 0.231, 0.163, 0.120, −0.293, and −0.331, respectively, which is consistent with the fact that their distances become farther from the main stream of the Yellow River. In addition, the utilization ratio of water resources, available water resources amount per capita, GDP per capita, and water deficient ratio in each county belonged to the middle or strong obstacle index over a long period of time. They were the crucial obstacle factors of WRCC in the Dagong irrigation district, as well as the core and difficult points of water resources management. In some counties, the effective irrigation area ratio, effective utilization coefficient of irrigation water, and water consumption ratio of the ecological environment gradually developed from strong obstacle to weak or strong promotion index. These were important reasons for the improvement of their carrying situation, reflecting their control of agricultural and ecological water consumption. In short, the results of the case study suggest that the model established in this study is conducive to the identification of water resources’ carrying status and its key obstacle factors in the Yellow River irrigation district, and can be applied to the evaluation and regulation of resources and environment carrying capacity.

Deep learning for proximal soil sensor development towards smart irrigation

Excessive agricultural water consumption threatens safe access of billions of people to potable water. Smart irrigation systems offer more efficient water use in irrigated agriculture. Determining irrigation requirements of various soil texture classes in production fields requires more sophisticated sensing technologies such as deep learning. This study has proposed a proximal sensing system by means of using a color camera towards smart irrigation based on computer vision and deep learning to identify water requirements of three soil texture classes under different illumination conditions. An imaging station was composed to reduce the workload in obtaining training images required for training deep convolutional neural network models. Five deep learning architectures were employed to identify texture-water classes: AlexNet, GoogleNet, ResNet, VGG16, and SqueezeNet. Those models were experimented with and investigated to determine the best models in terms of detection performance and speed. By using cross-validation rules, approximately 12,214 images were studied individually for the purpose of training and testing. The AlexNet model outperformed the other deep learning models with an F1-score of 0.9973 in identifying twelve soil texture-water classes. GoogleNet and ResNet displayed the fastest detection speeds with an average processing time of 16.92 ms. The findings obtained from this study have indicated that deep learning bears a great potential in determining irrigation requirements of production fields under varying conditions

Modeling agricultural water-saving compensation policy: An ABM approach and application

With the increasing conflict between water availability and demand on a global scale, regulating water user behavior from the bottom-up perspective has gained attention from both water managers and researchers. This paper presents an agent-based model (ABM) to simulate the farmer behavior under changing physical and institutional environments in a case study of Miyun Reservoir watershed, China. The ABM model simulates the complex adaptive systems of agricultural water users under an agricultural water-saving compensation policy. The model we developed in this study characterizes agents' sensitivity, learning capability, and information radius, which impacts agricultural income and water consumption of a household. By applying this model to a local ‘paddy to dryland’ subsidy policy program aiming at reshaping the agricultural water-saving behavior, the results show that this policy program reduces agricultural water consumption while also reducing household agricultural income. The policy depends on administrative intervention and financial subsidies at first to ensure compliance and gradually shape household behavior in the long run. And we also propose a suitable subsidy range of 250–350 yuan for this policy program in the long run. The model we built can help to understand agricultural water use adaptation to both anthropogenic and environmental interventions. This research also contributes to the coupled natural and human systems study with the bottom-up agent-based model, and the empirical case study provides solid policy implications for the agricultural water use allocation and adaptative management at the watershed scale.

A calculation model for determining the agricultural crops water consumption for resource-saving irrigation regimes

Scientific and technical progress in the development of land reclamation substantiates the urgent need in implementation of a new methodological approach for developing and implementing the processes for resource-saving water use in general, including irrigation of agricultural crops. The essence of the method is that all above-mentioned processes should be substantiated with the ecological-landscape approach methodology, taking into account progressive knowledge both in the accompanying natural sciences and in the reclamation industry that ensures minimal anthropogenic loads on the environment components and the creation of a healthy environmental situation in agricultural landscapes. Empirical dependences of various crops evapotranspiration and the actual moisture supply of the soil root layer have been determined for the corresponding phases of plant development by long-term experimental studies on the irrigation systems of the North Caucasus region for various soil and climatic irrigation zones, followed by comparison of the data obtained with the potential evapotranspiration data at the corresponding meteorological stations. Data analysis shows that the calculated absolute data values of the correlation coefficients between the compared values of the studied parameters vary in a wide range from 0.34 to 0.98, and obtained empirical dependencies are generally described by nonlinear mathematical equations. Comparison between the methods for determining the parameters under study has shown that calculation according to Alpatev gives significant errors; calculation according Kharchenko, while generally satisfactory, allows for unacceptable deviations in particular solutions; calculation according to the proposed model shows good results with acceptable deviations in all cases.

