Waste Of Water Resources Research Articles

Effects of Biochar Application and Irrigation Methods on Soil Temperature in Farmland

Soil temperature plays a vital role in determining crop yield. Excessive irrigation may result in low soil temperature and a waste of water resources. In this paper, field experiments were carried out to evaluate the influence of irrigation methods and biochar application on soil temperature. The experiment included six treatments: (a) YB: biochar application in border irrigation with Yellow River water; (b) GB: biochar application in border irrigation with groundwater; (c) DB: biochar application in drip irrigation with groundwater; (d) Y(CK): border irrigation with Yellow River water; (e) G(CK): border irrigation with groundwater; (f) D(CK): drip irrigation with groundwater. The results are as follows: coupling drip irrigation and biochar, soil temperature increased by 1.20–3.87%. In the biochar application in border irrigation with Yellow River water and groundwater, soil temperature increased by 0.80–2.40% and 1.01–5.15%, respectively. Biochar is a medium for reducing the heat exchange of soil and atmosphere, as it hinders bi-directional heat movement. This mechanism was especially apparent at a 0–10 cm soil depth in the treatments of border irrigation using Yellow River water and groundwater. Biochar may help stabilize the fluctuation of soil temperature and improve the soil accumulated temperature. The effect of drip irrigation at 5–10 cm depth, border irrigation using the groundwater and the Yellow River water was great on soil temperatures above the 10 cm level but less on deep soil temperatures. After applying biochar to soil, the soil temperature was more sensitive to external temperature changes, such as air temperature and water temperature. Therefore, in the Hetao irrigation area, applying a proper amount of biochar to farmland soil was shown to improve the water and heat environment and improve the effectiveness of traditional border irrigation in synchronizing water and heat, especially under the drip irrigation condition. The results here suggest that using biochar under drip irrigation can promote growth and increase yield.

Research on Rational Utilization of Urban Water Resources Based on Sponge City Theory-Making Comparison between China and Singapore

Water resources are indispensable for human survival and production activities, but the world’s per capita sharing of water resources are not optimistic. With the acceleration of social development and industrialization, people pay more attention to economic development than the protection of water resources. Water pollution and waste have also worsened the issue of water scarcity. China, as the most populous country in the world, is particularly struggling for water shortage. Therefore, the research on the rational use of water resources is of great significance to China’s sustainable and healthy development. This paper analyzes the difficulties of water resources utilization and the issue of under-utilization of domestic water resources in China. It then accordingly proposes recommendations by comparing the current situation of sponge city construction at home and abroad. It is found that we are now facing the difficulties of water shortages, water resources waste and pollution in China on water use. What’s more, the fact that sponge city construction is mainly carried out in emerging cities indicates that we can learn from the successful experience of other countries like Singapore to make overall planning for regions and by time according to the national condition of China. Specifically speaking, the problems concerning water resources in different cities will be solved based on their local conditions.

Leakage Identification in Water Distribution Networks with Error Tolerance Capability

Leakages in water distribution networks have caused considerable waste of water resources. Thus, this study proposes a novel method for hydraulically monitoring and identifying regions where leakages occur in near-real time. A large network is first divided into several identification regions. To exploit a strong constructive and discriminative power, sparse coding is used, thereby adaptively coding the information embedded in observed pressures efficiently and succinctly. And a linear classifier is trained to determine the most likely leakage regions. A benchmark case is presented in this study to demonstrate the effectiveness of the proposed method. Results indicate that the proposed method can identify leakage events with enhanced tolerance capability for measurement errors. The method is also partially effective for identifying two simultaneous leakages. Certain practical advice in balancing the number of sensors and regions is also discussed to enhance the application potential of this method.

Discussion on standardization and automatic flow measurement of U-shaped channel water

Abstract: In human life, water resources are inseparable. In recent years, China's population growth has accelerated, and the industrial level has been continuously improved, resulting in the rapid use and waste of water resources. The protection and rational distribution of water resources is the most pressing issue in China's water resources. At present, the water measuring facilities of the U-shaped channel mainly include a straight wall measuring pool, a parabolic throat measuring pool and a long throat measuring pool. In view of the problems in irrigation measurement, the empirical water measurement of basic open channel and automatic flow measurement system in irrigation district is summarized to improve the accuracy, fairness and rationality of water measurement, and promote irrigation district management to a higher level.

