Water Utilization Efficiency Research Articles

Effect of Different Irrigation Levels and Methods of Humic Acid Addition on Growth, Yield and Storability of Garlic

A field experiment was carried out to study the effect of different levels of irrigation at 40%, 60% and 80% of available soil moisture depletion (ASMD) and humic acid application methods (without, soil application, foliar application and soil application + foliar) on growth, productivity and storability of garlic cv. Sids-40. Results indicated that highest values of irrigation water applied (IWA),were found to be 3359 and 3162 m3/fed due to 40% ASMD comparison with other two irrigation treatments in both seasons respectively. Also, results reveal that 80% ASMD irrigation treatments could save about 31.0% and 29.8% of the applied water, compared with 40% ASMD in both seasons respectively. Furthermore, the irrigation after depletion of 40%, 60% ASMD with applying soil conditioner and foliar application of humic acid increased the plant length, leaves number, neck diameter, bulb diameter, bulb fresh weight, fresh and dray weight of plant as well as the yield of bulbs, cloves fresh weight/bulb, cloves number/bulb, bulb diameter, neck diameter, average clove weight, nitrogen, phosphors, potassium and carbohydrates content. While, the proline and total pungency of garlic increased significantly and the percentage of weight loss (%) after two, four and seven months of the storage as a result of irrigation decreased after 80% ASMD with soil application plus spraying with humic acid. Also, average water utilization efficiency, increased by using 60% ASMD with soil and foliar application of humic acid (HS+ HF) followed by 80% ASMD with HS+ HF then 40% ASMD treatments with HS+ HF in both seasons.

Regional Assessment of Land and Water Carrying Capacity and Utilization Efficiency in China

In response to the severe situation of water and land resources in China, this paper uses the DPSIR (driving force–pressure–state–impact–response) model and two-stage network DEA (data envelopment analysis) model to evaluate the carrying capacity and utilization efficiency of land and water resources in 31 provinces of China from 2009 to 2017. The empirical results show that the carrying capacity and the efficiency values of land and water resources in most areas of China do not perform well and show a downward trend during the sample period. Specifically, the carrying capacity of land and water resources show a decreasing trend from north to south and from east to west. In addition, the response to the current situation of land and water resources has an important influence on the carrying capacity. The utilization efficiency of water and soil resources is significantly different in the two stages in most regions, indicating that the efficiency of economic benefit transformation is far greater than land and water resources development. Our results shed some insights on land and water utilization efficiency management and provide political recommendations for different regions.

Water Resources Allocation Based on Complex Adaptive System Theory in the Inland River Irrigation District

Water resources are the key factors affecting the sustainable development of inland river irrigation districts. The establishment of a water resources management model is helpful to realize the coordinated development of water, society, and ecology. Aiming at the contradiction of water use and ecological vulnerability, this study was based on the method of complex adaptive system (CAS) theory, and an agent-based modeling (ABM) method was adopted. Taking Huaitoutala irrigation district as the research object, a water resource management model considering ecological balance was established, with the water resources potentially tapping in the source area as an effective constraint. This study took 2016 as the datum year; the water consumption and comprehensive benefits of four water-saving irrigation scenarios in different characteristic years were simulated and optimized under the conditions of the current water supply and 10% and 15% potential water resources tapping. The results showed that the model considering the behavior and adaptability of the agent can well optimize and simulate the water use in the irrigation district. Under the application of water resources potential tapping and high-efficiency water-saving technology; the water utilization efficiency (WUE) of the irrigation area has been significantly improved. The comprehensive benefits of the irrigation district increased the proportion of ecological water, which was conducive to the sustainable development of the irrigation district and the ecological protection of inland rivers.

