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501.
Kari E. Gunson Anthony P. Clevenger Adam T. Ford John A. Bissonette Amanda Hardy 《Environmental management》2009,44(2):268-277
Wildlife-vehicle collisions (WVCs) pose a significant safety and conservation concern in areas where high-traffic roads are
situated adjacent to wildlife habitat. Improving transportation safety, accurately planning highway mitigation, and identifying
key habitat linkage areas may all depend on the quality of WVC data collection. Two common approaches to describe the location
of WVCs are spatially accurate data derived from global positioning systems (GPS) or vehicle odometer measurements and less
accurate road-marker data derived from reference points (e.g., mile-markers or landmarks) along the roadside. In addition,
there are two common variable types used to predict WVC locations: (1) field-derived, site-specific measurements and (2) geographic
information system (GIS)-derived information. It is unclear whether these different approaches produce similar results when
attempting to identify and explain the location of WVCs. Our first objective was to determine and compare the spatial error
found in road-marker data (in our case the closest mile-marker) and landmark-referenced data. Our second objective was to
evaluate the performance of models explaining high- and low-probability WVC locations, using congruent, spatially accurate
(<3-m) and road-marker (<800-m) response variables in combination with field- and GIS-derived explanatory variables. Our WVC
data sets were comprised of ungulate collisions and were located along five major roads in the central Canadian Rocky Mountains.
We found that spatial error (mean ± SD) was higher for WVC data referenced to nearby landmarks (516 ± 808 m) than for data
referenced to the closest mile-marker data (401 ± 219 m). The top-performing model using the spatially accurate WVC locations
contained all explanatory variable types, whereas GIS-derived variables were only influential in the best road-marker model
and the spatially accurate reduced model. Our study showed that spatial error and sample size, using road-marker data for
ungulate species, are important to consider for model output interpretation, which will impact the appropriate scale on which
to apply modeling results. Using road-marker references <1.6 km or GPS-derived data locations may represent an optimal compromise
between data acquisition costs and analytical performance.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
502.
Research has found that human-caused noise can detract from the quality of the visitor experience in national parks and related
areas. Moreover, impacts to the visitor experience can be managed by formulating indicators and standards of quality as suggested
in park and outdoor recreation management frameworks, such as Visitor Experience and Resource Protection (VERP), as developed
by the U.S. National Park Service. The research reported in this article supports the formulation of indicators and standards
of quality for human-caused noise at Muir Woods National Monument, California. Phase I identified potential indicators of
quality for the soundscape of Muir Woods. A visitor “listening exercise” was conducted, where respondents identified natural
and human-caused sounds heard in the park and rated the degree to which each sound was “pleasing” or “annoying.” Certain visitor-caused
sounds such as groups talking were heard by most respondents and were rated as annoying, suggesting that these sounds may
be a good indicator of quality. Loud groups were heard by few people but were rated as highly annoying, whereas wind and water
were heard by most visitors and were rated as highly pleasing. Phase II measured standards of quality for visitor-caused noise.
Visitors were presented with a series of 30-second audio clips representing increasing amounts of visitor-caused sound in
the park. Respondents were asked to rate the acceptability of each audio clip on a survey. Findings suggest a threshold at
which visitor-caused sound is judged to be unacceptable, and is therefore considered as noise. A parallel program of sound
monitoring in the park found that current levels of visitor-caused sound sometimes violate this threshold. Study findings
provide an empirical basis to help formulate noise-related indicators and standards of quality in parks and related areas. 相似文献
503.
Anti‐desertification planning in Iran operates at the national level through the Five Year Development Plans, the National Plan to Combat Desertification — a long‐running scheme for which the Forest, Rangeland and Watershed Management Organisation (FRWO) is responsible — and the recently developed National Action Programme to Combat Desertification (the NAP). The Iranian NAP was formulated following the country's ratification of the United Nations Convention to Combat Desertification and drew heavily on the experience, expertise and collaboration of personnel in FRWO. Development and implementation of the NAP has had major policy impacts in Iran in the two main areas of generating cross‐sectoral cooperation between government instruments at the national planning level and by community participation in local projects to combat desertification. Documenting the evolution of cross‐sectoral and participatory approaches to desertification in Iran shows that the NAP provided impetus towards a transformation of previous procedures, a policy impact that is continuing to generate change. 相似文献
504.
"十一五"期间,秦皇岛市的环境保护取得了明显的成绩,"十二五"期间,秦皇岛市的环境保护工作仍然面临严峻挑战。因此,应该遵循环境优先、不欠新账、强化治理、机制创新、注重规划衔接等原则,高水平编制秦皇岛市"十二五"环境保护规划,重点落实编制秦皇岛市主体功能区划,深入推进水污染综合治理,建立完善环境保护考核机制,加强环境保护监督管理,明确环境保护重点项目,提高规划的可操作性。 相似文献
505.
506.