Criteria for the estimation of field capacity and their implications for the bucket type model

SummaryField capacity (FC) is crucial for modelling soil–plant–water dynamics with bucket‐type models, supporting prevention of environmental problems (e.g. chemical leaching to deeper layers and groundwater and waste of water resources). As FC measurement in situ is labour intensive, approaches for its estimation have been proposed. However, because they differ conceptually and are based on different assumptions, the response to an application (e.g. crop yield (CY) modelling) can be rather different. This study evaluated frequently used FC approaches in scenarios quantifying differences in behaviour of soil water and air retention, evapotranspiration (ET) and CY. Also, a soil texture‐based pedotransfer function (PTF) was compared with other methods. Six sites with different soil types and management practices from tropical and temperate climates were investigated. Field capacity was estimated based on a static criterion using the water content (θ) at pressure heads (h) of 0.6, 1 and 3.3 m and at the inflection point (θi) of all water retention curves (SWRCs) and the Assouline and Or model (AO). Moreover, four equations found in the literature based on a dynamic criterion were also evaluated. For all soils, the largest FC results were obtained when θi was set as FC. The smallest FC values were obtained with θ (3.3 m) (tropical) and AO (temperate). The coefficient of variation (CV) between FC estimates, based on nine approaches, ranged from 7 to 54%. Available water storage, air capacity (AC) and ET results were sensitive to FC and showed more variation for the Brazilian sites. The PTF used estimated FC within the range of results obtained by the other nine approaches. In addition, AquaCrop was used to study the effect of FC on CY by fixing all model parameters, whereas FC was the only flexible parameter. Crop yield was sensitive to the variation in FC under low and medium rainfall, but increased with larger FC. For high rainfall, the yield was small in a scenario with large θfc because AC became yield limiting.Highlights Different approaches can be used to estimate field capacity The criteria static and dynamic and a texture-based PTF were evaluated Sensitivity analyses were performed with parameters of bucket type model and crop yield simulations Results showed that management decisions differed according to field capacity criteria

Industrial Application of a Deep Purification Technology for Flue Gas Involving Phase-Transition Agglomeration and Dehumidification

Abstract A moist plume forms when the flue gas emitted from wet desulfurization equipment exits into the ambient air, resulting in a waste of water resources and visual pollution. In addition, sulfur trioxide (SO3), water with dissolved salts, and particles in the wet flue gas form secondary pollution in the surrounding atmosphere. In this study, a deep purification technology for flue gas involving phase-transition agglomeration and dehumidification (PAD) is proposed. This deep purification technology includes two technical routes: the integrated technology of phase-transition agglomeration and a wet electrostatic precipitator (PAW); and the integrated technology of phase-transition agglomeration and a mist eliminator (PAM). Industrial applications of PAW and PAM were carried out on 630 and 1000 MW coal-fired units, respectively. The results show that the average amount of recycled water obtained from wet flue gas by means of PAD is more than 4 g·(kg·°C)−1. Decreasing the wet flue gas temperature by 1.5–5.3 °C allows 5%–20% of the moisture in the flue gas to be recycled; therefore, this process could effectively save water resources and significantly reduce water vapor emissions. In addition, the moist plume is effectively eliminated. With the use of this process, the ion concentration in droplets of flue gas is decreased by more than 65%, the SO3 removal efficiency from flue gas is greater than 75%, and the removal efficiency of particulate matter is 92.53%.

Design of Remote Monitoring System of Irrigation based on GSM and ZigBee Technology

To solve the problems of low level of irrigation and waste of water resources, a remote monitoring system for farmland irrigation based on GSM communication technology and ZigBee technology was designed. The system is composed of sensors, GSM communication module, ZigBee module, host computer, valve and so on. The system detects and closes the pump and the electromagnetic valve according to the need of the system, and transmits the monitoring information to the host computer or the user’s Mobile phone through the GSM communication network. Experiments show that the system has low power consumption, friendly man-machine interface, convenient and simple. It can monitor agricultural environment remotely and control related irrigation equipment at any time and place, and can better meet the needs of remote monitoring of farmland irrigation.

