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61.
Natech accidents at industrial plants are an emerging risk with possibly serious consequences. For the mitigation of natech risk, authorities need to identify natech prone areas in a systematic manner. In order to facilitate probabilistic natech risk mapping, a unified methodology was developed that is based on the estimation of on-site natural hazard parameters, determination of damage probabilities of plant units, and assessment of probability and severity of possibly triggered natech events. The methodology was implemented as an on-line, extensible risk assessment and mapping software framework called RAPID-N, which allows rapid local and regional natech risk assessment and mapping with minimal data input. RAPID-N features an innovative data estimation framework to complete missing input data, such as on-site natural hazard parameters and plant unit characteristics. The framework is also used for damage assessment and natech consequence analysis, and allows easy modification of input parameters, dynamic generation of consequence models according to data availability, and extension of models by adding new equations or substituting existing ones with alternatives. Results are presented as summary reports and interactive risk maps, which can be used for land-use and emergency planning purposes by using scenario hazards, or for rapid natech consequence assessment following actual disasters. As proof of concept, the framework provides a custom implementation of the U.S. EPA's RMP Guidance for Offsite Consequence Analysis methodology to perform natech consequence analysis and includes comprehensive data for earthquakes. It is readily extendible to other natural hazards and more comprehensive risk assessment methods. 相似文献
62.
Ken M. Fritz Elisabeth Hagenbuch Ellen D'Amico Molly Reif Parker J. Wigington Jr. Scott G. Leibowitz Randy L. Comeleo Joseph L. Ebersole Tracie‐Lynn Nadeau 《Journal of the American Water Resources Association》2013,49(4):867-882
Supreme Court cases have questioned if jurisdiction under the Clean Water Act extends to water bodies such as streams without year‐round flow. Headwater streams are central to this issue because many periodically dry, and because little is known about their influence on navigable waters. An accurate account of the extent and flow permanence of headwater streams is critical to estimating downstream contributions. We compared the extent and permanence of headwater streams from two field surveys with values from databases and maps. The first used data from 29 headwater streams in nine U.S. forests, whereas the second had data from 178 headwater streams in Oregon. Synthetic networks developed from the nine‐forest survey indicated that 33 to 93% of the channel lacked year‐round flow. Seven of the nine forests were predicted to have >200% more channel length than portrayed in the high‐resolution National Hydrography Dataset (NHD). The NHD and topographic map classifications of permanence agreed with ~50% of the field determinations across ~300 headwater sites. Classification agreement with the field determinations generally increased with increasing resolution. However, the flow classification on soil maps only agreed with ~30% of the field determination despite depicting greater channel extent than other maps. Maps that include streams regardless of permanence and size will aid regulatory decisions and are fundamental to improving water quality monitoring and models. 相似文献
63.
Eva Rose Peter Nagel Daniel Haag-Wackernagel 《Behavioral ecology and sociobiology》2006,60(2):242-254
Feral pigeons are descendants of wild rock pigeons that have adapted to the urban habitat. They have partially conserved the foraging behaviour of their wild ancestors (flights to agricultural areas) but have also developed new habits. Previous studies on the foraging strategies of feral pigeons have given various results, e.g. maximum distances reached by the pigeons (measured in a straight line from the resting places) differed between 0.3–0.5 km and 18–25 km. This study focuses on the spatio-temporal activity of feral pigeons in the urban habitat. We equipped 80 free-living feral pigeons from Basel, Switzerland with GPS receivers. We found three different foraging strategies for pigeons in Basel: (1) in the streets, squares and parks near the home loft, (2) in agricultural areas surrounding the city, (3) on docks and railway lines in harbours. The maximum distance reached by a pigeon was 5.29 km. More than 32% of the pigeons remained within 0.3 km of the home lofts and only 7.5% flew distances of more than 2 km. Females covered significantly longer distances than males, preferring to fly to more abundant and predictable food sources. Temporal activity patterns showed to be influenced by sex, breeding state and season. In contrast to wild rock pigeons and to feral pigeons in other cities, pigeons in Basel showed a clear bimodal activity pattern for breeding birds only. The differences between our results and those of other studies seem to be partly method-dependent, as the GPS-technique allows to record the pigeons’ localisations continuously in contrast to other methods. Other differences might be due to different kinds of food supply in the various cities. Our study shows that feral pigeons have individual foraging strategies and are flexible enough to adapt to different urban environments.Electronic supplementary material Supplementary material is available for this article at 相似文献
64.
以“3S”技术及其集成为代表的现代测绘技术在解决我国矿区存在的资源浪费及环境污染问题中具有重要的应用,本文对此进行了探讨。 相似文献
65.
中国地表水酸化敏感性的区划 总被引:9,自引:0,他引:9
地表水体的酸化与集水区的许多环境因子密切相关,如土壤对酸的缓冲能力、基岩中和酸沉降的能力以及土地利用方式等.其中,土壤的抗酸化能力是关键因素.因此可以根据集水区土壤、基岩和土地利用方式等信息来评估地表水在不同流量下发生酸化的可能性.本研究成功地应用已有资料和数据得到了我国地表水对酸沉降的敏感性等级,并绘制了地表水酸化敏感性区划图.结果表明,我国大部分地表水对酸化并不敏感.极易酸化和较易酸化的地表水主要分布在东北的北部地区,占所有国土面积的2.67%,是该地区强酸性漂灰土、酸性母岩和针叶林植被共同作用的结果.对酸化敏感性为中级和低级,即不易酸化的地表水主要分布在东北暗棕壤地区和南方富铝土区域,占所有国土面积的15.2%.其余82.11%国土面积上的地表水对酸化不敏感,完全不可能发生酸化.北方地区主要是由于土壤的强缓冲能力,而在南方,石灰质土壤以及耕作农田的广泛分布是最重要因素.南方重酸雨区由于土壤对酸化并不很敏感,因此在短期内不会出现大面积水体酸化现象.由于东北近年来频频出现酸雨,因此东北的酸沉降必须及早防治,以免出现大面积酸化水体. 相似文献
66.