Podlaski R 《Environmental monitoring and assessment》2007,135(1-3):339-351
Tree damage, gauged by the amount of defoliation, is one of the basic criteria used to determine treatments for protected
and economic forests. Monitoring should include an assessment of the degree of tree damage in different spatial scales. Therefore,
in addition to the commonly applied large-area methods, small-area methods should be used. The aim of the paper is to present
the results of the accuracy assessment of a small-area method, proposed by Podlaski (2005) [Podlaski, R. (2005). Inventory of the degree of tree defoliation in small areas. Forest Ecology and Management, 215, 361–377], for monitoring the degree of tree damage. The degree of tree damage was shown in sub-blocks P3 of the system of information on natural environment (SINUS). To estimate the spatial distribution of the degree of tree defoliation,
survey sampling, based on simple random sampling with replacement (SRSWR), was used. The degree of damage to fir (Abies alba Mill.) and beech (Fagus sylvatica L.) was analysed in the Święty Krzyż forest section in the Świętokrzyski National Park. The maximum total estimation errors
for the proportion of trees with a degree zero of damage, and with second and third degrees of damage together (for α = 0.05) were at most 30.8% for fir and 24.3% for beech trees. For standard, small-area evaluations, these are satisfactory
values. In the Święty Krzyż forest section, the number of P3 sub-blocks with 0.00–5.00% of undamaged trees and with 80.01–100.00% of moderately- or severely-damaged trees was significantly
greater for fir than for beech. These results indicate that the fir population was unhealthier than the beech group in the
study area. P3 sub-blocks of the SINUS system, in which the proportion of the healthiest trees was highest, were situated at the forest
margin, bordering on meadows and arable fields (in the case of fir) and forming dense patches consisting of several sub-blocks,
or occurring singly in the whole study area (in the case of beech). The results show the significant differentiation of forest
tree health in small areas. 相似文献
507.
国内外生态环境观测研究台站网络发展概况 总被引:2,自引:1,他引:1
生态环境观测研究台站是开展生态环境研究的重要手段。《国家环境保护"十二五"科技发展规划》将国家环境保护野外观测研究站作为"十二五"能力建设重点内容。分析了目前国内外主要生态环境监测网络,如区域尺度的全球环境监测系统(GEMS)、全球陆地观测系统(GTOS)、国际长期生态研究网络(ILTER)、全球通量观测网络(FLUXNET)和国际生物多样性观测网络(GEO·BON),以及国家尺度的美国长期生态研究网络(US-LTER)、英国环境变化监测网络(ECN)和中国生态系统研究网络(CERN)的发展历程、观测研究进展;总结了生态环境监测网站的发展趋势,即重视台站的联网观测研究,注重观测标准化和规范化及数据共享,重视观测手段智能化与自动化,注重综合观测与模型模拟相结合;提出国家环境保护生态监测台站网络是现有国家环境监测网络的拓展和完善,也是今后开展区域生态环境综合监测与评估的重要基础。 相似文献
508.
综述了我国不同介质中挥发性有机物(VOCs)的环境监测方法标准,介绍了样品采集和前处理、分析方法、质量保证与质量控制等技术内容,以及VOCs监测技术的研究进展。分析了国内VOCs监管控制的现状和重点需求,并在此基础上提出了健全VOCs环境标准体系、完善分类监管的优先控制物种清单、尽快实现VOCs监测工作的常态化、推广应用先进的VOCs监测技术等建议。 相似文献
509.
土地利用变化及林业(LUCF)活动是生态固碳最重要手段。研究确定LUCF温室气体排放核算制度和方法,对平衡碳排放、开展全国统一碳市场交易具有重要基础作用。在综述LUCF温室气体核算理论和方法基础上,借鉴IPCC指南和《省级温室气体清单编制指南(试行)》推荐的基本方法,构建了符合地域特色的LUCF温室气体排放核算制度和方法。采用2014年第九次国家森林资源清查数据,以全国低碳试点省陕西省为实证对象,初步核算了陕西省LUCF温室气体的净排放量,并从排放能力、排放结构和空间特征等角度揭示了陕西省LUCF温室气体的排放特征。结果显示:(1)2014年,陕西省LUCF温室气体净吸收量为1 698.42万t CO_2e,其中森林及其他木质生物质碳贮量净吸收1 852.67万t CO2e,森林转化净排放154.25万t CO_2e。(2)乔木林等优势树种,是陕西省LUCF温室气体排放中重要的固碳源(吸收源)。(3)陕南地区是重要固碳贡献区,陕北地区森林固碳能力较差。最后,针对LUCF温室气体排放核算制度和方法不够完善、森林固碳能力差异较大、区域固碳分化严重等问题,提出了健全温室气体核算制度、平衡森林资源空间分布、改善固碳树种结构等加强陕西省LUCF活动应对气候变化统计核算制度和能力建设的基本措施。 相似文献
510.
Kerim E. Dickson David A. Dzombak 《Journal of the American Water Resources Association》2017,53(5):1121-1132
Interbasin transfers (IBTs) are man‐made transfers of water that cross basin boundaries. These transfers are used to distribute water resources according to supply and demand. The objectives of this work were to quantify the number of IBTs that exist in the United States (U.S.) and to examine the distribution of IBTs and potential causes associated with any observed clustering of IBTs. Defining “basin” was important to enable determination of which transfers qualify as “interbasin.” A variety of definitions are employed by states, with no federal definition. The most recent national studies of IBTs were conducted by the U.S. Geological Survey (USGS) in 1985 and 1986 using USGS Hydrologic Unit Code (HUC) definitions of basins. To build a 2016 inventory of IBTs in the U.S., and to identify where they most commonly occur, the USGS National Hydrography Database (NHD) was utilized in conjunction with the Watershed Boundary Dataset (WBD). Transfers across HUC6 basin boundaries were considered interbasin. Geographical information analysis with the NHD and WBD databases revealed that there are a total of 2,161 man‐made waterways crossing HUC6 basin boundaries in the U.S. IBTs are somewhat concentrated: Florida, Texas, and North Carolina account for over 50% of the total identified IBTs. For some states, identified IBTs are locally clustered. Analysis of these clusters suggests a variety of reasons that IBTs have been built, including population, drainage, and agricultural factors. 相似文献