Research Status of Evaporative Condenser

Reducing energy consumption, saving water resources, recycling cool water are main directions of China’s development. Evaporative condenser using latent heat reduces water resources waste, with energy-saving advantages. This paper reviews the research status of evaporative condenser at home and abroad, and introduces the principle, classification, various influencing factors of evaporative condenser, and puts forward the future research direction.

Study on Fluid-Rock Interaction and Reuse of Flowback Fluid for Gel Fracturing in Desert Area

Hydraulic fracturing requires a large volume of fresh water, which is difficult and expensive to obtain in the desert area such as Tarim Basin. Currently, flowback fluid is typically transported to the sewage treatment plant and then discharged after reaching environmental requirements; however, this is not only costly, but also a waste of water resource. Therefore, it is imperative to understand the potential interactions between fracturing fluid and reservoir rock, and then find solutions to reuse the flowback water for subsequent fracturing. In this study, once flowback fluid was directly collected from the field, its chemical compositions were analyzed; then, filtering, decoloring, and chelating methods were chosen to effectively remove or shield the unfavorable reintroduced components. Moreover, pH value was further tuned during different stages of the recycling process to ensure good gelation and cross-linking properties of guar. Cross-linked guar synthesized with the flowback fluid was evaluated in the lab through shear resistance tests and coreflood tests under the reservoir conditions; results indicated the recycled gel behaved similarly as the original gel, or even better. From this work, a cheap and effective treatment process was proposed to reuse the flowback fluid in the desert area.

Effects of probiotic addition on the growth performance, digestive enzyme activity, and intestinal morphology of gibel carp ( Carassius auratus gibelio ) cultured using biofloc technology