Review of agricultural water-saving policies and measures in recent years – a case study of Jiangsu Province, China

Abstract The scarcity of water resources has posed serious threats to the sustainable development of agriculture. China is a largely agricultural country with a large population, and agricultural water consumption accounts for more than 50% of the total water consumption. The application of water-saving irrigation is the main way to realize the sustainable development of water resources and economics. To comprehensively improve crop water-use efficiency and reduce agricultural water consumption, the Chinese central government have promulgated a series of agricultural water-saving policies since 2012, such as strengthening water management, increasing financial investment, and strengthening project construction and operation management and protection. Taking Jiangsu as an example, this paper reviews the main water-saving policies and measures of governments after 2012, as well as the conflicting interest between different water-saving participants. Results showed that, through water-saving policies and measures, its effective utilization coefficient of agricultural irrigation water (EUCAIW) has increased from 0.59 in 2014 to 0.614 in 2019. By 2019, the area of irrigated arable land controlled by water-saving technologies is 2.848 million hectares, accounting for 67.8% of the irrigated arable land area in Jiangsu. Jiangsu's water-saving policies have been implemented well, and it has guidance on water-saving reform work in other places.

Spatiotemporal changes in water consumption structure of the Yellow River Basin, China

Analyzing and summarizing the evolution law of water consumption structure and proposing corresponding control countermeasures are important for realizing the coordinated development of a regional social economy. In this study, Information entropy, Lorentz curve, Gini coefficient, and Mann-Kendall (MK) trend test were conducted to reveal the spatiotemporal variations in water use characteristics in the Yellow River Basin of China. The results showed a reduction of the dominant position of the single water consumption structure in the basin during 1998–2017, which eventually increased the equilibrium degree among water consumption sectors and made the water consumption structure more reasonable and diversified. The study identified three periods of water consumption structure transformation: 1998 to 2002 as the first growth period, and 2003 to 2012 as the adjustment period, 2013 to 2017 as the second growth period. The spatial distribution was found highly even for agricultural water consumption, while less even for industrial, domestic and ecological water use. The water consumption in agriculture was much higher compared to other sectors. The study can serve as the basis for the optimal utilization of water resources.

Optical Sensor System for Early Warning of Inflow Organic Matter Breach in Large-Scale Irrigation Systems and Water Treatment Systems

A growing world population together with a decrease in water resources have resulted in a deficit in water sources for agriculture. Nations with limited water resources are already using recycled treated water as a vital water source for irrigation. In 2019, treated wastewater made up 45% of the overall agricultural water consumption in Israel. Since recycling systems work continuously and are directly connected to irrigation reservoirs, there is a constant risk of irrigation system malfunctions in the treatment process. In cases of fecal origin, this may result in pathogens entering the irrigation water, the soil, and eventually the food chain. Early warning systems for biological water contamination are important in large-scale processing, yet less studied. This work proposes such a system, with a functional prototype for irrigation-water monitoring by measuring fluorescence spectra in the range of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$300-520 \textit {nm}$ </tex-math></inline-formula> at excitation wavelengths of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$280 \textit {nm}$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$340 \textit {nm}$ </tex-math></inline-formula> , to capture both tryptophan-like fluorescence and humic-like fluorescence. The prototype was successfully tested under simulated field conditions with treated irrigation water as the base substance, and milk injections to simulate dissolved organic matter breaches. Near real-time operation enabled recording biological and chemical dynamics within the substance for the sake of monitoring drift in process control.

Comparison of Crop Evapotranspiration and Water Productivity of Typical Delta Irrigation Areas in Aral Sea Basin

The intensity of agricultural activities and the characteristics of water consumption affect the hydrological processes of inland river basins in Central Asia. The crop water requirements and water productivity are different between the Amu Darya and Syr Darya river basins due to the different water resource development and utilization policies of Uzbekistan and Kazakhstan, which have resulted in more severe agricultural water consumption of the Amu Darya delta than the Syr Darya delta, and the differences in the surface runoff are injected into the Aral Sea. To reveal the difference in water resource dissipation, water productivity, and its influencing factors between the two basins, this study selected the irrigation areas of Amu Darya delta (IAAD) and Syr Darya delta (IASD) as typical examples; the actual evapotranspiration (ETa) was retrieved by using the modified surface energy balance algorithm for land model (SEBAL) based on high spatial resolution Landsat images from 2000 to 2020. Land use and cover change (LUCC) and streamflow data were obtained to analyze the reasons for the spatio-temporal heterogeneity of regional ETa. The water productivity of typical crops in two irrigation areas was compared and combined with statistical data. The results indicate that: (1) the ETa simulated by the SEBAL model matched the crop evapotranspiration (ETc) calculated by the Penman–Monteith method and ground-measured data well, with all the correlation coefficients higher than 0.7. (2) In IAAD, the average ETa was 1150 mm, and the ETa had shown a decreasing trend; for the IASD, the average ETa was 800 mm. The ETa showed an increasing trend with low stability due to a large amount of developable cultivated land. The change of cultivated land dominated the spatio-temporal characteristics of ETa in the two irrigation areas (3). Combined with high spatial resolution ETa inversion results, the water productivity of cotton and rice in IAAD was significantly lower than in IASD, and wheat was not significantly different, but all were far lower than the international average. This study can provide useful information for agricultural water management in the Aral Sea region.

