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931.
长江上游流域生态与可持续发展对策   总被引:2,自引:0,他引:2  
概述了长江上游流域生态环境退化的现状和急需解决的问题,分析了生态环境退化的人为驱动因素和生态建设存在的问题,在此基础上提出了将长江上游作为一个流域整体进行跨地区、跨部门、跨学科的大联合攻关,强调“快速、经济、参与”为指导思想和原则,突出重点生态类型区域,开展关键技术试验示范攻关,发展以资源导向为主的区域经济,从而实现“近期遏制恶化,中期治理恢复,最终持续发展”的分阶段目标。  相似文献   
932.
西部大开发与聚落生态建设——以西南山区为例   总被引:2,自引:0,他引:2  
我国西部生态环境退化与广泛分布的农村聚落落后的生产方式和生活方式有密切关系。在西部大开发中 ,搞好生态环境必须与聚落建设统一规划 ,同步实施。重点应解决好环境恶劣的聚落、地方病聚落、自然保护区聚落、草场聚落、工程移民聚落。根据不同生态状况 ,可采取新建聚落、重建聚落与迁建聚落等聚落建设方略  相似文献   
933.
陕北能源开发区城镇生态环境建设战略   总被引:1,自引:0,他引:1  
根据国内外城市发展趋势和我国城镇生态建设的基本要求,对陕北原源开发区城镇生态环境建设提出了战略性看法和建议。  相似文献   
934.
Izquierdo AE  Grau HR  Aide TM 《Ambio》2011,40(3):298-309
Global trends of increasing rural–urban migration and population urbanization could provide opportunities for nature conservation, particularly in regions where deforestation is driven by subsistence agriculture. We analyzed the role of rural population as a driver of deforestation and its contribution to urban population growth from 1970 to the present in the Atlantic Forest of Argentina, a global conservation priority. We created future land-use-cover scenarios based on human demographic parameters and the relationship between rural population and land-cover change between 1970 and 2006. In 2006, native forest covered 50% of the province, but by 2030 all scenarios predicted a decrease that ranged from 18 to 39% forest cover. Between 1970 and 2001, rural migrants represented 20% of urban population growth and are expected to represent less than 10% by 2030. This modeling approach shows how rural–urban migration and land-use planning can favor nature conservation with little impact on urban areas.  相似文献   
935.
Modelling nitrogen transfer and transformation at the landscape scale is relevant to estimate the mobility of the reactive forms of nitrogen (Nr) and the associated threats to the environment. Here we describe the development of a spatially and temporally explicit model to integrate Nr transfer and transformation at the landscape scale. The model couples four existing models, to simulate atmospheric, farm, agro-ecosystem and hydrological Nr fluxes and transformations within a landscape. Simulations were carried out on a theoretical landscape consisting of pig-crop farms interspersed with unmanaged ecosystems. Simulation results illustrated the effect of spatial interactions between landscape elements on Nr fluxes and losses to the environment. More than 10% of the total N2O emissions were due to indirect emissions. The nitrogen budgets and transformations of the unmanaged ecosystems varied considerably, depending on their location within the landscape. The model represents a new tool for assessing the effect of changes in landscape structure on Nr fluxes.  相似文献   
936.
Around the globe, human behavior and ecosystem health have been extensively and sometimes severely affected by the unprecedented COVID-19 pandemic. Most efforts to study these complex and heterogenous effects to date have focused on public health and economics. Some studies have evaluated the pandemic’s influences on the environment, but often on a single aspect such as air or water pollution. The related research opportunities are relatively rare, and the approaches are unique in multiple aspects and mostly retrospective. Here, we focus on the diverse research opportunities in disease ecology and ecosystem sustainability related to the (intermittent) lockdowns that drastically reduced human activities. We discuss several key knowledge gaps and questions to address amid the ongoing pandemic. In principle, the common knowledge accumulated from invasion biology could also be effectively applied to COVID-19, and the findings could offer much-needed information for future pandemic prevention and management.  相似文献   
937.