PDF HTML阅读 XML下载 导出引用 引用提醒 生物絮团养殖模式下益生菌添加对异育银鲫生长、消化酶活性及肠道组织结构的影响 DOI: 作者: 作者单位: 1. 大连海洋大学, 辽宁 大连 116023;2. 盐城工学院, 江苏 盐城 224051 作者简介: 徐晨(1993-),女,硕士研究生,从事水产养殖和病害防治研究.E-mail:2459137028@qq.com 通讯作者: 中图分类号: S963;Q96 基金项目: 江苏省自然科学基金项目（BK20150426）；国家自然科学基金项目（31602179）；江苏省博士后基金项目（1501101C）；盐城工学院人才引进项目（xj201513，kjc2014018）. Effects of probiotic addition on the growth performance, digestive enzyme activity, and intestinal morphology of gibel carp (Carassius auratus gibelio) cultured using biofloc technology Author: Affiliation: 1. Dalian Ocean University, Dalian 116023, China;2. Yancheng Institute of Technology, Yancheng 224051, China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:前期研究表明，生物絮团技术（biofloc technology，BFT）适于异育银鲫（）养殖。为进一步优化BFT养殖模式，本研究设置3个实验组：BFT模式下EM菌添加组（BB组）、枯草芽孢杆菌（）添加组（BI组）和BFT对照组（B组），以均体重（1.60±0.50）g的异育银鲫为研究对象，探讨BFT模式下外源添加益生菌对养殖动物生长、消化酶活性及肠道组织结构的影响。结果表明：（1）益生菌添加组异育银鲫增重率和特定生长率显著高于对照组（<0.05），BB和BI组的增重率分别提高了216.70%和184.04%，特定生长率分别提高了141.18%和125.49%，BB和BI组间差异不显著（<0.05）。益生菌添加组间，BB组淀粉酶活性显著高于BI组（>0.05）；（3）益生菌添加组肠道肌层厚度和黏膜下层厚度显著高于对照组（B组）（>0.05）。研究表明，BFT养殖模式下外源添加益生菌可以更好地促进异育银鲫生长。 Abstract:Probiotics have been defined as live microorganisms, which confer health benefits to the host when administered in adequate amounts. The probiotics used in aquaculture commonly include effective microorganisms (EM bacteria), sp. The biofloc technology (BFT) is a zero-water exchange and eco-friendly aquaculture system. The BFT can recycle nutrient by introducing additional carbon source to culture water in order to stimulate the growth of heterotrophic bacteria that convert ammonia into microbial biomass. The microbial biomass will further aggregate with other microorganisms and particles to form bioflocs. The bioflocs contain a heterogeneous mixture of diatoms, macroalgae, food and fecal remnants, exoskeletons, bacteria, invertebrates, and other microorganisms. The bioflocs can maintain good water quality, increase fish growth performance, reduce feed cost by recycling feed residues and fecal excrements, aid enzymatic activity, and enhance innate immunity and disease resistance. Meanwhile, the BFT can minimize water exchange to save labor and environmental costs, and reduce water usage and waste generated in aquaculture. It can also avoid drug abuse for disease control, because of the key microorganism in the bioflocs. The BFT has the potential to be used widely in aquaculture. Gibel carp () is one of important freshwater species farmed in China, and it is a representative species of mudflat cultured fish. However, with the rapid development of aquaculture, the waste of water resources, pollution, and diseases seriously affected the sustainable development and aquaculture efficiency of gibel carp. Our previous studies showed that the BFT can be used in gibel carp culture and that it has positive effects on the growth performance and immune response of gibel carp. To further optimize the BFT system in gibel carp culture, a 35-day feeding experiment was conducted to evaluate the effects of probiotics on the growth performance, digestive enzyme activities, and intestinal morphology of gibel carp cultured using the BFT. A total of 1800 normal gibel carps with a mean body weight of 1.60 g were randomly assigned to nine ponds (3.0 m×1.0 m×0.8 m) as three experimental treatments, including the EM bacteria addition group in BFT system (BB), s addition group in BFT system (BI), and BFT without any probiotics addition (B). The results revealed the followings (1) Compared with those of the control group, weight gain and specific growth of gibel carp in the BB and BI groups were significantly higher (<0.05); the weight gain in the BB and BI groups increased by 216.70% and 184.04%, respectively. Furthermore, the specific growth increased by 141.18% and 125.49%, respectively. The weight gain and specific growth in BB group were higher but no significantly different from those in BI group (>0.05). These results indicate that the addition of probiotics to BFT system can promote the growth of gibel carp. Additionally, compound bacteria (EM bacteria) addition showed better efficiency than the addition of single strain . (2) The activity of digestive enzymes (amylase, lipase and protease) in the probiotics addition groups (BB and BI) was significantly higher than those in control group (<0.05), and the highest activities were observed in BB group. The activity of amylase in BB group was significantly higher than that in BI group (<0.05). (3) The thickness of muscularis and submucosa of gibel carp gut in the probiotics addition groups was significantly higher than those in control group (<0.05). The mucosal fold height and fold mesenchyme width of gibel carp gut were not significantly different among the BB, BI, and control groups (>0.05). The results suggest that the addition of probiotics can promote growth of gibel carp and improve their intestinal digestive enzyme activities. Furthermore, the addition of probiotics can also affect the intestinal morphology of gibel carp cultured in BFT system. This study provides some valuable information to promote the usage of BFT in aquaculture. 参考文献 相似文献 引证文献

The Comparison and Experiential Learning in the Metropolitan Delta

Throughout the history of the world, the development of cities is inseparable from the large water system and the ocean. The world-class urban agglomerations are concentrated on the delta metropolitans that water-affluent areas. Since ancient times, the whole world has commonness in delta`s development. Since the 1980s, the massive processes featuring the typical Time-Space compression, enhance complicated conflicts in China`s daily life. The enormous floods of the global climate change, soil erosion, environmental pollution, water resources waste, and the loss of hydrology landscape also affect the urban development. As a result the Chinese government has induced the “New urbanization”, “Sponge City- project” and so forth, Scientific urbanization and sustainable ecological urban planning gain wide attention. This paper will focus on the urban development of the Delta metropolitans. The methods of literature research, re-mapping, case sudy, comparative study, multi-perspective study will be applied in this paper. It will take the Yangtze River Delta and Euro Delta as examples, compare the similarities and differences of these two deltas in perspective of urban morphology and delta governance. The aspects of urban morphology contains city site selection, urban form and urban elements, the cores evolution and historical superposition of urban agglomeration. Actor, factor, institution, as the city gene leave their traces on the urban fabric. The paper also learns the experiences of water management and city-group development from both deltas. The Yangtze River Delta could learn from the Euro Delta in terms of the urban revitalization and the reconstruction of waterfront areas. In conclusion, it will give suggestions for future`s urban resilience development.

