A model of fuzzy comprehensive evaluation for water saving irrigation system (WSIS) decision making is proposed based on establishing an index system affected by six kinds of basic factors including qualitative and qu...A model of fuzzy comprehensive evaluation for water saving irrigation system (WSIS) decision making is proposed based on establishing an index system affected by six kinds of basic factors including qualitative and quantitative indexes. The object function of WSIS is set up by using the concept of fuzzy membership degree, it is to transform characteristic vector matrix into unify membership matrix and extending the least square method to the least of weighted distance square. The optimum weighted membership degree and the inferior weighted membership degree are used to solve the object function. This method effective solves the problem of classify for fuzzy attributive indexes and the problem of optimum for the set of different attributive indexes. A case study shows that the fuzzy comprehensive evaluation model is reasonable and effective in decision making for water saving irrigation system planning.展开更多
Evaporation loss from the saturated soil beneath drip irrigation emitters highly influences the irrigation efficiency of drip krigation (D1]. Subsurface drip irrigation (SDI) is one good approach to curb this ineff...Evaporation loss from the saturated soil beneath drip irrigation emitters highly influences the irrigation efficiency of drip krigation (D1]. Subsurface drip irrigation (SDI) is one good approach to curb this inefficiency, but in a new irrigation method, straight tube irrigation (STI), the irrigation tubes do not need to be buried and thus STI is recommended to increase the irrigation efficiency under normal surface-applied DI. STI consists of only connectors and water-transference tubes that can directly transfer irrigation water from the lateral emitters in the drip line to the root zone of plants. Five-month field experiments were carried out in aeolian sand soil in the forest-belts of the Taklimakan Desert, which have poor water storage capacity, to compare the potential water saving between STI and DI. The preliminary results showed that, compared with DI, STI (1) improved the soil water content in soil depths from 40 to 100 cm under the soil surface; (2) achieved the same irrigation effects in relatively shorter irrigation durations; (3) had very little water loss due to deep seepage; and (4) formed a layer of dry sand about 10 to 30 cm thick immediately below the soil surface, which lessened evaporation loss of soil water beneath the emitters on the soil surface. This demonstrates that STI can maximize the water-saving potential of DI through the reduction of wetted soil perimeters on the soil surface. This is valuable information for water-saving engineering applications and projects with STI in arid and semiarid regions.展开更多
Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is base...Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is based on the matter-element analysis and combined with the concepts of fuzzy mathematics,which is called the method of fuzzy matter-element analysis.It constructs the compound fuzzy matter element with the investment projects,evaluation factors and their fuzzy value.Through establishing the best subjection degree (fuzzy value),complex fuzzy matter element of relational coefficient and weight aggregation of fuzzy matter-element model,the writer achieves on optimum order of the investment projects according to the calculated relational degree and finds the best project.In this paper,the calculation of weight adopts the analytical hierarchy process method(AHP).Through the actual example,it shows that the model is simple and its calculation is reliable.It is very significant for the engineering evaluated bid and investment decision.展开更多
Water is the source of all the creatures on the earth and energy is the main factor driving the world. With the increasing population and global change, water and energy conservation have become worldwide focal issues...Water is the source of all the creatures on the earth and energy is the main factor driving the world. With the increasing population and global change, water and energy conservation have become worldwide focal issues, particularly in the water-stressed and energy-limited regions. Rainwater harvesting, based on the collection and storage of rainfall runoff, has been widely used for domestic use and agricultural production in arid and semiarid regions. It has advantages of simple operation, high adaption, low cost and less energy consumption. This study reviewed rainwater harvesting systems adopted in the Loess Plateau of China and analyzed water use efficiency (WUE) for various rainwater harvesting techniques. Supplemental irrigation using harvested rainwater could increase crop yield by more than 30%, and WUE ranged from 0.7 to 5.7 kg m4 for spring wheat, corn and flax, and 30-40 kg m-3 for vegetables. Moreover, energy consumption for rainwater harvesting based on single family was compared with traditional water supply in the city of the Loess Plateau using the life cycle assessment (LCA) method. Results showed that energy consumption yielded per unit harvested rainwater was 25.96 MJ m-3 yr which was much less than 62.25 MJ m3 yr^-1 for main water supply in Baoji City, Shanxi Province, meaning that rainwater harvesting saved energy by 139.8% as compared to the main water supply system. This study highlights the importance and potential of rainwater harvesting for water and energy conservation in the near future.展开更多
Through applying PPE model based on RAGA to evaluate the benefit of rice water saving,the author turns multi-dimension data into low dimension space.So the optimum projection direction can stand for the best influence...Through applying PPE model based on RAGA to evaluate the benefit of rice water saving,the author turns multi-dimension data into low dimension space.So the optimum projection direction can stand for the best influence on the collectivity.Thus,the value of projection function can evaluate each item good or not.The PPE model can avoid jamming of weight matrix in the method of fuzzy synthesize judgement,and obtain better result.The author wants to provide a new method and thought for readers who are engaged in investment decision-making of water saving irrigation and other relative study.展开更多
Drip irrigation system can achieve high uniformity. When the system is designed for uniformity coefficient equal or more than 70%, the water application in the field can be expressed as a normal distribution and furth...Drip irrigation system can achieve high uniformity. When the system is designed for uniformity coefficient equal or more than 70%, the water application in the field can be expressed as a normal distribution and further simplified to a linear distribution. This paper will describe the irrigation scheduling parameters, percent of deficit, application efficiency and coefficient of variation by simple mathematical model. Using this effective model and the irrigation application, the total yield affected by the total water application for different uniformity of irrigation application can be determined. More over, this paper uses the cost of water, price of yield, uniformity of the drip irrigation system, crop response to water application and environmental concerns of pollution and contamination to determine the optimal irrigation schedule. A case study shows that the optimal irrigation schedule can achieve the effect of water saving and production increment compared with the conventional irrigation schedule in which the whole field is fully irrigated. Key words drip irrigation - linear cumulative frequency curve - optimal irrigation schedule - water saving - production increment CLC number TV 139.1 Foundation item: Supported by the National Natural Science Foundation of China (59379407)Biography: QIU Yuan-feng (1973-), male, Ph. D, research direction: water saving irrigation theory and techniques.展开更多
