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1.
李晓东  宋开山  闫守刚 《湖泊科学》2022,34(4):1294-1307
半干旱内陆地区的湖泊湿地是一种特殊的生态系统,季节和年际时间尺度上的湖泊水文变化对湖泊湿地生态结构和功能有着重要影响.近20年来,月亮泡湖泊湿地经历了自然和人为因素共同作用下的水文波动过程.为了实现大尺度地表生态年内/年际变化检测,更好地了解湖泊年际水淹范围及其水淹频次对内陆湖滨湿地生态的影响,基于1994—2018年Landsat TM/OLI影像数据(30 m),首先,计算提取月亮泡的年际水体信息和水淹频次,进而获取湖泊年际淹没范围.其次,采用综合生态指数变化检测法提取生态信息,选取3个标准观测年(1995、2006、2016年),从年内变化和年际变化视角分级评价了研究区生态变化,并分析了水淹频次与湿地生态变化的关系.最终,现有研究表明:湖泊年际水淹区主要分布在月亮泡的北侧与西侧尾闾,月亮泡湖泊湿地北侧的年际水淹频次更为显著.湖泊面积的扩展与自然湿地的减少是月亮泡水淹区域的主要变化类型.在这种变化情况下,研究区水体指数累积量的增加与植被指数累积量的衰减成为显著的生态变化特点.月亮泡湖泊年际水淹频次在一定时间和空间上影响着水淹区域的植被生产能力,水淹的低频波动是研究区植被累积量增加的关键因子.因此,在湿地生态恢复与管理过程中,维持合理的水文波动,恢复月亮泡北侧与西侧沼泽湿地是该区域内生态保护的核心措施.  相似文献   

2.
Abstract

The operation of the Three Gorges Reservoir (TGR) is an important driver of the recent hydrological changes in the lowlands of Dongting Lake, China. Nevertheless, there has been no convincing study on the quantitative effects of the TGR regulation on the wetland inundation process. Here, the temporal and spatial patterns of the response of wetland inundation in Dongting Lake to the TGR regulation are addressed in detail using a two-dimensional hydrodynamic model, which can accurately reproduce the flooding and drying processes. The results show that temporal patterns of wetland inundation are altered by the TGR regulation, especially in the water pre-releasing period (May to early June) and the water storing period (late September to November). Spatially heterogeneous effects are also observed in Dongting Lake. These findings can help us to take measures at an early stage to effectively deal with the possible adverse effects of the normal operation of the TGR on Dongting Lake.

Editor D. Koutsoyiannis; Associate editor A. Porporato

Citation Lai, X., Jiang, J., and Huang, Q., 2013. Effects of the normal operation of Three Gorges Reservoir on wetland inundation in Dongting Lake, China: a modelling study. Hydrological Sciences Journal, 58 (7), 1467–1477.  相似文献   

3.
Abstract

The hydrology of water-dependent ecosystems around the world has been altered as a result of flow regulation and extraction for a variety of purposes including agricultural and urban water supply. The flow regime of the Murray-Darling Basin in Australia is no exception, with attendant impacts on the health of the environment. Restoration of parts of the flow regime is a key feature of environmental flow delivery. However, environmental flow delivery in a system that is managed primarily to provide a secure and stable supply for irrigation presents challenges for managers seeking to return more natural flow variability in line with ecosystem requirements. The institutional arrangements governing releases of water from storage can influence the ability of managers to respond to natural cues, such as naturally rising flows in a river. As such, the legal and governance aspects of environmental flow delivery are likely to be important influences on the outcomes achieved.
Editor Z.W. Kundzewicz; Guest editor M. Acreman

Citation Banks, S.A. and Docker, B.B., 2014. Delivering environmental flows in the Murray-Darling Basin (Australia)—legal and governance aspects. Hydrological Sciences Journal, 59 (3–4), 688–699.  相似文献   