The remote farmland environment monitoring system based on ZigBee sensor network

In order to change the traditional management of agricultural production, ZigBee technology is used in short distance wireless transmission to design intelligent farmland environment remote monitoring system, which integrates communication, computer and all aspects of network technology. The real-time, accurate data collection of farmland soil pH value, the temperature and humidity surroundings of the plants, illumination intensity and crop chlorophyll content, all will provide reliable data for intelligent agricultural production, thereby, the level of intelligence of agricultural management is increased. Based on precision guidance, irrigation will become intelligent which can avoid the waste of water resources and low utilisation rate caused by free operation. At the same time, it will promote modernisation of agricultural production process.

Research on Leak Detection of Water Pipeline Base on PSO-SVM

Leakage of water supply pipeline will cause waste of water resources and economic losses, the traditional support vector machine (SVM) had two free parameters (include kernel parameter g and penalty factor C from the radial basis function kernel) which could lead the classifier in an instability situation. In this paper, a method was presented to establish a SVM model which used the particle swarm optimization algorithm (PSO) to determine the two unknown parameters. Particle swarm optimization is an intelligent computational swarm optimization method, which optimizes a problem by iteratively trying to improve a candidate solution with regard to a given measure of quality. The method not only has strong global search capability, but also easily to implement. In order to improve the accuracy of the SVM model, the PSO algorithm is used to optimize the parameters of SVM. A prediction model of water pipeline leak detection based on PSO-SVM is established after the sample set is been collected, trained, tested and classified. The experimental results showed that with the strong global search capability of PSO, the free parameters of SVM was been set effectively and accuracy of the classifier had been promoted.

Sustainable Planning of City Water System—Study on Water Supply, Drainage, Water Treatment and Reuse

The rapid development of China's economy has lead to the excessive use and serious pollution of water resources in China. The underground water and ground water have been polluted in vary degrees. In order to alleviate the decrease of water resources and pollution condition in China, this paper explores the effective methods to build sustainable city water system: Firstly, taking the residential area as a unit and improving facilities construction of city water supply engineering to reduce the waste of water resources and improve the utilization of water resources; Secondly, making full use of unconventional water resources and improving the traditional water treatment process; Thirdly, making the water supply, water drainage, water treatment and reuse form a complete water recycling system. Finally, the paper discusses a comprehensive elaboration though an actual project.

The Feasibility on the Case that the Air Conditioning Condensate Water is used as the Make-up Water of Cooling Tower

The cooling water consumption accounts for 80% of total industrial water consumption. The cooling water need be used more reasonably, while waste of water resources may be reduced by minimizing water losses and recycling these resources. It is hard to collect condensate due to the low yield, but there are major advantages. An integrated service building of Beijing is employed as the example, condensate yield and water-saving amount are calculated according to central air conditioning systems and fan coil units. In addition, the feasibility of supplying condensate from air conditioners to cooling towers is comprehensively analyzed based on construction budgets. Results suggest that it is energy-efficient and feasible to recycle and reuse the condensate, which is a by-product of central air-conditioners.

Enhancements in ElectroKinetic Remediation Technology: Focus on water management and wastewater recovery

The ElectroKinetic Remediation Technology (EKRT), when applied to an earthy matrix, is generally targeted to the extraction of one or more pollutants, often inorganic and typically belonging to the category of heavy metals. The technique exploits the effects caused by the application of an electric field for allowing the mobilization of the targeted pollutants, whose displacement is often facilitated by the use of suitable chemicals, which act as complexing agents. The EKRT represents a very promising approach, as it is able to produce results comparable to those of other on/off-site interventions, though with appreciably higher levels of acceptability. Moreover, in spite of expectations (which are substantially based on the high use of energy and consumables), we showed that, once properly configured, the EKRT may represent an excellent choice even when judged based on the environmental sustainability. With the present study, we aim at discussing further the plant configuration, with a special focus on the water management. In fact, as anticipated in our previous communications, the modifications that we implemented in our EKRT approach allow presenting it as an electrochemically-assisted soil flushing. Several are the elements of innovation introduced, which proved to increase the effectiveness of the remediation, but at the price of a potentially very high water (and energy) consumption. It is therefore important to have an advanced water management system, preferably coupled with a reliable wastewater recovery system in order to avoid the waste of water resources, and consequently keep down costs as well as the ecological footprint related with the implementation of this technology, thus maximizing its benefits.

