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81.
Nicole Shumway Megan I. Saunders Sam Nicol Richard A. Fuller Noam Ben-Moshe Takuya Iwamura Sun W. Kim Nicholas J. Murray James E. M. Watson Martine Maron 《Conservation biology》2023,37(2):e14031
Biodiversity offsets aim to counterbalance the residual impacts of development on species and ecosystems. Guidance documents explicitly recommend that biodiversity offset actions be located close to the location of impact because of higher potential for similar ecological conditions, but allowing greater spatial flexibility has been proposed. We examined the circumstances under which offsets distant from the impact location could be more likely to achieve no net loss or provide better ecological outcomes than offsets close to the impact area. We applied a graphical model for migratory shorebirds in the East Asian–Australasian Flyway as a case study to explore the problems that arise when incorporating spatial flexibility into offset planning. Spatially flexible offsets may alleviate impacts more effectively than local offsets; however, the risks involved can be substantial. For our case study, there were inadequate data to make robust conclusions about the effectiveness and equivalence of distant habitat-based offsets for migratory shorebirds. Decisions around offset placement should be driven by the potential to achieve equivalent ecological outcomes; however, when considering more distant offsets, there is a need to evaluate the likely increased risks alongside the potential benefits. Although spatially flexible offsets have the potential to provide more cost-effective biodiversity outcomes and more cobenefits, our case study showed the difficulty of demonstrating these benefits in practice and the potential risks that need to be considered to ensure effective offset placement. 相似文献
82.
This paper relies on Gjølberg’s national corporate social responsibility (CSR) index while its purpose is twofold. First, it seeks to extend the methodological instrument for assessing national CSR and, second, it applies the new approach to a much larger pool of countries (n = 86) in an attempt to provide a global CSR outlook. The emergent picture from the study is one of deficient CSR penetration and wide variation among countries where most of the assessed countries are still lagging in the endorsement of international CSR initiatives and schemes. Findings offer fertile ground to theorists and researchers for a deeper investigation of the national specificity of CSR and to further identify institutional determinants that shape the social responsiveness and self-regulation of business entities. The study has also implications for managers and top executives to consider as it infers that the national background can be influential in the development of a CSR agenda and can condition the level of CSR penetration. 相似文献
83.
Agroforestry systems have substantial potential to conserve native biodiversity and provide ecosystem services. In particular, agroforestry systems have the potential to conserve native tree diversity and sequester carbon for climate change mitigation. However, little research has been conducted on the temporal stability of species diversity and aboveground carbon stocks in these systems or the relation between species diversity and aboveground carbon sequestration. We measured changes in shade‐tree diversity and shade‐tree carbon stocks in 14 plots of a 35‐ha coffee cooperative over 9 years and analyzed relations between species diversity and carbon sequestration. Carbon sequestration was positively correlated with initial species richness of shade trees. Species diversity of shade trees did not change significantly over the study period, but carbon stocks increased due to tree growth. Our results show a potential for carbon sequestration and long‐term biodiversity conservation in smallholder coffee agroforestry systems and illustrate the opportunity for synergies between biodiversity conservation and climate change mitigation. Interacciones entre el Secuestro de Carbono y la Diversidad de Árboles de Sombra en una Cooperativa de Café de Pequeños Agricultores en El Salvador 相似文献
84.
BRENT J. SEWALL AMY L. FREESTONE MOHAMED F. E. MOUTUI NASSURI TOILIBOU ISHAKA SAÏD SAINDOU M. TOUMANI DAOUD ATTOUMANE CHEIKH M. IBOURA 《Conservation biology》2011,25(4):688-696
Abstract: Systematic conservation assessment (an information‐gathering and prioritization process used to select the spatial foci of conservation initiatives) is often considered vital to conservation‐planning efforts, yet published assessments have rarely resulted in conservation action. Conservation assessments may lead more directly to effective conservation action if they are reoriented to inform conservation decisions. Toward this goal, we evaluated the relative priority for conservation of 7 sites proposed for the first forest reserves in the Union of the Comoros, an area with high levels of endemism and rapidly changing land uses in the western Indian Ocean. Through the analysis of 30 indicator variables measured at forest sites and nearby villages, we assessed 3 prioritization criteria at each site: conservation value, threat to loss of biological diversity from human activity, and feasibility of reserve establishment. Our results indicated 2 sites, Yiméré and Hassera‐Ndrengé, were priorities for conservation action. Our approach also informed the development of an implementation strategy and enabled an evaluation of previously unexplored relations among prioritization criteria. Our experience suggests that steps taken to ensure the closer involvement of practitioners, include a broader range of social data, encourage stakeholder participation, and consider the feasibility of conservation action can improve the relevance of assessments for conservation planning, strengthen the scientific basis for conservation decisions, and result in a more realistic evaluation of conservation alternatives. 相似文献
85.
