Water Shortage Situation Research Articles

Developing a Hyperspectral Remote Sensing-Based Algorithm to Diagnose Potato Moisture for Water-Saving Irrigation

Appropriate water supply is crucial for high-yield and high-quality potato tuber production. However, potatoes are mainly planted in arid and semi-arid regions in China, where the precipitation usually cannot meet the water demand throughout the growth period. In view of the actual situation of water shortage in these areas, to monitor the water status of potato plants timely and accurately and thus precisely control the irrigation are of significance for water-saving management of potatoes. Hyperspectral remote sensing has unique advantages in diagnosing crop water stress. In this paper, the canopy spectral reflectance and plant water content were measured under five irrigation treatments. The spectral parameters that respond to plant water content were selected, and a hyperspectral water diagnosis model for leaf water content (LWC) and aboveground water content (AGWC) of potato plants was established. It was found that potato tuber yield was the highest during the entire growth period under sufficient irrigation, and the plant water content showed a downward trend as the degree of drought intensified. The peak hyperspectral reflectance of potato plant canopies appeared in the red wavelength, where the reflectance varied significantly under different water treatments and decreased with decreasing irrigation. Six models with sensitive bands, first-order derivatives, and moisture spectral indices were established to monitor water content of potato plants. The R2 values of partial least squares regression (PLSR), support vector machine (SVM), and BP neural network (BP) models are 0.8418, 0.9020, and 0.8926, respectively, between LWC and hyperspectral data; and 0.8003, 0.8167, and 0.8671, respectively, between the AGWC and hyperspectral data. These six models can all predict the water content of potato plants, but SVM is the best model for predicting LWC of potato plants. These results are of great significance for guiding precision irrigation of potato plants at different growth stages.

Dynamic Variations of Agricultural Drought and Its Response to Meteorological Drought: A Drought Event‐Based Perspective

AbstractThe dynamic variations of agricultural drought can reflect the water shortage situation of the agricultural system, and there is a progressive relationship in the response of agricultural drought to meteorological drought on a spatiotemporal scale. In this study, the vegetation health index and the standardized precipitation evapotranspiration index were adopted as agricultural and meteorological drought indicators, respectively. Additionally, using the three‐dimensional spatiotemporal clustering technology, the dynamic evolutions of typical drought events were clarified, and the spatiotemporal response characteristics of agricultural drought to meteorological drought were revealed. The results indicated that: (a) there were 81 agricultural drought events in the North China Plain (NCP) during 1982–2020, with a largest drought severity (12.82 × 104 month km2), a 6‐month duration, and a 23.24 × 104 km2 affected area occurring in the No. 4 event; (b) from the 1980s to the 2010s, the agricultural drought gradually decreased and large‐scale droughts mainly concentrated in the border areas of Hebei, Shandong, and Henan; and (c) a total of 13 drought event pairs were successfully matched in the NCP, including 7 pairs of “one‐to‐one,” 4 pairs of “one‐to‐many,” 1 pair of “many‐to‐one,” and 1 pair of “many‐to‐many.” The spatiotemporal responses of agricultural drought were elucidated in a three‐dimensional perspective, which can propose a new approach for establishing drought propagation model, predicting future agricultural drought conditions, improving ecological environment quality, and can also be applied for the investigation of other drought types.

New challenges for Uruguayan viticulture

Climate scenarios in the medium and long term (2010-2070) foresee increased summer rainfall for Uruguay and the region, with increased water deficits and excess episodes. Although at the international level irrigation in viticulture has a long experience and tradition, at the local level (Uruguay), only 10% of the vineyard surface area implements a fixed or complementary system for water supply in their crops. This work aimed to model the crop water requirements for a vineyard in southern Uruguay based on pedo-climatic variables. In addition, the plant response to controlled deficit irrigation was evaluated in two consecutive seasons. The experiment was conducted in a 1.1 ha commercial vineyard in Canelones, Uruguay (34°36'S, 56°14W), during two successive seasons (2020-2021). The additional irrigation (I) treatment was compared against a control (C) without irrigation. A controlled water deficit was established from flowering to harvest. The adjustment in the demand was made as a function of a percentage of crop evapotranspiration. The Kc of the crop was estimated using digital tools. The simulation of the water balance made it possible to evaluate the vineyard water needs. Plants subjected to controlled deficit irrigation showed higher vegetative growth, positively impacting yield and the accumulation of sugars and anthocyanins in the berry. Based on our results, a supplementary water supply, at the right doses and time, allows us to face water deficit situations, positively impacting the productive and economic variables. Knowing the variability in a vineyard is necessary to achieve proper irrigation scheduling and optimize water use. New technologies applied to irrigation are an opportunity for winegrowers to obtain more sustainable vineyards and production.

