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951.
AbstractTo enable assessment of risks of water management to riparian ecosystems at a regional scale, we developed a quantile-regression model of abundance of broadleaf cottonwoods (Populus deltoides and P. fremontii) as a function of flood flow attenuation. To test whether this model was transferrable to narrowleaf cottonwood (Populus angustifolia), we measured narrowleaf abundance along 39 river reaches in northwestern Colorado, USA. The model performed well for narrowleaf in all 32 reaches where reservoir storage was <75% of mean annual flow. Field data did not fit the model at four of seven reaches where reservoir storage was >90% of mean annual flow. In these four reaches, narrowleaf was abundant despite peak flow attenuation of 45–61%. Poor model performance in these four reaches may be explained in part by a pulse of narrowleaf cottonwood expansion as a response to channel narrowing and in part by differences between narrowleaf and broadleaf cottonwood response to floods and drought.
Editor Z.W. Kundzewicz; Guest editor M. AcremanCitation Wilding, T.K., Sanderson, J.S., Merritt, D.M., Rood, S.B., and Poff, N.L., 2014. Riparian responses to reduced flood flows: comparing and contrasting narrowleaf and broadleaf cottonwoods. Hydrological Sciences Journal, 59 (3–4), 605–617. 相似文献
952.
AbstractMaintaining and restoring the ecological integrity of floodplains remains a priority for many Australian federal and state government agencies. The Murray-Darling Basin Authority (MDBA) introduced the Proposed Basin Plan 2012, the Australian government’s latest basin-scale water planning instrument to promote a healthy, working river system. The proposal seeks to limit surface water (consumptive) use to 10 873 GL year-1 on a long-term average. The controversy prompted by this proposed reduction has underscored a need for rigorous and transparent modelling of ecological benefits. In this paper, we investigate the likely ecological outcomes of the proposal for Yanga National Park, one of the most significant environmental assets in the Murray-Darling Basin, using a decision support system. Our results indicate that the proposal will increase the inundation extent with a 33% (or 7000 ha) increase in median flood. The increase in inundation would improve the hydrological conditions in most wetlands in terms of the frequency and duration of events and inter-flood dry periods and enhance the habitat quality for a range of biota, though benefits are not distributed evenly across the wetland.
Editor D. Koutsoyiannis; Guest editor M. AcremanCitation Wen, L. and Saintilan, N., 2014. Linking local ecological outcomes with basin-wide water planning: a case study of Yanga National Park, an important Australian inland forested wetland. Hydrological Sciences Journal, 59 (3–4), 904–915. 相似文献
953.
AbstractThe strong wet and dry seasons of tropical monsoon hydrology in India necessitate development of storage and flow diversion schemes for utilization of water to meet various social and economic needs. However, the river valley schemes may cause adverse flow-related impacts due to storage, flow diversion, tunnelling and spoil disposal. There may be critical reaches in which altered flows are not able to sustain the river channel ecology and riparian environment that existed prior to implementation of the storage and diversion schemes. In the past, environmental flows in India have usually been understood as the minimum flow to be released downstream from a dam as compensation for riparian rights, without considering the impacts on the river ecosystem. Rivers in India have been significantly influenced by anthropogenic activities over the past 60 years and have great social and religious significance to the vast population. This paper explores various aspects of past, present and future environmental flow assessment (EFA) in India highlighted by case studies from rivers across the nation. It demonstrates that multidisciplinary studies requiring expertise from a range of fields are needed for EFA, and that environmental flows are necessary for aquatic ecosystems to remain in a healthy state and for the sustainable use of water resources. The major focus areas for the development of EFA research in India are the creation of a shareable database for hydrological, ecological and socioeconomic data, developing hydrology–ecology relationships, evaluation of ecosystem services, addressing pollution due to anthropogenic activities and promotion of research on EFA. At the same time, efforts will be needed to develop new methods or refine existing methods for India.
Editor D. Koutsoyiannis; Guest editor M. AcremanCitation Jain, S.K. and Kumar, P., 2014. Environmental flows in India: towards sustainable water management. Hydrological Sciences Journal, 59 (3–4), 751–769. 相似文献
954.
