Eco-environmental Water Requirements Research Articles

Calculation of targeted eco-environmental water requirements in a dry inland river: a case study of the Yarkand River Basin, Xinjiang, China

Analysis of eco-environmental water requirements along a dry inland river under extreme drought conditions can provide a theoretical basis for the sustained utilization and management of water resources in arid regions. This paper uses the Yarkand River Basin in Xinjiang, China, as a case study to determine and assess a method to calculate targeted eco-environmental water requirements (TEEWR) for different ranges of ecological protection of inland riparian forests. The proposed method is intended to comprehensively analyze the water resources along arid inland rivers. Specifically, the ranges of ecological protection were gradually expanded at intervals of 1 km (or multiples of the smallest distance) away from the river course while the TEEWR was determined as a function of the ecological water demand of riparian forest vegetation (Yec) and its corresponding river loss (Xloss). The developed method was shown to be feasible for analyzing TEEWR in the Yarkand River Basin and thus provides a novel and effective approach for the rational utilization and management of water resources in inland river basins in arid regions.Article HighlightsZones of ecological protection were gradually expanded at intervals of 1 km (or multiples of the smallest distance) away from the river course on both sides of the dry inland riverThe targeted eco-environmental water requirement, defined as the ecological water demand of riparian forest vegetation (Yec) and its corresponding river loss (Xloss), was determined for a dry inland river basinThe developed methods for calculating targeted eco-environmental water requirements are useful, but have limitations.

Suitable eco-environmental water requirement in Sanmenxia Reservoir wetland based on 3S technology

Suitable eco-environmental water requirement in Sanmenxia Reservoir wetland based on 3S technology

Quantitative Determination of Some Parameters in the Tennant Method and Its Application to Sustainability: A Case Study of the Yarkand River, Xinjiang, China

Analysis of basic eco-environmental water requirements (BEEWRs) along inland rivers characterized by extreme aridity can provide a theoretical basis for sustaining riverine ecosystems stressed by increasingly dry conditions and human activity. In the past, analyzing the ecological base flow as determined by the Tennant method was the predominant method used to calculate the BEEWR of a river. However, some parameter values within this method are determined subjectively, increasing uncertainty in the estimated values. In this paper, quantitative methods for these subjectively determined parameters are proposed and used to analyze the BEEWR of the Yarkand River, Xinjiang, China. The results demonstrate that: (1) the flood and non-flood seasons of a river can be delineated by analyzing the increase rate of monthly runoff as compared to the monthly runoff of the previous month; (2) the ecological base flow standard in the Tennant method can be more quantitatively determined by comparing the BEEWR for each ecological base flow standard to the annual average river loss, where the BEEWR must exceed the annual average river loss; and (3) BEEWRs of other up- and downstream river reaches can be obtained using the formula “BEEWR in the next downstream section equals the BEEWR in the last section minus the river loss between these two sections”.

Basic and target eco-environment water requirements of a dry inland river under typical flow frequencies in China.

Analysis of eco-environmental water requirements (EEWRs) and water resource allocation strategies for arid, inland river basins can provide the theoretical basis for sustainable water utilization and management. In this paper, an optimal water resource allocation strategy is proposed for Yarkand River Basin in Xinjiang, China, on the basis of a comprehensive analysis of runoff data collected between 1970 and 2016, three ecological environmental protection goals, basic eco-environmental water requirement (BEEWR) aimed at sustaining aquatic ecosystems within the river, and target eco-environmental water requirements (TEEWR) aimed at protecting various types of riparian vegetation along the river. The results showed that: (1) after the runoff in Kaqun reach subtracting the BEEWR, the annual average river loss (recharge), and the amount of water diversion for irrigation (51.43 × 108 m3) from flows along the Kaqun reach, the remaining water volume during wet years was able to meet all three TEEWRs; (2) during moderately wet years, the remaining water was capable of meeting the second and third TEEWRs; and (3) during dry and extremely dry years, there was little or no residual water available to meet TEEWRs. The proposed optimal water resource allocation strategy, based on the above findings, states that the water diversion requirement for irrigation and domestic use allocated from the total amount of runoff should not exceed the National Water Policy (Three Red Lines) standard first. Then, the BEEWR allocated from the runoff should be met second, and the annual average river loss, third. Depending on the amount of remaining water, the second and third TEEWRs can be fulfilled during wet years, but during moderately wet years, only the third TEEWR can be met. During dry and extremely dry years, only the BEEWR of the river can be met and only during the flood season.

