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781.
In pursuit of socioeconomic development, many countries are expanding oil and mineral extraction into tropical forests. These activities seed access to remote, biologically rich areas, thereby endangering global biodiversity. We examined how protection of biodiversity and economic revenues can be balanced in biologically valuable regions. Using spatial data on oil profits and predicted species and ecosystem extents, we optimized the protection of 741 terrestrial species and 20 ecosystems of the Ecuadorian Amazon across a range of opportunity costs (i.e., sacrifices of extractive profit). We also applied spatial statistics to remotely sensed, historic deforestation data to focus the optimization on areas most threatened by imminent forest loss. Giving up 5% of a year's oil profits (US$221 million) allowed for a protected area network that retained an average of 65% of the extent of each species and ecosystem. This performance far exceeded that of the network produced by simple optimization for land area (which required a sacrifice of approximately 40% of annual oil profits [US$1.7 billion]) and used only marginally less land to achieve equivalent levels of ecological protection. We identified what we call emergency conservation targets: regions that are essential components of a cost-effective conservation reserve network but at imminent risk of destruction, thus requiring urgent and effective protection. Governments can use our methods when evaluating extractive-led development options to responsibly manage the associated ecological and economic trade-offs and protect natural capital.  相似文献   
782.
生物多样性保护领域中的国际条约设有知识产权条款,知识产权条款发挥鼓励创新的基本功能。现有生物多样性利用中存在的知识产权问题集中在获取和惠益分享、遗传资源公开和利用知识产权产生的利益三方面。随着数字开源运动和数据库的大量兴起,协调型知识产权规则因缺乏强制力,使知识产权条款发挥的效力大打折扣。加之知识产权的专有属性和产业化,使得知识产权和多样性保护之间的冲突加剧。中国积极参与生物多样性保护全球治理,由被动参与者转换为积极推动者,确认和实施知识产权规则,关注数字序列信息的发展并加强农民权利的表达。  相似文献   
783.
In response to the pressing global challenges of climate change, initiatives under the auspices of ‘reducing emissions from deforestation and forest degradation’ (REDD) have been implemented in over 30 developing and least-developed countries since 2005. The initiatives cover nearly every significant and vulnerable forest ecosystem worldwide. In this study we review six representative initiatives, two each from Africa, Asia and Latin America. Strength, weakness, opportunity and threat analysis is done to evaluate each initiative's policy framework, design, implementation and results thus far. The main policy and project implementation factors that appear to lead to effective and successful REDD project outcomes include having clearly formulated project design; governance, land tenure rights and capacity; equity and transparency; indigenous peoples' rights and knowledge; local–international coordination; and enhancing local and institutional capacities. Based on these findings, we provide recommendations for future REDD policy action and project implementation to make it work for the poor and achieve its intended goals.  相似文献   
784.
2020年全球生物多样性目标解读及其评估指标探讨   总被引:8,自引:0,他引:8  
2010年以来,全球开展了讨论和咨询,确定世界生物多样性保护的路线图。2010年10月在日本召开的《生物多样性公约》缔约方大会第十次会议通过了《生物多样性战略计划》(2011—2020年)。该战略计划确立了2020年全球生物多样性目标(简称2020年目标),设计了世界生物多样性保护的路线图和时间表,为制定国家目标提供了灵活的框架。该文剖析了《生物多样性公约》各缔约方对2020年目标的谈判立场,解读了2020年目标的内涵,论述了2020年目标评估指标研究的最新进展,在进一步加强生物多样性评价指标研究、建设生物多样性监测标准和网络、开展生物多样性长期监测方面提出了建议。  相似文献   
785.
786.
Abstract:  Our understanding of fire and grazing is largely based on small-scale experimental studies in which treatments are uniformly applied to experimental units that are considered homogenous. Any discussion of an interaction between fire and grazing is usually based on a statistical approach that ignores the spatial and temporal interactions on complex landscapes. We propose a new focus on the ecological interaction of fire and grazing in which each disturbance is spatially and temporally dependent on the other and results in a landscape where disturbance is best described as a shifting mosaic (a landscape with patches that vary with time since disturbance) that is critical to ecological structure and function of many ecosystems. We call this spatiotemporal interaction pyric herbivory (literal interpretation means grazing driven by fire). Pyric herbivory is the spatial and temporal interaction of fire and grazing, where positive and negative feedbacks promote a shifting pattern of disturbance across the landscape. We present data we collected from the Tallgrass Prairie Preserve in the southern Great Plains of North America that demonstrates that the interaction between free-roaming bison ( Bison bison ) and random fires promotes heterogeneity and provides the foundation for biological diversity and ecosystem function of North American and African grasslands. This study is different from other studies of fire and grazing because the fires we examined were random and grazing animals were free to roam and select from burned and unburned patches. For ecosystems across the globe with a long history of fire and grazing, pyric herbivory with any grazing herbivore is likely more effective at restoring evolutionary disturbance patterns than a focus on restoring any large vertebrate while ignoring the interaction with fire and other disturbances .  相似文献   
787.
