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101.
Difficulties in identifying actual uses of land space from remote sensing-based land cover products often result in lost opportunities to enhance the capacity of applied research on human settlements. In an attempt to address these difficulties, this study investigates how land cover and land use are interrelated with each other and what determines the relationship patterns by analyzing detailed land use and land cover data for two large US metropolitan areas – the five-county Los Angeles and six-county Chicago regions – where a broad spectrum of human settlements, ranging from urban cores to less-urbanized edges, coexist. The analysis shows that the land cover-land use relationship substantially varies not only across regions but across neighborhoods within each region. Through multivariate regression, it is also found that the intraregional variation is highly associated with the neighborhood's stage of urbanization, median housing age, and other development characteristics, suggesting that the relationship pattern can largely be shaped by the history and evolution of urban design/development.  相似文献   
102.
中国喀斯特天坑研究起源、进展与展望   总被引:5,自引:0,他引:5  
喀斯特天坑是20世纪末首先在中国南方峰丛和峰林喀斯特地区中发现的一种特殊且宏大的地表负地形,由于具有独特的科学价值和旅游价值,自被发现以来便引起了国内外地貌学者和地质学者的高度关注。对于喀斯特天坑(tiankeng)能否显著区别于其它普通漏斗,而成为一种独立的喀斯特地貌类型,国内外学者已从形态学、成因学、演化发生学等方面进行了深入探究,但仍未取得完全共识。国内外学者在其分类、形成与演化机制、发育条件、地质年代判定、岩溶生态环境等一系列问题上,也进行了较深入的探讨与激烈的争论。同时,对于喀斯特天坑价值的讨论以及开发与保护方面的研究也正引起国内外学者越来越多的关注。为此,论文围绕中国喀斯特天坑的研究阶段、研究进展、价值和开发与保护等主要议题进行了系统性的梳理与评述,进而提出中国喀斯特天坑当前研究中存在的问题和未来的研究方向。  相似文献   
103.
The Forest Landscape Model (FLM) is an efficiency tool of quantified expression of forest ecosystem''s structure and function. This paper, on the basis of identifying FLM, according to the stage of development, summarizes the development characteristics of the model, which includes the theoretical foundation of mathematical model, FLM of stand-scale, primary development of spatial landscape model, rapid development of ecosystem process model as the priority, and developing period of structure and process driven by multi-factor. According to the characteristics of different FLMs, this paper classifies the existing FLM in terms of mechanism, property and application, and elaborates the identifications, advantages and disadvantages of different types of models. It summarizes and evaluates the main application fields of existing models from two aspects which are the changes of spatial pattern and ecological process. Eventually, this paper presents FLM''s challenges and directions of development in the future, including: (1) more prominent service on the practical strategy of forest management''s objectives; (2) construction of multi-modules and multi-plugin to satisfy landscape research demand in various conditions; (3) adoption of high resolution''s spatial-temporal data; (4) structural construction of multi-version module; (5) improving the spatial suitability of model application.  相似文献   
104.
激光拉曼光谱法在单个流体包裹体研究中的应用进展   总被引:2,自引:2,他引:0  
何佳乐  潘忠习  冉敬 《岩矿测试》2015,34(4):383-391
激光拉曼光谱法以其非破坏性、高灵敏度和高分辨率等特性,一直以来都是研究流体包裹体的重要方法之一。近年来,围绕激光拉曼光谱在流体包裹体中的应用而展开的研究主要集中在半定量-定量测试方面,即在准确定性的基础上,采用高斯-洛仑兹去卷积分峰、低温原位等定量方法获取流体包裹体的成分和含量,从而克服了激光拉曼光谱法应用于溶液中阳离子的定量分析的灵敏度、准确度较低的问题,不仅能获得流体包裹体中一些常温下不具拉曼活性的盐类物质拉曼特征峰信息,还能根据特征峰与浓度、内压之间的线性关系,进一步对盐度和压力等性质进行测定,从而拓展了激光拉曼光谱法在流体包裹体中的应用范围。本文对激光拉曼光谱法应用于分析流体包裹体成分、盐度、同位素和压力所取得的最新进展进行了评述,并认为随着分析测试技术的不断进步,激光拉曼光谱法未来的分析方向也将继续围绕多元复杂体系及其定量方面的研究展开。  相似文献   
105.
As Payments for Ecosystem Services (PES) continues to gain attention as a policy tool for securing efficient and effective environmental governance, a rising tide of criticism warns of the potentially detrimental social–ecological consequences of nature commodification and ‘green neoliberalism’. These concerns are also expressed at international policy fora, where the market rhetoric has met with political resistance from countries belonging to the ‘Bolivarian Alliance for the Peoples of Our America’ (ALBA). But despite this ideological opposition, some ALBA countries are increasingly integrating PES into their environmental policies. In this article we consider the reasons underlying this apparent contradiction and relate it to the notion of ‘epistemic circulation’. On the basis of a study on the evolution of PES-thinking in Nicaragua (an ALBA member) and a reassessment of the supposed ‘success’ of an influential pilot project, we shed light on the forces driving the adoption of particular PES modes and contextualise practical difficulties to endorsing more critical approaches to the tool. Instead of either ideologically rejecting PES as a neoliberal evil or embracing it uncritically as the new panacea, we argue that it is precisely through the socio-political processes surrounding environmental governance debates that the application of PES is shaped. In practice, it may either contribute to an imposed and dispossessing form of capitalism, or tend towards a more negotiated and socio-culturally embedded version of it. Only through its reconceptualisation based on political–cultural primacy rather than market-fetishism can PES achieve its true potential within a broader strategy towards improved environmental governance.  相似文献   
106.