Increasing the energy efficiency of water inlets by re-using washed water and reducing filter cycle time

PURPOSE. The purpose of this article is to study the search for ways to reduce energy consumption and develop methods for increasing the energy efficiency of water utilities. The studies reflected in the article are based on the results of an energy survey of a water utility in the city of Gomel (Republic of Belarus), one of the tasks of which is the search for reserves for saving fuel and energy resources by reducing technological water consumption. The article presents the results of research on the example of two water intakes «Iput» and «Sozh». METHODS. When solving the problem, the methods of mathematical statistics were used, including the method of analysis of variance to assess the significance of the effect of water flushing on reducing the iron content. RESULTS. The article discusses possible ways to reduce energy costs by reducing technological water consumption, which are used to flush filtering structures. The main activities are the following: changing the filter flushing schedule with increasing the filter cycle; the use of water-air flushing; reuse of wash water. The article formulates a hypothesis: filter flushing leads to a decrease in the iron content in the water, i.e. improving the quality of cleaning. CONCLUSION. An increase in the energy efficiency of water intakes, along with measures to modernize and optimize the operation of pumping equipment, is achieved by saving water resources and, accordingly, the cost of electricity for their extraction, which is necessary when flushing the filter materials of the deferrization station. The assumption about a possible increase in the filtration cycle was the lack of significance of the influence of washing on the decrease in the iron content, which indicated the presence of a significant reserve of the washing cycle. The use of combined water and air flushing contributes to a significant reduction in both technological water consumption (40.1%) and electricity consumption (38.8%). The energy saving potential due to the reduction of technological energy consumption for lifting water for the purpose of flushing reached 89857 kWh / year for the studied water intake.

Increasing the energy efficiency of water inlets by re-using washed water and reducing filter cycle time

PURPOSE. The purpose of this article is to study the search for ways to reduce energy consumption and develop methods for increasing the energy efficiency of water utilities. The studies reflected in the article are based on the results of an energy survey of a water utility in the city of Gomel (Republic of Belarus), one of the tasks of which is the search for reserves for saving fuel and energy resources by reducing technological water consumption. The article presents the results of research on the example of two water intakes «Iput» and «Sozh». METHODS. When solving the problem, the methods of mathematical statistics were used, including the method of analysis of variance to assess the significance of the effect of water flushing on reducing the iron content. RESULTS. The article discusses possible ways to reduce energy costs by reducing technological water consumption, which are used to flush filtering structures. The main activities are the following: changing the filter flushing schedule with increasing the filter cycle; the use of water-air flushing; reuse of wash water. The article formulates a hypothesis: filter flushing leads to a decrease in the iron content in the water, i.e. improving the quality of cleaning. CONCLUSION. An increase in the energy efficiency of water intakes, along with measures to modernize and optimize the operation of pumping equipment, is achieved by saving water resources and, accordingly, the cost of electricity for their extraction, which is necessary when flushing the filter materials of the deferrization station. The assumption about a possible increase in the filtration cycle was the lack of significance of the influence of washing on the decrease in the iron content, which indicated the presence of a significant reserve of the washing cycle. The use of combined water and air flushing contributes to a significant reduction in both technological water consumption (40.1%) and electricity consumption (38.8%). The energy saving potential due to the reduction of technological energy consumption for lifting water for the purpose of flushing reached 89857 kWh / year for the studied water intake.

Assessment of Epigenetic and Phenotypic Variation in Populus nigra Regenerated via Sequential Regeneration.

Somatic variation has been demonstrated in tissue culture regenerated plants of many species. In the genus Populus, phenotypic variation caused by changes in 5-methylcytosine within the plant genome have been reported. To date, the phenotypic and epigenetic stability of plants regenerated from sequential regeneration has not been tested in trees. In this study, we detected DNA methylation of CCGG sites in regenerated plants of five generations in Populus nigra using methylation-sensitive amplified polymorphisms, and evaluated their growth performance and physiological traits. About 10.86–26.80% of CCGG sites in the regenerated plant genome were demethylated and 5.50–8.45% were methylated, resulting in significantly lower DNA methylation levels among all regenerated plants than among donor plants. We detected a significant difference in methylation levels between first regeneration regenerated plants (G1) and those of the other four generations (G2–G5); there were no significant differences among the four later generations. Therefore, the dramatic decrease in DNA methylation levels occurred only in the first and second poplar regenerations; levels then stabilized later in the regeneration process, indicating that two regeneration events were sufficient to change the methylation statuses of almost all CCGG sites sensitive to regeneration. Differences in growth and physiological traits were observed between regenerated plants and donor plants, but were significant only among plants of certain generations. Significant correlations were detected between methylation level and transpiration rate, net photosynthetic rate, peroxidase activity, and instant water utilization efficiency, indicating the involvement of epigenetic regulation in this unpredictable phenotypic variation.