Eco-environmental water requirements in Shuangtaizi Estuary Wetland based on multi-source remote sensing data

Abstract With rapid economic development and expansion of urban boundaries, increasingly damaged wetland resources have seriously threatened the ecosystem. The study of eco-environmental requirements of wetlands is not only the basis of water resources allocation in development and utilization, but also for creating a sustainable system to maintain and improve the overall ecosystem. In this study, we used the Shuangtaizi Estuary Wetland as our study area. The breakdown of wetland cover types was extracted based on multi-source remote sensing data, providing the graphic database for ecological water requirement calculation. According to the characteristics of the Shuangtaizi Estuary Wetland ecosystem, the methods of quantifying the components of ecological water requirements were determined. The results showed that the optimum ecological water requirement of the total wetland was 239 million m3. The minimum, 75th percentile frequency, and 95th percentile frequency water requirements were 670 million m3, 921 million m3, and 1,078 million m3, respectively.

Using a three-tier model to optimize the allocation of river water resources to meet eco-environmental water requirement targets

Abstract It is difficult to simultaneously manage the dynamic demands for river water quality and quantity, and reconcile the contradiction between socio-economic and eco-environmental water consumption. As a solution, we proposed a three-tier model to optimize the distribution of river water resources. Using three constraint conditions, namely the ratio of wastewater to clean water, the eco-environmental water requirements of each node and the use of wetland projects, we determined various water quantity and quality allocation scenarios. We tested the model on the Qingyi River, and found that, for the recommended scenario that involved enhanced water-saving, a wastewater/clean water ratio and wetlands, more than 80% of the eco-environmental water requirements of each node except for the Luma section were achieved for each month. While the water quality in some individual river sections did not meet the standards for a few months of the year, the water quality of the remaining sections could be improved from class V, the current state, to class IV, and ammonia nitrogen and chemical oxygen demand (COD) standards could be achieved 82% and 96% of the time, respectively. These results show that the proposed model is effective and fit for purpose.

基于生态保护目标的疏勒河中游绿洲生态环境需水研究

基于生态保护目标的疏勒河中游绿洲生态环境需水研究

A Method for Temporary Water Scarcity Analysis in Humid Region Under Droughts Condition

Water scarcity in China has long been discussed and studied, mostly in arid and semi-arid Northern China. However, temporary water scarcity caused by seasonal droughts hasn’t drawn enough attention still, while some humid regions in South China are readily to be encountered with seasonal droughts, especially in the background of climate change. In this study, a method based on System Dynamics (SD) and mathematical optimization is developed to analyze the situation of temporary water scarcity and optimize the water allocation under seasonal droughts, considering rapid urbanization, industrialization, and increasing food demand. And a case study in Nanchang Municipality, a typical humid region in Southern China, is presented. The simulation results show that conventional management scenarios including enforcing demand reduction strategies and increasing local water supply will not fill the water shortage gap, and the total water shortage rate will retain more than 9.0 % in special drought condition. Thus, we examine the water transfer scenario, and it proves to be effective in coping with the water shortage gap. The optimization results indicate that the water transferred from Ganjiang River to Fuhe River Water Demand Subsystem may account for 50.21 % of the total fresh water supply of Fuhe River Water Demand Subsystem, in September, under a certain drought condition. In addition, the current situation reveals fierce competition between social economic water needs and eco-environmental water requirements in local scale in dry condition. The situation argues that management of the distribution of water in space must be involved, and the simulation of the inter-basin transfer scenario proves it a necessary and effective countermeasure.