The Canadian Rocky Mountain headwaters support the water resource systems of the Canadian Prairies. Significant variations in natural headwater contributions have been observed due to warming climate. Projecting future natural headwater flows under climate change effects, however, has large uncertainty. First, there are difficulties in climate modeling and downscaling in alpine regions. Second, streamflow modeling in mountainous areas is extremely challenging. There is therefore a need to understand the effects of uncertainty in the natural inflow regime, and in particular how this translates into uncertainty in representing the state and the outflow of water resource systems. Considering the Oldman River basin in Alberta, Canada, we synthesized different inflow regimes based on site/inter-site properties of the historical inflow regime. The water resources system was then conditioned on the synthesized inflow regimes to identify the mechanisms of error propagation from the headwater streamflows to the water allocations. The results show that the response of the water resource system to the uncertainty in the generated inflow regime depends on the system state, flow condition and the component of interest. Generally, the response of the reservoirs to the uncertainty in the estimated inflow regime is more significant in dry years, in particular during low flow conditions. The response at the system outlet is rather different, as the propagation of the headwater uncertainty is more significant during high flow conditions. Also, similar inflow estimates in terms of error and uncertainty may result in different error and uncertainty estimates in the simulated outflows; therefore, lower bias and uncertainty in estimating the regional inflow regime does not necessarily mean lower bias and uncertainty in simulating the streamflow at the outlet of the system. Our results provide improved understanding of uncertainty propagation through complex water resource systems, but also portray the need for better climate and hydrological modeling in the Rocky Mountains for improved water management in the Canadian Prairies, particularly in the face of uncertain climate futures. This will be crucial if the natural headwater inflows decline and/or the system faces drought conditions. 相似文献
955.
The objective of this study was to determine the changing characteristics of soil surface roughness under different rainfall intensities and examine the interaction between soil surface roughness and different water erosion processes. Four artificial management practices (raking cropland, artificial hoeing, artificial digging, and contour tillage) were used according to the local agriculture customs of the Loess Plateau of China to simulate different types of soil surface roughness, using an additional smooth slope for comparison purposes. A total of 20 rainfall simulation experiments were conducted in five 1 m by 2 m boxes under two rainfall intensities (0.68 and 1.50 mm min?1) on a 15° slope. During splash erosion, soil surface roughness decreased in all treatments except raking cropland and smooth baseline under rainfall intensity of 0.68 mm min?1, while increasing for all treatments except smooth baseline under rainfall intensity of 1.50 mm min?1. During sheet erosion, soil surface roughness decreased for all treatments except hoeing cropland under rainfall intensity of 0.68 mm min?1. However, soil surface roughness increased for the artificial hoeing and raking cropland under rainfall intensity of 1.50 mm min?1. Soil surface roughness has a control effect on sheet erosion for different treatments under two rainfall intensities. For rill erosion, soil surface roughness increased for raking cropland and artificial hoeing treatments, and soil surface roughness decreased for artificial digging and the contour tillage treatments under two rainfall intensities. Under rainfall intensity of 0.68 mm min?1, the critical soil surface roughness was 0.706 cm for the resistance control of runoff and sediment yield. Under rainfall intensity of 1.50 mm min?1, the critical soil surface roughness was 1.633 cm for the resistance control of runoff, while the critical soil surface roughness was 0.706 cm for the resistance control of sediment yield. These findings have important implications for clarifying the erosive nature of soil surface roughness and harnessing sloped farmland. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
956.
957.
为了科学评价地震台站的管理工作,全面提高其管理效益,利用层次分析(AHP)法,对地震台站各项工作进行综合考量,设计地震台站管理测评系统,并结合安徽省地震台站实例,验证该测评系统的适用性. 相似文献
958.
利用Java语言,使用Microsoft SQL Server 2005数据库,利用MyEclipse工具研发地震仪器设备管理系统.使用该系统进行台站仪器设备信息管理,便于保存、查询、更新信息,实现数据资料的完整、准确、长期保存,工作效率增加. 相似文献
959.
Yun GAO 《地下水科学与工程》2014,2(1):21-28
This report chooses Clarence City Council as the coastal jurisdiction and analyzes its planning processes and instruments for its potential to build resilience to climate change impacts on the coast. In the first part, it introduces the change of Australia’s climate and consequences of climate change. Based on analysis of sea level rise, inundation and erosion risk, it shows climate change has impacts on Clarence coastal areas in Tasmania. This paper shows the three key elements for successful coastal management (retreat, accommodation and protection) and discusses the factors that impede resilience. Finally, there are some recommendations that may be helpful for climate change impacts and local council 相似文献
960.
CHEN Qu 《地下水科学与工程》2014,2(2):54-61
Climate change issues has been discussed and argued for decades. It has been widely recognized that climate change will bring more serious issues to environment vulnerable areas than other areas. Southern Australia is one of the typical examples of vulnerable areas where water deficiency is enhanced by climate change. Although, this area has been successfully adapted with drought environment for decades, those shortcomings of strategies are highlighted by climate change events. In the interests of sustainable water management, Southern Australia’s experiences on possible anticipatory adaptation approaches, especially on mitigation of risks and costs of drought could be expected to provide recommendations to planning and management actions in the future 相似文献