Irrigation water supply is one of the vital components for sustainable rice farming, which is becoming a limiting resource in the changing climatic condition. An experiment was conducted at the research field of Bangl...Irrigation water supply is one of the vital components for sustainable rice farming, which is becoming a limiting resource in the changing climatic condition. An experiment was conducted at the research field of Bangladesh Agricultural University, Mymensingh during dry season from January-June of 2017 to investigate the suitability of Alternate Wet and Dry Irrigation (AWDI) for sustainable rice production and reducing methane emission. The modern rice variety BINA Dhan 10 was used as test crop. There were five irrigation treatments viz. T<sub>1</sub> (saturated condition), T<sub>2</sub> (continuous flooded, 5 cm standing water), T<sub>3</sub> (AWDI-10 cm;irrigated when water level fell 10 cm from surface), T<sub>4</sub> (AWDI-15 cm;irrigated when water level fell 15 cm from surface) and T<sub>5</sub> (AWDI-20 cm;irrigated when water level fell 20 cm from surface). Results of the field trial showed satisfactory grain yield and low seasonal methane emission along with significantly high irrigation water savings (%) in AWDI treated field plots. Among the treatments, T<sub>3</sub> (AWDI-10 cm) and T<sub>4</sub> (AWDI-15 cm) showed higher yield performance (6250kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#f7f7f7;"=""><sup>.</sup></span>ha<span style="color:#FFFFFF;font-family:" white-space:normal;background-color:#d46399;"=""><span style="color: rgb(79, 79, 79);" font-size:14px;white-space:normal;background-color:#ffffff;"=""><sup>-</sup></span></span><sup>1</sup> and 5810 kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#f7f7f7;"=""><sup>.</sup></span>ha<sup><span style="white-space:nowrap;">-</span>1</sup>, respectively) with lower CH<sub>4</sub> emission (reduced up to 36% and 40%, respectively) compared to continuous flooded treatment (T2, CF 5 cm water). In AWDI field plots less irrigation frequency (6 - 9) was required which significantly saved the amount of irrigation water (12% - 24%). Although T<sub>5</sub> (AWDI-20 cm) showed the highest water savings (24%) and lowest CH<sub>4</sub> emission (reduced up to 50%);however the lowest grain yield (4283 kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#f7f7f7;"=""><sup>.</sup></span>ha<span style="color: rgb(79, 79, 79);" font-size:14px;white-space:normal;background-color:#ffffff;"=""><sup>-</sup></span><sup>1</sup>) was found under this treatment. On the other hand, continuously irrigated (T2, 5 cm standing water) field plot showed lower yield (4783 kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#f7f7f7;"=""><sup>.</sup></span>ha<sup><span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#ffffff;"="">-</span>1</sup>) but significantly higher methane emissions compared to other treatments during rice cultivation. Water productivity index was also found higher in AWDI treated field plots compared to continuously irrigated field plot. At the reproductive stage of rice plant well-developed aerenchyma tissue was observed in root cortex under the continuous irrigated field plot, which indicates higher diffusion pathway of methane gas from root rhizosphere to the atmosphere compared to other treatments. Therefore, alternate wet and dry irrigation water management practice may be recommended at farmers’ level for sustainable rice production and reducing methane emission during dry winter Boro season which will reduce the cost of production by water saving as well as energy saving.展开更多
With the development of the production scale and the increasing of the process technologies and facilities,product quality and the requirement of water supply continuously put forward new requirements to water treatme...With the development of the production scale and the increasing of the process technologies and facilities,product quality and the requirement of water supply continuously put forward new requirements to water treatment technology.The practice of the water saving technology should ensure the safe of water using and the innovation of technique data.Especially the stabilization of water quality should also meet the production at full capacity,reduce equipment failure rate and maintain the sustainable development under the condition of the minimal resource consumption.This article describes the practice of Baosteel saving technology,water-saving ideas from the system to start,according to Baosteel raw water intake requirements and process water and drainage characteristics,water and salt water tidal according to changes in the Yangtze River and the Yangtze River upstream and downstream trends in water discharge on water quality factors,established the electrical conductivity,chloride ion indicators for the control of the Yangtze River water,the implementation of 'avoid salt build light' water at the same time,combined with the actual situation of water pollution in the Yangtze River,the use of force coefficient correlation theory,the implementation of 'avoid taking clear pollution' to ensure the quality of raw water intake. System and cascade utilization of water,process water,based on whole plant water balance testing, analysis,technical parameters of the system and processes the user running the pressure balance pipe network,and implemented a stabilization system to adjust water pressure,reducing the water supply network systemwater loss;application of electrochemical principles,the implementation of the protection of underground pipes Baosteel,implemented a water use,steps to use,the operating mode of water supply in series to increase water reuse,reduce wastewater discharge system. Water quality stability and water-saving in the process;carry out water quality stability technology in the different complicated processes of the steel industry;apply the environmental protection and water quality, sterilization,non-phosphorus and low phosphorus technologies which are suitable for high concentration of circulating water.By these technologies,we achieved the water-saving in the process in different seasons and solved the technical problems affecting production such as equipment corrosion,scaling and the formation of the water quality proprietary technology under the conditions of high heat load production as well. The use of water ecological conservation and biological treatment technology:the implementation of the reservoir to the ecological technology is characterized by food chain and wetland environmental technology characterized by plants chain.Reservoir ecological management techniques in the use of natural conditions, wind direction,temperature,light and fish biomass in the reservoir water level regulation of balance and combination of organic,control and resolve the reservoirs in spring and summer algae problems and water quality changes rot of the 'fresh' operating problems.The artificial wetland technology develops a new way for metallurgical plants' wastewater treatment.All the measures by the implementation of water to create the conditions for the system to achieve the water target of constant innovation,reaching the advanced level of iron and steel enterprises.展开更多
