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51.
《Marine Policy》2014
This Special Issue reflects work developed during and following the execution of the Science and Policy Integration for Coastal System Assessment project. Theoretical and practical outcomes of case studies have been of direct relevance to coastal management not only at local but also at a European scale. Papers included here consider the long term legacy of the project for academics and practitioners involved specifically in integrated coastal zone management. These align to two themes, the first focussing on the generic application of the Systems Approach Framework to coastal management and the second focussing on the specific application of the approach at case study sites. 相似文献
52.
1980年以来京津冀区域研究进展评论 总被引:1,自引:0,他引:1
1980年以来,因研究内容和空间治理重点不同,京津冀、京津唐、环渤海、大渤海等区域名称与区域范围多次变动。作为中国最早开展人文与经济地理学研究的对象区域,越来越受到经济贸易、生态环境、城乡规划等多学科关注。本文基于学术论文和专著、具有影响的科研项目,对1980年以来京津冀及相关区域研究进展进行了综述和评论。归纳起来,研究对象区域经历了“京津唐(塘)—大(环)渤海—京津冀”的变化过程。整体上可分为4个阶段:20世纪80年代面向京津唐地区,国土规划为主的经济地理学区域研究,研究规模有限;20世纪90年代拓展到大(环)渤海地区,面向东(北)亚区域经济一体化进程开展经济贸易科学与地理学交叉研究;21世纪前10年,回归京津冀区域,生态环境科学和城市规划科学大规模介入的融合研究;21世纪10年代京津冀协同发展的多学科区域综合研究。其间,中央政府在该区域开展的一系列重大规划,包括20世纪80年代京津唐国土规划和90年代环渤海经济协作区规划,21世纪前10年京津冀都市圈区域规划和21世纪10年代京津冀协同发展规划,与区域研究形成了良性互动关系,在显著增强空间规划和战略决策的科学性的同时,也有力地促进了人文与经济地理学科发展,推动了人和自然相互间强烈作用状态下区域复杂系统演化规律的研究进展。 相似文献
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54.
Vegetation changes can significantly affect catchment water balance. It is important to evaluate the effects of vegetation cover change on streamflow as changes in streamflow relate to water security. This study focuses on the use of statistical methods to determine responses in streamflow at seven paired catchments in Australia, New Zealand, and South Africa to vegetation change. The non‐parametric Mann–Kendall test and Pettitt's test were used to identify trends and change points in the annual streamflow records. Statistically significant trends in annual streamflow were detected for most of the treated catchments. It took between 3 and 10 years for a change in vegetation cover to result in significant change in annual streamflow. Presence of the change points in streamflow was associated with changes in the mean, variance, and distribution of annual streamflow. The streamflow in the deforestation catchments increased after the change points, whereas reduction in streamflow was observed in the afforestation catchments. The streamflow response is mainly affected by the climate and underlying vegetation change. Daily flow duration curves (FDCs) for the whole period and pre‐change and post‐change point periods also were analysed to investigate the changes in flow regime. Three types of vegetation change effects on the flow regime have been identified. The relative reductions in most percentile flows are constant in the afforestation catchments. The comparison of trend, change point, and FDC in the annual streamflow from the paired experiments reflects the important role of the vegetation change. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
55.
As adaptation has come to the forefront in climate change discourse, research, and policy, it is crucial to consider the effects of how we interpret the concept. This paper draws attention to the need for interpretations that foster policies and institutions with the breadth and flexibility to recognize and support a wide range of locally relevant adaptation strategies. Social scientists have argued that, in practice, the standard definition of adaptation tends to prioritize economic over other values and technical over social responses, draw attention away from underlying causes of vulnerability and from the broader context in which adaptive responses take place, and exclude discussions of inequality, justice, and transformation. In this paper, we discuss an alternate understanding of adaptation, which we label “living with climate change,” that emerged from an ethnographic study of how rural residents of the U.S. Southwest understand, respond to, and plan for weather and climate in their daily lives, and we consider how it might inform efforts to develop a more comprehensive definition. The discussion brings into focus several underlying features of this lay conception of adaptation, which are crucial for understanding how adaptation actually unfolds on the ground: an ontology based on nature–society mutuality; an epistemology based on situated knowledge; practice based on performatively adjusting human activities to a dynamic biophysical and social environment; and a placed-based system of values. We suggest that these features help point the way toward a more comprehensive understanding of climate change adaptation, and one more fully informed by the understanding that we are living in the Anthropocene. 相似文献
56.
Deep excavations particularly in deep deposits of soft clay can cause excessive ground movements and result in damage to adjacent buildings. Extensive plane strain finite element analyses considering the small strain effect have been carried out to examine the wall deflections for excavations in soft clay deposits supported by retaining walls and bracing. The excavation geometry, soil strength and stiffness properties, and the wall stiffness were varied to study the wall deflection behavior. Based on these results, a simple Polynomial Regression (PR) model was developed for estimating the maximum wall deflection. Wall deflections computed by this method compare favorably with a number of field and published records. 相似文献
57.