4.
《水文科学杂志》2012,57(1):33-56
ABSTRACT

Riparian depressional wetlands (haors) in the Upper Meghna River Basin of Bangladesh are invaluable agricultural resources. They are completely flooded between June and November and planted with Boro rice when floodwater recedes in December. However, early harvest period (April/May) floods frequently damage ripening rice. A calibrated/validated Soil and Water Assessment Tool for riparian wetland (SWATrw) model is perturbed with bias free (using an improved quantile mapping approach) climate projections from 17 general circulation models (GCMs) for the period 2031–2050. Projected mean annual rainfall increases (200–500 mm or 7–10%). However, during the harvest period lower rainfall (21–75%) and higher evapotranspiration (1–8%) reduces river discharge (5–18%) and wetland inundation (inundation fraction declines of 0.005–0.14). Flooding risk for Boro rice consequently declines (rationalized flood risk reductions of 0.02–0.12). However, the loss of cultivable land (15.3%) to increases in permanent haor inundation represents a major threat to regional food security.  相似文献   

5.
ABSTRACT

The impact of climate change on hydrology and water salinity of a valuable coastal wetland (Anzali) in northern Iran is assessed using daily precipitation and temperature data from 19 models of Coupled Model Inter-comparison Project Phase 5. The daily data are transiently downscaled using the Long Ashton Research Station Weather Generator to three climatic stations. The temperature is projected to increase by +1.6, +1.9 and +2.7°C and precipitation to decrease by 10.4%, 12.8% and 12.2% under representative concentration pathway (RCP) scenarios RCP2.6, RCP4.5 and RCP8.5, respectively. The wetland hydrology and water salinity are assessed using the water balance approach and mixing equation, respectively. The upstream river flow modelled by the Soil and Water Assessment Tool is projected to reduce by up to 18%, leading to reductions in wetland volume (154 × 106 m3), area (57.47 km2) and depth (2.77 m) by 34%, 21.1% and 20.2%, respectively, under climate change, while the mean annual total dissolved solids (1675 mg/L) would increase by 49%. The reduced volume and raised salinity may affect the wetland ecology.  相似文献   

6.
Z. Jia  S. Tang  W. Luo  Y. Hai 《水文科学杂志》2013,58(16):2946-2956
ABSTRACT

Constructed wetlands can be used for reducing nonpoint-source pollution and providing ecological services in a watershed. This paper presents a field monitoring study on water quality improvement in constructed wetlands of five cells in series. The wetland system covers 59.9 ha, or 0.08% of the watershed area; it diverts 7.3 million m3 (hm3) water (or 4.3% annual flow) from a degraded river. The results showed that the hydraulic retention times (HRT) of the five cells ranged from 5 to 15 days, 18.4% inflow was lost to seepage and increased evapotranspiration (ET) in the wetlands; the wetlands retained 99.1% total suspended solids (TSS), 60.9% total phosphorus (TP), and 54.4% total nitrogen (TN) from the inflow. Major reductions of TSS and TP were observed in the first two large cells that occupied 57% of the total wetland area. The smaller cells did not show advantages over the bigger ones in pollutant retention as reported in some studies. Although significant water quality benefit can be achieved by the constructed wetlands, the increased water loss may be a concern, particularly in dry regions.
EDITOR Z.W. Kundzewicz; ASSOCIATE EDITOR T. Okruszko  相似文献   

7.
Abstract

In many of the world’s river basins, the water resources are over-allocated and/or highly modified, access to good quality water is limited or competitive and aquatic ecosystems are degraded. The decline in aquatic ecosystems can impact on human well-being by reducing the ecosystem services provided by healthy rivers, wetlands and floodplains. Basin water resources management requires the determination of water allocation among competing stakeholders including the environment, social needs and economic development. Traditionally, this determination occurred on a volumetric basis to meet basin productivity goals. However, it is difficult to address environmental goals in such a framework, because environmental condition is rarely considered in productivity goals, and short-term variations in river flow may be the most important driver of aquatic ecosystem health. Manipulation of flows to achieve desired outcomes for public supply, food and energy has been implemented for many years. More recently, manipulating flows to achieve ecological outcomes has been proposed. However, the complexity of determining the required flow regimes and the interdependencies between stakeholder outcomes has restricted the implementation of environmental flows as a core component of Integrated Water Resources Management (IWRM). We demonstrate through case studies of the Rhône and Thames river basins in Europe, the Colorado River basin in North America and the Murray-Darling basin in Australia the limitations of traditional environmental flow strategies in integrated water resources management. An alternative ecosystem approach can provide a framework for implementation of environmental flows in basin water resources management, as demonstrated by management of the Pangani River basin in Africa. An ecosystem approach in IWRM leads to management for agreed triple-bottom-line outcomes, rather than productivity or ecological outcomes alone. We recommend that environmental flow management should take on the principles of an ecosystem approach and form an integral part of IWRM.