South Africa's moist grassland harbours globally significant biodiversity, supplies essential ecosystem services, supports crop and livestock agriculture, forestry and settlement, yet is poorly conserved. Ongoing transformation and limited opportunity for expanding the protected area network require instead that biodiversity conservation is 'mainstreamed' within other land uses. This exercise sought to identify the relative compatibility of 10 land uses (conservation, livestock or game ranching, tourism/recreation, rural settlement, dryland cropping, irrigated cropping, dairy farming, plantation forestry, and urban settlement) with maintaining biodiversity integrity. This was assessed using 46 indicators for biodiversity integrity that covered landscape composition, structure, and functioning. Data was integrated into a single measure per land use through application of the analytic hierarchy process, with supporting information gained from interviews with experts. The rank order of importance amongst indicators was landscape structure, functioning and composition. Consistent differences among land uses for all three categories revealed two clear groupings. Conservation, livestock or game ranching had the lowest impact and retained substantial natural asset, while that for tourism/recreation was intermediate. All other land uses had a severe impact. Impact on biodiversity integrity depended mainly on the extent of transformation and fragmentation, which accounted for the greatest impact on habitats and species, and impairment of landscape functioning. It is suggested that a strategic intervention for maintaining biodiversity integrity of moist grassland is to support livestock or game ranching and limit ongoing urban sprawl.  相似文献   
938.
This study evaluated the impact of small boat traffic on reaction distances of Marbled Murrelets (Brachyramphus marmoratus), in the marine waters of Pacific Rim National Park Reserve, British Columbia, Canada. Observers on moving boats recorded the minimum distance the boat came to murrelets on the water, and any disturbance reaction (fly, dive, no reaction). Out of the 7500 interactions 11.7% flew, 30.8% dove and 58.1% exhibited no flushing reaction. Using a product-limit analysis, we developed curves for the proportion of Marbled Murrelets flushing (dive or flight) as a function of reaction distance. Overall, the majority of Marbled Murrelets waited until boats were within 40 m before reacting, with 25% of the population reacting at 29.2m. A stepwise Cox regression indicated that age, boat speed, and boat density (loaded in that order), significantly affected flushing response. More juveniles flushed than adults (70.1 versus 51.7%), but at closer distances. Faster boats caused a greater proportion of birds to flush, and at further distances (25% of birds flushed at 40 m at speeds > 29 kph versus 28m at speeds <12kph). A stepwise logistic regression on diving and flight responses indicated that birds tended to fly completely out of feeding areas at the approach of boats travelling >28.8 kph and later in the season (July and August). Other secondary variables included; boat density and time of day. Discussion focused on possible management actions such as the application of speed limits, set back distances, and exclusion of boat traffic to protect Marbled Murrelets.  相似文献   
939.
Current ecological thinking emphasizes that systems are complex, dynamic, and unpredictable across space and time. What is the diversity in interpretation of these ideas among today’s ecologists, and what does this mean for environmental management? This study used a Policy Delphi survey of ecologists to explore their perspectives on a number of current topics in ecology. The results showed general concurrence with nonequilibrium views. There was agreement that disturbance is a widespread, normal feature of ecosystems with historically contingent responses. The importance of recognizing multiple levels of organization and the role of functional diversity in environmental change were also widely acknowledged. Views differed regarding the predictability of successional development, whether “patchiness” is a useful concept, and the benefits of shifting the focus from species to ecosystem processes. Because of their centrality to environmental management, these different views warrant special attention from both managers and ecologists. Such divergence is particularly problematic given widespread concerns regarding the poor linkages between science (here, ecology) and environmental policy and management, which have been attributed to scientific uncertainty and a lack of consensus among scientists, both jeopardizing the transfer of science into management. Several suggestions to help managers deal with these differences are provided, especially the need to interpret broader theory in the context of place-based assessments. The uncertainty created by these differences requires a proactive approach to environmental management, including clearly identifying environmental objectives, careful experimental design, and effective monitoring.  相似文献   
940.
Site-specific estimates of the values of spatial configuration and forest composition are presented. Amenity values of forest patches are found to vary the most by urban and sprawling development patterns of specific areas and forest types. For example, smaller patches of deciduous forest are more highly valued in the urban and sprawling areas of Greensboro, North Carolina, whereas larger patches of deciduous forest are more highly valued in the urban and sprawling areas of Greenville, South Carolina. Within the Greenville and Greensboro areas, visible landscape complexity is highly valued for deciduous and evergreen forest patches, whereas lower visible landscape complexity, i.e., smoothly trimmed forest patch boundaries, is highly valued for mixed forest patches.  相似文献   
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