A Comprehensive Quantitative Evaluation of New Sustainable Urbanization Level in 20 Chinese Urban Agglomerations

On 16 March 2014, the State Council of China launched its first urbanization planning initiative dubbed “National New Urbanization Planning (2014–2020)” (NNUP). NNUP put forward 20 urban agglomerations and a sustainable development approach aiming to transform traditional Chinese urbanization to sustainable new urbanization. This study quantitatively evaluates the level of sustainability of the present new urbanization process in 20 Chinese urban agglomerations and provides some positive suggestions for the achievement of sustainable new urbanization. A three-level index system which is based on six fundamental elements in a city and a Full Permutation Polygon Synthetic Indicator evaluation method are adopted. The results show that China is undergoing a new urbanization process with a low level of sustainability and there are many problems remaining from traditional urbanization processes. There exists a polarized phenomenon in the urbanization of 20 urban agglomerations. Based on their own development patterns, the 20 urban agglomerations can be divided into seven categories. Every category has its own development characteristics. The analyses also show that waste of water resources, abuse of land resources, and air pollution are three big problems that are closely linked to traditional Chinese urbanization processes. To achieve sustainable new urbanization in China, four relevant suggestions and comments have been provided.

The remote farmland environment monitoring system based on ZigBee sensor network

In order to change the traditional management of agricultural production, ZigBee technology is used in short distance wireless transmission to design intelligent farmland environment remote monitoring system, which integrates communication, computer and all aspects of network technology. The real-time, accurate data collection of farmland soil pH value, the temperature and humidity surroundings of the plants, illumination intensity and crop chlorophyll content, all will provide reliable data for intelligent agricultural production, thereby, the level of intelligence of agricultural management is increased. Based on precision guidance, irrigation will become intelligent which can avoid the waste of water resources and low utilisation rate caused by free operation. At the same time, it will promote modernisation of agricultural production process.

Experimental study on the impact of mass moisture content on the evaporative cooling effect of porous face brick

Porous face bricks on the outside of a building wall exhibit evaporative cooling after absorbing water. Thus, these bricks are promising for use as a passive energy-saving building technology. Artificial watering is an effective method to ensure a sufficient water supply for effective evaporative cooling. However, improper watering measures may result in the waste of water resources while failing to achieve the evaporative cooling effect. In this paper, studies were conducted on a composite wall composed of a facing layer and a base layer as follows. (1) The mass moisture content variations in the porous face brick with respect to soaking time were measured, and the feasibility of using this type of face brick as an evaporative cooling carrier was investigated. (2) The relationship between mass moisture content and the evaporation capacity of the porous face brick was determined under stable conditions. A critical mass moisture content for the porous face brick was determined through analysis of the measurement data. (3) A field measurement was performed to verify the feasibility of using the critical mass moisture content as a criterion for watering. The results indicate that the temperature and heat flows at the inner and outer surfaces of the composite wall were reduced significantly. However, when the mass moisture content exceeded the critical mass moisture content, the evaporative cooling capability tended to stabilize with further watering. Therefore, the critical mass moisture content of the porous face brick can be used as a criterion for watering to conserve water while facilitating the evaporative cooling effect.

Research on recognition of coal and gangue based on image processing

In order to avoid the waste of water resources and environmental pollution caused by separating coal and gangue in the traditional methods, a novel method based on image processing is proposed in this paper. Firstly the image of coal or gangue is preprocessed. Then the mean value of gray histogram is extracted which serves as the statistical feature value to initially recognize coal and gangue. Then the textural feature is extracted from the image which is based on an adaptive window of texture analysis. The adaptive window size is determined by the contrast texture feature parameter. The adaptive window of texture analysis can improve the discriminability of coal and gangue. This method not only considers the image’s gray feature but also utilizes the image’s spatial information, so the recognition precision is improved. This method provides new ideas for dry separation technology.