Editor D. Koutsoyiannis

Citation Overton, I.C., Smith, D.M., Dalton J., Barchiesi S., Acreman M.C., Stromberg, J.C., and Kirby, J.M., 2014. Implementing environmental flows in integrated water resources management and the ecosystem approach. Hydrological Sciences Journal, 59 (3–4), 860–877.  相似文献   

8.
《水文科学杂志》2013,58(6):1006-1020
Abstract

This paper aims to compare the shift in frequency distribution and skill of seasonal climate forecasting of both streamflow and rainfall in eastern Australia based on the Southern Oscillation Index (SOI) Phase system. Recent advances in seasonal forecasting of climate variables have highlighted opportunities for improving decision making in natural resources management. Forecasting of rainfall probabilities for different regions in Australia is available, but the use of similar forecasts for water resource supply has not been developed. The use of streamflow forecasts may provide better information for decision-making in irrigation supply and flow management for improved ecological outcomes. To examine the relative efficacy of seasonal forecasting of streamflow and rainfall, the shift in probability distributions and the forecast skill were evaluated using the Wilcoxon rank-sum test and the linear error in probability space (LEPS) skill score, respectively, at three river gauging stations in the Border Rivers Catchment of the Murray-Darling Basin in eastern Australia. A comparison of rainfall and streamflow distributions confirms higher statistical significance in the shift of streamflow distribution than that in rainfall distribution. Moreover, streamflow distribution showed greater skill of forecasting with 0–3 month lead time, compared to rainfall distribution.  相似文献   

9.
周期性的淹没或出露是洪泛型湖泊湿地的重要物理特征,湖泊湿地的淹没动态对其生态过程有显著影响。三峡工程运行以来,鄱阳湖湿地淹没动态发生了显著变化并引发了剧烈生态效应,而目前研究尚未对后三峡工程时代的鄱阳湖淹没动态演变进行系统量化,也制约了对其驱动下湖泊湿地生态系统演变原因与机制的了解。鉴于此,本研究结合水文站实测数据与遥感观测资料,以淹没开始时间、淹没结束时间以及淹没历时3个变量共同表征湖泊湿地淹没动态,从站点及全湖尺度分别对三峡工程运行后鄱阳湖湿地淹没动态的变化趋势、量级及显著性进行定量分析。结果表明:(1)2000—2020年间,鄱阳湖湿地淹没开始时间在64%的湖区被推迟,推迟速率约为1.10天/年;仅在入江水道及碟形湖小幅提前,且提前趋势并不显著;(2)鄱阳湖湿地淹没结束时间在72%的湖区显著提前,提前速率约为1.46天/年;仅在有闸控工程的碟形湖因延迟泄水而有所延迟;(3)受淹没开始时间推迟而结束时间提前的影响,鄱阳湖湿地淹没历时在70%的湖区显著缩短,缩短速率约为2.19天/年,而在有闸控工程的碟形湖则有所延长。本文从站点与全湖尺度分别给出了基于实测而非模型模拟的鄱阳湖淹没动态...  相似文献   

10.
Abstract

Effective policies to protect groundwater-dependent ecosystems require robust methods to determine the environmental flows and levels required to support species and processes. Frameworks to support groundwater management must incorporate the relationships between hydrology and species and ecological processes. These hydro-ecological relationships can be used to develop quantitative, measurable thresholds that are sensitive to changes in groundwater quantity. Here we provide a case study from a group of fens in central Oregon, USA, that are used for cattle watering, but also support numerous sensitive species. We developed quantitative relationships between the position of the water table and wetland indicator plant species and the process of peat development, to propose groundwater withdrawal thresholds. A maximum depth to water table of –0.9 to –34.8 cm for fen plants and –16.6 to –32.2 cm for peat accretion can be tolerated in these wetlands. Defining hydro-ecological relationships as thresholds can support management decisions.
Editor D. Koutsoyiannis; Guest editor M. Acreman

