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1.
从水资源量供需平衡的角度出发,判别城市发展与自然水系统的可持续性。基于生态足迹理论,构建了水生态足迹与水生态承载力模型,并以广西南宁市为例,对2004-2013年的水资源可持续程度进行定量分析。结果发现：（1）南宁市历年水资源用量处于盈余状态;（2）淡水资源生态足迹所占比例较大,且与人口增长和经济发展有密切关系;（3）万元GDP生态曲线的不断降低表明南宁市水资源利用效率逐步提高。研究结果表明,南宁市水资源符合可持续利用的原则。 相似文献
2.
Nineteen ecologically relevant streamflow characteristics were estimated using published rainfall–runoff and regional regression models for six sites with observed daily streamflow records in Kentucky. The regional regression model produced median estimates closer to the observed median for all but two characteristics. The variability of predictions from both models was generally less than the observed variability. The variability of the predictions from the rainfall–runoff model was greater than that from the regional regression model for all but three characteristics. Eight characteristics predicted by the rainfall–runoff model display positive or negative bias across all six sites; biases are not as pronounced for the regional regression model. Results suggest that a rainfall–runoff model calibrated on a single characteristic is less likely to perform well as a predictor of a range of other characteristics (flow regime) when compared with a regional regression model calibrated individually on multiple characteristics used to represent the flow regime. Poor model performance may misrepresent hydrologic conditions, potentially distorting the perceived risk of ecological degradation. Without prior selection of streamflow characteristics, targeted calibration, and error quantification, the widespread application of general hydrologic models to ecological flow studies is problematic. Published 2012. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
3.
为评价区域水环境承载与经济社会荷载之间的相对关系,采用水环境承载的可持续性评价指标体系来进行分析。该指标体系为指数-指标-变量的金字塔信息模式,分1个指数、6个分类指标、36个表征变量。根据保定市的地域特点与发展情况,选取1995~2004年的统计资料,采用常规加权平均综合评价法、模糊综合评价法分别计算了保定市1995~2004年的水环境承载度。结果分析表明,保定市的水环境承载度尽管处于较低水平(可持续承载度<0.6),但总体而言,水环境可持续承载度呈现出逐年增大的趋势,增加的幅度大约为0.01/a,表明总体趋势是向好的方向发展。局部地区的一些指标仍有远离可持续承载的趋势,需要采取相应的措施与对策。 相似文献
4.
Natural flood regimes provide a wide array of important ecological functions. Our goal is to assess the hydrologic impact of dams on flood flows throughout the United States. Regional regression models of the median annual 1‐day maximum flow were developed as a function of natural watershed characteristics, dam storage, and population density. Most of the regressions have adjusted R2 values in excess of 0.80, and overall the models covered 78% of the area of the continental U.S. Alteration of flood flows is present in every region of the country, and is more severe west of the Mississippi and especially in the southern Great Plains, desert Southwest, and northern California. The percent of U.S. rivers with greater than a 25% reduction in the median annual flood is 55% for large rivers, 25% for medium rivers, and 10% for small rivers. The majority of freshwater ecoregions in the country have at least 10% of their rivers with 25% or greater alteration in all three river size classes. A simple model based on the ratio of dam storage to mean annual runoff was developed for assessing alteration in ungauged rivers, and was found to be generally useful for classifying rivers into categories of potential alteration. Overall, we document the alteration of natural flood flows across the U.S. in more detail than has been previously accomplished, and demonstrate the efficacy of multivariate regional regression models and other indicators for assessing hydrologic alteration. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
5.
Elizabeth P. Anderson Sue Jackson Rebecca E. Tharme Michael Douglas Joseph E. Flotemersch Margreet Zwarteveen Chicu Lokgariwar Mariana Montoya Alaka Wali Gail T. Tipa Timothy D. Jardine Julian D. Olden Lin Cheng John Conallin Barbara Cosens Chris Dickens Dustin Garrick David Groenfeldt Jane Kabogo Dirk J. Roux Albert Ruhi Angela H. Arthington 《Wiley Interdisciplinary Reviews: Water》2019,6(6)
River flows connect people, places, and other forms of life, inspiring and sustaining diverse cultural beliefs, values, and ways of life. The concept of environmental flows provides a framework for improving understanding of relationships between river flows and people, and for supporting those that are mutually beneficial. Nevertheless, most approaches to determining environmental flows remain grounded in the biophysical sciences. The newly revised Brisbane Declaration and Global Action Agenda on Environmental Flows (2018) represents a new phase in environmental flow science and an opportunity to better consider the co‐constitution of river flows, ecosystems, and society, and to more explicitly incorporate these relationships into river management. We synthesize understanding of relationships between people and rivers as conceived under the renewed definition of environmental flows. We present case studies from Honduras, India, Canada, New Zealand, and Australia that illustrate multidisciplinary, collaborative efforts where recognizing and meeting diverse flow needs of human populations was central to establishing environmental flow recommendations. We also review a small body of literature to highlight examples of the diversity and interdependencies of human‐flow relationships—such as the linkages between river flow and human well‐being, spiritual needs, cultural identity, and sense of place—that are typically overlooked when environmental flows are assessed and negotiated. Finally, we call for scientists and water managers to recognize the diversity of ways of knowing, relating to, and utilizing rivers, and to place this recognition at the center of future environmental flow assessments. This article is categorized under:
- Water and Life > Conservation, Management, and Awareness
- Human Water > Water Governance
- Human Water > Water as Imagined and Represented
6.
