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以卫星遥感影像为基础,运用"3S"技术,解译并统计了海南岛陆地自然生态系统的类型和面积,利用生态经济相关理论基础,评估计算出年海南岛陆地自然生态系统服务价值。结果表明,2008年海南岛自然生态系统服务价值约2198×108元,是当年全省GDP的1.5倍;森林生态系统的服务价值占四类生态系统(森林、草地、湿地和淡水)服务价值的81.77%,单位面积价值量达3260×104元/km2;自然生态系统在维持营养物质循环、水调节、大气调节等方面的间接使用价值约2076×108元,是直接使用价值的17.0倍。研究首次建立了针对海南岛陆地生态系统服务价值全面的评估体系,并在评估方法上择优、改进,对海南岛自然生态系统服务价值监测体系的构建及深入研究具有重要意义。  相似文献
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The over 300 million ha of public and private rangelands in the United States are characterized by low and variable precipitation, nutrient-poor soils, and high spatial and temporal variability in plant production. This land type has provided a variety of goods and services, with the provisioning of food and fiber dominating through much of the 20th century. More recently, food production from a rangeland-based livestock industry is often pressured for a variety of reasons, including poor economic returns, increased regulations, an aging rural population, and increasingly diverse interests of land owners. A shift to other provisioning, regulating, cultural, and supporting services is occurring with important implications for carbon sequestration, biodiversity, and conservation incentives. There are numerous goods and services possible from rangelands that can supply societal demands such as clean water and a safe food supply. The use of ecologically-based principles of land management remains at the core of the ability of private land owners and public land managers to provide these existing and emerging services. We suggest that expectations need to be based on a thorough understanding of the diverse potentials of these lands and their inherent limits. A critical provisioning service to rangelands will be management practices that either maintain ecological functions or that restore functions to systems that have been substantially degraded over past decades. With proper incentives and economic benefits, rangelands, in the U.S. or globally, can be expected to provide these historical and more unique goods and services in a sustainable fashion, albeit in different proportions than in the past.  相似文献
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在快速城镇化过程中,中国城市边缘区生态安全格局出现了自然生态与人文生态双重破坏的问题,研究基于复合生态平衡、生态空间活化、共建共享共赢的发展目标,提出以自然生态要素识别与敏感度分析、人文生态发展需求分析为基础,以自然与人文生态安全格局分区建构、复合生态空间耦合下的功能化发展指引为核心的城市边缘区生态安全格局重构方法框架,并结合铜陵城市边缘区——东湖地区规划建设展开理论应用与实践探索,为重构城市边缘区生态安全格局提供有益借鉴。  相似文献
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