Citation Aldous, A.R. and Bach, L.B., 2014. Hydro-ecology of groundwater-dependent ecosystems: applying basic science to groundwater management. Hydrological Sciences Journal, 59 (3–4), 530–544.  相似文献   

11.
Abstract

The Hai River Basin (HRB) is a heavily irrigated region encompassing the North China Plain (NCP) in northeast China. In the last decades, continuous lowering of groundwater levels had been reported in the NCP. This study used data from the Gravity Recovery and Climate Experiment (GRACE) and in situ measurements to quantify recent changes in groundwater storage from 2003 to 2012. The signal from GRACE observations highlight a sharp decline in the deep subsurface water stores (deep unsaturated zone and groundwater systems) up to a rate of 17.0 ± 4.3 mm year-1 between 2003 and 2012 over the HRB, equal to a volumetric loss of 5.5 ± 1.4 km3 year-1. This result shows good consistency with in situ observations of groundwater hydraulic heads compiled from monitoring bores, and emphasizes GRACE’s ability to monitor large-scale groundwater storage variations. Results from GRACE also provide an independent assessment of the effectiveness of water saving programmes that have been implemented by the government so far. Our study indicates that groundwater overdrawal is still prevalent and the dominant factor for the persistent loss in groundwater storage over the HRB/NCP; the current groundwater consumption pattern is far beyond the natural recharge ability in groundwater system.
Editor D. Koutsoyiannis; Associate editor T. Wagener  相似文献   

12.
High Arctic wetlands, though limited in occurrence, are an important ecological niche, providing the major vegetated areas in an arid and cold polar desert environment. These wetlands are often found as patches in the barren landscape. At a few locales which may be ice-wedge polygonal grounds, glacial terrain and zones of recent coastal uplift, wetland occurrence can become extensive, forming a mosaic that comprises patches of different wetland types. Reliable water supply during the thawed season is a deciding factor in wetland sustainability. The sources include meltwater from late-lying snowbanks, localized ground water discharge, streamflow, inundation by lakes and the sea, and for some ice-wedge wetlands, ground-ice melt. Different types of wetlands have their own characteristics, and peat accumulation or diatom depositions are common. The peat cover insulates the wetland from summer heating and encourages permafrost aggradation, with the feedback that a shallow frost table reduces the moisture storage capacity in a thinly thawed layer, which becomes easily saturated. All the wetlands studied have high calcium content since they are formed on carbonate terrain. Coastal wetlands have high salt concentration while snowmelt and ground-ice melt provides dilution. The sustainability of High Arctic wetlands is predicated upon water supply exceeding the losses to evaporation and lateral drainage. Disturbances due to natural causes such as climatic variations, geomorphic changes, or human-induced drainage, can reduce inundation opportunities or increase outflow. Then, the water table drops, the vegetation changes and the peat degrades, leading to the detriment of the wetlands.  相似文献   

13.
林雨荘  焦自美 《湖泊科学》2005,17(3):269-274
河川是一个复杂的生态系统,河川主支干道即为系统中的主要动脉,各种物质循环、能量流动、物种讯息传输,均依赖河川水系为之.但因人类迁入活动及过度利用水资源,干扰了水的自然循环,土壤与微生物的自然演化,生物的迁徙与演替平衡等.且目前河川治理大多以取水、防洪为优先,忽略了景观生态原则在河川中的作用,致使城市与水环境关系日益疏离,物种的栖息地逐渐被破坏.本研究以台湾北部淡水河流域为例,探讨河川流域中之景观生态功能,并将景观生态原则纳入流域治理的综合目标之一,研拟可持续发展的策略.  相似文献   

