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121.
在大量野外工作的基础上 ,分析了徐州市的自然保护区建设现状 ,提出了建设策略 相似文献
122.
在地理信息系统(GIS)与遥感(RS)技术的支持下,选择多种定量指数对滇西北高原典型湿地区———碧塔海自然保护区进行了空间格局分析研究。通过分析,揭示了研究区景观空间格局的结构和特征及受扰程度,为研究区的湿地资源利用与保护提供了科学依据和决策支持。 相似文献
123.
Xie Genzong Qiu Penghua Tang Shaoxia 《中国人口.资源与环境(英文版)》2007,5(1):74-83
As the protected areas of land and coastal environment, nature reserves are designed to address how to reconcile the conservation of biodiversity, the quest for economic and social development and the maintenance of cultural values. This paper establishes a framework for nature reserve development that seeks to incorporate ecotourism into its strategies. The overall purpose was to identify the information needs required for a comprehensive nature reserve that incorporates ecotourism related values. It also illustrates the utility of this framework in the context of the Wuzhishan Mountain Region of China. A literature review, the first phase of a visionary strategy and a subsequent gap analysis for available management information were undertaken in order to achieve this paper's purpose. Finally, recommendations axe pre-sented for integrating ecotourism into nature reserve development in the Wuzhishan Mountain Region. 相似文献
124.
康东伟 《中国环境管理干部学院学报》2006,16(4):43-45
昌黎黄金海岸自然保护区存在着土地权属、资源保护与开发矛盾、经费不足和管理执法力量薄弱等诸多现实问题.因此,结合保护区概况,提出发展生态旅游,解决土地权属、协调资源保护与开发关系和实施社区共管等方式等可行性对策与措施. 相似文献
125.
Gorshkov V. V. Gorshkov V. G. Danilov-Danil'yan V. I. Losev K. S. Makar'eva A. M. 《Russian Journal of Ecology》2002,33(3):149-155
Closed systems are governed by the second law of thermodynamics and cannot spontaneously become more ordered. In open physical systems exposed to external energy flows, additional macroscopic degrees of freedom (memory cells) emerge, their number increasing with an increase in the flow and orderliness of the external energy. Biological systems are characterized by molecular degrees of freedom, the density of which is more than twenty orders of magnitude higher than that of macroscopic degrees of freedom in any open physical system exposed to the same external energy flow. This indicates that the self-organization of physical systems in external energy flows and the self-organization and evolution of living systems are fundamentally different. Thus, although life is an open system, the energy (food) flows that it consumes and all other external factors affecting life are so poorly ordered, compared to life itself, that they cannot increase the degree of order in the latter. Therefore, living systems obey an analogue of the second law of thermodynamics: within periods of time considerably shorter than the duration of evolutionary changes, living systems can only lose the accumulated information (i.e., the entropy can only increase), even if the systems consume external energy–food flows. 相似文献
126.
从自然资源和资源市场的角度提出资源储备的新概念,论述资源储备的内容及其意义,并在此基础上,探讨了建立四川资源储备制度的措施和方法。 相似文献
127.
长江口九段沙水域环境及生物体内多氯联苯分布 总被引:6,自引:1,他引:5
对长江口九段沙湿地自然保护区的滩涂水样、泥样以及水生生物体内的多氯联苯进行GC-MS检测,研究多氯联苯各单体在不同环境介质及生物体中的分布状况. 结果表明:水样、泥样中的多氯联苯检出率为100%,其中四氯联苯(PCB52)含量最高; 与其他河口地区相比,九段沙水域水体中多氯联苯(PCBs)含量处于中等水平,ρ(PCBs)为23~95 ng/L;滩涂泥样多氯联苯含量则较低,w(PCBs)为1.77~4.51 ng/g; 该水域水生生物多氯联苯检出率为100%,w(PCBs)为0.12~9.40 μg/kg,低于国家标准限量; 软体动物、甲壳类以及鱼类检出单体均以高氯类PCB118和PCB138为主,而非环境中含量较高的PCB52,反映了水生生物对于高氯类多氯联苯富集能力强于低氯类多氯联苯. 相似文献
128.
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
129.
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
130.
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