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661.
Ladybirds (Coleoptera: Coccinellidae) provide services that are critical to food production, and they fulfill an ecological role as a food source for predators. The richness, abundance, and distribution of ladybirds, however, are compromised by many anthropogenic threats. Meanwhile, a lack of knowledge of the conservation status of most species and the factors driving their population dynamics hinders the development and implementation of conservation strategies for ladybirds. We conducted a review of the literature on the ecology, diversity, and conservation of ladybirds to identify their key ecological threats. Ladybird populations are most affected by climate factors, landscape composition, and biological invasions. We suggest mitigating actions for ladybird conservation and recovery. Short-term actions include citizen science programs and education, protective measures for habitat recovery and threatened species, prevention of the introduction of non-native species, and the maintenance and restoration of natural areas and landscape heterogeneity. Mid-term actions involve the analysis of data from monitoring programs and insect collections to disentangle the effect of different threats to ladybird populations, understand habitat use by taxa on which there is limited knowledge, and quantify temporal trends of abundance, diversity, and biomass along a management-intensity gradient. Long-term actions include the development of a worldwide monitoring program based on standardized sampling to fill data gaps, increase explanatory power, streamline analyses, and facilitate global collaborations.  相似文献   
662.
Europe has a long history of human pressure on freshwater ecosystems. As pressure continues to grow and new threats emerge, there is an urgent need for conservation of freshwater biodiversity and its ecosystem services. However, whilst some taxonomic groups, mainly vertebrates, have received a disproportionate amount of attention and funds, other groups remain largely off the public and scientific radar. Freshwater mussels (Bivalvia, Unionida) are an alarming example of this conservation bias and here we point out six conceptual areas that need immediate and long-term attention: knowledge, threats, socioeconomics, conservation, governance and education. The proposed roadmap aims to advance research, policy and education by identifying the most pressing priorities for the short- and long-term conservation of freshwater mussels across Europe.  相似文献   
663.
Red lists are a crucial tool for the management of threatened species and ecosystems. Among the information red lists provide, the threats affecting the listed species or ecosystem, such as pollution or hunting, are of special relevance. This information can be used to quantify the relative contribution of different threat factors to biodiversity loss by disaggregating the cumulative extinction risk across species into components that can be attributed to certain threats. We devised and compared 3 metrics that accomplish this and may be used as indicators. The first metric calculates the portion of the temporal change in red list index (RLI) values that is caused by each threat. The second metric attributes the deviation of an RLI value from its reference value to different threats. The third metric uses extinction probabilities that are inferred from red list categories to estimate the contribution of a threat to the expected loss of species or ecosystems within 50 years. We used data from Norwegian Red Lists to test and evaluate these metrics. The first metric captured only a minor portion of the biodiversity loss caused by threats because it ignores species whose red list category does not change. Management authorities will often be interested in the contribution of a given threat to the total deviation from the optimal state. This was measured by the remaining metrics. The second metric was best suited for comparisons across countries or taxonomic groups. The third metric conveyed the same information but uses numbers of species or ecosystem as its unit, which is likely more intuitive to lay people and may be preferred when communicating with stakeholders or the general public.  相似文献   
664.
Experts can provide valuable information to fill knowledge gaps in published research on management effectiveness, particularly for threatened ecosystems, for which there is often limited evidence and the need for prompt intervention to ensure their persistence. One such ecosystem, alpine peatland, is threatened by climate change and other pressures, provides vital ecosystem services, and supports unique biodiversity. In a workshop, we gathered and synthesized into an accessible format information from experts on interventions used, threat context, and intervention effectiveness for Australian alpine peatland and used this knowledge to evaluate local relevance of the global literature for this threatened ecosystem. Experts identified 15 interventions used to conserve Australian peatlands, most of which enhanced or restored peatland condition and effectively addressed diverse threats. Experts’ perspectives and global studies were strongly aligned, suggesting that research on peatland management may be broadly relevant across contexts, despite the distinct characteristics of Australian systems. Our workshop-based expert elicitation approach provided insights into current management practices unavailable in the literature.  相似文献   
665.
The European Environmental Liability Directive aims to ensure that damaged habitats are restored where possible, but allows for complementary remediation with replacement habitat where restoration is not possible within a reasonable time. It also allows for compensatory remediation of the resource based on an assessment of environmental values in cases where there are interim social losses. This paper concurs with the argument that physical remediation without consideration of social values can fail to be equivalent to the resource that has been lost. Using, as a case study, a river in Ireland, it demonstrates that estimating social value can be challenging in practice, noting also differences between the value of environmental gains and losses. The paper argues that estimates of final ecosystem service values, including wastewater treatment costs, can provide a measure of social value and makes a case for the systematic collection of these data to inform decision-making.  相似文献   
666.