Groundwater is a critically important source of water for river, wetland, lake, and terrestrial ecosystems, yet most frameworks for assessing environmental flows have ignored or not explicitly included the potential impacts of groundwater pumping on environmental flows. After assessing the processes and existing policies for protecting streamflow depletion from groundwater pumping, we argue that a new groundwater presumptive standard is critical as a placeholder to protect environmental flows in rivers lacking detailed assessments. We thus extend the previous presumptive standard to groundwater pumping, a different and important driver of changes to streamflow. We suggest that “high levels of ecological protection will be provided if groundwater pumping decreases monthly natural baseflow by less than 10% through time.” The presumptive standard is intended to be a critical placeholder only where detailed scientific assessments of environmental flow needs cannot be undertaken in the near term. We also suggest a new metric, the environmental flow response time, that allows water managers to quantify the timescales of the impacts of groundwater pumping on the loss or gain of environmental flows. 相似文献
7.
A good understanding of the natural flow regime plays an important role in many hydrological studies. Also important in such studies is the quantification of environmental flows. This study focuses on flow metrics that best describe the natural flow regime and the hydrological characteristics for rivers in New Brunswick (Canada) as well as quantifying environment flows for these rivers. New Brunswick rivers have a mean annual flow (MAF) of approximately 23 L s?1 km?2, which is also reflective of the water availability. The frequency analysis showed that low flows (T = 2–50 years, where T is the recurrence interval) were all below the 10% MAF. Environmental flow methods based on the MAF and flow duration analysis (median flow) showed good regional regression equations. However, flow duration methods showed high variability especially at flows between Q80 and Q100. Flow targets based on the 25% MAF, Q50 and 70% Q50 were used to estimate environmental flows, particularly during low‐flow periods (winter and summer). Results showed that the 70% Q50 method should be used with caution in summer as this method provided flows in the range of 15–16% of MAF. Other methods provided environmental flows higher than 15% MAF, thus, providing better flow protection for aquatic habitat. When comparing water availability for off‐stream use (river flow–environmental flow), different parts of New Brunswick were found to be deficient in flows (i.e., river flows less than environment flows—no extractable water) during the summer and winter low‐flow periods. 相似文献
8.
Determination of water resources management thresholds, such as conservation releases, passby flows, and water availability limits, is a contemporary challenge facing water resources managers. With recent advancements in environmental flow science, including the ecological limits of hydrologic alteration (ELOHA) framework, environmental flow standards can be developed for a variety of stream types throughout a particular region or watershed. Environmental flow standards typically cover the entire natural flow regime, including low‐flow, seasonal‐flow (medium), and high‐flow components. However, it can be difficult for water resources managers to directly apply these standards to establish practical management thresholds. This study proposes a novel approach to assessing water capacity based on ELOHA environmental flow standards. The procedure entails iterative simulations to identify withdrawal limits for gaged streams and regional regression analysis to predict withdrawal limits for ungaged streams. The approach was applied for 63 reference gages with long‐term, continuous, minimally altered, daily streamflow records within the Susquehanna River basin. The results of the investigation demonstrate that the approach can be used to assess water capacity from gaged and ungaged streams via iterative withdrawal simulations and regional regression analysis respectively. The regression equation developed through analysis of the reference gages has an adjusted R‐square value of 0.96 and a standard error of 27%. Determination of a water capacity value, based on a suite of environmental flow standards, provides water resources managers with a valuable tool for informing the establishment of water resources management thresholds. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
9.