Calculation of Eco-Environmental Water Demand for River Dalinghe

According to the characteristics of north river, this paper used the minimum monthly average runoff method, the environmental function setter method and the annual average sediment concentration method to calculate the eco-environmental water requirement of mainstream of River Dalinghe. The results showed that: the non-consumptive water requirement was 4.46×108m3 for Shangwobao Station, 8.87×108m3 for Chaoyang Station, 13.96×108m3 for Yixian Station and 7.26×108m3 for Linghai Station per year; the evaporative water requirement was 0.019×108m3, and the leakage water requirement was not taken into account in the consumptive water requirement. The eco-environmental water requirement of mainstream of River Dalinghe can not be satisfied basically, the management department should control the disposal of sewage strictly for it.

Water Demand Forecast in the Baiyangdian Basin with the Extensive and Low-Carbon Economic Modes

The extensive and low-carbon economic modes were constructed on the basis of population, urbanization level, economic growth rate, industrial structure, industrial scale, and ecoenvironmental water requirement. The objective of this paper is to quantitatively analyze effects of these two economic modes on regional water demand. Productive and domestic water demands were both derived by their scale and quota. Ecological water calculation involves the water within stream, wetland, and cities and towns. Total water demand of the research region was obtained based on the above three aspects. The research method was applied in the Baiyangdian basin. Results showed that total water demand with the extensive economic mode would increase by 1.27 billion m3, 1.53 billion m3, and 2.16 billion m3in 2015, 2020, and 2030, respectively, compared with that with low-carbon mode.

The research of ecology-oriented reasonable deployment of water resources at Shuangtaizi estuary wetland

Shuangtaizi estuary wetland, the largest natural conservation district in China, and one of the best preserved, largest ecological lands with the most complete vegetation types in the world, is located in Panjin city, Liaoning Province. In recent years, the degradation of Shuangtaizi estuary wetland is very serious. In order to rescue lives in the wetland and protect valuable natural resources, the information system of Shuangtaizi estuary wetland was built with '3S' technology, and the minimum, optimum, and maximum eco-environmental water requirements were calculated respectively. Furthermore, for restoring the ecological functions of wetland and preventing wetland degradation, the balance between supply and demand of water resource was analyzed , and an optimal allocation scheme of water resources was proposed based on three kinds of equilibrium.

The Research Progress of Ecological Water Requirement in China and Abroad

Based on the research results of the ecological water requirement both in China and abroad, this study divided the research process of the ecological water requirement into four stages .The embryonic stage of ecological water requirement from 1940s to 1970s, represents the rapid development of the in-stream flow methods and the preliminary discusses of the determination of the minimum stream flow. During this stage the formal view of the ecological water requirement was not formed. The view of the ecological water requirement was formed during 1980s, mainly represented the maturation of the study in stream discharge in foreign countries, the formation of the allocation study's embryonic of eco-environmental water requirement and the initial proposal of ecological water requirement problems .The broad scale research of ecological water requirement which have been a focus around the world from 1990s to the early 21st century, mainly represented the essential perfection of the conception of the ecological water requirement and the development of the related theory and methods. Since the21st century, the inclined maturity stage mainly represents the further study of the conception and the methods of all kinds of ecological water requirement.

Incorporating Eco-environmental Water Requirements in Integrated Evaluation of Water Quality and Quantity—A Study for the Yellow River

River water has dual functions; it can be withdrawn for agricultural, industrial, and domestic uses and provides eco-environmental water (EEW) for riverine systems. A concept of intensity of ecological function of river water (IEFRW) has been put forward, and an integrated water quantity and quality evaluation method in combination with eco-environmental water requirements has been developed for a river. Based on the monthly data of water quality and quantity as well as the withdrawals during 1997 to 1999, an integrated evaluation of water resources has been conducted for the Yellow River. The results indicated that actual IEFRW can directly reflect the health state of riverine ecosystems. The actual increments of water resources availabilities caused by providing EEW for the riverine systems were lower than the eco-environmental water requirements of the riverine ecosystem, leading to the intermittent interruption of river flow and other eco-environmental problems of the Yellow River.

