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541.
542.
Abstract: Rapidly changing landscapes have spurred the need for quantitative methods for conservation assessment and planning that encompass large spatial extents. We devised and tested a multispecies framework for conservation planning to complement single‐species assessments and ecosystem‐level approaches. Our framework consisted of 4 elements: sampling to effectively estimate population parameters, measuring how human activity affects landscapes at multiple scales, analyzing the relation between landscape characteristics and individual species occurrences, and evaluating and comparing the responses of multiple species to landscape modification. We applied the approach to a community of terrestrial birds across 25,000 km2 with a range of intensities of human development. Human modification of land cover, road density, and other elements of the landscape, measured at multiple spatial extents, had large effects on occupancy of the 67 species studied. Forest composition within 1 km of points had a strong effect on occupancy of many species and a range of negative, intermediate, and positive associations. Road density within 1 km of points, percent evergreen forest within 300 m, and distance from patch edge were also strongly associated with occupancy for many species. We used the occupancy results to group species into 11 guilds that shared patterns of association with landscape characteristics. Our multispecies approach to conservation planning allowed us to quantify the trade‐offs of different scenarios of land‐cover change in terms of species occupancy. 相似文献
543.
陈盛彬 《湖南环境生物职业技术学院学报》2001,7(1):59-62
庙前自然风景区是常宁市天堂山旅游风景区的四大景区之一,它以自然地貌的溶洞、溶岩、峰谷、石林为景观特色,本文就充分利用这些奇特的自然景观资源进行了详细规划,并提出了切实可行的建议。 相似文献
544.
中国的自然保护地具有生态和文化双重价值,文化景观作为自然与文化的交界面,如何识别其价值对中国自然保护地的管理至关重要。以泰山为例,通过古籍文献和实地勘察等方法,从历时性角度对泰山的文化景观价值演变进行剖析。研究发现,泰山文化景观价值经历了山岳崇拜的自然价值、君权神授的政治价值、佛道信仰的宗教价值、祭祀游居的民俗价值及保护利用的综合价值五个阶段。结论认为:自然保护地文化景观价值的演变具有一定的规律性:名山自然保护地的文化景观价值演变是从自然到文化再到综合、从御到民、从单一到多元、从分离到融合的过程;自然保护地文化景观价值的构成要素包括思想基础、环境条件、行为方式及空间结果四部分,具有鲜明的完整性、系统性和动态性特征。文章还对自然保护地文化景观价值的识别策略进行了讨论,为相应类型的国家公园和其他类型自然保护地建设提供参考。 相似文献
545.
论可持续发展的物质体系 总被引:6,自引:0,他引:6
可持续发展的物质体系包括资源、环境和生态。可持续发展的终极基础是资源物质变换,可持续发展的生存依托是环境,可持续发展的动态载体是生态平衡网络。本文通过分析资源、环境和生态之间的关系与相互作用,提出了可持续发展的基础是物质体系的观点。 相似文献
546.
Sean R. Brennan Diego P. Fernandez Jennifer M. Burns Stephanie Aswad Daniel E. Schindler Thure E. Cerling 《Conservation biology》2019,33(6):1415-1425
Human activities threaten the biodiversity of aquatic mammals across the globe. Conservation of these species hinges on the ability to delineate movements and foraging behaviors of animals, but gaining such insights is hampered by difficulties in tracing individuals over their lives. We determined isotope ratios in teeth (87Sr/86Sr, 13C/12C, and 18O/16O) to examine lifelong movement and resource-use patterns of a unique freshwater population of a wide-ranging pinniped species (harbor seal [Phoca vitulina]) that resides in Iliamna Lake, Alaska (U.S.A.). This population's potentially unique migratory behavior and use of different trophic resources are unknown. The isotope ratios we measured in teeth showed that seals were born in the lake, remained lifelong residents, and relied principally on resources produced from in the lake, even when seasonally abundant and nutrient-dense spawning anadromous fish (i.e., sockeye salmon [Oncorhynchus nerka]) were available in the lake. Our results illustrate how serial isotope records in teeth, particularly 87Sr/86Sr ratios, can be used to quantify how coastal mammal populations exploit both freshwater and marine ecosystems. Understanding lifelong patterns of habitat and resource use is essential information when designing effective conservation plans for threatened coastal mammals. We present the Iliamna Lake harbor seals as a unique case study into how isotope records within teeth can help reveal the cryptic ecology of such a population residing in an intact ecosystem. The results also provide critical baseline information for the Kvichak River system, which is facing an uncertain future due to proposed large-scale industrial development and a rapidly changing climate. 相似文献
547.
