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991.
中国西部城市化基本特征分析——以新疆为例 总被引:2,自引:0,他引:2
孙建丽 《中国人口.资源与环境》2000,10(4):54-57
本文以新疆为例,探讨了新疆城市化的基本特征和规律,总结经验教训,以朝正确认识西部地区城市化的基本特征,从而为西部大开发中城市化发展战略的制定提供有价值的借鉴和参考。 相似文献
992.
Marine protected areas (MPAs) have become a key component of conservation and fisheries management to alleviate anthropogenic pressures. For MPA networks to efficiently promote persistence and recovery of populations, ecological connectivity, i.e. dispersal and movement of organisms and material across ecosystems, needs to be taken into account. To improve the ecological coherence of MPA networks, there is hence a need to evaluate the connectivity of species spreading through active migration and passive dispersal. We reviewed knowledge on ecological connectivity in the Baltic Sea, Kattegat and Skagerrak in the northeast Atlantic and present available information on species-specific dispersal and migration distances. Studies on genetic connectivity are summarised and discussed in relation to dispersal-based analyses. Threats to ecological connectivity, limiting dispersal of populations and lowering the resilience to environmental change, were examined. Additionally, a review of studies evaluating the ecological coherence of MPA networks in the Baltic Sea, Kattegat and Skagerrak was performed, and suggestions for future evaluations to meet management needs are presented.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01684-x. 相似文献
993.
Marine protected areas (MPAs) are considered as a valid tool for mitigating the impact of fishing on marine ecosystems. Their success depends upon their acceptance by implicated stakeholders and on the integration of the stakeholder groups into their management. This integration is especially important with regard to fishermen, whose interests are the most directly affected by MPAs. The relational coordination method posits that effective communication and supportive relationships among stakeholders result in positive stakeholder behaviors and a more effective management of the system. Applying its principles, we designed a survey to evaluate the satisfaction of fishermen associated with five MPAs in the Spanish Mediterranean and determine what mechanisms affect fishermen’s acceptance of MPAs. Our results demonstrate that effective communication is particularly important for good supportive relationships and satisfaction among fishermen and other stakeholder groups, as well as satisfaction with the MPA. Sharing objectives with fishermen through timely communication is the primary mechanism to improve fishermen''s satisfaction and ameliorate perceptions towards MPA. To address this issue, we recommend more substantial integration of fishermen in the co-management of MPAs. 相似文献
994.
995.
Gaps and opportunities for the World Heritage Convention to contribute to global wilderness conservation 下载免费PDF全文
James R. Allan Cyril Kormos Tilman Jaeger Oscar Venter Bastian Bertzky Yichuan Shi Brendan Mackey Remco van Merm Elena Osipova James E.M. Watson 《Conservation biology》2018,32(1):116-126
Wilderness areas are ecologically intact landscapes predominantly free of human uses, especially industrial‐scale activities that result in substantial biophysical disturbance. This definition does not exclude land and resource use by local communities who depend on such areas for subsistence and bio‐cultural connections. Wilderness areas are important for biodiversity conservation and sustain key ecological processes and ecosystem services that underpin planetary life‐support systems. Despite these widely recognized benefits and values of wilderness, they are insufficiently protected and are consequently being rapidly eroded. There are increasing calls for multilateral environmental agreements to make a greater and more systematic contribution to wilderness conservation before it is too late. We created a global map of remaining terrestrial wilderness following the established last‐of‐the‐wild method, which identifies the 10% of areas with the lowest human pressure within each of Earth's 62 biogeographic realms and identifies the 10 largest contiguous areas and all contiguous areas >10,000 km2. We used our map to assess wilderness coverage by the World Heritage Convention and to identify gaps in coverage. We then identified large nationally designated protected areas with good wilderness coverage within these gaps. One‐quarter of natural and mixed (i.e., sites of both natural and cultural value) World Heritage Sites (WHS) contained wilderness (total of 545,307 km2), which is approximately 1.8% of the world's wilderness extent. Many WHS had excellent wilderness coverage, for example, the Okavango Delta in Botswana (11,914 km2) and the Central Suriname Nature Reserve (16,029 km2). However, 22 (35%) of the world's terrestrial biorealms had no wilderness representation within WHS. We identified 840 protected areas of >500 km2 that were predominantly wilderness (>50% of their area) and represented 18 of the 22 missing biorealms. These areas offer a starting point for assessing the potential for the designation of new WHSs that could help increase wilderness representation on the World Heritage list. We urge the World Heritage Convention to ensure that the ecological integrity and outstanding universal value of existing WHS with wilderness values are preserved. 相似文献
996.
