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961.
Ecosystems are essential in providing multiple services to society. However, understanding ecosystem services (ESS) in terms of spatial distribution and trade-offs still remains a challenge for landscape planners and natural resource managers. In this paper, we analyzed the supply of a set of ESS – carbon storage, soil erosion protection, biodiversity, and recreation – within the landscape surrounding the city of Bari in Southern Italy. Through an analysis of this landscape, which includes natural protected areas, such as Natura 2000 Network sites, national and regional parks and nature reserves, and in view of the recent Fitness Check of the Nature Directives, we aimed to provide answers to the following questions: (i) Where are the areas of high and low supply of individual ecosystem services located?; (ii) Where do ecosystem service trade-offs (i.e., ‘hotspots’ and ‘coldspots’) occur?; and (iii) To what extent are ecosystem service hotspots and coldspots located within or outside of natural protected areas? Results show that most of the landscape in the study area supplied at least one of the selected ESS and that ESS hotspots were mostly located within forested and/or natural areas. Hotspots occupied 8.0% of the total landscape, with 23.7% located in natural protected areas. Coldspots were scarce and equal to 2.4%; they constituted only 0.1% of natural protected areas. Almost all of the landscape (89.6%) consists of intermediate areas (i.e., between hotspots and coldspots); 76.2% of natural protected areas consists of intermediate areas. This latter finding is relevant because the high intermediate classes are potentially high-performing areas, which lie mainly on the borders of protected spaces; they can positively influence ecological processes and thus enhance a wide-ranging provision of ESS. Our results highlight the importance of analyzing landscapes to facilitate the selection of priority areas where management efforts would yield maximum benefits. 相似文献
962.
This article is based on an international comparative study analysing innovations in national administrative institutions.
Results of that research are presented and discussed here. Against the background of the institutionalising process of political
institutions the study focused on innovations initiated or introduced by governments or parliaments by example of policies
and politics supporting sustainable development. The countries involved in the original study were Belgium, Denmark, Finland,
France, Germany, the Netherlands, Sweden and the United Kingdom. Three general lessons can be drawn: (1) Countries with a
long tradition of integrated environmental policy-making are more open to the concept of sustainability. (2) A (institutional)
“cure-all” solution does not seem to exist. It seems necessary to diffuse the concept of sustainability into all spheres of
politics and society. Reaching this strategic goal requires a specific policy and polity mix. (3) Strong and well-equipped
institutions result from specific policies and politics: they play a central role in promoting and intensifying sustainable
development. Successful innovations integrating SD into everyday politics and policies are only a very first step though.
Further improvements with regard to effective participation and public debate, global orientation of policies and the measurability
of achieved progress are necessary. 相似文献
963.
Water sector reforms based on the concept of Integrated Water Resources Management (IWRM) are criticized for not considering context, local realities or legitimacy during the implementation of water sector reforms. Universal remedies of IWRM can thus lead to resistance, conflicts and ultimately failures of interventions. This paper examines how conflicts and disharmony can be addressed by IWRM's instruments. It conceptualizes institutional security as a highly relevant issue to be addressed during water management interventions. Further, the paper advocates a reform of the holistic concept of IWRM to incorporate ‘peace and security’ as a new pillar of water management based on a broad understanding of societal goals that are embedded in the principles of good governance and sustainable development. It also reviews recent criticism of and debates in IWRM and explains the advantages of expanding the normative idea behind it. 相似文献
964.
Mersie Ejigu 《Natural resources forum》2008,32(2):152-162
The past few years have seen a phenomenal rise in the production and consumption of biofuels and biodiesel at the global level. This development is of special significance to Africa, where about 550 million people (75% of the total population in Sub‐Saharan Africa) depend on traditional biomass (wood, charcoal, cow dung, etc.) and lack access to electricity or any kind of modern energy service. Derived from plants and agricultural crops, biofuels and biodiesel represent modern forms of bioenergy and more efficient use of biomass energy. Beyond efficiency, modern bioenergy offers tremendous opportunities to meet growing household energy demands, increase income, reduce poverty, and mitigate environmental degradation. In the African setting, energy and livelihoods security are indeed inseparable. This paper argues economic, social, and environmental benefits of modern bioenergy can be realized through a strategy that centres on smallholder production and processing schemes and pursuit of a livelihood approach to energy development. Such a scheme opens up new domestic markets, generates new cash incomes, improves social wellbeing, enhances new technology adoption, and lays the ground for rural economic transformation and sustainable land use. The paper concludes by underlining the vital importance of considering sound property rights and strategic planning of sustainable development as tools for sustainable energy and livelihoods security. 相似文献
965.
Julia Ohl Alexander Wezel Glenn H. Shepard Jr. Douglas W. Yu 《Environment, Development and Sustainability》2008,10(6):827-843
In this study, we investigate whether traditional swidden agriculture on nutrient-poor tropical soils can sustainably support
a growing indigenous population within Manu National Park, Peru. Based on interviews with 50 Matsigenka farmers, as well as
GPS mapping and field visits, we established the location and size of all 124 swidden gardens cultivated in 2000 and 2001.
Using a GIS-based soil map of Manu Park, we identify the total extent of potential arable land (1) throughout the park zones
currently available for Matsigenka habitation, and (2) within the vicinity of the two study communities. Taking into account
current per capita garden size, cultivation and fallow practices, we calculate the maximum human carrying capacity of swidden
agriculture for (1) all available park zones and (2) the immediate vicinity of the two current communities. Even given the
second, highly limited scenario, the sustainable human carrying capacity is estimated to be 2,138 individuals, which is far
higher than the current population of about 420 people. Thus, arable land does not appear to be a limiting factor for the
growth of the indigenous population in Manu Park at the current time. Other possible limiting factors for population growth
are identified and discussed. We conclude that a conservation policy of population stabilization around the current settlements
is viable in that it will not result in reduced resource availability over the next few decades, and that the challenge is
to identify and mitigate the forces causing population fissioning and spread.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
966.
江苏沿江城市群可持续发展的制约因素与取向 总被引:8,自引:0,他引:8
汤可可 《中国人口.资源与环境》1999,9(1):38-43
本文概括地描述了江苏沿江城市群发展特点,分析了城市群规模增大、结构优化、形态和功能演进的主要制约因素,并提出了城市群可持续发展的几点建议 相似文献
967.
矿化度是地下水化学成份测定的重要指标,在环境监测中,用重量法测定矿化度是目前普遍采用的方法。其缺点主要为费时,繁琐,耗电。本文通过测定洛阳市地下水的电导率,分析对比电导率与矿化度的关联,并进一步用回归方程确定电导率与矿化度之间的数量关系,探索出用电导率法间接测定地下水矿化度,具有快速,经济,准确的优点。 相似文献
968.
上海城市人为灾害的灰色预测 总被引:4,自引:0,他引:4
应用灰色预测GM(1,1)模型,导出其响应函数,对上海市的火灾发灾频次作了实例预测。然后对预测模型作了检验,预测精度是2级,检验结论符合要求。对城市人为灾害的灰色预测,为防灾减灾的决策部署提供了依据。 相似文献
969.
970.
朱庚申 《中国环境管理干部学院学报》1999,(1)
农业可持续发展是国家可持续发展的根本保证和优先领域,实现农业可持续发展必须建立可持续农业。本文认为,高科技生态农业是中国可持续农业的唯一战略选择和最终出路。为实现这一战略选择,在继续贯彻实施计划生育和环境保护两个基本国策的同时,必须调整现有的农业结构和资源管理模式,制定可持续利用的资源管理政策,发展以生态农业为基础、以高新农业技术为手段的高科技生态农业。 相似文献