58.
Water harvesting has been widely applied in different social-ecological contexts, proving to be a valuable approach to sustainable intensification of agriculture. Global estimates of the potential of water harvesting are generally based on purely biophysical assessments and mostly neglect the socioeconomic dimension of agriculture. This neglect becomes a critical factor for the feasibility and effectiveness of policy and funding efforts to mainstream this practice. This study uses archetype analysis to systematically identify social-ecological regions worldwide based on >160 successful cases of local water harvesting implementation. We delineate six archetypal regions which capture the specific social-ecological conditions of the case studies. The archetypes cover 19% of current global croplands with hotspots in large portions of East Africa and Southeast Asia. We estimate that the adoption of water harvesting in these cropland areas can increase crop production up to 60–100% in Uganda, Burundi, Tanzania and India. The results of this study can complement conventional biophysical analysis on the potential of these practices and guide policy development at global and regional scales. The methodological approach can be also replicated at finer scales to guide the improvement of rainfed agricultural. 相似文献
59.
1 INTRODUCTION Ovarian development of female crustaceans is under the direct regulations of two neurohormones: gonad-inhibiting hormone (GIH) secreted by optic ganglia and gonad-stimulating hormone (GSH) se- creted by brain and thoracic ganglia (Fingerman… 相似文献
60.
《The Professional geographer》1982,34(3):352-379
Books reviewed in this article: Aerial Photography and Remote Sensing Aerial photography and image interpretation for Resource Management . DAVID P. PAINE . Analytical Models and Techniques Spatial Processes Models and Applications A. D. CLIFF AND J. K. ORD Quantitative and Statistical Approaches to Geography: A Practical Manual JOHN A. MATTHEWS . Cartography and Maps Map Data Processing . HERBERT FREEMAN AND GOFFREDO G. PIERONI , eds. Computer-assisted Cartography: Principles and Prospects, 1982 . MARK S. MONMONIER . Cultural Navajo Architecture: Forms, History, Distributions . STEPHEN C. JETT AND VIRGINIA E . SPENCER . Rational Landscapes and Humanistic Geography . EDWARD RELPH . Economic The Structure and Control of a State Economy . W. L. L'ESPERANCE . Economic Geography . JAMES O. WHEELER AND PETER O. MULLER . The Myth of the Family Farm: Agribusiness Dominance of U.S. Agriculture . INGOLF VOCELER . Libya: The Experience of Oil . J. A. ALLEN . Geography of Public Finance, Welfare Under Fiscal Federalism and local Government Finance . ROBERT BENNETT . Environmental Management, Resources, and Systems Mountains and Man . LARRY W. PRICE . Environmental Geology . DONALD R. COATES . An Introduction to Environmental Systems . G. H. DURY . The Environment: Chinese and American Views . Edited by LAURENCE J. C. MA AND ALLEN G. NOBLE . Land Use in America . RICHARD H. JACKSON . Medical Conceptual and Methodological Issues in Medical Geography . MELINDA S. MEADE (ed.). Philosophy and Geographic Thought Birds in Egg/Eggs in Bird . GUNNAR OLSSON . PhysicaI Climatology: Selected Applications . J. E. OLIVER . Geomorphological Techniques . ANDREW GOUDIE (ed.). Political Politics, Geography and Behaviour . RICHARD MUIR AND RONAN PADDISON . The State of the World Atlas . MICHAEL KIDRON AND RONALD SECAL . Population The Population of the South . DUDLEY L. POSTON , JR . AND ROBERT H. WELLER , eds. Regional Latin America: Economic Development and Regional Differentiation . ARTHUR MORRIS . Developing the Amazon . EMILIO F. MORAN . Western Europe: A Systematic Human Geography . BRIAN W. ILBERY . Settlement Systems in Sparsely Settled Regions: The United States and Australia . RICHARD E. LONSDALEAND JOHN H. HOLMES , eds. African Perspectives: The Economic Geography of Nine African States . HARM DE BUJ AND ESMOND MARTIN , eds. Rural Nonmetropolitan America in Transition . AMOS H. HAWLEY AND SARA MILLS MAZIE , eds. Social Crime and Environment . R. NORMAN DAVIDSON . The Ghetto: Readings with Interpretations . JOE T. DARDEN , ed. Urban Urban Problems and Planning in the Developed World . MICHAEL PACIONE (ed.) Problems and Planning in Third World Cities . Edited by MICHAEL PACIONE . The City in West Europe . D. BURTENSHAW , M. BATEMAN , AND C. J. ASHWORTH . 相似文献