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11.
结合临沂市几年来开展集体建设用地使用权流转的实践和探索,对开展集体建设用地使用权流转的背景、概念及范围进行了论述。认为在计划经济条件下形成的农民集体所有建设用地使用权不能流转的制度已与当前农村经济,特别是小城镇的建设发展严重不适应,允许集体建设用地使用权流转已势在必行。开展集体建设用地使用权流转对保护土地所有者和失地农民的权益,推动小城镇建设健康发展,规范土地市场具有重要意义。 相似文献
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Deborah F. Shmueli 《Geoforum》2008,39(6):2048-2061
When applied to environmental concerns, framing offers a rigorous conceptual and analytic approach with potentially practical significance for dealing with complex issues relevant to geography. The purpose of this article is to introduce framing concepts, typology and modes of analysis to address issues which geographers commonly treat: disputes over land ownership and uses, competition for water resources, cultural clashes over control of territory and resources and the impact of spatial patterns and structures when siting noxious sites. Framing analysis is applied to three cases of environmental conflict in Israel and, more generally, for understanding conflicts revolving around the management of human habitats in relation to the physical environment. 相似文献
15.
Models of natural and human dynamics in forest landscapes: Cross-site and cross-cultural synthesis 总被引:1,自引:0,他引:1
Miguel F. Acevedo J. Baird Callicott Donald Lyons Judith Rosales Magdiel Ablan Giorgio Tonella Emilio Vilanova 《Geoforum》2008,39(2):846-866
We synthesize the study of coupled natural and human systems across sites and cultures through a process of simplification and abstraction based on multiple dimensions of human-nature connectedness: satisfaction of basic needs, psycho-cultural connectedness and regulation of use of natural resources. We thus provide both a place-based and general understanding of value-driven anthropogenic environmental change and response. Two questions guide this research: what are the crucial stakeholder values that drive land use decisions and thus land cover change? And how can knowledge of these values be used to make decisions and policies that sustain both the human and natural systems in a place? To explore these questions we build simulation models of four study sites, two in the State of Texas, United States, and two in Venezuela. All include protected areas, though they differ in the specifics of vegetation and land use. In the Texas sites, relatively affluent individuals are legally converting forests to residential, commercial, and industrial uses, while in Venezuela landless settlers are extra-legally converting forests for purposes of subsistence agriculture. Contemporary modeling techniques now facilitate simulations of stakeholder and ecosystem dynamics revealing emergent patterns. Such coupled human and natural systems are currently recognized as a form of biocomplexity. Our modeling framework is flexible enough to allow adaptation to each of the study sites, capturing the essential features of the respective natural and anthropogenic land use changes and stakeholder reactions. The interactions between human stakeholders are simulated using multi-agent models that act on forest landscape models, and receive feedback of the effects of these actions on ecological habitats and hydrological response. The multi-agent models employ a formal logic-based method for the Venezuelan sites and a decision analysis approach using multi-attribute utility functions for the Texas sites, differing more in style and emphasis than in substance. Our natural-systems models are generic and can be tailored according to site-specific conditions. Similar models of tree growth and patch transitions are used for all the study sites and the differing responses to environmental variables are specified for each local species and terrain conditions. 相似文献
16.
This article describes a unique flood hazard, produced by the dramatic expansion of wetlands in Nelson County, located within
the North American Prairie Pothole Region of North Dakota, USA. There has been an unprecedented increase in the number, average
size, and permanence of prairie wetlands, and a significant increase in the size of a closed lake (Stump Lake) due to a decade-long
wet spell that began in 1993 following a prolonged drying trend. Base-line land cover information from the 1992 USGS National
Land Cover Characterization dataset, and a Landsat TM scene acquired 9 July 2001 are used to assess the growth of the closed
lake and wetland pond surface areas, and to analyze the type and area of various land cover classes inundated between 1992
and 2001. The open water profile in Nelson County changed from one marked by relatively comparable coverage of closed lake
and wetland pond areas in 1992, to one in which wetland open water accounted for the vast majority of total open water in
2001. The bulk of the wetland pond area expansion occurred by displacing existing wetland vegetation and agricultural cropland.
Producers responded to the flood hazard by filing Federal Crop Insurance Corporation (FCIC) claims and enrolling cropland
in the Conservation Reserve Program (CRP), a federal land retirement program. Land taken out of agricultural production has
had an enormous impact upon the agricultural sector that forms the economic base of the rural economy. In 2001 the land taken
out of production due to CRP enrollment and preventive planting claims represented nearly 42% of Nelson County’s 205.2 K ha
base agricultural land. The patterns obtained from this detailed study of Nelson County are likely to be the representative
of the more publicized flood disaster occurring within the Devils Lake Basin of North Dakota. 相似文献
17.
通过对天津市内主要河流上的4座具有代表性的闸涵进行详细的计算分析,得出闸涵水利工程维护费用中约19%属于地面沉降引起的损失,并将此比重推广到全市的闸涵工程,最后计算得出地面沉降造成的损失约为3.45亿元。 相似文献
18.
Farn Parungo Clarence Nagamoto Cecilia M. I. R. Girz Jeff Torgerson Zhou Mingyu 《海洋学报(英文版)》1995,14(2):201-207
ObservationofcloudsandsolarradiationoverthePacificOceanasrelationtoglobalclimate¥FarnParungo;ClarenceNagamoto;CeciliaM.I.R.Gi... 相似文献
19.
The VOF method and the k–ε model, combined with the equation of state of air at constant temperature, have been used to calculate the total horizontal wave force caused by monochromatic waves acting on a perforated caisson with a top cover. From comparison of various parameters, such as the total horizontal force, the pressure difference on the front wall, the pressure on the back wall and the pressure on the top cover, between the numerical results and test data, it can be seen that the numerical results agree well with the test data. It is concluded that the method described in this paper can be utilized to calculate wave forces acting on perforated caissons with a top cover in the case of nonovertopping, nonbreaking waves. A simplified method to calculate the total horizontal force has been developed, based on test data, using a least-squares method. A comparison between the numerical results and the values calculated from the simplified equations shows good agreement. Therefore the simplified equations can be used in engineering applications to evaluate the total horizontal force on a perforated caisson with a top cover. 相似文献