灌溉定额和施氮量对机采棉田水分运移及硝态氮残留的影响

<p id="C3">The shortage of water resources and the excessive investment of fertilizer are the bottlenecks that restrict the sustainable and healthy development of agriculture and force farmers to develop and adopt sustainable production technologies. The mechanism of water movement and the residual behavior of nitrogen fertilizer are important scientific issues to evaluate the level of agricultural water and fertilizer management in arid areas. Improving the water and nitrogen utilization efficiency was an important way to reduce environmental pollution. An experiment was conducted using a split plot design with the main area for total irrigation of 2250 (W1, non-sufficient drip irrigation), 3450 (W2, conventional drip irrigation), 4650 m ³ hm ^-2 (W3, saturated drip irrigation), and the deputy area of nitrogen (pure N) including 0 (N1, no fertilizer), 300 (N2, conventional fertilization), 600 kg hm ^-2 (N3, excess fertilization) in arid area of northwest China cotton region from 2018 to 2019. The effects of irrigation and nitrogen levels on water distribution, nitrate nitrogen residue, seed cotton, irrigation water, and N fertilizer productive efficiency were evaluated. The results revealed that irrigation and coupling effects of irrigation and nitrogen levels were the influencing factors on seed cotton and water utilization efficiency, among which irrigation was the main effect. Two-year average values demonstrated that the irrigation was W1, nitrogen fertilization amount increased from N1 to N3, and the average soil moisture content of 0-80 cm during the whole growth period increased first and then decreased. Compared with N1 fertilization application, seed cotton yield was 13.8% and 7.6% higher and irrigation water productive efficiency were 13.6% and 6.8% higher under N2 and N3 fertilization application, respectively. When the irrigation was W2 and W3, the nitrogen fertilization amount increased from N1 to N3, and there was no significant difference in the average soil moisture content of 0-80 cm during the whole growth period. Compared with N1 fertilization application, seed cotton yield was 11.4% and 11.5% higher and irrigation water productive efficiency were 13.6% and 6.8% higher under N2 and N3 fertilization application, respectively. With the increase of irrigation, the total average value of 0-80 cm during the whole growth period gradually increased. Irrigation was the main effect on soil nitrate nitrogen accumulation in the main distribution area of 0-40 cm roots, and coupling effects of irrigation and nitrogen levels was the main factor leading to nitrate nitrogen leaching. When the irrigation was W1, nitrate nitrogen accumulated in the 0-40 cm with the increase of nitrogen. And when the irrigation was W3, nitrate nitrogen accumulated in the 40-60 cm with the increase of nitrogen. In conclusion, if the irrigation was higher than 3450 m ³ hm ^-2 and nitrogen was higher than 300 kg hm ^-2, the continued increase of water and nitrogen input failed to increase production, which might result in resource waste and potential pollution to the environment. Therefore, we suggest that water and nitrogen optimization strategies can improve resource utilization efficiency, reduce water and fertilizer input, and healthy development of agriculture.

The impact of increasing environmental requirements on the efficiency of water utilities: Russian case

The impact of increasing environmental requirements on the efficiency of water utilities: Russian case

Production Performance and Nitrogen and Phosphorus Mass Balance in Biofloc-based African Catfish Intensive Culture at Different Densities