利用2013年遥感影像和地形图制作地势图,将万子湖湿地洲滩分为27 m以下、27~28、28~29、29~30、30 m以上共5级地势阶梯。利用1983~2013年万子湖逐日平均水位数据分析不同地势阶梯洲滩在春汛期、洪水期、退水期、枯水期等4个时段的淹水特征,结合生物特性和人为干扰分析,确定万子湖湿地生态系统管理的边界范围和策略。研究表明:4个时段中的生态系统管理边界分别为29、31、29、28 m地势阶梯分界线,3个重点时段和管理区域为:春汛期,管理目标是产卵亲鱼保护,28 m以下洲滩是重点管理区域;退水期,管理目标是保障鱼类洄游,28 m以下洲滩和湖槽洄游通道是重点管理区域;枯水期,管理目标是洲滩上鱼类产卵场、幼鱼索饵场和越冬候鸟栖息地的恢复与保护,28 m以下洲滩是重点管理区域。而生态系统管理重点则是去除过度人为干扰(包括洲滩过度开发、过度捕捞),恢复湿地生态系统整体性功能,应坚决停止重点区域内滩涂水面的养殖承包、引淤抬洲、洲滩植树等系列干扰性活动。  相似文献   
667.
城市化发展引起的土地利用方式和生态系统质量的变化逐渐引起人们的重视,人类的社会经济活动已经对生态系统的结构和功能造成了很大影响。以上海市为研究对象,从生态系统结构、功能和胁迫3个方面构建生态系统质量评价模型,研究了2000年、2005年、2010年3个时期生态系统质量变化、空间差异及其影响因素。结果表明,崇明县和中心城区生态结构指数最高;崇明县功能指数最高,中心城区最低;崇明县受城市化胁迫最小,中心城区胁迫最大。崇明县是上海市生态系统质量最好的区域,3个时期生态系统质量指数均处于1级水平,中心城区生态系统质量最差。提供了一种生态系统质量评价的方法,研究结果揭示了上海市2000-2010年生态系统质量演变趋势,可以为上海市生态系统管理提供参考依据。  相似文献   
668.
我国境内石油行业总体呈现原油开采量上升的态势,为之付出的经济和生态成本也越来越大。开展我国境内石油资源资产负债表的编制工作对于摸清我国石油资源的家底、评估我国石油资源开采的经济—资源—环境综合成本、探讨我国石油开采战略的合理性具有重要的意义。本文首先探讨了石油资源资产负债表的编制方法和框架,构建了集"生态系统服务"、"环境污染"和"资源消耗"三位于一体的"生态负债"账户。其次,收集并整理了重要的污染物处理成本和生态系统服务的价值评估成果,构建了价值化因子数据表。最后,基于2012年数据尝试编制了目前我国的第一份石油资源资产负债表。结果显示,(1)2012年末,我国石油资源的资产总额为1.47×109万元,负债总额为9.03×107万元,所有者权益为1.38×109万元;(2)石油资源资产总额占到当年政府资产总额的14.43%,占政府资源性资产比重达31.12%;(3)石油行业的资产负债率为6.15%,负债权益比达到了6.56%;(4)"生态系统服务"构成了负债的最大比重,达到了98.16%。总的来说,我国石油开采行业整体处于"高资产、高负债、强生态压力和弱可持续性"的状态。从这份资产负债表我们可以看出,我国境内石油开采的生态成本不容忽视。随着资源的不断开发,石油开采的边际生态成本只会越来越大,因此,能指向经济和生态两方面的综合成本应该取代账面成本成为政府进行石油资源开发的决策依据之一。此外,要落实石油资源资产负债表对于生态保护的实际指导意义,我们建议应该将石油资源开采的资产负债率、负债权益比等指标纳入官员的绩效考核体系。  相似文献   
669.
In the wake of Hurricane Sandy and other recent extreme events, urban coastal communities in the northeast region of the United States are beginning or stepping up efforts to integrate climate adaptation and resilience into long-term coastal planning. Natural and nature-based shoreline strategies have emerged as essential components of coastal resilience and are frequently cited by practitioners, scientists, and the public for the wide range of ecosystem services they can provide. However, there is limited quantitative information associating particular urban shoreline design strategies with specific levels of ecosystem service provision, and research on this issue is not always aligned with decision context and decision-maker needs. Engagement between the research community, local government officials and sustainability practitioners, and the non-profit and private sectors can help bridge these gaps. A workshop to bring together these groups discussed research gaps and challenges in integrating ecosystem services into urban sustainability planning in the urban northeast corridor. Many themes surfaced repeatedly throughout workshop deliberations, including the challenges associated with ecosystem service valuation, the transferability of research and case studies within and outside the region, and the opportunity for urban coastal areas to be a focal point for education and outreach efforts related to ecosystem services.  相似文献   
670.
化学污染物是影响珊瑚礁生态系统健康的重要因素之一。随着我国社会经济的发展,沿海农业活动、城市工业化以及旅游业的发展导致珊瑚礁生长区的化学污染物浓度越来越高。珊瑚礁生态系统长期在化学污染物的联合胁迫下,生态风险指数日益增加,受到国内外研究者的极大关注。本文综述了国内外该领域的重要研究进展,并从个体、细胞和分子水平重点介绍了化学污染物对珊瑚的影响,主要包括:(1)珊瑚礁对重金属和多环芳烃有明显的富集作用,可以作为该海域化学污染物污染水平的外在反映;(2)化学污染物对珊瑚幼体的影响程度比成体大;(3)抗氧化酶和特定的功能基因可被用作生物标记物来监测珊瑚礁生态系统的健康状况。最后,对我国未来珊瑚礁生态系统的研究方向进行展望,建议在典型珊瑚礁海域进行长期的生态学监测,结合室内胁迫实验,筛选出敏感的生物标志物(biomarker),为今后珊瑚礁生态系统的保护提供基础信息,并对其可能存在的环境风险进行评价。  相似文献   
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