Medium-term stochastic hydrothermal scheduling with short-term operational effects for large-scale power and water networks

The high integration of variable renewable sources in electric power systems entails a series of challenges inherent to their intrinsic variability. A critical challenge is to correctly value the water available in reservoirs in hydrothermal systems, considering the flexibility that it provides. In this context, this paper proposes a medium-term multistage stochastic optimization model for the hydrothermal scheduling problem solved with the stochastic dual dynamic programming algorithm. The proposed model includes operational constraints and simplified mathematical expressions of relevant operational effects that allow more informed assessment of the water value by considering, among others, the flexibility necessary for the operation of the system. In addition, the hydrological uncertainty in the model is represented by a vector autoregressive process, which allows capturing spatio-temporal correlations between the different hydro inflows. A calibration method for the simplified mathematical expressions of operational effects is also proposed, which allows a detailed short-term operational model to be correctly linked to the proposed medium-term linear model. Through extensive experiments for the Chilean power system, the results show that the difference between the expected operating costs of the proposed medium-term model, and the costs obtained through a detailed short-term operational model was only 0.1%, in contrast to the 9.3% difference obtained when a simpler base model is employed. This shows the effectiveness of the proposed approach. Further, this difference is also reflected in the estimation of the water value, which is critical in water shortage situations.

A new clearing method for cascade hydropower spot market

The natural hydraulic connections between cascade hydropower may make hydraulic and electric connections mismatch after the market clears. Aiming at relieving the contradiction between water surplus and water shortage after market clearing, this paper proposes a new market clearing method considering the coupling relationship between water and electricity. And the method is verified by the simulation of a virtual spot market consisting of eight stations in Sichuan Province, China. The main contributions of this paper lay on three aspects: firstly, a new index called water-electricity coupling degree (WCD) and its calculation method are proposed to measure the overall situation of water shortage and water abandonment in the clearing results. Secondly, a multi-objective clearing model for cascade hydropower stations is established with the goal of minimizing power purchase cost and maximizing WCD. Thirdly, a solution method combined with the characteristics of the clearing model is developed. The case results demonstrate that the built model increases the WCD value by 1.57 % and reduces the insufficient output and surplus water by 45.18 % without increasing the power purchase cost of the power grid; The proposed solution strategy lowers the complexity of the model and improves the solution efficiency, where the search space reduction and time period merging strategies can reduce the calculation time by about 3 % and 8 % respectively. The new clearing method provides a new idea for solving the uncoupling problem of water-electricity-price in the cascade hydropower spot market.

Perception of coastal citizens on the prospect of community-based rainwater harvesting system for sustainable water resource management