This study aimed to evaluate the production performance and nitrogen and phosphorus mass balance of biofloc-based intensive African catfish Clarias gariepinus culture at different densities. African catfish with an average body weight of 2.64 ± 0.06 g was randomly distributed into 12 units of round tank with a working volume of 2 m3 of water and maintained for 8 weeks. A completely randomized experimental design with four treatments (in triplicates), i.e. a control treatment at a fish density of 500 fish m-3 with regular water exchange and without organic carbon source addition, and biofloc treatments (BFT) at three different densities, i.e. 500 fish m-3 (BFT500), 750 fish m-3 (BFT750), and 1000 fish m-3 (BFT1000). Biofloc systems were performed with a regular addition of tapioca flour (40% C). The production performance between biofloc system and the control was not significantly different, however water and nitrogen utilizations were significantly more efficient in biofloc system than those of the control. The highest fish specific growth rate was observed in BFT1000 and BFT500 (6.01% day-1 and 5.96% day-1, respectively) (P&lt;0.05). Fish density significantly affected the fish growth performance and productivity in biofloc systems, but not nitrogen and phosphorus utilizations. In conclusion, higher fish density significantly increased the production and water utilization efficiency in biofloc systems, but has no effect on nitrogen and phosphorus utilization efficiency. Furthermore, increasing the fish density could significantly reduce the fish survival and require more efforts to control biofloc biomass in the culture system.

Assessing Energy Efficiency in Water Utilities Using Long-term Data Analysis

Assessing Energy Efficiency in Water Utilities Using Long-term Data Analysis

Performance of prestressed concrete beams using magnetic water for concrete mixing

Civil engineering network is virtually orient to develop high-performance materials with eco-friendly construction to welfare of the society. Undoubtedly, water plays an important role in the performance of concrete to provide workability, strength, and other durability properties. Magnetic water being salt free and its properties are turning out to be as good as potable water. When water is passing through a magnetic field, water molecules get rearranged inside the structure, which allows the water to seep through more effectively than normal water in cementitious particles, thereby enabling the hydration process to operationalize faster and effective. Based on the preliminary studies, it has observed that workability of M40 grade concrete mixed with magnetic water is improved significantly without compromising its strength and also it has been observed that the strength achievement is faster than the conventional concrete with the considerable reduction of cement content. This research paper intends to investigate the efficient utilization of magnetic water in M40 grade concrete and to study the enhancement of its properties on hardened concrete and structural behavior of prestressed concrete (PSC) beams such as load carrying capacity, ductility factor, and energy absorption capacity. These properties are comparatively studied for pre-tensioned reinforced concrete (RC) beam subjected to central concentrated load for concrete mixing to use the normal water and magnetic water. Utilization of magnetic water on pre-tensioned concrete beams is improving the flexural strength by 25%. The characterization study on concrete with magnetic water such as X-ray diffraction (XRD) and Fourier-transform infrared (FT-IR) spectroscopy substantiates hydrated products of cements at early ages. Further the scanning electron microscopic (SEM) studies demonstrate the high degree of hydration of cement with separation of calcium hydroxide (CH) crystal using magnetic water.

Efficiency analysis of metacoupling of water transfer based on the parallel data envelopment analysis model: A case of the South–North Water Transfer Project-Middle Route in China

The deepening of globalization and the rapid socio-economic development have contributed to the increasing demand for water resources, which intensified the problem of water shortage. Cross-regional water transfer is an effective measure to alleviate the contradiction between the supply and demand of regional water resources. However, due to the strong interaction among the water source area, water-receiving area and the downstream of the water source area in the water transfer project, how to measure the impact of metacoupling of water transfer remains to be explored. Firstly, this study constructs the input and output indicators of the model. The input indicators are mainly based on Water Transfer, while the output indicators emphasize the economic, social and ecological benefits of water used by provinces and cities, which facilitates the measurement of the metacoupling. Secondly, the evaluation framework for the parallel data envelopment analysis (DEA) model of metacoupling of water transfer was built from the perspective of efficiency. This framework divides the metacoupling of the water transfer project into intracoupling, pericoupling and telecoupling, and opens the internal structure of the traditional DEA system. By calculating the efficiency of each system and using the weighted average method, the overall efficiency and the efficiency of each part of water transfer can be evaluated. In addition, the overall efficiency can be optimized by adjusting the proportion of water resources. The main results are: (Ⅰ) The overall water efficiency of the Middle Route of China's South-North Water Transfer Project is high, at above 0.7, with intracoupling(0.605)<pericoupling(0.818)<telecoupling(1.088). (II) The water source area and the downstream area have the most obvious improvement in water consumption efficiency, while the northern water-receiving areas have shown small improvement. The evaluation of water utilization efficiency can help to identify problems such as irrational water use structure, inefficient water consumption and water waste, and the water utilization efficiency can be improved by optimizing the proportion of water transfer.