The development of water-saving agriculture is of great significance not only for increasing farmers’ production and income, but also for protecting water resources. The purpose of this paper is to learn from the exp...The development of water-saving agriculture is of great significance not only for increasing farmers’ production and income, but also for protecting water resources. The purpose of this paper is to learn from the experience of Israel, Japan, Korea and Singapore, improve the low efficiency of agricultural water use in China, and solve the problem of water shortage, promote the development of agriculture. This article concludes that the experience of water-saving agriculture in Israel is advanced irrigation technology, sound laws and regulations, and emphasis on science and technology. Japan’s water-saving agriculture is characterized by an efficient irrigation program and a strict agricultural water management policy. Korea’s experience in water-saving agriculture is that it has a strict water management system, with the government subsidizing the cost of irrigation projects and integrating water into agricultural development planning. Singapore’s experience in water-saving agriculture is to raise awareness of water conservation and to use step water prices. In order to promote the sustainable development of water-saving agriculture in China, the research on water-saving agriculture in the future can be carried out from the aspects of agricultural production or related agricultural technology.展开更多
This paper is concerned with water saving for water-loop cooling tower system in power plants. A newly developed water saving device of swirling flow is presented. The key point is that the new water saving device mak...This paper is concerned with water saving for water-loop cooling tower system in power plants. A newly developed water saving device of swirling flow is presented. The key point is that the new water saving device makes the steam swirl up along the device wall rather than engender laminar flow in a corrugated plate. The corrugated plate device can save approximately 10 percent of the total lost water. In contrast to the scale model of corrugated plate water saving device, experimental analyses have demonstrated that the new water saving device of swirling flow is more efficient, with a capacity of saving more than 20 percent of water.展开更多
Jointly hosted by the Standardization Administration of China (SAC) and the National Development and Reform Commission, the Meeting for Promotion of the Standards for Water Saving was held in Beijing on Oct. 5th, 2004...Jointly hosted by the Standardization Administration of China (SAC) and the National Development and Reform Commission, the Meeting for Promotion of the Standards for Water Saving was held in Beijing on Oct. 5th, 2004, with the aim of promoting development of water intake technology, improving efficiency of water using and developing recycle economy. The meeting analyzed the current展开更多
Agricultural irrigation is a primary user for freshwater withdrawal. Irrigation plays an important role in crop production, as it provides the benefit of reducing the effects of prolonged dryness and erratic precipita...Agricultural irrigation is a primary user for freshwater withdrawal. Irrigation plays an important role in crop production, as it provides the benefit of reducing the effects of prolonged dryness and erratic precipitation. Center pivot irrigation system is the most common irrigation system in agriculture. As the center pivot irrigation system ages, the system could develop a leaking joint, clogged sprinklers, and physical damage. This can cause areas of non-uniformity that can lead to under- or over-irrigated in some areas of the land, resulting in excess energy use and cost, wasting resources, and environmental impacts. Thus, it is important to evaluate the performance of a center pivot irrigation system regularly to maximize return on investments and minimize wasting resources. This study focuses on evaluating the impacts and benefits of improved center pivot irrigation distribution uniformity by performing distribution uniformity evaluations pre- and post-retrofit. This study also focused on demonstrating an unmanned aerial vehicle (UAV) to assess the performance of the center pivot irrigation system in two irrigated farmlands. The Coefficient of Uniformity (CU), Distribution Uniformity (DU), and Scheduling Coefficient (SC) were calculated based on the catch can test data. The values were utilized to evaluate water and energy savings from the improved coefficients. The team has found that replacing sprinkler packages increased the CU from 78 to 89 and the DU from 77 to 82, and reduced the SC from 1.3 to 1.2 in Field A. In Field B, replacing sprinkler packages increased the CU from 73 to 91 and the DU from 62 to 84 and reduced the SC from 1.6 to 1.2. The estimated water savings in Field A due to the reduced scheduling coefficient was approximately 151,000 liters/hectare/year, with consideration of the corn and soybean rotation field in Michigan. The estimated water savings in Field B was 608,000 liters/hectare/year. The data from this demonstration study showed the value of distribution uniformity evaluation and retrofit of irrigation systems. This information will encourage farmers and agricultural industries to consider performing more distribution uniformity evaluations, ultimately improving irrigation water use efficiency and supporting sustainable water management in agriculture.展开更多
In an effort to save the precious water resource and reduce the environmental impact, Fong’s Industries Group along with its member companies, namely "Fong’s National", "THEN", "Goller"...In an effort to save the precious water resource and reduce the environmental impact, Fong’s Industries Group along with its member companies, namely "Fong’s National", "THEN", "Goller" and "Fong’s Water Technology" provide an ecological dyeing solution to reduce the water consumption drastically through their innovative technologies covering the processes from yarn dyeing to piece dyeing and recycling of discharge after dyeing and finishing.展开更多
AMONG the chain of lakes on the bottom of the western Great Rift Valley, Lake Tanganyika stands out for its extraordinary north-south extension and depth. With its large size and high biodiversity, Lake Tanganyika is ...AMONG the chain of lakes on the bottom of the western Great Rift Valley, Lake Tanganyika stands out for its extraordinary north-south extension and depth. With its large size and high biodiversity, Lake Tanganyika is of great social, economic, political and environmental significance to neighboring countries. However, the water quality of the lake is on the decline due to the mounting environmental chal- lenges it faces. Chinese scientists under the UNEP-China-Africa Cooperation Program on Environment are working closely with African partners to find out the sources of the pollution and possible solutions with a focus on water quality monitoring and treatment.展开更多
The most restrictive factor in the way of economic prosperity in China’s northwest lies in the lack of water resources.To seek countermeasures against this ages-old scourge of the arid hinterland,the CAS Division of ...The most restrictive factor in the way of economic prosperity in China’s northwest lies in the lack of water resources.To seek countermeasures against this ages-old scourge of the arid hinterland,the CAS Division of Earth Sciences sponsored a workshop in Beijing on tapping water resources of Chinese northwest in March 1995 and decided to organize an expedition team of CAS members to investigate the water resources there.From August 23 to September 5,1995,the team carried out an on-the-spot survey along a 3,000-kilometre-long itiner-展开更多
Water is the source of life,the soul of cities,the keyof agriculture,and the blood of industry.Nobody can livewithout water,and nothing can be substituted for water.