We created a measure to help comprehend population vulnerability to potential flooding and excessive heat events using health, built environment and social factors. Through principal component analysis (PCA), we created non‐weighted sum index scores of literature‐reviewed social and built environment characteristics. We created baseline poor health measures using 1999–2005 age‐adjusted cardiovascular and combined diabetes and hypertension mortality rates to correspond with social–built environment indices. We mapped US Census block groups by linked age‐adjusted mortality and a PCA‐created social–built environment index. The goal was to measure flooding and excessive heat event vulnerability as proxies for population vulnerability to climate change for Travis County, Texas. This assessment identified communities where baseline poor health, social marginalisation and built environmental impediments intersected. Such assessments may assist targeted interventions and improve emergency preparedness in identified vulnerable communities, while fostering resilience through the focus of climate change adaptation policies at the local level. 相似文献
67.
Jan Atle Knutsen Halvor Knutsen Eli Rinde Hartvig Christie Torjan Bodvin Einar Dahl 《Ambio》2010,39(2):148-158
For many years, the planning and management of terrestrial areas has been supported by a detailed knowledge of the distribution
of habitats and their associated species. However, the detailed mapping of biological resources in extent coastal areas, such
as the Norwegian coastal zone, is unrealistic due to its enormous coastline. Here, we present a useful and feasible approach
and a set of simple, cost-effective methods which are suitable for providing a broad-scale overview of marine habitats and
fish resources. This approach was developed in conjunction with a pioneer study conducted along the southern coast of the
Skagerrak, where we combined knowledge gathered from local fishermen with scientific knowledge of important species and nature
types to establish a coastal sea mapping program. GIS modeling tools were used in both the mapping program and to integrate
local and scientific knowledge into digital maps made available to local area management. This multi-faceted approach, which
combines local knowledge and scientific methods, provides valuable information with respect to marine biodiversity, and has
been used extensively by local environmental management. 相似文献
68.
69.
Stafford JD Reinecke KJ Kaminski RM Gerard PD 《Journal of environmental management》2006,78(4):353-361
Large-scale sample surveys to estimate abundance and distribution of organisms and their habitats are increasingly important in ecological studies. Multi-stage sampling (MSS) is especially suited to large-scale surveys because of the natural clustering of resources. To illustrate an application, we: (1) designed a stratified MSS to estimate late autumn abundance (kg/ha) of rice seeds in harvested fields as food for waterfowl wintering in the Mississippi Alluvial Valley (MAV); (2) investigated options for improving the MSS design; and (3) compared statistical and cost efficiency of MSS to simulated simple random sampling (SRS). During 2000-2002, we sampled 25-35 landowners per year, 1 or 2 fields per landowner per year, and measured seed mass in 10 soil cores collected within each field. Analysis of variance components and costs for each stage of the survey design indicated that collecting 10 soil cores per field was near the optimum of 11-15, whereas sampling >1 field per landowner provided few benefits because data from fields within landowners were highly correlated. Coefficients of variation (CV) of annual estimates of rice abundance ranged from 0.23 to 0.31 and were limited by variation among landowners and the number of landowners sampled. Design effects representing the statistical efficiency of MSS relative to SRS ranged from 3.2 to 9.0, and simulations indicated SRS would cost, on average, 1.4 times more than MSS because clustering of sample units in MSS decreased travel costs. We recommend MSS as a potential sampling strategy for large-scale natural resource surveys and specifically for future surveys of the availability of rice as food for waterfowl in the MAV and similar areas. 相似文献
70.
Conservation Value of Remnant Riparian Forest Corridors of Varying Quality for Amazonian Birds and Mammals 总被引:3,自引:0,他引:3
Abstract: Forest corridors are often considered the main instrument with which to offset the effects of habitat loss and fragmentation. Brazilian forestry legislation requires that all riparian zones on private landholdings be maintained as permanent reserves and sets fixed minimum widths of riparian forest buffers to be retained alongside rivers and perennial streams. We investigated the effects of corridor width and degradation status of 37 riparian forest sites (including 24 corridors connected to large source-forest patches, 8 unconnected forest corridors, and 5 control riparian zones embedded within continuous forest patches) on bird and mammal species richness in a hyper-fragmented forest landscape surrounding Alta Floresta, Mato Grosso, Brazil. We used point-count and track-sampling methodology, coupled with an intensive forest-quality assessment that combined satellite imagery and ground truthed data. Vertebrate use of corridors was highly species-specific, but broad trends emerged depending on species life histories and their sensitivity to disturbance. Narrow and/or highly disturbed riparian corridors retained only a depauperate vertebrate assemblage that was typical of deforested habitats, whereas wide, well-preserved corridors retained a nearly complete species assemblage. Restriction of livestock movement along riparian buffers and their exclusion from key areas alongside deforested streams would permit corridor regeneration and facilitate restoration of connectivity . 相似文献