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211.
Coral Reef Habitats as Surrogates of Species, Ecological Functions, and Ecosystem Services 总被引:3,自引:0,他引:3
PETER J. MUMBY††† KENNETH BROAD† DANIEL R. BRUMBAUGH‡§ CRAIG P. DAHLGREN ALASTAIR R. HARBORNE ALAN HASTINGS†† KATHERINE E. HOLMES‡ CARRIE V. KAPPEL‡‡ FIORENZA MICHELI§§ JAMES N. SANCHIRICO 《Conservation biology》2008,22(4):941-951
Abstract: Habitat maps are often the core spatially consistent data set on which marine reserve networks are designed, but their efficacy as surrogates for species richness and applicability to other conservation measures is poorly understood. Combining an analysis of field survey data, literature review, and expert assessment by a multidisciplinary working group, we examined the degree to which Caribbean coastal habitats provide useful planning information on 4 conservation measures: species richness, the ecological functions of fish species, ecosystem processes, and ecosystem services. Approximately one‐quarter to one‐third of benthic invertebrate species and fish species (disaggregated by life phase; hereafter fish species) occurred in a single habitat, and Montastraea‐dominated forereefs consistently had the highest richness of all species, processes, and services. All 11 habitats were needed to represent all 277 fish species in the seascape, although reducing the conservation target to 95% of species approximately halved the number of habitats required to ensure representation. Species accumulation indices (SAIs) were used to compare the efficacy of surrogates and revealed that fish species were a more appropriate surrogate of benthic species (SAI = 71%) than benthic species were for fishes (SAI = 42%). Species of reef fishes were also distributed more widely across the seascape than invertebrates and therefore their use as a surrogate simultaneously included mangroves, sea grass, and coral reef habitats. Functional classes of fishes served as effective surrogates of fish and benthic species which, given their ease to survey, makes them a particularly useful measure for conservation planning. Ecosystem processes and services exhibited great redundancy among habitats and were ineffective as surrogates of species. Therefore, processes and services in this case were generally unsuitable for a complementarity‐based approach to reserve design. In contrast, the representation of species or functional classes ensured inclusion of all processes and services in the reserve network. 相似文献
212.
Katrina Davis Marit Kragt Stefan Gelcich Steven Schilizzi David Pannell 《Conservation biology》2015,29(1):226-237
Marine fish stocks are in many cases extracted above sustainable levels, but they may be protected through restricted‐use zoning systems. The effectiveness of these systems typically depends on support from coastal fishing communities. High management costs including those of enforcement may, however, deter fishers from supporting marine management. We incorporated enforcement costs into a spatial optimization model that identified how conservation targets can be met while maximizing fishers’ revenue. Our model identified the optimal allocation of the study area among different zones: no‐take, territorial user rights for fisheries (TURFs), or open access. The analysis demonstrated that enforcing no‐take and TURF zones incurs a cost, but results in higher species abundance by preventing poaching and overfishing. We analyzed how different enforcement scenarios affected fishers’ revenue. Fisher revenue was approximately 50% higher when territorial user rights were enforced than when they were not. The model preferentially allocated area to the enforced‐TURF zone over other zones, demonstrating that the financial benefits of enforcement (derived from higher species abundance) exceeded the costs. These findings were robust to increases in enforcement costs but sensitive to changes in species’ market price. We also found that revenue under the existing zoning regime in the study area was 13–30% lower than under an optimal solution. Our results highlight the importance of accounting for both the benefits and costs of enforcement in marine conservation, particularly when incurred by fishers. Justificación de los Costos de Aplicación en la Asignación Espacial de Zonas Marinas 相似文献
213.
ANDREW D. OLDS ROD M. CONNOLLY KYLIE A. PITT PAUL S. MAXWELL SHANKAR ASWANI SIMON ALBERT 《Conservation biology》2014,28(4):982-991
Conservation focuses on maintaining biodiversity and ecosystem functioning, but gaps in our knowledge of species biology and ecological processes often impede progress. For this reason, focal species and habitats are used as surrogates for multispecies conservation, but species‐based approaches are not widely adopted in marine ecosystems. Reserves in the Solomon Islands were designed on the basis of local ecological knowledge to conserve bumphead parrotfish (Bolbometopon muricatum) and to protect food security and ecosystem functioning. Bumphead parrotfish are an iconic threatened species and may be a useful surrogate for multispecies conservation. They move across tropical seascapes throughout their life history, in a pattern of habitat use that is shared with many other species. We examined their value as a conservation surrogate and assessed the importance of seascape connectivity (i.e., the physical connectedness of patches in the seascape) among reefs, mangroves, and seagrass to marine reserve performance. Reserves were designed for bumphead parrotfish, but also enhanced the abundance of other species. Integration of local ecological knowledge and seascape connectivity enhanced the abundance of 17 other harvested fish species in local reserves. This result has important implications for ecosystem functioning and local villagers because many of these species perform important ecological processes and provide the foundation for extensive subsistence fisheries. Our findings suggest greater success in maintaining and restoring marine ecosystems may be achieved when they are managed to conserve surrogate species and preserve functional seascape connections. Incorporación de Especies Sustitutas y de Conectividad Marina para Mejorar los Resultados de Conservación 相似文献
214.