In the face of the current global ecological crisis and the threats it poses to human survival and security, the fundamental solution is to resolve the deep contradiction between conservation and economic development. We considered the 3 key and basic questions of why to protect, how much to protect, and where to protect natural areas. Human survival depends on functioning ecosystems and the ecosystem services they provide. In this regard, conserving core biodiversity conservation priority areas (BCPAs) can provide maximum conservation benefit. The goals of protected area (PA) systems globally and nationally must be clearly defined so as to sustain the survival and development of people and to coordinate and balance other objectives with this goal at the center. There is an urgent need to study, calculate, and define the extent of the natural world to ensure the well-being of people. We call this area over which natural areas of land and sea extend across the world or a country nature proportion (N%). Especially, a minimum area that ensures human survival should be protected, and we suggest that this area should cover core BCPAs so that it can achieve the maximum conservation benefit. These recommendations could be applied at global or national levels. The Chinese government proposes “developing a protected-area system composed mainly of national parks,” and it has unified the administration of PAs into a central management authority. At this key time in the reform of the PA system, should this proposal be adopted, conservation will garner the greatest social consensus and support, and planning at the national level for BCPA coverage will be improved. We believe these recommendations are critical for China and other countries and extremely important for the world because they will pave the way toward a balance between nature conservation and human development as the projected human population reaches 10 billion by 2050. 相似文献
997.
Katharine R. E. Sims Jonathan R. Thompson Spencer R. Meyer Christoph Nolte Joshua S. Plisinski 《Conservation biology》2019,33(5):1035-1044
Land protection, whether public or private, is often controversial at the local level because residents worry about lost economic activity. We used panel data and a quasi-experimental impact-evaluation approach to determine how key economic indicators were related to the percentage of land protected. Specifically, we estimated the impacts of public and private land protection based on local area employment and housing permits data from 5 periods spanning 1990–2015 for all major towns and cities in New England. To generate rigorous impact estimates, we modeled economic outcomes as a function of the percentage of land protected in the prior period, conditional on town fixed effects, metro-region trends, and controls for period and neighboring protection. Contrary to narratives that conservation depresses economic growth, land protection was associated with a modest increase in the number of people employed and in the labor force and did not affect new housing permits, population, or median income. Public and private protection led to different patterns of positive employment impacts at distances close to and far from cities, indicating the importance of investing in both types of land protection to increase local opportunities. The greatest magnitude of employment impacts was due to protection in more rural areas, where opportunities for both visitation and amenity-related economic growth may be greatest. Overall, we provide novel evidence that land protection can be compatible with local economic growth and illustrate a method that can be broadly applied to assess the net economic impacts of protection. 相似文献
998.
Rosa María Pérez-Pastor Susana García-Alonso Alberto José Quejido Cabezas 《Environmental science and pollution research international》1999,6(3):141-146
From November 1995 to October 1996, airborne concentrations of VOCs were measured in the Madrid area to study the organic
pollution in general, and the correlation between different pollutants in relation to such parameters as location and season.
Mean concentrations for up to 90 compounds were measured at four test sites, including both urban and suburban areas.
At the urban sites, maximum concentrations occurred in the autumn and winter, whereas minimum concentrations were reached
in summer and spring. Similar changes were obtained for the lesscontaminated site located in the SE of the city, whereas a
different pattern was found at the site in the NW of the city due to meteorological aspects. Mean levels of hydrocarbons in
Madrid were quite similar to those found in other European cities.
Chemometrical techniques were applied to the set of data in order to assess the influence of such factors as traffic, temperature
and seasonal variations on the VOC levels. 相似文献
999.
1000.
Protected areas present a global heritage. Assessing conservation achievements in protected areas is of crucial importance with respect to the on-time delivery of international biodiversity conservation targets. However, monitoring data from publicly accessible databases for comparative studies of conservation achievements in the protected areas of the world are very scarce, if not non-existent. At first glance this is surprising because, with regards to protected areas, at least according to well established protected area management guidelines and widely accepted public mandates, a great deal of monitoring work and data gathering is to be conducted. This would imply that data on changes of biodiversity in protected areas could be expected to exist, and the constant progress in information technologies and Web tools engenders hope that some of it might even be available online for the global public. This review article presents the results of an extensive online search and review of existing monitoring data from freely accessible online databases for its use in an assessment of conservation achievements in a larger sample of protected areas. Results show two contrary sides to the status quo of accessible data from the World Wide Web for conservation science: data overkill and data scarcity with poor metadata provision. While ever more research is, in fact, based on open-access online data, such as extrapolations of species ranges used in conservation management and planning, it remains almost impossible to obtain a basic set of information for an assessment of conservation achievements within a larger number of protected areas. This awareness has triggered a detailed discussion about the discrepancies in sharing data at the level of protected areas; mismatching relationships between expected activities in protected areas and the capacity for delivering these requirements are certainly among the main challenges. In addition, the fear of data misuse potentially resulting in harm for nature, careers, and competencies still seems to be a critical barrier strictly controlling the willingness to share data. Various initiatives aimed at tackling technical and cultural obstacles are introduced and discussed to reach the goal of a modern resource management based on adaptive management using digital opportunities of the new millennium for a sustainable global village. 相似文献