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381.
Project River Recovery: Restoration of Braided Gravel-Bed River Habitat in New Zealand’s High Country 总被引:1,自引:1,他引:0
Caruso BS 《Environmental management》2006,37(6):840-861
Ecological restoration is increasingly becoming a primary component of broader environmental and water resources management
programs throughout the world. The New Zealand Department of Conservation implemented Project River Recovery (PRR) in 1991
to restore unique braided gravel-bed river and wetland habitat in the Upper Waitaki Basin in New Zealand’s high country of
the South Island, which has been severely impacted by hydroelectric power development. These braided rivers are highly dynamic,
diverse, and globally important ecosystems and provide critical habitat to numerous native wading and shore bird species,
including several threatened species such as the black stilt. The objective of this study was to review and summarize PRR
after more than 10 years of implementation to provide information and transfer knowledge to other nations and restoration
programs. Site visits were conducted, discussions were held with key project staff, and project reports and related literature
were reviewed. Primary components of the program include pest plant and animal control, wetland construction and enhancement,
a significant research and monitoring component, and public awareness. The study found that PRR is an excellent example of
an ecological restoration program focusing on conserving and restoring unique habitat for threatened native bird species,
but that also includes several secondary objectives. Transfer of knowledge from PRR could benefit ecological restoration programs
in other parts of the world, particularly riverine floodplain and braided river restoration. PRR could achieve even greater
success with expanded goals, additional resources, and increased integration of science with management, especially broader
consideration of hydrologic and geomorphologic effects and restoration opportunities. 相似文献
382.
A GIS Approach to Model Sediment Reduction Susceptibility of Mixed Sand and Gravel Beaches 总被引:3,自引:0,他引:3
The morphological form of mixed sand and gravel beaches is distinct, and the process/response system and complex dynamics
of these beaches are not well understood. Process response models developed for pure sand or gravel beaches cannot be directly
applied to these beaches. The Canterbury Bight coastline is apparently abundantly supplied with sediments from large rivers
and coastal alluvial cliffs, but a large part of this coastline is experiencing long-term erosion. Sediment budget models
provide little evidence to suggest sediments are stored within this system. Current sediment budget models inadequately quantify
and account for the processes responsible for the patterns of erosion and accretion of this coastline. We outline a new method
to extrapolate from laboratory experiments to the field using a geographical information system approach to model sediment
reduction susceptibility for the Canterbury Bight. Sediment samples from ten representative sites were tumbled in a concrete
mixer for an equivalent distance of 40 km. From the textural mixture and weight loss over 40 km tumbling, we applied regression
techniques to generate a predictive equation for Sediment Reduction Susceptibility (SRS). We used Inverse Distance Weighting
(IDW) to extrapolate the results from fifty-five sites with data on textural sediment composition to field locations with
no data along the Canterbury Bight, creating a continuous sediment reductions susceptibility surface. Isolines of regular
SRS intervals were then derived from the continuous surface to create a contour map of sediment reductions susceptibility
for the Canterbury Bight. Results highlighted the variability in SRS along this coastline. 相似文献
383.
基于模糊马尔可夫链状原理的灾害预测——以新亚欧大陆桥新疆段为例 总被引:7,自引:2,他引:5
根据新亚欧大陆桥新疆段近40年灾害统计资料,基于模糊马尔可夫链状预测的方法与原理,通过模糊状态的划分和模糊运算,根据隶属度最大原则,确定所属的状态,对新疆段受损区段数进行了预测,预测准确率为75%,取得了预期的效果。 相似文献
384.
新亚欧大陆桥新疆段风沙流活动特性及停积规律 总被引:8,自引:0,他引:8
通过对新亚欧大陆桥新疆段不同区段风沙流实测资料的分析,探讨了砾漠区和沙漠区的风沙流活动特性及其停积规律.研究表明,风沙流随风力条件、下垫面状况而变化,其搬运能力与风力大小呈正相关;高程与含沙量(%)对数尺度之间具有良好的线性关系,含沙量随高度增加成指数规律衰减;砾漠区沙粒粗大,在2.0m以下高程其含量随高度增大而明显增大,沙漠区风沙流物质成分以细粒为主(占71%);物质运动以跃移为主,易在低路堤边坡,半填、半挖路基和浅路堑处沉降积沙;在风沙流运动方向与线路走向的夹角<30°时,积沙厚度较小,而当其>45°时,积沙量随夹角增大呈明显增多的趋势. 相似文献
385.
Jonathan M. Gallimore Barbara B. Brown Carol M. Werner 《Journal of environmental psychology》2011,31(2):184-191
We assessed environmental and perceptual correlates of walking and walkability for fifth graders from three communities attending two schools: A new urban/LEED-ND pilot community, mixed, and standard suburban community. Irvine-Minnesota Inventory (IMI) walkability audits showed that new urban blocks provided more traffic safety, pleasurability, crime safety, density, and diversity. New urban routes offered greater traffic safety, accessibility, pleasurability, crime safety, and diversity, but suburban routes had greater housing density, net of controls (parental education, rooms in the home, home ownership, parent preference for child to walk to school). Parents and children perceived new urban routes to be more walkable and children walked more when they lived on more walkable routes. The suburban hierarchical street design exposed children to varied traffic safety conditions by funneling their walks from cul-de-sacs to arterials. The new urban routes to a centrally located school passed by pleasant open spaces, suggesting how community organization can create better walking conditions. 相似文献
386.
387.
388.
Frank Ackerman 《Local Environment》2013,18(2):223-229
Waste management has at least five types of impacts on climate change, attributable to: (1) landfill methane emissions; (2) reduction in industrial energy use and emissions due to recycling and waste reduction; (3) energy recovery from waste; (4) carbon sequestration in forests due to decreased demand for virgin paper; and (5) energy used in long-distance transport of waste: A recent USEPA study provides estimates of overall per-tonne greenhouse gas reductions due to recycling. Plausible calculations using these estimates suggest that countries such as the US or Australia could realise substantial greenhouse gas reductions through increased recycling, particularly of paper. 相似文献
389.
390.
Information about the net benefits of land degradation treatment is required at the relevant management level, such as regional, local or site-specific, to assist decision makers in the allocation of funds to soil conservation. In this paper, estimates of regional opportunity costs of erosion and costs of treatment are used to derive benefit-cost ratios to assess the profitability of gully erosion treatment for localities in the wheat-sheep zone of New South Wales. These results are then used to develop site-specific models which predict benefit-cost ratios of treatment from land attributes including gully length, slope, soil type and land use. These predictive models form the basis of a rapid appraisal method to aid soil conservation decisions. 相似文献