Peter A. Gell 《河流研究与利用》2020,36(4):620-629
The floodplain wetlands of the southern Murray Darling Basin (MDB) have been subject to the impacts of catchment and water resource development for more than a century. Their current degraded state is attributed to the regulation of the rivers and abstraction of water volume for irrigation. The MDB Plan is to return at least 2,750 Gl of mean annual flow to the system to restore the condition of waterways. Considerable recent investment in infrastructure enables water to be released into the basin's floodplain wetlands. The proposed watering regime is underpinned by modelling that suggests that, before regulation, overbank flows would have occurred regularly as discharge peaked in winter and spring. Sediment cores have been extracted from over 50 floodplain wetlands of the southern Murray Basin. Those from several, large meander wavelength billabongs extend for 1,000–5,000 years suggesting that these sites were permanently inundated over that time. Others extend to ~200 years and are presumed not to have accumulated sediment until more recently. The records of most wetlands, however, only extend to the onset of river regulation in the 1920s, suggesting that before then they were not inundated for sufficient duration for net accumulation to occur. Preserved diatoms suggest that the shallow, plant‐dominated wetlands of the past have transitioned to deep, turbid water systems today. As rivers are identified as a source of sediment to wetlands, less regular inundation, rather than more, is a viable option in restoring the ecological function of these floodplain wetlands and in slowing sediment infill. 相似文献
10.
在云南城市环境建设项目管理的实践基础上,对参与式的环境治理模式进行初步探讨,对云南城市环境建设项目的主要利益相关群体及其主体性进行浅析,提出在云南城市环境建设项目中开展项目目标群体参与、利用公众力量开展城市环境治理的有关建议。 相似文献
11.
水环境容量计算在工程中的应用 总被引：1，自引：0，他引：1
做好现状和规划状态下的生态需水估算,有利于水利规划,有利于生态环境调控与管理,更有利于水资源的优化配置。本文用不同方法分析了三亚市南山创意新城河网的水环境容量,使该项目在促进经济发展和满足防洪排涝、水资源开发利用的同时,又保护与修复了生态环境。 相似文献
12.
Charles van Rees J. Michael Reed 《Journal of Contemporary Water Research & Education》2015,155(1):28-42
Contemporary water management strategies call for the inclusion of ecological research in the decision‐making process and emphasize environmentally sustainable management solutions. Most ecological information used in water management shares two problematic characteristics; 1) simplistic, phenomenological approaches and aggregated data that may not properly describe system behavior, and 2) a “zero‐sum” perspective treating ecological water needs as constraints to management. We argue that the newly devised Water Diplomacy Framework (WDF) can help overcome these shortcomings. We also provide a simple and intuitive method for integrating ecological factors into the WDF. We suggest that treating ecological phenomena as “surrogate stakeholders” in water negotiations increases opportunities for discovering mutual‐gains solutions and encourages a hypothesis‐based approach to research on the ecology of water management. By differentiating between the “positions” and “interests” of ecological stakeholder surrogates, decision‐makers can make greater use of the potential added value of ecosystem services in water management and avoid costly misunderstandings of the behavior of relevant ecological systems. We outline how the WDF can be applied to better integrate ecological factors into water management, and show how our approach could create synergies between endangered waterbird conservation and sustainable water management on the island of Oahu, Hawaii. 相似文献
13.
Experimental floods, generated downstream of dams, are used to recover specific bio‐geomorphic functions in regulated rivers. Studies of the effects of experimental floods vary in their objective, location, and the hydrological and bio‐geomorphic variables used to quantify recovery. Measurements of geomorphic change are required to guide future release strategies. The focus of this study was to determine if a large experimental flood in the Snowy River Australia, could promote geomorphic recovery of the river channel downstream of Jindabyne Dam following 35 years of flow regulation. The objectives of the release were to deepen, widen, and increase channel capacity and coarsen the riverbed substratum in the Jindabyne Gorge and Dalgety Uplands sections of the Snowy River. Data from the release were compared with that of a natural flood event that occurred after the experimental flow event. Both events showed channel adjustments and a degree of geomorphic recovery, but this varied between the two river sections. Marked channel adjustments occurred in the Dalgety Uplands reach following both the experimental and natural flood event and in the Jindabyne Gorge section following the natural flood event. Geomorphic changes were related to the hydrological character of each flood event. The number of flood peaks, the sequence of peaks, the flood duration, and the total energy expenditure differed markedly between the two events, and these four flood hydrological characteristics explained the greater geomorphic recovery associated with the natural flood event in the Jindabyne Gorge. No clear hydro‐geomorphic relationship was derived for channel change in the Dalgety Uplands where existing morphological constraints limit flood effectiveness. 相似文献
14.
