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排序方式: 共有254条查询结果,搜索用时 31 毫秒
1.
漓江水生态系统问题研究   总被引:4,自引:0,他引:4  
本文分析指出,漓江水生态系统保护与修复的目标是保证桂林的水安全,核心在于对其价值的偏好和评估。同时,文章提出了修复的标准及其实现的关键技术和关键途径。  相似文献   
2.
Estimation of ecosystem service values is a hot area of research in ecological conservation and economics. However, the costs of these outputs are largely unknown. In this paper, we estimated the opportunity cost of water allocated to afforestation projects through mathematical modeling based on statistical data for all of China to provide support for restoration planning based on a fuller consideration of the true costs. To guide future ecological conservation and environmental policy development, we illustrate a neglected concept (ecosystem service costs) and use this concept to compare the ecological services provided by ecological restoration based on afforestation with those of restoration based on the conservation of natural vegetation using data obtained since 1949 in China. The results showed that afforestation and natural vegetation create annual costs related to use of the available water resources equal to 4800 and 3700 RMB ha−1, respectively, representing a water opportunity cost of 1100 RMB ha−1 for afforestation. This illustrates the rule that “there is no free lunch” for any service, including ecosystem services. Therefore, to support the development of more effective and sustainable environmental restoration policy, it will be necessary to evaluate the associated opportunity costs.  相似文献   
3.
North America has few cultural agricultural landscapes, and often commensurately poor governance arrangements for managing change in such settings. This research uses the Acadian dykelands of Nova Scotia, Canada, as an opportunity to explore the social and governance limits to coastal climate adaptation in ‘new world’ cultural agricultural landscapes, as well as inform local decision-making. Approximately half of Nova Scotia’s coastal wetlands were converted to dykeland in the 1600s, lowering local resilience to the increased frequency and storm severity anticipated with climate change. Today, dykelands protect a diversity of public and private interests, meanings and values, yet are controlled by the agricultural sector, which can no longer afford to maintain them all to 2050 climate projections. We report here on a representative online Q-methodology survey of 183 adult Nova Scotians in the spring of 2015. Respondents sorted 34 statements along a normal distribution about whether they prefer dykeland maintenance or wetland restoration, and under what governance arrangements. Four factors were derived: the dominant discourse was local, female and strongly pro-dykeland, indicating the likelihood for local resistance to dykeland removal on for cultural, recreational and farming reasons. The second factor was supportive of wetland restoration for reasons of efficiency, not wetland affinity, but characterized by those in positions of management power. The two minority viewpoints were less informed about dykelands, characteristic of outsiders, and concerned more with governance. More education is needed about the challenges facing dykelands, the benefits of coastal wetlands, and the management options, but this research shows proposals to change landscape should emphasize flood mitigation over cost-saving. Cultural values and status quo bias are clearly barriers to adaptation planning, even when discussing the removal of man-made structures. The factors were surprisingly polarized, suggesting the forced-normal distribution affects the space available to convey nuanced perspectives. Large p-set Q-method of this kind is likely most useful for characterizing the emergent discourses demographically, and understanding their prevalence; the same discourses had emerged within a much smaller pilot study.  相似文献   
4.
The forest and landscape restoration (FLR) targets set as part of the Bonn Challenge draw attention to the governance arrangements required to translate national FLR targets into local action. To achieve the targets, actors at multiple levels of the governance scale aim to influence relevant processes on the ecological scale. In this article, we focus on the scale challenges relating to the implementation of Ecuador’s restoration targets, by analysing the implementation of the 2014–2017 National Forest Restoration Plan in the montane Chocó Andino and Bosque Seco landscapes. From 54 semi-structured interviews, a document review, and geographical data analysis, we identified two temporal (i, ii) and three spatial scale challenges (iii, iv, v): i) Political cycles mismatch with FLR timelines; ii) Planning horizons mismatch with FLR timelines; iii) National restoration objectives mismatch with decentralised land use planning realities; iv) The governance level of existing FLR efforts mismatches with the level receiving restoration funds; and v) Tensions exist between the spatial dimensions of biodiversity and water-related restoration efforts. The findings highlight that more attention must be given to scale-sensitive governance to make the process in which national FLR targets are translated into local action more effective.  相似文献   
5.