Global climate change and increased human consumption have aggravated the uneven spatiotemporal distribution of watershed water resources, affecting the water provision supply and demand state. However, this problem h...Global climate change and increased human consumption have aggravated the uneven spatiotemporal distribution of watershed water resources, affecting the water provision supply and demand state. However, this problem has often been ignored. The present study used the Xiangjiang River basin(XRB) as the study area, and the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST) model, demand quantification model,supply–demand ratio, and water flow formula were applied to explore the spatial heterogeneity, flow, and equilibrium between water supply and demand. The results demonstrated significant spatial heterogeneity in the upstream, midstream, and downstream regions.The areas of water shortage were mainly located the downstream of the Changsha–Zhuzhou–Xiangtan urban agglomeration, and the Hengyang basin was the most scarcity area. Affected by terrain gradients and human needs, water flow varied from-16.33 × 10^(8) m^(3) to 13.69 × 10^(8) m^(3)from the upstream to the downstream area, which provided a possibility to reduce spatial heterogeneity. In the future, measures such as strengthening water resource system control,sponge city construction, and dynamic monitoring technology should be taken to balance the supply and demand of water in different river sections of the basin. This study can provide references for regulating water resources allocation in different reaches of the basin.展开更多
A water-conducting polyacrylamide/montmorillonite coating was prepared by solutionblending.The coating was coated on fiber and then composited with polymer to form a composite film material that used for water saving ...A water-conducting polyacrylamide/montmorillonite coating was prepared by solutionblending.The coating was coated on fiber and then composited with polymer to form a composite film material that used for water saving and tree planting in arid and desert regions.The coating's water-conducting characteristics and dynamic self-adjusting behavior were investigated by Fourier transform infrared(FTIR)spectroscopy,thermal analysis(TG-DTA),and environmental scanning electron microscopy(ESEM).The results showed that the coating's water-conducting rate increased but water-retention capacity weakened with increasing montmorillonite content.The water-loss rate was positively related to temperature and negatively related to soil moisture.Water potential greatly influenced the water-conducting rate of the coating during its water conduction process.When the coating was at a low water potential,the montmorillonite particles interconnected and water was conducted quickly via montmorillonite layers,whereas when the coating was at a high potential,the montmorillonite particles disconnected and water was conducted slowly via the swelled polyacrylamide net structure.The rate can be regulated by changing the proportion of polyacrylamide and montmorillonite to guarantee a reasonable water supply for trees and make trees easier to survive.Thus,the survival rate of trees can be increased and the use of water resources can be significantly reduced.展开更多
This study aimed to explore the potential of developing a novel cooling system combining a greenhouse and an earth-tube heat exchanger(ETHE).In this system,greenhouse air is circulated through the underneath soil mass...This study aimed to explore the potential of developing a novel cooling system combining a greenhouse and an earth-tube heat exchanger(ETHE).In this system,greenhouse air is circulated through the underneath soil mass to use the deep-soil cooling effect.This was achieved through the following steps.First,soil temperature profile inside and outside the cultivated greenhouse was monitored for almost one year to study the possibility of using deep-soil coldness for cooling the greenhouse air.Second,a prototype ETHE was built to practically investigate the potential reduction in air temperature as the air flows inside the deep earth pipes.Third,a prototype greenhouse was erected to study the ETHE concept.Results from the first experiment revealed that soil temperature at a soil depth of 2.5 m inside the greenhouse offers good conditions to bury the ETHE.The soil temperature at this soil depth was below the maximum temperature(32℃)that most greenhouse crops can withstand.Results from the prototype ETHE showed a slight reduction in air temperature as it passed through the pipes.From the prototype of the integrated greenhouse and ETHE system,reduction in air temperature was observed as the air passed through the ETHE pipes.At night,the air was heated up across the ETHE pipes,indicating that the ETHE was working as a heater.We concluded from this study that greenhouses in arid climates can be cooled using the ETHE concept which would save a large amount of water that would otherwise be consumed in the evaporative coolers.Further investigations are highly encouraged.展开更多
This study aimed to compare the effects of two types of drip irrigation line design on cotton yield, water use, and net returns. The experiments were carried out in the arid region of Xinjiang, Northwest China, during...This study aimed to compare the effects of two types of drip irrigation line design on cotton yield, water use, and net returns. The experiments were carried out in the arid region of Xinjiang, Northwest China, during 2009-2010 growing years. The two types of lateral placement are commonly used by the local farmers in the area: double lines (two laterals controlling four rows) and single line designs (one lateral controlling four rows). The results indicated that less irrigation water was applied by single line compared with double lines design. This implies that more irrigation water could be saved using single line, by reducing the water consumption of cotton. The emergence rates for double lines were 2 and 6% higher than those for single line design in 2009 and 2010. The seed cotton yields for double lines design were 5.76 and 6.41 Mg ha-1 which were 13 and 9% higher than for single line design in 2009 and 2010, respectively. Single lines could however lower the investment cost compared to double lines, which produced 10 and 7% more net income in 2009 and 2010, respectively. By contrast, the double lines was more profitable and suitable for the farmers in Northwest China than single line design.展开更多
文摘A model of fuzzy comprehensive evaluation for water saving irrigation system (WSIS) decision making is proposed based on establishing an index system affected by six kinds of basic factors including qualitative and quantitative indexes. The object function of WSIS is set up by using the concept of fuzzy membership degree, it is to transform characteristic vector matrix into unify membership matrix and extending the least square method to the least of weighted distance square. The optimum weighted membership degree and the inferior weighted membership degree are used to solve the object function. This method effective solves the problem of classify for fuzzy attributive indexes and the problem of optimum for the set of different attributive indexes. A case study shows that the fuzzy comprehensive evaluation model is reasonable and effective in decision making for water saving irrigation system planning.