14.
太湖流域湖荡湿地影响着整个流域生态系统的健康运转,是湖泊水体与陆地之间的过渡带,对周边城市的生态环境起到重要的净化调节作用,对太湖流域湖荡湿地生态系统健康进行评价,有利于湖荡湿地的科学管理,从而实现湖荡湿地资源的可持续利用.本文选择太湖流域11个典型的湖荡湿地为研究对象,于2012-2015年开展周年湿地观测季度调查.利用主客观组合赋权方法,结合太湖流域自然条件和社会功能,提出了基于生态可修复性指标的太湖流域湖荡湿地生态系统健康评价体系和方法.结果表明:太湖流域湖荡湿地中生态系统健康等级为优的占27.27%,分别是傀儡湖、尚湖和钱资荡;生态系统健康等级为良的湖荡湿地占9.09%,为长荡湖;中等生态系统健康水平的湖荡湿地居多,占36.36%,分别是阳澄湖、昆承湖、元荡和淀山湖;生态系统健康等级为差的湖荡湿地占18.18%,分别是滆湖、澄湖和宜兴三氿.本研究建立的湖泊生态健康评估体系和湖泊生态健康评价结果对太湖流域湖荡湿地的后续有效管理具有重要的现实意义.  相似文献   

15.
Abstract

Pakistan has suffered a devastating flood disaster in 2010. In the Kabul River basin (92 605 km2), large-scale riverine and flash floods caused destructive damage with more than 1100 casualties. This study analysed rainfall–runoff and inundation in the Kabul River basin with a newly developed model that simulates the processes of rainfall–runoff and inundation simultaneously based on two-dimensional diffusion wave equations. The simulation results showed a good agreement with an inundation map produced based on MODIS for large-scale riverine flooding. In addition, the simulation identified flash flood-affected areas, which were confirmed to be severely damaged based on a housing damage distribution map. Since the model is designed to be used even immediately after a disaster, it can be a useful tool for analysing large-scale flooding and to provide supplemental information to agencies for relief operations.

Editor Z.W. Kundzewicz

Citation Sayama, T., Ozawa, G., Kawakami, T., Nabesaka, S. and Fukami, K., 2012. Rainfall–runoff–inundation analysis of the 2010 Pakistan flood in the Kabul River basin. Hydrological Sciences Journal, 57 (2), 298–312.  相似文献   

16.
Abstract

The Dead Sea is shrinking as its water level drops at the alarming rate of about 1 m year-1. The Dead Sea is important to the economies of Israel and Jordan due to the extracted minerals (primarily potassium, also magnesium and bromide). It is also central to regional tourism. It is the lowest place on Earth and its endorheic, saline basin attracts international research in various disciplines. Additional to the Lower Jordan River, the discharge of which has been decreased to a small fraction of its original value, fresh to brackish springs are the main source of water to the rapidly dwindling Dead Sea. Although the existence of these springs has been known for decades, until recently estimates of spring water discharge into the Dead Sea were scarce. In this study, we developed a methodology of water discharge estimation for channels incising into a lacustrine bed using remotely sensed data and a single hydraulic geometry variable, water-surface width. Based on calibration of over 400 in situ measurements and simultaneous hydrometric data from aerial images, width–discharge rating curves were established, tested, and found suitable (r2 = 0.92, p = 0.001) for the estimation of water discharge, with ±5% uncertainty. Furthermore, we used these relationships to estimate retrospectively the temporal changes in water discharge of seven main channels traceable in historical aerial images. The reconstructed trend reveals a major (63%) reduction in average freshwater inflow between 1990 and 2006. Our results maximize the use of water-surface width information from aerial imagery, and suggest applicability to areas experiencing rapid exposure of sea/lake bed and consequent access difficulties in in situ discharge monitoring.
Editor Z.W. Kundzewicz  相似文献   

17.
Abstract

The increasing water demand is a concern affecting many regions in the Mediterranean Basin. To overcome this situation rim countries resorted during the last decades to a massive mobilization of their water resources, often resulting in excessive water exploitation. In such a context, understanding the effects of present recharge and aquifer salinization is crucial for correct water management. Understanding the present hydrogeological situation of coastal plains requires the knowledge of both their past morphologic conditions and their recent geological evolution. Within this framework, this paper presents a review of water related problems in the Mediterranean Basin. It suggests a conceptual model for groundwater resources in Mediterranean coastal plains, deriving from the present and past recharge processes. Special attention is paid to providing a better understanding of climate change impacts on water quantity and quality, and conservation of ecological diversity.