Predominant water scarcity and environmental degradation in Bangladesh's coastal communities arise due to extreme meteorological conditions, unrestrained water usage, and extensive saline intrusion into both surface and groundwater. This study leverages both quantitative data from a household survey and qualitative data from a Participatory Rural Appraisal to explore the perspectives of 150 official experts and 240 coastal public respondents regarding the implementation of a "Community-Based Rainwater Harvesting System" (CBRWHS) as a sustainable water supply technology in six major coastal districts of Bangladesh. Though CBRWHS surpasses the benefits of an individual harvesting system (IHS) due to its collective approach, high storage capacity, social cohesiveness, environmental benefits, and potential for scalability, findings suggest that the experts identify financial insolvency, lack of technical skills, and insufficient education as principal barriers against adopting CBRWHS. They propose that providing technical instructions, education, and establishing a CBRWHS pilot could serve as effective incentives. While expressing a sufficient understanding of IHS, respondents are willing to adopt CBRWHS only if financial support is provided. Given the residents' experience with IHS, they are cognizant of the financial and technical challenges intrinsic to such systems. CBRWHS, unlike IHS, operates as a shared system with collective property rights and regulations. Majority of respondents perceive CBRWHS as a potential significant mitigation tool against the water shortage situation since the challenges associated with harvesting, maintaining, and using rainwater could be addressed collectively by the user community. Similar to the official experts, public respondents identify a lack of technical expertise, financial constraints, and regulations as the most significant obstacles to IHS adoption. The findings of this study hold substantial implications not only for the local region but also for similar coastal regions worldwide, suggesting a crucial need for the prioritization of community-based solutions to water scarcity within the wider global discourse on sustainable water management.

Analysis of the Coupling Relationship between Water Quality and Economic Development in Hongjiannao Basin, China

Hongjiannao is the largest inland lake in China’s deserts. In recent years, the water quality and area of the Hongjiannao Lake have continued to decline, which is closely associated with the economic development in the Hongjiannao basin. To explore the coupling relationship between the water quality and economic development in the Hongjiannao basin, the water quality and economic development index of the basin has been analyzed in terms of the monthly water quality and socio-economic development from 2013 to 2020. The coupling relationship and interaction mechanism between water quality and regional economic development has been studied by coupling coordination degree model. The results show that the water pollution increased and then decreased with the seasons, while the water quality was the worst in the summer. The coordinated degree between the water quality and economic development in Hongjiannao shows an upward trend from 2013 to 2020, which has transformed from the process of lagging economic development to the process of primary coordination, finally to the process of lagging water environment. The coupling relationship between water quality and economic development changed from a state of nearly un-coordination to primary coordination from 2013 to 2016, with economic development lagging behind. The coupling relationship between the two systems changed from barely coordinated to the primary coordinated from 2017 to 2018, with the rapid development of economy and slight decline in water quality. After 2018, those two systems gradually stepped into a virtuous cycle during 2019–2020, but the phenomenon of lagging water quality still existed. Therefore, in order to maintain the stable economic development of resource-based cities, it is necessary to keep improving the current situation of water environment and water shortage in Hongjiannao, which will promote the coordinated and sustainable development of water environment and economy.

Research on emergy evaluation method of ecological water use efficiency based on comprehensive benefits.

Scientifically evaluating ecological water use efficiency (EWUE) is an effective means to regulate the level of ecological water use in a country or a region. It is also a basic work to achieve high-efficiency use of ecological water under the current situation of water shortage. However, there were few researches on EWUE, and existing studies only focus on eco-environmental benefits generated by ecological water, without considering its impact on economy and society. An emergy evaluation method for EWUE based on comprehensive benefits was proposed in this paper innovatively. Considering the impact of ecological water use on society, economy, and eco-environment, the concept of EWUE could be defined. Then, comprehensive benefits of ecological water use (CBEW) were quantified by emergy method, and EWUE was evaluated by the comprehensive benefits of unit ecological water use. Taking Zhengzhou City as an example for calculation, from 2011 to 2020, CBEW increased from 5.20 × 1019 sej to 6.72 × 1020 sej, showing an overall upward trend, and EWUE rose from 2.71 × 1011 sej/m3 (1.27￥/m3) to 1.32 × 1012 sej/m3 (8.10￥/m3) with fluctuation. It showed that Zhengzhou City has paid enough attention to the allocation of ecological water and EWUE at a high level. The method proposed in this paper provides a new idea to evaluate EWUE scientifically, and the results can provide guidance to allocate ecological water resources to achieve sustainable development.

Effectiveness of vegetation indices and UAV-multispectral imageries in assessing the response of hybrid maize (Zea mays L.) to water deficit stress under field environment.