基金Tarim Oilfield Corporation of China National Petroleum Corporation for providing funds
文摘Evaporation loss from the saturated soil beneath drip irrigation emitters highly influences the irrigation efficiency of drip krigation (D1]. Subsurface drip irrigation (SDI) is one good approach to curb this inefficiency, but in a new irrigation method, straight tube irrigation (STI), the irrigation tubes do not need to be buried and thus STI is recommended to increase the irrigation efficiency under normal surface-applied DI. STI consists of only connectors and water-transference tubes that can directly transfer irrigation water from the lateral emitters in the drip line to the root zone of plants. Five-month field experiments were carried out in aeolian sand soil in the forest-belts of the Taklimakan Desert, which have poor water storage capacity, to compare the potential water saving between STI and DI. The preliminary results showed that, compared with DI, STI (1) improved the soil water content in soil depths from 40 to 100 cm under the soil surface; (2) achieved the same irrigation effects in relatively shorter irrigation durations; (3) had very little water loss due to deep seepage; and (4) formed a layer of dry sand about 10 to 30 cm thick immediately below the soil surface, which lessened evaporation loss of soil water beneath the emitters on the soil surface. This demonstrates that STI can maximize the water-saving potential of DI through the reduction of wetted soil perimeters on the soil surface. This is valuable information for water-saving engineering applications and projects with STI in arid and semiarid regions.
基金Project supported by the National High-Tech Research and Development program of China (863 Program ) (No.2 0 0 2 AA2 Z42 5 1-2 10 0 41) Postdoctoral Scientific Foundation of Northeast Agricultural U niversity. (No. 2 40 0 0 9) and postdoctoral Scien
文摘Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is based on the matter-element analysis and combined with the concepts of fuzzy mathematics,which is called the method of fuzzy matter-element analysis.It constructs the compound fuzzy matter element with the investment projects,evaluation factors and their fuzzy value.Through establishing the best subjection degree (fuzzy value),complex fuzzy matter element of relational coefficient and weight aggregation of fuzzy matter-element model,the writer achieves on optimum order of the investment projects according to the calculated relational degree and finds the best project.In this paper,the calculation of weight adopts the analytical hierarchy process method(AHP).Through the actual example,it shows that the model is simple and its calculation is reliable.It is very significant for the engineering evaluated bid and investment decision.
基金supported by the National Natural Science Foundation of China(41025001and41130640)the Fundamental Research Funds for Central Universities of China,and Program for Changjiang Scholars and Innovative Research Team in University,China(IRT1108)
文摘Water is the source of all the creatures on the earth and energy is the main factor driving the world. With the increasing population and global change, water and energy conservation have become worldwide focal issues, particularly in the water-stressed and energy-limited regions. Rainwater harvesting, based on the collection and storage of rainfall runoff, has been widely used for domestic use and agricultural production in arid and semiarid regions. It has advantages of simple operation, high adaption, low cost and less energy consumption. This study reviewed rainwater harvesting systems adopted in the Loess Plateau of China and analyzed water use efficiency (WUE) for various rainwater harvesting techniques. Supplemental irrigation using harvested rainwater could increase crop yield by more than 30%, and WUE ranged from 0.7 to 5.7 kg m4 for spring wheat, corn and flax, and 30-40 kg m-3 for vegetables. Moreover, energy consumption for rainwater harvesting based on single family was compared with traditional water supply in the city of the Loess Plateau using the life cycle assessment (LCA) method. Results showed that energy consumption yielded per unit harvested rainwater was 25.96 MJ m-3 yr which was much less than 62.25 MJ m3 yr^-1 for main water supply in Baoji City, Shanxi Province, meaning that rainwater harvesting saved energy by 139.8% as compared to the main water supply system. This study highlights the importance and potential of rainwater harvesting for water and energy conservation in the near future.
基金National"863"High-Technique Programm e.(No.2 0 0 2 AA2 Z42 5 1-2 10 0 41) Postdoctoral Scientific Foundation of NEAU(No.2 3 0 0 0 9) and Postdoctoral Scientific Foundation of Heilongjiang Province.
文摘Through applying PPE model based on RAGA to evaluate the benefit of rice water saving,the author turns multi-dimension data into low dimension space.So the optimum projection direction can stand for the best influence on the collectivity.Thus,the value of projection function can evaluate each item good or not.The PPE model can avoid jamming of weight matrix in the method of fuzzy synthesize judgement,and obtain better result.The author wants to provide a new method and thought for readers who are engaged in investment decision-making of water saving irrigation and other relative study.