Abstract:  Managed landscapes in which non-native ornamental plants are favored over native vegetation now dominate the United States, particularly east of the Mississippi River. We measured how landscaping with native plants affects the avian and lepidopteran communities on 6 pairs of suburban properties in southeastern Pennsylvania. One property in each pair was landscaped entirely with native plants and the other exhibited a more conventional suburban mixture of plants—a native canopy with non-native groundcover and shrubs. Vegetation sampling confirmed that total plant cover and plant diversity did not differ between treatments, but non-native plant cover was greater on the conventional sites and native plant cover was greater on the native sites. Several avian (abundance, species richness, biomass, and breeding-bird abundance) and larval lepidopteran (abundance and species richness) community parameters were measured from June 2006 to August 2006. Native properties supported significantly more caterpillars and caterpillar species and significantly greater bird abundance, diversity, species richness, biomass, and breeding pairs of native species. Of particular importance is that bird species of regional conservation concern were 8 times more abundant and significantly more diverse on native properties. In our study area, native landscaping positively influenced the avian and lepidopteran carrying capacity of suburbia and provided a mechanism for reducing biodiversity losses in human-dominated landscapes.  相似文献   
788.
Some conservationists believe that free-ranging cats pose an enormous risk to biodiversity and public health and therefore should be eliminated from the landscape by any means necessary. They further claim that those who question the science or ethics behind their arguments are science deniers (merchants of doubt) seeking to mislead the public. As much as we share a commitment to conservation of biodiversity and wild nature, we believe these ideas are wrong and fuel an unwarranted moral panic over cats. Those who question the ecological or epidemiological status of cats are not science deniers, and it is a false analogy to compare them with corporate and right-wing special interests that perpetrate disinformation campaigns over issues, such as smoking and climate change. There are good conservation and public-health reasons and evidence to be skeptical that free-ranging cats constitute a disaster for biodiversity and human health in all circumstances. Further, there are significant and largely unaddressed ethical and policy issues (e.g., the ethics and efficacy of lethal management) relative to how people ought to value and coexist with cats and native wildlife. Society is better served by a collaborative approach to produce better scientific and ethical knowledge about free-ranging cats.  相似文献   
789.
Abstract:  Moving from single-species- to ecosystem-based management requires an understanding of how community-level attributes such as diversity change with area. We used survey data from bottom trawls to examine spatial patterns of species richness in U.S. Pacific coastal fishes. Specifically, we generated and compared species–area relationships (SARs) for species classified into several groups on the basis of maximum body size, trophic level, diet, maximum depth, geographic affinity, and taxonomic order. Because SARs among groups were not parallel and z values varied significantly for several groups, groups of species were under- or overrepresented (depending on the size of the area) relative to their proportions in the entire community (i.e., entire U.S. Pacific coast). In this way, differences in SARs help demonstrate trade-offs between species representation and coastal area and suggest strategies (such as targeting the protection of habitats and locations where a particular species or groups of species are maximized) that may minimize the size of marine protected areas (MPAs) but protect diversity at the level of the community and functional group.  相似文献   
790.
长期施肥对旱地土壤杂草种子库生物多样性影响的研究   总被引:3,自引:0,他引:3  
为探讨长期施肥对旱地土壤杂草种子库生物多样性的影响,我们在安徽蒙城地区的一个长期肥料试验定位监测点开展了相关研究。采用镜检法对旱地土壤表层(0~15 cm)中土壤杂草种子的种类进行鉴定并计数,记录杂草种子22种,隶属15科。不同施肥处理区杂草种子丰富度以NP1/2K区最高(14.7种),PK区最低(10.7种);其中陌上菜(Lindernia procumbens)、栗米草(Mollugo pentaphylla)、醴肠(Eclipta prostrata)、泽星宿菜(Lysimachia candida lindl)四种杂草的种子密度较大,分别在不同的处理区占据优势;从整个试验区来看,烟台飘拂草(Fimbristylis stauntoni)在所有处理中的密度都比较大,处于优势地位。长期不同施肥方式下,农田土壤杂草种子库的物种多样性有显著差异:PK区Shanon-Wiener指数大于其他处理区,但是Simpson优势度指数最低;NPK区Simpson优势度指数最高;PK、CK区Pielou均匀度指数大于其他处理区。田间杂草种子库的群落结构及其物种组成也发生了一定的变化,Whittaker指数表明,与不施肥处理相比较,半量的P和缺N的影响最显著,缺P次之,缺K和平衡施肥则没有显著影响。Sorenson群落相似性指数和Bray Curtis指数聚类分析结果表明,与不施肥相比较,长期施用N、P、K肥能显著改变旱地土壤杂草种子库的组成。本研究表明长期平衡施肥处理更有利于维持和保护旱地土壤杂草种子库的生物多样性。  相似文献   
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