Unmanned aerial vehicles (UAVs) equipped with multi-sensors are one of the most innovative technologies for measuring plant health and predicting final yield in field conditions, especially in the water deficit situation in rain-deprived regions. The objective of this investigation was to evaluate the individual plant and canopy-level measurements using UAV imageries in three different genotypes, Suwan4452 (drought-tolerant), Pac339, and S7328 (drought-sensitive) of maize (Zea mays L.) at vegetative and reproductive stages under WW (well-watered) and WD (water deficit) conditions. At the vegetative stage, only CWSI (crop water stress index) ofPac339 and S7328 under WD increased significantly by 1.86- and 1.69-fold over WW, whereas the vegetation indices (EVI2 (Enhanced Vegetation Index 2), OSAVI (Optimized Soil-Adjusted Vegetation Index), GNDVI (Green Normalized Difference Vegetation Index), NDRE (Normalized Difference Red Edge Index), and NDVI (Normalized Difference Vegetation Index)) derived from UAV multi-sensors did not vary. At the reproductive stage, CWSI in drought-sensitive genotype (S7328) under WD increased by 1.92-fold over WW. All the vegetation indices (EVI2, OSAVI, GNDVI, NDRE, and NDVI) of Pac339 and S7328 under WD decreased when compared with those of Suwan4452. NDVI derived from GreenSeeker® handheld and NDVI from UAV data was closely related (R2 = 0.5924). An increase in leaf temperature (Tleaf) and reduction in NDVI of WD stressed maize plants was observed (R2 = 0.5829) leading to yield loss (R2 = 0.5198). In summary, a close correlation was observed between the physiological data of individual plants and vegetation indices of canopy level (collected using a UAV platform) in drought-sensitive genotypes of maize crops under WD conditions, thus indicating its effectiveness in the classification of drought-tolerant genotypes.

Cellulose acetate/polyvinylidene fluoride based mixed matrix membranes impregnated with UiO-66 nano-MOF for reverse osmosis desalination

Reverse osmosis (RO) is considered a lifesaver technology to conquer the current catastrophic water shortage situation. However, reaching a competitive RO membrane is a challenging issue. Therefore, this study investigated the optimum polymeric blending ratio between cellulose acetate (CA) and polyvinylidene fluoride (PVDF) to have a new blended polymeric membrane named cellulose acetate polyvinyl (CAPV-X), where X is the PVDF concentration %, with enhanced properties. The optimum prepared CA/PVDF blended membrane was selected for further enhancement with nano sized metal organic framework (UiO-66 MOF). Selection was made depending on each membrane salt rejection. A membrane characterization was performed based on Fourier transform infrared (FTIR), X-ray diffractometer (XRD), scanning electron microscope, thermal gravimetric analysis, and contact angle. FTIR and XRD data confirmed the successful preparation of the blended polymeric membranes CAPV-5, CAPV-7 and CAPV-10. Further, they proved UiO-66 nanofiller impregnation in the hybrid CA/PVDF/UiO-66 membrane (CPU). The addition of PVDF and nano-MOF had a slight positive effect on the membrane thermal stability. The contact angle increased with increasing the PVDF concentration and decreased once more with the impregnation of UiO-66. The RO membrane performance revealed that the optimum CA/PVDF ratio was found to be 93/7% with around 80% salt rejection and a permeate water flux of 4 L/m2 h. CPU composite membrane was then fabricated to enhance salt rejection and permeate water flux. The testing data indicated that salt rejection and permeate water flux increased over blended CAPV-7 membrane by almost 12% and 42%, respectively. Overall, CPU hybrid membrane could be used for water desalination with a good salt rejection of 90.2% and a permeate water flux of 5.7 L/m2 h.Graphical abstract

Modeling and optimization of pressure and water age for evaluation of urban water distribution systems performance