黄河流域可持续发展评估及协同发展策略

作为我国重要的生态屏障和经济带，黄河流域生态保护和高质量发展是我国的重大战略需求。目前，黄河流域水资源利用效率较低、水资源配置不甚合理等问题，阻碍了流域整体的可持续发展。以黄河流域上、中、下游9个省份作为研究对象，引入目标间均衡度这一新的评估方法，通过分析上中下游在可持续发展目标达成状况、发展路径、对黄河水资源的依赖程度和工农业用水效率等方面的差异，探讨了基于水资源优化利用的协同发展策略。研究结果表明：（1）2000-2015年间，黄河九省的可持续发展指数都有了显著提高，在不考虑各可持续发展目标间的均衡度时，中下游地区的可持续发展状况显著优于上游地区，考虑均衡度后则未发现显著差异；（2）忽略均衡度对评估结果带来的偏差也体现在省级层面上，如宁夏和山西在不考虑均衡度时都被认为取得了良好的发展，但实际上两者的发展主要体现在少部分目标上，和环境保护相关的部分目标反而出现了退步，这说明不考虑均衡度可能会高估可持续发展目标达成度；（3）黄河流域上中下游均有对黄河水资源较为依赖的省份，这些省份间工农业用水量和用水效率等存在较大差异，总体来看，上游地区用水效率较低，中下游地区用水效率较高；（4）取水量与17个可持续发展目标间的关系在上中下游有所差异，在上游地区取水量同多数目标无关或呈负相关关系，说明限制上游地区可持续发展的因素不是水资源，而在中下游地区取水量的增加则能够促进一些同经济和社会发展相关的目标。可以通过加强上、中、下游间的合作，优化产业结构和水资源配置，提高流域整体的水资源利用效率，促进流域生态环境保护，最终实现全流域的可持续发展。;The Yellow River Basin is a crucially ecological barrier and economic belt in China, whose ecological protection and sustainable development are of great importance to the national development strategy. However, the low water-use efficiency and the improvable allocation scheme of water resources have impeded the holistic achievement of sustainable development in the Yellow River Basin. Here, this study adopted the evenness among SDGs and investigated the differences in the performance of sustainable development goals (SDGs), developing pathways, dependence on the water resources from the Yellow River, and water-use efficiency for agriculture and industry among nine provinces in the upper, middle and lower basins. The coordinated development strategy was then discussed based on the optimal utilization of water resources. Our results showed that:(1) from 2000 to 2015, the sustainable development score of the nine provinces of the Yellow River Basin had increased significantly. The middle and lower basins had a significantly better performance of SDGs than the upper basin only when neglecting the evenness among SDGs. (2) The deviation caused by ignoring the evenness among SDGs was also reflected at the provincial level. For example, Ningxia and Shanxi were previously considered to achieve well performances towards SDGs. However, their development was mainly reflected in a few SDGs, whereas many SDGs related to environmental protection had fallen back (e.g., SDG15). These results suggested that the performance of SDGs might be overestimated without considering the evenness among goals. (3) Regardless of the location along the Basin, the water consumption in many provinces was dependent on the Yellow River. However, the industrial and agricultural water consumption and water-use efficiency largely varied among these provinces. Generally, the water-use efficiency in the upper basin was relatively lower compared with that in the middle and lower basins. (4) The correlations between the water withdrawal amount and the 17 SDGs were different in the upper, middle, and lower basins. The amount of water withdrawal in the upper basin was irrelevant or negatively correlated with most of the SDGs, indicating that the limiting factor for its sustainable development was not the water resources; while the increase in water withdrawal could promote some SDGs related to economic and social development in the middle and lower basins. Overall, this study points out that it is important to strengthen the cooperation among the upper, middle, and lower basins through optimizing the industrial structure and water resources allocation, which could further promote the overall water-use efficiency and the ecological conservation of the whole basin, and eventually achieve the sustainable development of the whole Yellow River Basin.