REED F. NOSS ERICA FLEISHMAN† DOMINICK A. DELLASALA‡ JOHN M. FITZGERALD§ MART R. GROSS MARTIN B. MAIN†† FIONA NAGLE‡‡ STACEY L. O'MALLEY JON ROSALES§§ 《Conservation biology》2009,23(4):825-833
Abstract: The Society for Conservation Biology (SCB) can enhance conservation of biodiversity in North America by increasing its engagement in public policy. Toward this end, the North America Section of SCB is establishing partnerships with other professional organizations in order to speak more powerfully to decision makers and taking other actions—such as increasing interaction with chapters—geared to engage members more substantively in science-policy issues. Additionally, the section is developing a North American Biodiversity Blueprint, which spans the continental United States and Canada and is informed by natural and social science. This blueprint is intended to clarify the policy challenges for protecting continental biodiversity, to foster bilateral collaboration to resolve common problems, and to suggest rational alternative policies and practices that are more likely than current practices to sustain North America's natural heritage. Conservation scientists and practitioners can play a key role by drawing policy makers' attention to ultimate, as well as proximate, causes of biodiversity decline and to the ecological and economic consequences of not addressing these threats. 相似文献
86.
矿区植被恢复方式对土壤微生物和酶活性的影响 总被引:8,自引:6,他引:2
矿区废弃地生态退化形势严峻,生态修复已成为矿区可持续发展的主要措施,土壤微生物和酶活性可作为评价土壤恢复质量的敏感因子.本研究将以山西省安太堡煤矿复垦区作为对象,分析植被恢复方式对土壤微生物和酶活的影响.结果表明,不同植被方式对土壤理化特征、参与氮代谢的3类菌群(固氮菌、硝化细菌和反硝化细菌)和4种酶活性(蔗糖酶、过氧化氢酶、脲酶和多酚氧化酶活)均有显著影响.土壤总氮含量与固氮菌和硝化细菌数量均显著相关,而与反硝化细菌不相关.多酚氧化酶活性与有机碳和总氮含量之间为负相关,而其它3种酶与有机碳和总氮之间呈正相关.通过主成分分析计算综合肥力指标,刺槐-油松混交林土壤综合肥力指标最高,而未复垦综合肥力指标最低.可见,刺槐-油松混交林是晋西北干旱区矿区复垦较为适宜的植被恢复模式. 相似文献
87.
88.
为了解我国主要湖泊沉积物中重金属的污染特征,通过搜集整理已公开发表的文献资料数据,分析了我国31个主要湖泊表层沉积物中As、Cd、Cr、Cu、Hg、Ni、Pb和Zn 8种重金属含量的平均值及其分布特征,并运用地累积指数法、潜在生态风险指数法对其污染程度进行评价。结果显示:我国31个湖泊的沉积物中As、Cd、Cr、Cu、Hg、Ni、Pb、Zn平均含量分别为16.39,0.497,6.29,36.89,0.076,35.37,99.52 mg/kg,大部分元素含量平均值的最大值分布区域较为分散。地累积指数评价结果表明:8种重金属的平均污染程度由高到低依次为Cd>Hg>Cu>Zn>As>Ni>Zn>Cr,Cd和Hg在多个湖泊沉积物中达中度到重污染。潜在生态风险指数评价结果表明:8种重金属的潜在生态风险系数从高到低依次为Cd>Hg>As>Cu>Pb>Ni>Cr>Zn。8种重金属的总地累积指数和综合潜在生态风险具有显著的地域差异(P0.05),表明我国主要湖泊具有各自不同的重金属污染特征。 相似文献
89.
90.
生态环境保护目标指标是环境保护和生态建设规划中的核心内容,制定科学合理的规划指标体系,能够确保规划各项重点任务顺利实施.通过回顾分析"十一五"、"十二五"环境保护和生态建设规划指标体系,结合广西环境现状和发展趋势,在与国家和广西同期规划、计划、方案等衔接基础上,研究提出广西"十三五"环境保护和生态建设规划指标体系,设置了环境质量改善、总量控制、污染治理、风险防范、生态保护和生态公共服务等6个方面共29个指标,以期更好地指导"十三五"环境保护和生态建设工作. 相似文献