Water loss has become increasingly critical as the severity of the water shortage situation has grown in recent decades. One of the options for reducing water loss in urban water distribution networks is pressure management. The study aimed to evaluate and optimize the existing water distribution system in the city. The proposed methodology is an interactive combination process between an optimization algorithm and WaterGEMS V8i to evaluate the performance of the distribution system. It was observed that, 43.80% of nodes (15–60 mH2O), 5.10% of nodes (15 mH2O), and 51.10% of nodes (>60 mH2O) received pressure during peak hour demand. During low demand periods, only 4.4% of nodes (15–60 mH2O) and 95.60% of nodes (>60 mH2O) received pressure. The water age simulation results revealed that, 51.70% of the pipes were received water age <4.8 h, whereas the other 48.3% of the pipes were received water age <8.6 h during peak hour demand. During low demand periods, 45.58% of the pipes had a water age of less than 4.8 h while the other 54.42% of the pipes had water age of 4.8–20 h. The optimization result showed that after optimization, 4.4% of the nodes with optimum pressure increased to 75.18%, and 95.6% of the nodes decreased to 24.82%. Changing the size of the pipe based on the optimization result, and dividing an area into different pressure zones (adding more reservoirs at the far end of the distribution system) are all ways to improve or upgrade the distribution system.

Predicting the Impact of Internet of Things on the Value Added for the Agriculture Sector in Iran Using Mathematical Methods

In terms of water resources, Iran has less fresh water than its population demands. Also, due to climate change, inefficient management and excessive consumption of this vital resource, the water shortage situation is becoming more critical day by day. Searching for a solution for sustainable use of water sources, this study proposes utilizing the Internet of things technology in order to implement smart irrigation in agricultural lands in Iran. Investigating the economic impact of the Internet of Things in Iran’s agriculture sector is the purpose of this article. The most important advantages of using smart irrigation are decreasing water consumption and increasing the productivity of agricultural yields (e.g., fruits, vegetables, etc.). This research attempts to predict Iran's economic growth in the event of smart irrigation implementation in agricultural fields and farms. The effect of investment in smart irrigation on water consumption and agricultural production is estimated by regression with cross-sectional data. In the end, by using the information obtained through the mathematical method, Iran's economic growth through GDP growth is estimated in the case if the Internet of things technology is fully implemented and the full benefits of using this technology are gained.

Analysis of Water Supply-Demand Based on Socioeconomic Efficiency

Water resource is an important factor restricting social-economic development. Hebei Province is one of the regions suffering from severe water shortage in China. Based on the Water Resources Assessment and Planning model, population growth, economic growth, water-saving, and integrated scenarios were established. The water demand and supply in Hebei Province in 2025 and 2035 were forecasted in this study. The research results show that agriculture is the main unmet water demand sector. In the absence of large-scale population inflows, the local population growth has little impact on the changes in water supply-demand. Economic development is one of the main factors affecting water balance. The water-saving scenario has the greatest impact on water supply-demand. Compared to population and economic growth scenarios, the simulation results of water demand and unmet water demand were the smallest. Under an integrated scenario, the current situation of water shortage in Hebei has been greatly improved, but there is still a demand shortage of44.12×108 m3 in 2030. It is necessary to take measures to improve the carrying capacity of water resources in various regions of Hebei Province and narrow the regional gap. This study provided a reference for the rational utilization of water resources.

Application of Harris Hawks Optimization with Reservoir Simulation Model Considering Hedging Rule for Network Reservoir System

This research aims to apply the Harris hawks optimization (HHO) technique connected with a reservoir simulation model to search optimal rule curves of the network reservoir system in Thailand. The downstream water demand from the network reservoir that required shared water discharge, hydrological data, and physical data were considered in the reservoir simulation model. A comparison of the situation of water shortage using optimal rule curves from HHO technique, genetic algorithm (GA), and wind-driven optimization (WDO) is presented. The results showed that the new rule curves derived from the HHO technique with network reservoir searching were able to alleviate the water shortage and over-flow situations better than the current rule curves. The efficiency of using rule curves from HHO technique compared to GA and WDO techniques showed that the HHO technique can provide a better solution that reduced water scarcity and average over-flow compared with the current rule curves by up to 4.80%, 4.70%, and 4.50%, respectively. In addition, HHO was efficient in converging rule curve solutions faster than GA and WDO techniques by 15.00% and 54.00%, respectively. In conclusion, the HHO technique can be used to search for optimal network reservoir rule curves solutions effectively.