Eco-environmental water demands for the Baiyangdian Wetland

In recent years, the hydrological characters of Baiyangdian Wetland have changed greatly, which, in turn, influence the biotic component, the structure and function of the wetland ecosystem. In order to determine the demands for water resources of ecological wetland system, a method of ecological water level coefficient was suggested to calculate the water resources demands for wetland environment use. This research showed that the minimum coefficient is 0.94 and the optimal coefficient is more than 1.10. According to these two coefficients, the ecological water level and water quantity can be estimated. The results indicate that the amount of the minimal and optimal eco-environmental water requirements are 0.87 × 108 and 2.78 × 108 m3 in average monthly, respectively, with the maximum eco-environmental water requirement in summer and the minimum in winter. The annual change of eco-environment water demand is in according with the climate change and hydrological characters. The method of ecological water level emphasizes that wetland ecosystem adapts to the hydrological conditions, so it can be used in practice well.

Eco-environmental water requirement in the Zhalong Wetland

The method for calculating the eco-environmental water requirement in the Zhalong Wetland are studied, and the methods for calculating the appropriate quantity of the eco-environmental water requirement and calculating the minimum quantity of the eco-environmental water requirement are put forward. The eco-environmental water requirement in all kinds of the land use area in the Zhalong wetland including the lake, in the swampland saturating with water and in the swampland covering with bulrush, the appropriate quantity of the eco-environmental water requirement and the minimum quantity of the eco-environmental water requirement are calculated and analyzed. It is concluded that, the quantity of the eco-environmental water requirement in the whole Zhalong Wetland varies from 522 millions m3 to 592 millions m3 during from 1986 to 2002, the appropriate quantity of the eco-environmental water requirement is 555 millions m3, the minimum quantity of the eco-environmental water requirement with the assuring probability of 75% is 289 millions m3 and the minimum quantity of the eco-environmental water requirement with the assuring probability of 95% is 354 millions m3.

Estimation methods of eco-environmental water requirements: Case study

Supplying water to the ecological environment with certain quantity and quality is significant for the protection of diversity and the realization of sustainable development. The conception and connotation of eco-environmental water requirements, including the definition of the conception, the composition and characteristics of eco-environmental water requirements, are evaluated in this paper. The classification and estimation methods of eco-environmental water requirements are then proposed. On the basis of the study on the Huang-Huai-Hai Area, the present water use, the minimum and suitable water requirement are estimated and the corresponding water shortage is also calculated. According to the interrelated programs, the eco-environmental water requirements in the coming years (2010, 2030, 2050) are estimated. The result indicates that the minimum and suitable eco-environmental water requirements fluctuate with the differences of function setting and the referential standard of water resources, and so as the water shortage. Moreover, the study indicates that the minimum eco-environmental water requirement of the study area ranges from 2.84×10 10 m3 to 1.02×10 11 m 3 , the suitable water requirement ranges from 6.45×10 10 m 3 to 1.78×10 11 m 3 , the water shortage ranges from 9.1×10 9 m 3 to 2.16×10 10 m 3 under the minimum water requirement, and it is from 3.07×10 10 m 3 to 7.53×10 10 m 3 under the suitable water requirement. According to the different values of the water shortage, the water priority can be allocated. The ranges of the eco-environmental water requirements in the three coming years (2010, 2030, 2050) are 4.49×10 10 m 3 -1.73×10 11 m 3 , 5.99×10m 3 -2.09×10 11 m 3 , and 7.44×10 10 m 3 -2.52×10 11 m 3 , respectively.