Citation Re, V. & Zuppi, G. M. (2011) Influence of precipitation and deep saline groundwater on the hydrological systems of Mediterranean coastal plains: a general overview. Hydrol. Sci. J. 56(6), 966–980.  相似文献   

18.
This work applies ecological footprint analysis to establish the framework of a carrying capacity model for a national park. The model estimates changes in ecological footprint and biocapacity indicators for Taroko National Park (Taiwan) from 2002 to 2011. The findings indicate that: (1) In the past 10 years, the biocapacity status of Taroko National Park has remained within the environmental capacity; however, the per-capita ecological reserve decreased by 73.38 % between 2002 and 2011, from 0.085010 global hectares to 0.022633 global hectares. Evaluation of the ecological footprint intensity index reveals that the park has maintained a level 1 status, the highest ecological security level; (2) Linear estimation undertaken in the study predicts that when the ecological footprint intensity index reaches 0.5—when the ecological security level falls from level 1 (good) to level 2 (fair)—the critical tourist-carrying capacity would be 3,380,351 visitors per year, or 1.18 times the number of tourists in 2011. Furthermore, when the ecological footprint intensity index reaches 0.8—when the ecological security falls to level 3 (poor)—the critical tourist-carrying capacity would be 5,408,561 visitors per year, or 1.88 times the number of tourists in 2011. This work adopted the ecological footprint method and the threshold ecological footprint intensity index value to estimate the critical number of tourists for the sustainable biocapacity of Taroko National Park. The results are intended to serve as a reference for national park administrators to develop policies on tourist carrying capacity.  相似文献   

19.
Water agreements between Mexico and the United States have been crucial to preserving and restoring the Colorado River Delta's wetlands. Nowadays, increased water demand and climate change in the Colorado River Basin could threaten the conservation of the Ciénega de Santa Clara, a 4709 ha coastal wetland at the Sonoran Desert's edge. The international Ramsar convention recognizes the Ciénega de Santa Clara ecosystem for providing vital ecological services, including habitat for endemic, endangered, and migratory species. The hydrology of this wetland has not been completely understood since the 2010–2011 trial run of the Yuma Desalting Plant. Therefore, this study was conducted to identify and quantify the hydrological elements essential for the conservation of this wetland, under three scenarios: (a) normal inflow conditions of the water source – the Wellton-Mohawk canal; (b) inflow reductions, and; (c) an increase of temperature due to global warming. Water and mass balances estimates were conducted every month during 2014–2015; in situ measurements of inflows were carried out on Southern International Boundary in Wellton-Mohawk canal, the Riíto Drain, groundwater, and precipitation: evapotranspiration outputs were estimated using local weather stations and Penman-Monteith formulations. Temperature increases were based on the Intergovernmental Panel on Climate Change projections for the next 100 years. Results showed disconnection in the surface flow of water from the wetland to the adjacent Gulf of California. This behaviour was observed mainly in the summer months in the three scenarios. The disconnections reduced the wetland area and water storage. The hydrological functionality of the Ciénega de Santa Clara wetland depends on the water supply from the Wellton-Mohawk canal, with a minimum continuous discharge of 5.10 m3 s−1 during the summer months.  相似文献   

20.
Abstract

A three-dimensional Environmental Fluid Dynamics Code model was developed for a 17-km segment of the Mobile River, Alabama, USA. The model external forcing factors include river inflows from upstream, tides from downstream, and atmospheric conditions. The model was calibrated against measured water levels, velocities, and temperatures from 26 April to 29 August 2011. The Nash-Sutcliffe coefficients for water levels were greater than 0.94 and for water temperatures ranged from 0.88 to 0.99. The calibrated model was extended approximately 13 km upstream for simulating unsteady flow, dye, and temperature distributions in the Mobile River under different upstream inflows and downstream harmonic tides. Velocity profiles and distributions of flow, dye, and temperature at various locations were analyzed and show that flow recirculation could only occur under small inflow (50 m3 s-1) when downstream tides control the flow pattern in the Mobile River. The model results reveal complex interactions among discharges from a power plant, inflows, and tides.
Editor D. Koutsoyiannis; Associate editor D. Yang  相似文献   

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