Sustainability of Water Resources in Shandong Province Based on a System Dynamics Model of Water–Economy–Society for the Lower Yellow River

The sustainability of water resources is a common issue for all human beings. In order to solve the water resource shortage problem in the lower Yellow River region of China, this paper uses a system dynamics approach from the perspective of a water–society–economy coupled model for the sustainable utilization of water resources in the lower Yellow River region in Shandong province. The model was validated using the water quantity, economic, and demographic statistics of nine prefecture-level cities in Shandong province from 2011 to 2020. Based on this model, three analysis scenarios were set up. The sustainability of water resources in the lower Yellow River region of Shandong province was analyzed by integrating and regulating indicators in the coupled model. The research shows that, with the liberalization of the population policy, water shortages will become critical. However, by appropriately reducing the water consumed for economic needs, water deficiency can be resolved. According to the forecast of scenario analysis, scenario 3 (the Sustainable development scenario) was chosen as the optimum solution. Assuming that the growth rate of agricultural and industrial production is controlled to reduce water consumption, the water deficiency rate of Shandong province will decrease year by year, and eventually the water shortage situation will gradually improve from 2022.

Foliar brassinosteroid analogue (DI-31) sprays increase drought tolerance by improving plant growth and photosynthetic efficiency in lulo plants

The use of agronomic alternatives such as plant hormone sprays has been considered a tool to mitigate drought stress. This research aimed to evaluate the use of foliar brassinosteroid analogue DI-31 (BRs) sprays on plant growth, leaf exchange and chlorophyll a fluorescence parameters, and biochemical variables in lulo (Solanum quitoense L. cv. septentrionale) seedlings grown under drought stress conditions. Seedlings were grown in plastic pots (3 L) using a mix between peat and sand (1:1 v/v) as substrate. Lulo plants were subjected to drought stress by suppressing 100% of the water needs at 30–37 and 73–80 days after transplanting (DAT). Foliar BRs analogue (DI-31) sprays were carried out at four different rates (0, 1, 2, 4, or 8 mL of analogue per liter) at different times (30, 33, 44, 60, 73, and 76 DAT). Drought stress caused a reduction in the Fv/Fm ratio, leaf gas exchange properties, total biomass, and relative water content. Foliar DI-31 sprays enhanced leaf photosynthesis in well-watered (WW) (∼10.7 μmol m−2 s−1) or water-stressed plants (WS) (∼6.1 μmol m−2 s−1) when lulo plants were treated at a dose of 4 and 8 mL·L−1 compared to their respective controls (0 mL·L−1 for WW: 8.83 μmol m−2 s−1 and WS: 2.01 μmol m−2 s−1). Also, DI-31 sprays enhanced the photochemical efficiency of PSII, and plant growth. They also increased the concentration of photosynthetic pigments (TChl and Cx + c) and reduced lipid peroxidation of membranes (MDA) under drought conditions. The results allow us to suggest that the use of DI-31 at a dose of 4 or 8 mL·L−1 can be a tool for managing water stress conditions caused by low water availability in the soil in lulo-producing areas to face situations of moderate water deficit at different times of the year.

Study of ecological water-demand security in the Linghekou Reserve of north-eastern China, based on landscape pattern

Context The socio-economic development and the expansion of urbanisation boundaries are constantly eroding the ecological resources of wetlands, making them deteriorate, weakening their ecological functions and making the phenomenon of water shortage within them obvious. Aim Through the study of water-demand model and water distribution process in coastal wetlands, we cannot only improve the current situation of water shortage within wetlands and optimise water allocation, but also improve the research content of ecological water demand in wetlands. Methods In this study, Remote Sensing and Geographic Information System technology were used to study the landscape distribution characteristics and ecological water demand of the Linghekou Reserve, on the basis of the landscape pattern index and ecological water-demand model. Key results The ecological water demand decreases year by year, with obvious spatial and temporal variability, and the areas with higher ecological water demand are located mainly in the central and southern parts of the reserve. Among the total ecological water demand, the biological habitat has the largest proportion of water demand, and plays an important role in ensuring the water-demand security of the reserve. Conclusion The ecological environment quality of the reserve not only affects the landscape distribution characteristics, but also influences the total ecological water demand. Implications This study provides a research reference for water-shortage problems caused by ecological imbalance, and provides a scientific basis for other wetland-related problems in north-eastern China.