This paper examines the importance of national-level institutional arrangements for promoting the EU’s Protected Geographic Indication scheme (PGI). Taking the example of Ireland, for which PGI designations remain comparatively low, it explores whether the approach to providing institutional supports to the PGI scheme is influenced by top-down technocratic governance structures that pertain to food safety and quality certification that encompass the broader operating environment for food production in Ireland. Although the regulation of food safety and quality certification are distinct remits to the administration of the PGI scheme, in the Irish context the same institutional bodies are involved in governance of both. Using a discourse analysis interpretative framework, this paper draws on interviews with Irish producer group members and institutional representatives to examine how governance of the PGI scheme reflects management perspectives and practices more in keeping with a regulatory environment for food safety and quality than with development of place-based food product links. It suggests that incentives to avail of the PGI scheme as a means of realising value-added for producers are not well established because they require the development of more subjective, context-dependent processes and practices linked to geographical place and place identity. These are not easily accommodated under current institutional arrangements that also incorporate food safety and quality remits because these are in turn strongly established through nationally and internationally recognised systems of regulation and benchmarking. The findings point to the benefits to be gained from a more layered governance structure for PGI; devolving operation of the scheme to relevant regional and local development organisations that possess the expertise and relevant local knowledge to (a) incentivise the formation of producer groups, and (b) prioritise mentoring and support for PGI concept development as a clearer reflection of bottom-up rural sustainability policy.  相似文献   
107.
Increasing the rate of climate technology transfer is a critical concern. The international community facilitates the development and deployment of climate technologies for the needs of the South in two primary ways: first, through the use of multilateral frameworks for technology transfer and, second, through in-country capacity building for research, development, and deployment in developing countries. However, scant attention is given to whether national-level frameworks in industrialized countries can support technology transfer. This issue may be of particular relevance to small and medium enterprises (SMEs) in developed countries, due to their relative lack of experience in international markets. The barriers that prevent SMEs from developing and exporting more technologies to the South are identified, by using Israel as a case study. Although Israel is an important global source of climate technology innovation, it currently does not engage much with the developing world. Four principle barriers to greater involvement of OECD SMEs in technology transfer for climate mitigation in developing countries are: (1) lack of knowledge of market needs in developing economies, (2) lack of financial mechanisms to support R&D, (3) lack of opportunities for partnership building, and (4) lack of support for demonstration sites in developing countries.  相似文献   
108.
Scientists’ ideas, beliefs, and discourses form the frames that shape their choices about which research to pursue, their approaches to collaboration and communicating results, and how they evaluate research outputs and outcomes. To achieve ocean sustainability, there are increasing calls for new levels of engagement and collaboration between scientists and policy-makers; scientists’ willingness to engage depends on their current and evolving frames. Here, I present results about how scientists involved in diverse fields of ocean research perceived their role as scientists working at or near the ocean science–policy interface and how this related to their perceptions regarding ocean research priorities. The survey of 2187 physical, ecological and social scientists from 94 countries showed that scientists held different perspectives about their appropriate level of engagement at the ocean science–policy interface and the relative primacy of science versus politics in formulating ocean policy. Six clusters of scientists varied in their frames; three clusters accounted for 94% of the sample. Of 67 research questions identified from 22 research prioritization and horizon scanning exercises, the top eight were shared among all three clusters, showing consistency in research priorities across scientists with different framings of their role at the science–policy interface. Five focused on the mechanisms and effects of global change on oceans, two focused on data collection and management for long-term ocean monitoring, and one focused on the links between biodiversity and ecological function at different scales. The results from this survey demonstrated that scientists’ framings of the role of ocean science at the science–policy interface can be quantified in surveys, that framing varies among scientists, and that research priorities vary according to the framings.  相似文献   
109.
The public's willingness to engage in mitigation actions has not received as much attention as the level of belief in Global Warming (GW), especially on the international stage. Research in Western nations indicates that people systematically misunderstand GW and the actions required for mitigation. Important factors that influence judgments about mitigation actions include personal experiences, beliefs, knowledge, values, and worldviews. We present results of an international survey (25 samples from 24 countries) measuring general intentions to act and willingness to engage in specific actions. Our analysis reveals that endorsement of specific actions is (a) lower than general endorsement of mitigation, (b) accompanied by higher intra-individual variance, and (c) more strongly related to personal experiences with GW. This pattern can be attributed to the compatibility between the proximal construal of specific actions and the nature of the personal experience. Lastly we provide recommendations on how these findings can be used to encourage mitigation action.  相似文献   
110.
农作物长势遥感监测业务化应用与研究进展   总被引:1,自引:0,他引:1  
农作物长势监测可为田间管理提供及时的决策支持信息和早期估产提供依据。为了更好地研究作物生长过程中不同遥感监测作物长势方法的适用性,从多光谱遥感数据、高光谱遥感数据和微波遥感数据的应用及遥感监测指标与模型模拟方面综述了国内外农作物长势遥感监测研究及业务化应用的最新进展,指出了未来拟重点加强的研究任务,包括高时空分辨率和高光谱分辨率遥感数据的业务化技术、多遥感反演参数协同监测作物长势技术研发、基于遥感信息与作物过程模型的集合预报技术研究、全球尺度作物长势监测业务运行系统研发。  相似文献   
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