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1. The effects of habitat fragmentation on the distribution pattern of the moor frog Rana arvalis were investigated. Also, the possible isolation effects of the road network were taken into account.
2. Indications were found that habitat fragmentation partly explains the distribution pattern of the moor frog. The statistical models showed a positive effect of pond size (or marsh area) and a negative effect of road density on the probability of occupation of a moorland pond.
3. Because of the strong correlation between habitat quality variables and isolation variables, no unambiguous effects of isolation, described as the amount of suitable terrestrial habitat (moorland) in the surroundings of a moorland pond in a radius of 100–2000 m, could be demonstrated.
4. Spatial differences in road density can play a role in the selection of optimal locations for nature protection areas. The regression model used in this study predicts a reduced occupation probability in 55% of the study area. In the part of the study area adjacent to a motorway, occupation probability is lowered to less than 30%.
5. European studies of habitat fragmentation on amphibian species revealed a mean distance between occupied ponds of <1 km in all studies. This could be a general rule of thumb for persistent amphibian populations. Effects of pond size on the probability of occupation were more variable.
6. When discussing the effects of habitat fragmentation on amphibians and other ground dwelling species, the negative effects of roads are often underestimated.  相似文献   
95.
道路的生态学影响及其生态建设   总被引:35,自引:3,他引:32  
道路的生态学影响及其生态建设章家恩,徐琅(中国科学院南京土壤研究所,210008)EcologicalImpactsofRoadsandItsEcologicalConstruction.¥ZhangJiaen;XuQi(InstituteofSoi...  相似文献   
96.
The growing wildland-urban interface is a frontier of human-wildlife conflict worldwide. Where natural and developed areas meet, there is potential for negative interactions between humans and wild animals, including wildlife-vehicle collisions. Understanding the environmental and anthropogenic factors leading to these collisions can inform transportation and habitat planning, with an objective of reducing animal mortality and human costs. We investigated spatial, temporal, and species-specific patterns of roadkill on Interstate-280 (I-280) in California, USA, and examined the effects of land cover, fencing, lighting, and traffic. The highway is situated just south of San Francisco, dividing a large wildlife refuge to the west from dense residential areas to the east, and therefore presents a major barrier to wildlife movement. Areas with a higher percentage of developed land east of I-280 and areas with more open space on the west side of I-280 were associated with an increase in overall roadkill, suggesting that hard boundaries at the wildland-urban interface may be zones of high risk for dispersing animals. This pattern was especially strong for raccoons (Procyon lotor) and black-tailed deer (Odocoileus hemionus). The presence of lighting correlated with increased roadkill with the exception of coyote (Canis latrans). Contrary to our expectations, we found weak evidence that fencing increases roadkill, perhaps because animals become trapped on roadways or because fencing is not sufficient to block access to the road by wildlife. Finally, we found strong evidence for roadkill seasonality, correlated with differences in movement and dispersal across life-history stages. We highlight the value of citizen-science datasets for monitoring human-wildlife conflict and suggest potential mitigation measures to reduce the negative effects of wildlife-vehicle collisions for people and wildlife. © 2019 The Wildlife Society.  相似文献   
97.
任飞虹  白骅  邱兆文  田顺 《生态学报》2022,42(13):5177-5186
减少道路环境的颗粒物污染对通勤者的健康至关重要。道路绿地在交通排放和邻近区域之间形成屏障,但这种植被屏障是否可以有效消减局部颗粒物污染仍然需要深入研究和探讨。结合现有研究成果,阐述了植被对颗粒物污染的影响途径;分析了街道峡谷和开放道路两种典型城市道路环境中,植被组成及群落结构设计的关键特征对颗粒物分布和扩散的影响;总结了有利于消减颗粒物浓度的植被单株性状和叶片微形态;探讨了影响颗粒物浓度的其他因子的耦合作用;针对不同道路环境提出了有效的植被屏障设计建议,并指出了植被群落设计和叶片微形态方面的研究趋势,以期优化道路植被规划,改善路域空气质量。  相似文献   
98.
全球交通基础设施网络的不断扩张导致的栖息地丧失和破碎化已成为生物多样性下降的主要影响因素之一。国外开展了大量的道路对野生动物生存影响的研究, 相对而言, 我国在该领域的研究刚刚起步。本文通过总结截止于2021年国内的144篇案例研究文献以及新浪微博中210条道路交通伤害信息, 将我国道路对野生动物的影响分为栖息地丧失、栖息地破碎化、回避或聚集路边、阻碍或促进迁移、种群隔离、野生动物通道和道路交通伤害等方面, 从研究方法、研究地点、研究物种和研究结果等不同角度进行梳理和总结。近年来, 我国的相关研究呈现不断增长的趋势, 研究地点主要集中在可可西里、长白山和秦岭地区; 研究物种主要为青藏高原有蹄类、大熊猫(Ailuropoda melanoleuca)和亚洲象(Elephas maximus)。未来重点发展方向应包括: (1)道路野生动物基础数据采集平台建设; (2)我国不同动物地理分区的道路野生动物相关研究; (3)深入开展学科交叉与部门合作以及国际交流合作。公众在社交媒体发布的相关信息表明近年来公众对道路交通伤害问题越来越关注, 未来开展基于公民科学收集道路交通伤害数据具有迫切性和可行性。  相似文献   
99.
Protected areas are recognized as an essential tool to safeguard habitat integrity and biodiversity in the Anthropocene. Substantial efforts have been made to clarify the conditions under which they deliver conservation outcomes effectively. Location, spatial design, management strategy and threats, have commonly been identified as key factors. The impacts of these factors have, however, often been evaluated independently, and there is limited information on how their combined and interactive effects can improve or hinder protected area effectiveness. Here we develop a framework for understanding the combined effects of these factors. This has important implications for how protected areas are established and maintained.  相似文献   
100.
Roads and associated stream crossings can modify and degrade natural hydrology of a system and alter organism movement. Culvert replacement and stream crossing improvements are extremely common and often done with the intent to improve biotic integrity of a system. We evaluated 3 sites where poor road‐stream crossings were improved by replacing improper culverts with full‐span natural bottom structures. We used a before‐after‐control‐impact paired series (BACIPS) design to determine if there was evidence of associated improvement in biotic integrity of the stream communities. Biotic integrity indices developed for coldwater fish and macroinvertebrates in the Northern Lakes and Forests Ecoregion were used to estimate responses of the biotic communities adjacent to culvert replacements. With poor to fair fish and macroinvertebrate communities prior to culvert replacement, we predicted communities would show improvement into the good range of the indices. With 2–4 years of pre‐data and 3–5 years of postdata, we were not able to detect improvements in overall biotic integrity utilizing fish or macroinvertebrate index scores. Road crossing improvements may synergistically restore stream ecosystems, restore natural sediment dynamics, and improve passage; however, in these cases local biotic integrity scores were not significantly improved. Culvert replacements are often developed based on the potential, or the perception, that they will restore ecological integrity and biological communities or fisheries; however, as restoration practitioners, researchers, and managers, assessing these claims and learning from prior restoration attempts is necessary.  相似文献   
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