Impacts of COVID-19 on daily water use: Have people started using more water?

In São Paulo, as well as every other city around the world, water is an invaluable natural resource. More than a necessary input for production and a strategic resource for economic development, it is vital for the maintenance of biological, geological, and chemical cycles, which keep ecosystems in balance. There is a shortage of water in the world, and this situation is aggravated by social inequality, the lack of sustainable management, and use of natural resources. The purpose of this research was to discover if, during the quarantine of COVID-19, there was an increase in the daily use of water in the city of São Paulo and, if this happened, to understand why and to investigate its impact on reservoirs. We hypothesized that, during the COVID-19 quarantine, water consumption increased exponentially due to virus precautions. Based on our hypothesis, we carried out a survey where we interviewed 100 people in the São Paulo capital. Most reported that water consumption in their homes increased, according to our research; for example, we discovered that individuals who took an average of five-minute showers increased their time to sixteen-minute showers. This phenomena worsened the water shortage situation in many reservoirs in São Paulo. The findings from our study can be used to further help solve water waste problems.

Selection of Water-Saving Plants and Annual Water Consumption Estimation for Garden Green Spaces in Beijing

Currently, the number of urban garden green spaces (GGSs) being constructed in Beijing is increasing, and their high water resource demands contradict the severe water shortage situation in Beijing that is restricting urban construction and economic development. This has created an urgent need to build water-saving GGSs. This study analyzed and compared the daily/annual water consumption of 79 common plants in Beijing, and low-water-consumption (LWC) trees, shrubs and herbs were selected; additionally, the total annual water consumption (TAWC) of all plants in the built-up areas of all 16 districts in Beijing was calculated according to the result of the eighth general survey of landscaping resources in Beijing. The results are as follows: (1) fifteen LWC tree species were selected from among 25 species, and the average daily water consumption (DWC) was &lt;1.09 kg·m−2; (2) nineteen LWC shrubs were selected from among 35 shrubs, and the average DWC was &lt;1.17 kg·m−2; (3) eleven LWC herbs were selected from among 19 herbs, and the AWC was &lt;460.3 kg·m−2; (4) the TAWC of all trees, shrubs and herb plants in the Beijing GGSs was 1.104 × 109, 0.139 × 109, and 0.16 × 109 m3, respectively. Based on the above results, it was estimated that the TAWC of all plants in the built-up areas of all 16 districts in Beijing is approximately 1.403 × 109 m3. These findings provide a better understanding of the water consumption of GGS plants in cities in semiarid and semihumid climates and can be used to help select LWC greening plants that can reduce water consumption when expanding green areas in cities.

Water-Saving from Rehabilitation of Irrigation Canals Case Study: El-Sont Canal, Assiut Governorate

In light of the national project for rehabilitation and the lining of the exposed irrigation canals which is currently under implementation all over Egypt, a field study is introduced to assess the technical, and environmental expected impacts that must be achieved in such a national project. In arid and semi-arid regions, with permeable soils like Egypt, water seeps significantly through the exposed canals cross-sections, in addition to the quantities lost by evaporation under high temperatures. Saving such tangible quantities of water became the most important goal that can be achieved to solve the problematic situation of irrigation water shortage that faces Egypt nowadays. This study is a field attempt to estimate the transmission losses in the El-Sont canal in Middle Egypt (Assuit Governorate) as a representative open channel for a specific type of soil, climate, topography, and beneficiary’s lifestyle. Using the recommended equations developed by the most popular reviewed researchers, the conveyance and transmission losses for the understudy El-Sont canal, and its off-taking canals were calculated and evaluated to be about 248628 m3/day, i.e., more than 39.54 Mm3/year. That big quantity of saved or recovered water can be used for reclamation and irrigation of about five thousand new acres in the nearby area. The study and the field trips, visits, and the personal direct communication with the farmers and beneficiaries proved that the project had responded to their hopes for an improved living standard, health, in addition to the environmental situation for all the Egyptian countryside.