文摘Drip irrigation system can achieve high uniformity. When the system is designed for uniformity coefficient equal or more than 70%, the water application in the field can be expressed as a normal distribution and further simplified to a linear distribution. This paper will describe the irrigation scheduling parameters, percent of deficit, application efficiency and coefficient of variation by simple mathematical model. Using this effective model and the irrigation application, the total yield affected by the total water application for different uniformity of irrigation application can be determined. More over, this paper uses the cost of water, price of yield, uniformity of the drip irrigation system, crop response to water application and environmental concerns of pollution and contamination to determine the optimal irrigation schedule. A case study shows that the optimal irrigation schedule can achieve the effect of water saving and production increment compared with the conventional irrigation schedule in which the whole field is fully irrigated. Key words drip irrigation - linear cumulative frequency curve - optimal irrigation schedule - water saving - production increment CLC number TV 139.1 Foundation item: Supported by the National Natural Science Foundation of China (59379407)Biography: QIU Yuan-feng (1973-), male, Ph. D, research direction: water saving irrigation theory and techniques.
文摘Irrigation water supply is one of the vital components for sustainable rice farming, which is becoming a limiting resource in the changing climatic condition. An experiment was conducted at the research field of Bangladesh Agricultural University, Mymensingh during dry season from January-June of 2017 to investigate the suitability of Alternate Wet and Dry Irrigation (AWDI) for sustainable rice production and reducing methane emission. The modern rice variety BINA Dhan 10 was used as test crop. There were five irrigation treatments viz. T<sub>1</sub> (saturated condition), T<sub>2</sub> (continuous flooded, 5 cm standing water), T<sub>3</sub> (AWDI-10 cm;irrigated when water level fell 10 cm from surface), T<sub>4</sub> (AWDI-15 cm;irrigated when water level fell 15 cm from surface) and T<sub>5</sub> (AWDI-20 cm;irrigated when water level fell 20 cm from surface). Results of the field trial showed satisfactory grain yield and low seasonal methane emission along with significantly high irrigation water savings (%) in AWDI treated field plots. Among the treatments, T<sub>3</sub> (AWDI-10 cm) and T<sub>4</sub> (AWDI-15 cm) showed higher yield performance (6250kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#f7f7f7;"=""><sup>.</sup></span>ha<span style="color:#FFFFFF;font-family:" white-space:normal;background-color:#d46399;"=""><span style="color: rgb(79, 79, 79);" font-size:14px;white-space:normal;background-color:#ffffff;"=""><sup>-</sup></span></span><sup>1</sup> and 5810 kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#f7f7f7;"=""><sup>.</sup></span>ha<sup><span style="white-space:nowrap;">-</span>1</sup>, respectively) with lower CH<sub>4</sub> emission (reduced up to 36% and 40%, respectively) compared to continuous flooded treatment (T2, CF 5 cm water). In AWDI field plots less irrigation frequency (6 - 9) was required which significantly saved the amount of irrigation water (12% - 24%). Although T<sub>5</sub> (AWDI-20 cm) showed the highest water savings (24%) and lowest CH<sub>4</sub> emission (reduced up to 50%);however the lowest grain yield (4283 kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#f7f7f7;"=""><sup>.</sup></span>ha<span style="color: rgb(79, 79, 79);" font-size:14px;white-space:normal;background-color:#ffffff;"=""><sup>-</sup></span><sup>1</sup>) was found under this treatment. On the other hand, continuously irrigated (T2, 5 cm standing water) field plot showed lower yield (4783 kg<span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#f7f7f7;"=""><sup>.</sup></span>ha<sup><span style="color:#4F4F4F;font-family:-apple-system, " font-size:14px;white-space:normal;background-color:#ffffff;"="">-</span>1</sup>) but significantly higher methane emissions compared to other treatments during rice cultivation. Water productivity index was also found higher in AWDI treated field plots compared to continuously irrigated field plot. At the reproductive stage of rice plant well-developed aerenchyma tissue was observed in root cortex under the continuous irrigated field plot, which indicates higher diffusion pathway of methane gas from root rhizosphere to the atmosphere compared to other treatments. Therefore, alternate wet and dry irrigation water management practice may be recommended at farmers’ level for sustainable rice production and reducing methane emission during dry winter Boro season which will reduce the cost of production by water saving as well as energy saving.
文摘With the development of the production scale and the increasing of the process technologies and facilities,product quality and the requirement of water supply continuously put forward new requirements to water treatment technology.The practice of the water saving technology should ensure the safe of water using and the innovation of technique data.Especially the stabilization of water quality should also meet the production at full capacity,reduce equipment failure rate and maintain the sustainable development under the condition of the minimal resource consumption.This article describes the practice of Baosteel saving technology,water-saving ideas from the system to start,according to Baosteel raw water intake requirements and process water and drainage characteristics,water and salt water tidal according to changes in the Yangtze River and the Yangtze River upstream and downstream trends in water discharge on water quality factors,established the electrical conductivity,chloride ion indicators for the control of the Yangtze River water,the implementation of 'avoid salt build light' water at the same time,combined with the actual situation of water pollution in the Yangtze River,the use of force coefficient correlation theory,the implementation of 'avoid taking clear pollution' to ensure the quality of raw water intake. System and cascade utilization of water,process water,based on whole plant water balance testing, analysis,technical parameters of the system and processes the user running the pressure balance pipe network,and implemented a stabilization system to adjust water pressure,reducing the water supply network systemwater loss;application of electrochemical principles,the implementation of the protection of underground pipes Baosteel,implemented a water use,steps to use,the operating mode of water supply in series to increase water reuse,reduce wastewater discharge system. Water quality stability and water-saving in the process;carry out water quality stability technology in the different complicated processes of the steel industry;apply the environmental protection and water quality, sterilization,non-phosphorus and low phosphorus technologies which are suitable for high concentration of circulating water.By these technologies,we achieved the water-saving in the process in different seasons and solved the technical problems affecting production such as equipment corrosion,scaling and the formation of the water quality proprietary technology under the conditions of high heat load production as well. The use of water ecological conservation and biological treatment technology:the implementation of the reservoir to the ecological technology is characterized by food chain and wetland environmental technology characterized by plants chain.Reservoir ecological management techniques in the use of natural conditions, wind direction,temperature,light and fish biomass in the reservoir water level regulation of balance and combination of organic,control and resolve the reservoirs in spring and summer algae problems and water quality changes rot of the 'fresh' operating problems.The artificial wetland technology develops a new way for metallurgical plants' wastewater treatment.All the measures by the implementation of water to create the conditions for the system to achieve the water target of constant innovation,reaching the advanced level of iron and steel enterprises.