Efficient and equitable design of marine protected areas in Fiji through inclusion of stakeholder‐specific objectives in conservation planning 下载免费PDF全文
Robert L. Pressey Natalie C. Ban Jorge G. Álvarez‐Romero Stacy Jupiter Vanessa M. Adams 《Conservation biology》2015,29(5):1378-1389
The efficacy of protected areas varies, partly because socioeconomic factors are not sufficiently considered in planning and management. Although integrating socioeconomic factors into systematic conservation planning is increasingly advocated, research is needed to progress from recognition of these factors to incorporating them effectively in spatial prioritization of protected areas. We evaluated 2 key aspects of incorporating socioeconomic factors into spatial prioritization: treatment of socioeconomic factors as costs or objectives and treatment of stakeholders as a single group or multiple groups. Using as a case study the design of a system of no‐take marine protected areas (MPAs) in Kubulau, Fiji, we assessed how these aspects affected the configuration of no‐take MPAs in terms of trade‐offs between biodiversity objectives, fisheries objectives, and equity in catch losses among fisher stakeholder groups. The achievement of fisheries objectives and equity tended to trade‐off concavely with increasing biodiversity objectives, indicating that it is possible to achieve low to mid‐range biodiversity objectives with relatively small losses to fisheries and equity. Importantly, the extent of trade‐offs depended on the method used to incorporate socioeconomic data and was least severe when objectives were set for each fisher stakeholder group explicitly. We found that using different methods to incorporate socioeconomic factors that require similar data and expertise can result in plans with very different impacts on local stakeholders. 相似文献
215.
Culturomic tools enable the exploration of trends in human–nature interactions, although they entail inherent biases and necessitate careful validation. Furthermore, people may engage with nature across different culturomic data sets differently. We evaluated people's digital interest and engagement with plant species based on Wikipedia and Google data and explored the conservation implications of these temporal interest patterns. As a case study, we explored the digital footprints of the most popular plant species in Israel. We analyzed 4 years of daily page views from Hebrew Wikipedia and 10 years of daily Google search volume in Israel. We modeled popularity of plant species in these 2 data sets based on a suite of plant attributes. We further explored the seasonal trends of people's interest in each species. We found differences in how people interacted digitally with plants in Wikipedia and Google. Overall, in Google, searches for species that have utility to humans were more common, whereas in Wikipedia, plants that serve as cultural emblems received more attention. Furthermore, in Google, popular species attracted more attention over time, opposite to the trend in Wikipedia. In Google, interest in species with short bloom duration exhibited more pronounced seasonal patterns, whereas in Wikipedia, seasonality of interest increased as bloom duration increased. Together, our results suggest that people's digital interactions with nature may be inherently different depending on the sources explored, which may affect use of this information for conservation. Although culturomics holds much promise, better understanding of its underpinnings is important when translating insights into conservation actions. 相似文献
216.
对辽宁、吉林、黑龙江三省(简称东三省)51个国家级自然保护区人类活动情况进行了实地考察,并对自然保护区的建’设和管理情况进行了调研。针对调研情况,为加强东三省国家级自然保护区管理工作的顺利进行,提出了相应的建议。 相似文献
217.
城区天然气管道泄漏数值模拟与爆炸危害分析 总被引:1,自引:0,他引:1
马世海 《中国安全生产科学技术》2011,7(7):26-30
在人口密度为三级和四级的城区内,密集的高建筑物对天然气管道泄漏后的扩散和流场形成产生重要影响。本文以某城市的实际情况为例,建立多建筑物的空间几何模型,采用k-ε湍流方程,SIMPLE算法,模拟了在三种不同风流速度、三种不同压力条件下,城区天然气管道泄漏气体在多建筑物地形中的扩散情况。根据模拟结果,依据天然气的爆炸极限,对模拟结果及其火灾爆炸危害的范围进行了对比分析。结果表明,CH4气体的泄漏扩散同时受管道压力、风流速度和周围建筑物的影响;同时受当地风速的影响,泄漏气柱在风流作用下会发生偏折,造成阻挡风流的建筑物内侧危险气体浓度升高,大大增加建筑物周围环境的危险性。研究结果对城区天然气管道的建设具有一定的指导意义。 相似文献
218.
对比分析了国内外环保投资范围的界定原则,解析了环保投资的内涵,从环保投资的性质、目的和内涵等方面提出了环保投资的界定原则。研究表明,目前我国环保投资统计口径比较混乱,环保投资虚高,且投资结构不尽合理,资金使用效率不高,造成污染治理和生态恢复速度一直滞后于环境污染和生态破坏速度。建议明晰环保投资定位,优化投资结构,明确投资范围,统一统计口径,拓宽投资融资渠道,保障投资金额,加强投资监管,提高投资使用效率,解决现有环境问题。 相似文献
219.
220.
基于层次分析法的应急物资储备方式研究 总被引:2,自引:1,他引:1
科学合理的应急物资储备是有效应对突发事件的重要保障。在综合考虑影响应急物资储备的主要因素的基础上,将应急物资分5类;界定了3类应急物资储备方式;采用层次分析对应急物资的储备方式进行了研究,结果表明,不同类型应急物资的储备方式有较大差别,食品药品类物资应以合同储备和生产能力储备为主;应急救援类物资应以实物储备为主;灾民安置类物资应以实物储备和生产能力储备为主;基础保障类物资应以实物储备和合同储备为主;大型设备类物资主要采用合同储备;从总体上来说,应急物资储备需要采用全面综合储备的方式,而不能偏颇。 相似文献