Approach for optimizing the water-land-food-energy nexus in agroforestry systems under climate change

CONTEXTAgroforestry systems are widely promoted for their economic and environmental benefits. Food, energy, water and land resources in agroforestry systems are inextricably intertwined and expected to be severely impacted by climate change. Socioeconomic development and increasing populations have posed unique challenges for meeting the demand for food, energy, water and land, and the challenge will become more pressing under projected resource shortages and eco-environmental deterioration. Thus, a method of optimizing and sustainably managing the water-land-food-energy nexus in agroforestry systems under climate change must be developed. OBJECTIVEThis paper develops an optimization model framework for the sustainable management of limited water-land-food-energy resources in agroforestry systems under climate change. The aims are to (1) quantify the interactions and feedbacks within water, land, food and energy subsystems; (2) provide trade-offs among water and energy utilization efficiency, economic benefits and environmental protection in agroforestry systems; and (3) generate optimal policy options among water and land resources for different crops and woodlands in different regions under different climate change patterns. METHODSThe model framework is based on multiobjective fractional programming, and compromise programming is used to solve it. Climate change patterns are obtained from atmospheric circulation models and representative concentration pathways. The above aims are investigated through an actual nexus management problem in northeast China. Spatiotemporal meteorological and report-based databases, life cycle assessments, Pearson correlation analyses, data envelopment analyses and analytic hierarchy processes are integrated to realize practical application. RESULTS AND CONCLUSIONSThe results show that climate variation will change the water and land allocation patterns and these changes will be more pronounced for major grain-producing areas. The optimized water allocation decreased (especially for rice, e.g., the optimal average value of the irrigation quota of rice was 4226 m3/ha, while the corresponding actual irrigation requirement of rice was [4200–7200] m3/ha) to improve the water use efficiency, and surface water allocation accounted for two-thirds. Maize had the largest planting area, although planting soybean generated the most greenhouse gases (greenhouse gas emissions from field activities for rice, maize, and soybean were 43.46%, 84.06% and 91.16%, respectively); However, these gases can be absorbed by forests. The model improved the harmonious degree of the resource-economy-environment system from 0.24 to 0.56 after optimization. SIGNIFICANCESIntegrated models contribute to the sustainable management of water, food, energy and land resources and can consider the complex dynamics under climate change. It can be used as a general model and extended to other agroforestry systems that show inefficient agricultural production.

Production and scale efficiency of South African water utilities: the case of water boards

AbstractSouth Africa is a water scarce country with deteriorating water resources. Faced with tight fiscal and water resource constraints, water utilities would have to adopt technically efficient water management technologies to meet developmental socio-economic objectives of universal coverage, aligned to the United Nation's Sustainable Development Goal 6. It is important to measure the technical efficiency of utilities as accurately as possible in order to inform policy. We do this by using a non-parametric method known as Data Envelopment Analysis to determine, measure, analyse and benchmark the technical efficiency of all water boards in South Africa. Our contribution to the literature is twofold: This is the first paper to model technical efficiency of water boards as utility suppliers and guardians of water services in South Africa, and second, we address the over- and underestimation issues of technical efficiency measurement in the water sector. We do this by modelling one of the most pronounced negative externalities from water provision (water losses) as an undesirable output using the approach developed by You and Yan. We find, on average, technical efficiency of water boards is 49%, with only three of the nine water boards technically efficient. Six of the smaller water boards showed high levels of inefficiency with an inefficiency rate of 51%, which is equivalent to wastage in expenditure of R3.7 billion. Six water boards operate at increasing returns to scale and two are scale efficient. Only Rand and Sedibeng water boards exhibited decreasing returns to scale. Therefore, redirecting potential efficiency savings to optimal uses could result in technical and scale efficiency for the sector. Scale efficiency results seem to support larger regional water boards as small- to medium-sized water boards are scale inefficient with low technical efficiency. For example, Amatola Water (small water board) with an efficiency score of only 16% has a total expenditure of 18% of that of Umgeni (large water board), but sells only 6.7% of the quantity sold by Umgeni. Amatola also has seven times the proportion of water losses compared with Umgeni and charges 1.6 times the tariff of Umgeni. The ratio model with an undesirable output outperforms previous methods to deal with undesirable (bad) outputs, which either provide an over- or underestimation of technical efficiency.