文摘The development of water-saving agriculture is of great significance not only for increasing farmers’ production and income, but also for protecting water resources. The purpose of this paper is to learn from the experience of Israel, Japan, Korea and Singapore, improve the low efficiency of agricultural water use in China, and solve the problem of water shortage, promote the development of agriculture. This article concludes that the experience of water-saving agriculture in Israel is advanced irrigation technology, sound laws and regulations, and emphasis on science and technology. Japan’s water-saving agriculture is characterized by an efficient irrigation program and a strict agricultural water management policy. Korea’s experience in water-saving agriculture is that it has a strict water management system, with the government subsidizing the cost of irrigation projects and integrating water into agricultural development planning. Singapore’s experience in water-saving agriculture is to raise awareness of water conservation and to use step water prices. In order to promote the sustainable development of water-saving agriculture in China, the research on water-saving agriculture in the future can be carried out from the aspects of agricultural production or related agricultural technology.
文摘This paper is concerned with water saving for water-loop cooling tower system in power plants. A newly developed water saving device of swirling flow is presented. The key point is that the new water saving device makes the steam swirl up along the device wall rather than engender laminar flow in a corrugated plate. The corrugated plate device can save approximately 10 percent of the total lost water. In contrast to the scale model of corrugated plate water saving device, experimental analyses have demonstrated that the new water saving device of swirling flow is more efficient, with a capacity of saving more than 20 percent of water.
文摘Jointly hosted by the Standardization Administration of China (SAC) and the National Development and Reform Commission, the Meeting for Promotion of the Standards for Water Saving was held in Beijing on Oct. 5th, 2004, with the aim of promoting development of water intake technology, improving efficiency of water using and developing recycle economy. The meeting analyzed the current
文摘Agricultural irrigation is a primary user for freshwater withdrawal. Irrigation plays an important role in crop production, as it provides the benefit of reducing the effects of prolonged dryness and erratic precipitation. Center pivot irrigation system is the most common irrigation system in agriculture. As the center pivot irrigation system ages, the system could develop a leaking joint, clogged sprinklers, and physical damage. This can cause areas of non-uniformity that can lead to under- or over-irrigated in some areas of the land, resulting in excess energy use and cost, wasting resources, and environmental impacts. Thus, it is important to evaluate the performance of a center pivot irrigation system regularly to maximize return on investments and minimize wasting resources. This study focuses on evaluating the impacts and benefits of improved center pivot irrigation distribution uniformity by performing distribution uniformity evaluations pre- and post-retrofit. This study also focused on demonstrating an unmanned aerial vehicle (UAV) to assess the performance of the center pivot irrigation system in two irrigated farmlands. The Coefficient of Uniformity (CU), Distribution Uniformity (DU), and Scheduling Coefficient (SC) were calculated based on the catch can test data. The values were utilized to evaluate water and energy savings from the improved coefficients. The team has found that replacing sprinkler packages increased the CU from 78 to 89 and the DU from 77 to 82, and reduced the SC from 1.3 to 1.2 in Field A. In Field B, replacing sprinkler packages increased the CU from 73 to 91 and the DU from 62 to 84 and reduced the SC from 1.6 to 1.2. The estimated water savings in Field A due to the reduced scheduling coefficient was approximately 151,000 liters/hectare/year, with consideration of the corn and soybean rotation field in Michigan. The estimated water savings in Field B was 608,000 liters/hectare/year. The data from this demonstration study showed the value of distribution uniformity evaluation and retrofit of irrigation systems. This information will encourage farmers and agricultural industries to consider performing more distribution uniformity evaluations, ultimately improving irrigation water use efficiency and supporting sustainable water management in agriculture.
文摘In an effort to save the precious water resource and reduce the environmental impact, Fong’s Industries Group along with its member companies, namely "Fong’s National", "THEN", "Goller" and "Fong’s Water Technology" provide an ecological dyeing solution to reduce the water consumption drastically through their innovative technologies covering the processes from yarn dyeing to piece dyeing and recycling of discharge after dyeing and finishing.
文摘AMONG the chain of lakes on the bottom of the western Great Rift Valley, Lake Tanganyika stands out for its extraordinary north-south extension and depth. With its large size and high biodiversity, Lake Tanganyika is of great social, economic, political and environmental significance to neighboring countries. However, the water quality of the lake is on the decline due to the mounting environmental chal- lenges it faces. Chinese scientists under the UNEP-China-Africa Cooperation Program on Environment are working closely with African partners to find out the sources of the pollution and possible solutions with a focus on water quality monitoring and treatment.
