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81.
Scientists increasingly rely on protected areas to assist in biodiversity conservation, yet the efficacy of these areas is rarely systematically assessed, often because of underfunding. Still, adaptive management strategies to maximize conservation success often rely on understanding the temporal and spatial dynamism of populations therein. Examination of environmental DNA (eDNA) is a time and cost‐effective way to monitor species’ distribution, and quantitative polymerase chain reaction (qPCR) provides information on organismal abundance. To date, however, such techniques remain underused for population assessments in protected areas. We determined eDNA concentration of the critically endangered Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) to describe its occurrence, range, and use of the Tian e‐Zhou National Nature Reserve in Hubei, China, across seasons and hydrological depths. Despite the observation that total eDNA concentrations were highest in surface waters in summer, finless porpoise eDNA concentrations were significantly higher in deeper waters than in surface waters in summer. During the breeding season (spring), eDNA signals were site specific and restricted to the core area of the reserve. However, postbreeding eDNA concentrations were widespread across the reserve, encompassing sites previously thought to be unfrequented by the species. Our results suggest spatiotemporal idiosyncrasies in site, depth, and seasonal use of the reserve and a propensity for postbreeding population dispersal. With eDNA and qPCR we were able to assess an entire population's use of a protected area. Illuminating nuances in habitat use via eDNA could be valuable to set pragmatic conservation goals for this, and other, species.  相似文献   
82.
Abstract

On the basis of applying quantitative and qualitative approaches as well as GIS technology, this paper established an index system to make a comprehensive evaluation on socioeconomic development of minority areas in China. The result showed that socio-economic development in minority area presents a series of characteristics that the north is high and the south is low, center-margin pattern is obvious and the areas with middle and lower development indices are distributed centrally and continuously. However, the causes of the socioeconomic characteristics mainly include natural conditions, economic development basic, population cultural quality, regional combination and development conditions of mineral and energy resources, informal institutional factors and distribution of major traffic lines.  相似文献   
83.
Infectious Diseases and Extinction Risk in Wild Mammals   总被引:3,自引:0,他引:3  
Abstract:  Parasite-driven declines in wildlife have become increasingly common and can pose significant risks to natural populations. We used the IUCN Red List of Threatened and Endangered Species and compiled data on hosts threatened by infectious disease and their parasites to better understand the role of infectious disease in contemporary host extinctions. The majority of mammal species considered threatened by parasites were either carnivores or artiodactyls, two clades that include the majority of domesticated animals. Parasites affecting host threat status were predominantly viruses and bacteria that infect a wide range of host species, including domesticated animals. Counter to our predictions, parasites transmitted by close contact were more likely to cause extinction risk than those transmitted by other routes. Mammal species threatened by parasites were not better studied for infectious diseases than other threatened mammals and did not have more parasites or differ in four key traits demonstrated to affect parasite species richness in other comparative studies. Our findings underscore the need for better information concerning the distribution and impacts of infectious diseases in populations of endangered mammals. In addition, our results suggest that evolutionary similarity to domesticated animals may be a key factor associated with parasite-mediated declines; thus, efforts to limit contact between domesticated hosts and wildlife could reduce extinction risk.  相似文献   
84.
杨帆  宗立  沈珏琳  刘乐峰 《自然资源学报》2020,35(10):2311-2324
“双评价”是国土空间规划体系具有前置和基础性作用的制度设定与技术基础。结合实践案例对“试行指南”进行理论思考,结果发现:“双评价”的技术、逻辑路径内含有科学问题和假设;同时,对制度建构具有约束和纠偏作用。“双评价”发挥有效作用需兼顾科学性和政策性,也因此难以两全齐美。技术方法和数据方面存在“加合困境”“分解困境”和“排序困境”。合理有效的“双评价”需要提高两个评价内容的技术合理性,并通过两者耦合进一步提升合理性。也要充分适应决策机制与主体目标,认识科学研究与决策支持研究之间的差异,根据不同层级地方政府事权层级和分工关系优化分析评价方法。结论对“双评价”定位优化与技术逻辑改进有实践指导意义。  相似文献   
85.
目前的企业应急预案与政府应急预案缺乏有效的衔接,重大事故发生时企业周边公众因不能及时疏散而造成严重伤亡,“一对一”预案的目标是在科学分析事故风险的基础上充分发挥属地政府在应急救援中的重要作用。对“一对一”应急预案的编制重点进行了分析研究,提出了编制框架和技术要求,并以某厂液氯液氨库房为例,通过事故后果、个人风险的定量计算,结合厂周边边环境情况规划了事故后的疏散范围、当地街道(地区)办事处的疏散工作片区划分及避难路线。“一对一”预案的编制有助于增强重大危险源企业与属地政府的应急联动,减少事故伤亡。  相似文献   
86.