Sarah M. Yarnell Eric D. Stein J. Angus Webb Theodore Grantham Rob A. Lusardi Julie Zimmerman Ryan A. Peek Belize A. Lane Jeanette Howard Samuel Sandoval‐Solis 《河流研究与利用》2020,36(2):318-324
The science and practice of environmental flows have advanced significantly over the last several decades. Most environmental flow approaches require quantifying the relationships between hydrologic change and biologic response, but this can be challenging to determine and implement due to high data requirements, limited transferability, and the abundance of hydrologic metrics available for evaluation. We suggest that a functional flows approach, focusing on elements of the natural flow regime known to sustain important ecosystem processes, offers a pathway for linking understanding of ecosystem processes with discrete, quantifiable measures of the flow regime for a broad range of native taxa and assemblages. Functional flow components can be identified as distinct aspects of the annual hydrograph that support key biophysical processes, such as wet season flood flows or spring recession flows, and then quantified by flow metrics, such as 5% exceedance flow or daily percent decrease in flow, respectively. By selecting a discrete set of flow metrics that measure key functional flow components, the spatial and temporal complexity of flow regimes can be managed in a holistic manner supportive of multiple ecological processes and native aquatic species requirements. We provide an overview of the functional flows approach to selecting a defined set of flow metrics and illustrate its application in two seasonally variable stream systems. We further discuss how a functional flows approach can be utilized as a conceptual model both within and outside of existing environmental flow frameworks to guide consideration of ecological processes when designing prescribed flow regimes. 相似文献
15.
Early attempts to gauge streams were used by George Baxter in 1961 to propose a pioneering scheme for deriving and allocating water for what today may be recognized as environmental flows in the United Kingdom, but the approach was not accepted into practice. A fundamental concern was the quality of river flow data. Stream gauging was advanced by the 1963 Water Resources Act, and prior to this, the allocation of water resources to compensation flows below dams was based on the basic principle of one third of the reliable yield, estimated using rainfall data. Despite the increased availability of river flow data since the 1970s, it is suggested that low‐flow data quality has severely constrained the management and allocation of water resources and remains so today. Today, pressures and demands on water resources are increasing, but the accuracy of low‐flow measurement is still hindering the operational determination and implementation of environmentally robust, seasonally variable environmental flows. Successful river regulation and restoration relate to a complex suite of public policy questions and given uncertainty over the quality of low‐flow data, transparent, pragmatic decisions about societal allocations of water need to be made. 相似文献
16.
The Lancang River, located in the upper reach of the Mekong River, has attracted worldwide attention for the large‐scale development of hydropower on its main stream, In the paper, taking Manwan dam as a case study, we adopt emergy analysis method for three ratio indices, i.e. the emergy yield ratio (EYR), environmental loading ratio (ELR) and ecosystem index for sustainability (EIS), to analyse the beneficial contribution of dam construction and operation (DCP) to regional social system, and environmental pressure as well as sustainability of river ecosystem (reservoir area and downstream channel). Different from traditional researches, the loss for ecosystem service of terrestrial ecosystem around reservoir (STER) as a significant cost is integrated into holistic analysis for ecological effect of Manwan dam construction (DC). The result show that the emergy yield of river ecosystem after Manwan DC is equal to 4.58 × 1021 sej/yr, of which the majority is from electricity generation (4.52 × 1021 sej/yr), i.e. 98.7% of the total emergy yield. The gross emergy cost of the ecosystem in the Manwan reservoir area is 6.75 × 1020 sej/yr, with the primary one being derived from sediment deposition (3.72 × 1020 sej/yr), which accounts for 55.11% of the total emergy cost. The loss of STER (1.71 × 1020 sej/yr) follows and accounts for 25.33% of the total emergy cost. We conclude that no matter whether sediments and the loss of STER are included or not, EYR of present system after DC is higher than that of former system without DC, indicating that hydropower exploitation plays an important role in improvement of the emergy yield of regional system. However, the sediment deposition and loss of STER would result in a much higher environmental pressure (increased by 44.53 times) and a lower sustainability (the index decreased by 14.43 times) to the present system. Especially, this is an underestimated conclusion due to the limitation of data available without considering the emergy loss of ecological heritage and hydrological process as well as river continuum. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
17.