本文在构建评价指标体系的基础上,对我国海洋渔业生态环境进行了综合评价,认为我国海洋渔业生态面临的失衡威胁正逐渐增强;并从自然和人为因素两个角度剖析了我国海洋渔业生态失衡的内在机理,并结合有关研究成果,构建了我国海洋渔业生态修复技术体系;最后,提出了防治我国海洋渔业生态失衡态势恶化的具体途径与措施。  相似文献   
6.
时瑾 《价值工程》2022,41(8):131-133
在水电水利工程建设当中,为了避免对周边环境造成一定的影响,管理部门需要加强对水土保持生态化建设的重视程度,根据水电水利工程的特点采取与之对应的生态修复方案,将水电水利工程对周边环境影响降到最低,以此来满足我国生态环境保护工作的要求以及标准,从而使水电水利工程能够朝着生态化以及绿色化的方向而不断的进步满足实际的应用要求,...  相似文献   
7.
通过对西安江村沟垃圾填埋场内及周边村民生活生产区共57处土壤进行实测与问卷调查,运用IPA分析方法,从村民景观生态感知角度出发,探讨村民对周边垃圾填埋场实际景观生态感知与期望之间的关系,以及影响村民景观生态感知的重要因素,得出景观生态满意度模型。对影响景观生态感知因素的重要性与满意度进行测量,同时生成IPA表现值与期望值,并以此为依据结合土壤实验结论,运用景观生态恢复技术,对垃圾填埋场的景观生态恢复提出了相关设计策略。  相似文献   
8.
论国土空间生态修复基本逻辑   总被引:9,自引:0,他引:9       下载免费PDF全文
研究目的:阐释国土空间生态修复的基本逻辑,支撑新时期国土空间生态修复从区域自主治理向全域空间设计的战略转型。研究方法:文献综述分析法,逻辑推理法,系统回顾法。研究结果:基于国土空间"要素—格局—过程—服务"级联框架及全域耦合关联,针对目标、对象、区位及途径厘清国土空间生态修复的基本逻辑:以提升人类生态福祉而非生态系统服务潜在供给增长为核心修复目标,国土空间社会—生态要素为基本修复对象,构建多尺度协同的生态安全格局识别重点修复地域,秉承多层级协同次优而非单层级最优的主导修复途径。研究结论:国土空间生态修复的本质在于修复人地冲突、强化人地协同,"修"的是人与自然不和谐的相处方式,"复"的是生态系统退化或受损的结构、过程、功能及服务;国土空间生态修复的对象、区位及途径均以修复目标为导向。  相似文献   
9.
研究目的:系统总结国外生态修复研究的重点进展和主流共识,为把握未来生态修复研究的前沿态势提供参考。研究方法:文献研究法。研究结果:按照生态修复的"目标导向—技术方法—成效评价"的框架进行梳理,现有研究在生态修复的对象及尺度、生态学及社会经济文化目标、各类型生态系统及要素的修复技术方法、成效评价维度及指标等方面取得了一定的研究进展,但总体而言,目前生态修复研究存在理论—实践—政策之间知识转移欠缺、生态学与社会经济学科交叉研究不足、全球气候变化背景下的研究缺乏等问题。研究结论:理论—实践—政策耦合研究、生态学—社会经济学科交叉研究、气候变化—生态修复联动研究等可能是未来生态修复领域的重点研究方向。  相似文献   
10.
通过对元谋干热河谷冲沟的立地条件和形成原因等方面的研究,把冲沟按垂直和流域方向各分成3个层次;根据各层次的特点进行林草配置,配置时充分考虑所选物种的生物学特性及生态学特性,并注重在植被恢复过程中的生态、经济和社会效益的和谐统一,以便达到较为理想的治理效果。  相似文献   
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