我国经济持续发展主要体现之一就是大规模的基础工程、道路交通和城市建设。近年来,各种灾害频繁发生,造成了巨大的人身和财产损失,也给"国土规划建设"和"城市防灾规划"工作提出了更迫切更严峻的挑战。我国拥有广大面积的洪泛区[2],洪灾是制约我国社会和经济可持续发展的重要因素;我国又是淡水资源极度缺乏的国家,雨水是淡水,应变灾害为资源。调整区域土地的使用性质和格局,国土规划建设是今后一个时期内科学发展、可持续发展的基础,做好国土规划建设刻不容缓。把国土规划建设结合其它城市灾害提出具体的措施,整体提高我国城市防灾规划水平,以达到节约投入,节省时间,根治水患、长期受益的目的。  相似文献   
87.
近地层臭氧(O_3)会对植物的生长和产量均产生一定的负效应。由于人类活动引起的不断升高的近地层O_3浓度已经威胁到世界粮食安全。O_3主要以干沉降的方式沉降到陆地生态系统,所以需要定量确定陆地生态系统中O_3通量、干沉降速率和不同沉降通道的沉降过程,预测其对植物的潜在影响。介绍了目前O_3干沉降的主要观测方法及其模拟模型,从4个方面(O_3通量和干沉降速率的季节变化、日变化、气象因子等对O_3干沉降的影响、不同O_3沉降通道的沉降过程)重点评述了不同陆地生态系统O_3干沉降观测和模拟的研究进展现状,并对未来的研究工作进行了展望,以期为我国未来开展相关研究工作提供借鉴。  相似文献   
88.
近地层臭氧(O3)会对植物的生长和产量均产生一定的负效应。由于人类活动引起的不断升高的近地层O3浓度已经威胁到世界粮食安全。O3主要以干沉降的方式沉降到陆地生态系统,所以需要定量确定陆地生态系统中O3通量、干沉降速率和不同沉降通道的沉降过程,预测其对植物的潜在影响。介绍了目前O3干沉降的主要观测方法及其模拟模型,从4个方面(O3通量和干沉降速率的季节变化、日变化、气象因子等对O3干沉降的影响、不同O3沉降通道的沉降过程)重点评述了不同陆地生态系统O3干沉降观测和模拟的研究进展现状,并对未来的研究工作进行了展望,以期为我国未来开展相关研究工作提供借鉴。  相似文献   
89.
广西大明山自然保护区哺乳动物资源调查研究   总被引:1,自引:0,他引:1  
2000年9月11日至26日,在广西省大明山自然保护区采集哺乳动物81只(种),共计19种,隶属5目,11科.结合以往的调查资料,已知大明山自然保护区有哺乳动物动物60种,隶属8目,22科,47属.保护区内的哺乳动物多样性系数(H”)为2.5555,均匀度指数(J)为O.8679,动物的密度为231.23只/km2.  相似文献   
90.
To augment mammal conservation in the Eastern Himalayan region, we assessed the resident 255 terrestrial mammal species and identified the 50 most threatened species based on conservation status, endemism, range size, and evolutionary distinctiveness. By using the spatial analysis package letsR and the complementarity core‐area method in the conservation planning software Zonation, we assessed the current efficacy of their protection and identified priority conservation areas by comparing protected areas (PAs), land cover, and global ecoregion 2017 maps at a 100 × 100 m spatial scale. The 50 species that were most threatened, geographically restricted, and evolutionarily distinct faced a greater extinction risk than globally nonthreatened and wide‐ranging species and species with several close relatives. Small, medium‐sized, and data‐deficient species faced extinction from inadequate protection in PAs relative to wide‐ranging charismatic species. There was a mismatch between current PA distribution and priority areas for conservation of the 50 most endangered species. To protect these species, the skewed regional PA distribution would require expansion. Where possible, new PAs and transboundary reserves in the 35 priority areas we identified should be established. There are adequate remaining natural areas in which to expand current Eastern Himalayan PAs. Consolidation and expansion of PAs in the EH requires strengthening national and regional transboundary collaboration, formulating comprehensive regional land‐use plans, diversifying conservation funding, and enhancing information sharing through a consolidated regional database.  相似文献   
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