The aim of this study was to identify whether environmental flows released into two lowland rivers (the Glenelg and Wimmera Rivers, western Victoria, Australia) during the spring to autumn period had successfully ameliorated the negative effects of multiple human impacts. Macroinvertebrates and a range of physico‐chemical variables were sampled from three reaches in each river. Both rivers were sampled during three environmental release seasons with average‐sized releases (1997–1998, 1998–1999 and 2001–2002) and two drought seasons with limited releases (1999–2000 and 2000–2001). The effects of releasing average‐sized environmental flows on macroinvertebrates and physico‐chemical variables were assessed by comparison with data from the two drought seasons. For the Glenelg River, data from a reference season prior to the release of environmental flows (1995–1996) was also compared to data from the five environmental flow seasons. Multivariate analyses revealed four pieces of evidence indicating that the release of environmental flows effectively slowed the process of environmental degradation in the Glenelg River but not in the Wimmera River: (1) the magnitude of the river discharge was dependent on the size of environmental flow releases; (2) in the Wimmera River, water quality deteriorated markedly during the two drought seasons and correlated strongly with macroinvertebrate assemblage structure, but this was not observed in the Glenelg River; (3) the taxonomic composition of the macroinvertebrate assemblages among contrasting flow release seasons reflected the severe deterioration in water quality of the Wimmera River; (4) despite two drought seasons with minimal environmental flow releases, the macroinvertebrate assemblage in the Glenelg River did not differ from the average‐release seasons, nor did it return to a pre‐environmental flows condition. Therefore, it appears that environmental flow releases did sustain the macroinvertebrate assemblage and maintain reasonable water quality in the Glenelg River. However, in the Wimmera River, release volumes were too small to maintain low salinities and were associated with marked changes in the macroinvertebrate assemblage. Therefore, there are multiple lines of evidence that environmental flow releases of sufficient magnitude may slow the process of degradation in a regulated lowland river. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
18.
Recent water reform in Australia has focused on seeking to balance the needs of the environment and consumptive users through improved flow regimes. This is in response to declining ecological conditions, exacerbated by drought and the threat of climate change particularly in the Murray-Darling Basin. A programme of environmental flows integrated through multiple governance layers and managed by an independent federal-government entity operating in the water market on behalf of the environment has been established to help rectify the decline. While a challenge for this new entity involves determining when to release, trade or carry over water in storage so as to maximize environmental outcomes, early results point to real environmental gains within a highly regulated and diverse river system. 相似文献
19.
Drought refuges enable the biota of intermittent streams to survive dry periods, but their roles in sustaining algal assemblage structure and productivity are not known. This study determined the importance of two types of drought refuge (dry biofilm, permanent pools) for benthic algal regrowth in four intermittent streams in the Grampians National Park, Victoria, Australia. Dry biofilm was removed by scrubbing randomly chosen stones from two dry riffles in each of two streams with permanent pools and two streams without permanent pools. Algae were sampled from scrubbed and control stones at one, six and sixteen weeks after flow resumed. Removal of dry algal biofilm resulted in lower algal densities on stones from both stream types, and scrubbed stones had similar densities of algae after one week, regardless of the presence or absence of permanent pools. Algal density on stones exposed to both refuge types was more than an order of magnitude higher than the density on stones exposed to either one or neither refuge. The effects of biofilm removal on algal density were still apparent after six weeks of flow and assemblage composition differed between streams with and without permanent pools. Dry biofilm was an important drought refuge for algae in both stream types, but epilithic algal density in streams with permanent pools developed more rapidly than streams that were completely dry over summer. Loss of permanent pools from intermittent streams due to water abstraction may substantially reduce algal productivity after flow resumes, which may limit the supply of autochthonous carbon. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
20.
Mauro Carolli Francesca Gelmini Stefano Pellegrini Micaela Deriu Guido Zolezzi 《河流研究与利用》2021,37(1):17-32
We discuss the prioritization of river reaches to be selected for restoration measures under the constraints of financial resource limitation. We propose and apply a simple approach based on the quantification of major hydro‐morphological alterations and the critical comparison with locally proposed restoration actions. The available hydro‐morphological and ecological data for the approach do not go beyond the requirements posed by the implementation of the EU Water Framework and Floods Directives. We describe an example that refers to a heavily regulated Alpine river (Sarca River, NE Italy). The results indicate hydropower facilities as a key source of hydrological alteration, with sediment retention and grade control structures on lateral tributaries playing an additional relevant role in reducing sediment supply. The frequency and duration of sediment‐transporting floods have dramatically decreased, and the bed sediment composition has been markedly altered and become highly compacted. Habitat improvement has been achieved after the implementation of minimum environmental flows. The comparison between the results of the hydro‐morphological indicators and the locally proposed restoration actions highlights that reaches with lower degree of hydro‐morphological alterations do not coincide with the areas chosen for the locally planned actions, which often miss considerations of the relevant spatial scales. In a context of limited available financial resources and data compared to other flagship river restoration projects in the European Alps, the present work suggests viable options for the choice of target restoration reaches. 相似文献