Enhancing yellow maize production for sustainable food and nutrition security in Kenya

Maize is a strategic staple crop serving both as human food and feed in the livestock sector. It therefore has a critical socioeconomic value safeguarding against food and nutrition insecurity. Maize yields are however low especially among smallholder farmers who rely on this crop for their livelihood and sustenance. This has rendered most Sub-Saharan Africa countries such as Kenya to be net importers and depended on food aid mainly in form of maize. Even though white maize variety is nutritionally inferior, it is the most produced and consumed with little regard placed on yellow maize. We reviewed 154 articles and reports to highlight challenges facing maize production and sustainable agricultural practices that should be embraced to overcome them, nutritional benefits of yellow maize, factors hindering its consumption and research gaps that need to be addressed to enhance its production and utilization. Key production challenges identified include shrinking land sizes, declining soil fertility, adverse and unpredictable weather patterns and the devastating striga weed. Intercropping especially cereals with legumes have great potential for efficient land, water and nutrient resource utilization, manage weeds and minimize crop failure and adverse weather effects. This combined with integrated soil fertility management will ensure increased yields. It was found that yellow maize has higher carotenoid content hence superior to white maize and when taken with grain legumes provides a low-cost balanced diet. Despite this, yellow maize utilization is low because it is regarded as poor man’s crop, associated with food aid and reserved as livestock feed. This negative perception can be changed through educational campaigns on its nutritional value in order to enhance local production and encourage social acceptability to aid alleviate vitamin A deficiency, a key limiting micronutrient. In conclusion, tapping in the nutritional superiority of yellow maize through legume intercropping should be enhanced.

A GIS-Based Model to Assess the Potential of Wastewater Treatment Plants for Enhancing Bioenergy Production within the Context of the Water–Energy Nexus

The necessity of developing renewable energy sources has contributed to increasing interest in developing the anaerobic digestion for producing biomethane since it both provides green energy and reduces disposal treatment. In this regard, to assure efficient water utilization by finding alternative water sources, sewage sludge collected from the wastewater treatment plant (WWTP) was recently investigated because it could represent a suitable resource for producing biomethane within the context of a circular economy. Therefore, this study aims at improving the current knowledge on the feasibility of biomethane production from sewage sludge by optimizing the logistic-supplying phase. In this regard, a GIS-based model was developed and applied to the Emilia-Romagna region to consider the existing networks of WWTPs and biogas systems to valorize sewage sludge for bioenergy production and minimizing environmental impact. The results of the GIS analyses allowed to localize the highest productive territorial areas and highlighted where sewage sludges are abundantly located and could be better exploited within agricultural biogas plants. Finally, the achieved results could help plan suitable policy interventions that are centered on biomass supply and outputs diversification, governance, and social participation, since the regulatory framework could play a crucial role in planning the reuse of these wastes for developing a more sustainable biomethane sector in line with the green economy goals.

Does the new-type urbanization construction improve the efficiency of agricultural green water utilization in the Yangtze River Economic Belt?