David Amuzu 《Local Environment》2018,23(6):603-618
This paper provides additional empirical knowledge of injustice embedded in the urban governance of informal-sector electronic waste (e-waste) recycling in Ghana. It uses Urban Political Ecology and Environmental Justice perspectives to explain how divergent interest and power among diverse actors in the e-waste sector engender social and environmental (in)justice in Accra. Using the case study approach, this paper reveals that the persistent struggles over interest and power which characterise the governance and management of informal e-waste recycling generate inequity, false accusations, misrecognition, disrespect, devaluation, neglect, exclusion, and abuse of freedom and rights. Inclusive of the finding is the development of local resistance and social movement in defence of interests and against state aggression, oppression, domination and neglect. The study concludes to suggest that the governance of urban socio-economic and ecological space of Accra should involve coordination, participation, holistic inclusion of diverse interest, so as to minimise trade-offs and reap synergies. 相似文献
548.
Kristina Douglass Jonathan Walz Eréndira Quintana Morales Richard Marcus Garth Myers Jacques Pollini 《Conservation biology》2019,33(2):260-274
The human communities and ecosystems of island and coastal southeast Africa face significant and linked ecological threats. Socioecological conditions of concern to communities, governments, nongovernmental organizations, and researchers include declining agricultural productivity, deforestation, introductions of non-native flora and fauna, coastal erosion and sedimentation, damage to marine environments, illegal fishing, overfishing, waste pollution, salinization of freshwater supplies, and rising energy demands, among others. Human–environment challenges are connected to longer, often ignored, histories of social and ecological dynamics in the region. We argue that these challenges are more effectively understood and addressed within a longer-term historical ecology framework. We reviewed cases from Madagascar, coastal Kenya, and the Zanzibar Archipelago of fisheries, deforestation, and management of human waste to encourage increased engagement among historical ecologists, conservation scientists, and policy makers. These case studies demonstrate that by widening the types and time depths of data sets we used to investigate and address current socioecological challenges, our interpretations of their causes and strategies for their mitigation varied significantly. 相似文献
549.
Denise M. Thompson Day B. Ligon Jason C. Patton Monica Papeş 《Conservation biology》2017,31(2):427-436
Survival and reproduction are the two primary life‐history traits essential for species’ persistence; however, the environmental conditions that support each of these traits may not be the same. Despite this, reproductive requirements are seldom considered when estimating species’ potential distributions. We sought to examine potentially limiting environmental factors influencing the distribution of an oviparous reptile of conservation concern with respect to the species’ survival and reproduction and to assess the implications of the species’ predicted climatic constraints on current conservation practices. We used ecological niche modeling to predict the probability of environmental suitability for the alligator snapping turtle (Macrochelys temminckii). We built an annual climate model to examine survival and a nesting climate model to examine reproduction. We combined incubation temperature requirements, products of modeled soil temperature data, and our estimated distributions to determine whether embryonic development constrained the northern distribution of the species. Low annual precipitation constrained the western distribution of alligator snapping turtles, whereas the northern distribution was constrained by thermal requirements during embryonic development. Only a portion of the geographic range predicted to have a high probability of suitability for alligator snapping turtle survival was estimated to be capable of supporting successful embryonic development. Historic occurrence records suggest adult alligator snapping turtles can survive in regions with colder climes than those associated with consistent and successful production of offspring. Estimated egg‐incubation requirements indicated that current reintroductions at the northern edge of the species’ range are within reproductively viable environmental conditions. Our results highlight the importance of considering survival and reproduction when estimating species’ ecological niches, implicating conservation plans, and benefits of incorporating physiological data when evaluating species’ distributions. 相似文献
550.
四川不同海拔稻田生态条件与杂交水稻生长发育及其应用研究 总被引:5,自引:0,他引:5
对φ(N)32°14′~32°56′,λ(E)104°36′~104°51′范围内400~1400m稻田小气候进行了观测,发现海拔(halt)不同,稻田生态环境相差很大:halt每升高100m,平均气温(θar)递减0.72℃,年降雨量递增63.0mm(400~600m)~106.8mm(800~1400m),相对湿度递增1%,日照时数呈抛物线上升变化.halt400m日均温稳定通过12.0℃的初期为3月中旬,halt每升高100m,该时间延迟5~7d.不同halt>12℃的有效积温分别为3621.2℃(400m)、3245.0℃(600m)、3149.9℃(800m)、2804.8℃(1000m)、2082.1℃(1200m)、1950.1℃(1400m).在相对较高的halt,存在明显的逆温和南北坡效应,相应存在杂交水稻局部高产区.本研究结果为四川不同海拔区杂交水稻品种合理布局和应用高产优质栽培技术提供了基础理论依据 相似文献