文摘The most restrictive factor in the way of economic prosperity in China’s northwest lies in the lack of water resources.To seek countermeasures against this ages-old scourge of the arid hinterland,the CAS Division of Earth Sciences sponsored a workshop in Beijing on tapping water resources of Chinese northwest in March 1995 and decided to organize an expedition team of CAS members to investigate the water resources there.From August 23 to September 5,1995,the team carried out an on-the-spot survey along a 3,000-kilometre-long itiner-
文摘Water is the source of life,the soul of cities,the keyof agriculture,and the blood of industry.Nobody can livewithout water,and nothing can be substituted for water.
基金supported by National Natural Science Foundation of China(grant number 42171258,41877084)Natural Science Foundation of Hunan Province(grant number 2021JJ30448)。
文摘Global climate change and increased human consumption have aggravated the uneven spatiotemporal distribution of watershed water resources, affecting the water provision supply and demand state. However, this problem has often been ignored. The present study used the Xiangjiang River basin(XRB) as the study area, and the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST) model, demand quantification model,supply–demand ratio, and water flow formula were applied to explore the spatial heterogeneity, flow, and equilibrium between water supply and demand. The results demonstrated significant spatial heterogeneity in the upstream, midstream, and downstream regions.The areas of water shortage were mainly located the downstream of the Changsha–Zhuzhou–Xiangtan urban agglomeration, and the Hengyang basin was the most scarcity area. Affected by terrain gradients and human needs, water flow varied from-16.33 × 10^(8) m^(3) to 13.69 × 10^(8) m^(3)from the upstream to the downstream area, which provided a possibility to reduce spatial heterogeneity. In the future, measures such as strengthening water resource system control,sponge city construction, and dynamic monitoring technology should be taken to balance the supply and demand of water in different river sections of the basin. This study can provide references for regulating water resources allocation in different reaches of the basin.
基金Funded by the National Science Foundation of China(No.50772131)the National High-tech R&D Program of China(863Program)(No.2011AA322100)+1 种基金the Key Project of Chinese Ministry of Education(No.106086)the Fundmental Research Funds for the Central Universities(No.2010YJ05)
文摘A water-conducting polyacrylamide/montmorillonite coating was prepared by solutionblending.The coating was coated on fiber and then composited with polymer to form a composite film material that used for water saving and tree planting in arid and desert regions.The coating's water-conducting characteristics and dynamic self-adjusting behavior were investigated by Fourier transform infrared(FTIR)spectroscopy,thermal analysis(TG-DTA),and environmental scanning electron microscopy(ESEM).The results showed that the coating's water-conducting rate increased but water-retention capacity weakened with increasing montmorillonite content.The water-loss rate was positively related to temperature and negatively related to soil moisture.Water potential greatly influenced the water-conducting rate of the coating during its water conduction process.When the coating was at a low water potential,the montmorillonite particles interconnected and water was conducted quickly via montmorillonite layers,whereas when the coating was at a high potential,the montmorillonite particles disconnected and water was conducted slowly via the swelled polyacrylamide net structure.The rate can be regulated by changing the proportion of polyacrylamide and montmorillonite to guarantee a reasonable water supply for trees and make trees easier to survive.Thus,the survival rate of trees can be increased and the use of water resources can be significantly reduced.
基金the Sultan Qaboos University and United Arab Emirates University for the research fund(CL/SQU-UAEU/15/04).
文摘This study aimed to explore the potential of developing a novel cooling system combining a greenhouse and an earth-tube heat exchanger(ETHE).In this system,greenhouse air is circulated through the underneath soil mass to use the deep-soil cooling effect.This was achieved through the following steps.First,soil temperature profile inside and outside the cultivated greenhouse was monitored for almost one year to study the possibility of using deep-soil coldness for cooling the greenhouse air.Second,a prototype ETHE was built to practically investigate the potential reduction in air temperature as the air flows inside the deep earth pipes.Third,a prototype greenhouse was erected to study the ETHE concept.Results from the first experiment revealed that soil temperature at a soil depth of 2.5 m inside the greenhouse offers good conditions to bury the ETHE.The soil temperature at this soil depth was below the maximum temperature(32℃)that most greenhouse crops can withstand.Results from the prototype ETHE showed a slight reduction in air temperature as it passed through the pipes.From the prototype of the integrated greenhouse and ETHE system,reduction in air temperature was observed as the air passed through the ETHE pipes.At night,the air was heated up across the ETHE pipes,indicating that the ETHE was working as a heater.We concluded from this study that greenhouses in arid climates can be cooled using the ETHE concept which would save a large amount of water that would otherwise be consumed in the evaporative coolers.Further investigations are highly encouraged.
基金supported by the National High-Tech R&D Program of China (2011AA100507)the Action Plan for the Development of Western China of the Chinese Academyof Sciences (KZCX2-XB3-16)the National Science Foundation for Young Scientists of China (51009126)
文摘This study aimed to compare the effects of two types of drip irrigation line design on cotton yield, water use, and net returns. The experiments were carried out in the arid region of Xinjiang, Northwest China, during 2009-2010 growing years. The two types of lateral placement are commonly used by the local farmers in the area: double lines (two laterals controlling four rows) and single line designs (one lateral controlling four rows). The results indicated that less irrigation water was applied by single line compared with double lines design. This implies that more irrigation water could be saved using single line, by reducing the water consumption of cotton. The emergence rates for double lines were 2 and 6% higher than those for single line design in 2009 and 2010. The seed cotton yields for double lines design were 5.76 and 6.41 Mg ha-1 which were 13 and 9% higher than for single line design in 2009 and 2010, respectively. Single lines could however lower the investment cost compared to double lines, which produced 10 and 7% more net income in 2009 and 2010, respectively. By contrast, the double lines was more profitable and suitable for the farmers in Northwest China than single line design.