It is very important to control agricultural water pollution and promote agricultural water saving, for high-quality development of Yangtze River Economic Belt (YREB). The efficiency of agricultural green water utilization (EAGWU) needs financial and technical support from the new-type urbanization, which also change agricultural production mode and resource utilization level. This paper introduces non-point source water pollution into the output, adopts the super efficiency-slack model (SE-SBM) to measure the EAGWU, and uses difference generalized method of moments (DIF-GMM) to examine how new-type urbanization affects EAGWU from its four core characteristics. The results of EAGWU show that the overall efficiency value has been increasing rapidly in the research period, while the eastern provinces performed better and the central provinces performed worse. On the other hand, the overall difference in EAGWU first diverged and then shrunk, while economically developed provinces has been converging all the time. The results of driving factor estimation show that population urbanization has a significantly positive effect on EAGWU, with the rural labor force transfer and agricultural land circulation. Economic urbanization and urban-rural integration have negative effects, with the widening gap of absolute income and the compressed space of agricultural development. The EAGWU lag phase has a positive effect, because of the ratchet or cumulative effect, while equilibrium-urbanization has an insignificant effect. The conclusions will provide preferable recommendations for decision-making of green and water-saving development in agriculture.

Research on the impact of environmental regulation on water resources utilization efficiency in China based on the SYS-GMM model

Abstract The paper uses the super-efficiency data envelopment analysis (DEA) model to measure the water resources utilization efficiency of 30 provinces in China, and then uses the system generalized method of moments (GMM) model to analyze the impact of environmental regulations on China's regional water resources utilization efficiency. Conclusions as follows. (1) The overall water utilization efficiency is low, and the regions are very unbalanced. The more efficient areas are concentrated in the east, and the less efficient areas are in the west. (2) There is a ‘U’-shaped relationship between the intensity of environmental regulation and water resource utilization efficiency, that is, weaker environmental regulation intensity is not conducive to the improvement of water resource utilization efficiency, but when the intensity of environmental regulation crosses the ‘inflection point’, it can promote the improvement of water resources utilization efficiency. (3) The level of economic development has a very significant positive effect on water resources utilization efficiency, and the coefficient of scientific and technological progress is positive, but the impact of scientific and technological input on water resources utilization efficiency is limited and not significant; industrial structure and water resource utilization efficiency shows a negative correlation; water use structure and water resources efficiency show a negative correlation.

Is the Water System Healthy in Urban Agglomerations? A Perspective from the Water Metabolism Network.

Urban agglomerations are a primary spatial focus of socioeconomic activity and inherently include large volumes of embodied water. We have applied the concept of water metabolism health to comprehensively evaluate the overall operation of water systems in urban agglomerations and propose an innovative assessment framework. In particular, we constructed a water metabolism network (WMN) model to simulate a water system in which different cities and sectors are integrated, combining a newly compiled multiregional input-output (MRIO) table of water flow with ecological network analysis (ENA). A case study considering the Pearl River Delta (PRD) urban agglomeration in 2015 demonstrates that its network is well synergic but highly dependent, with considerable negative effects. Highly developed cities in southeastern of the PRD exhibit higher embodied water productivity and robustness but impose considerable negative effects on the water system. We found the agricultural sector to be a dominant controller of the network; the construction and service sectors represent the primary beneficiaries with strong competition. We suggest measures at various scales to improve water utilization efficiency and promote positive interactions between components, thus improving water metabolism system health for urban agglomerations.

Application of Rough Set and Neural Network in Water Energy Utilization

In water energy utilization, the damage of fault occurring in the power unit operational process to equipment directly affects the safety of the unit and efficiency of water power conversion and utilization, so fault diagnosis of water power unit equipment is especially important. This work combines a rough set and artificial neural network and uses it in fault diagnosis of hydraulic turbine conversion, puts forward rough set theory based on the tolerance relation and defines similarity relation between samples for the decision-making system whose attribute values are consecutive real numbers, and provides an attribute-reducing algorithm by making use of the condition that approximation classified quality will not change. The diagnostic rate of artificial neural networks based on a rough set is higher than that of the general three-layer back-propagation(BP) neural network, and the training time is also shortened. But, the network topology of an adaptive neural-fuzzy inference system is simpler than that of a neural network based on the rough set, the diagnostic accuracy is also higher, and the training time required under the same error condition is shorter. This algorithm processes consecutive failure data of the hydraulic turbine set, which has avoided data discretization, and this indicates that the algorithm is effective and reliable.