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I.StduyAreaPUschRjdgeoftheSantaCatalinaMountains,CoronadONaionalForest,SoutheastArizona,wasselectedasastudyareafOrvegetationmopingandatestoftheroleOfGISinaidingrem0teIysenseddataclassificati0n.BeinganepitOmeoftheSantaCatalinaMountains,PUscllmdgeiscomprisedOf23O.65sqUarelQnoflandIocatedonthesouthwesternPOrti0noftheSantaCarelinaRangerDistrictOftheCoronadoNationalForest.ltprovidesasharPcontrastbebeenthenamralruggdnessOftheSantaCatalinaMountainsandtheCityOfTucson,Arizona,araPdl…  相似文献   

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Basic concepts of cultural historical geography have been applied to a variety of community issues in St. Paul, MN. Through the process a sense of place has been developed at several scales. This inclusive sense of place has provided a link among various factions and made possible several compromises in land use and economic development issues. Most of the work was done through undergraduate field seminars.  相似文献   

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广西弄岗不同演替阶段植被群落的小气候特征   总被引:6,自引:0,他引:6  
探讨了广西弄岗自然保护区不同演替阶段群落不同梯度的气温、湿度、土壤温度、光照强度的日变化特征,结果表明各演替群落的平均气温,最高温度,最低温度,气温上升和下降的速度随着群落演替的进展呈下降趋势,各群落的气温垂直变化一般随高度增加而增加;各演替阶段群落的土壤5cm处的温度变化呈不规则的单峰曲线;随着演替的进展,各群落的空气相对湿度增大,空气相对湿度的变幅随着演替的进展而变小;一般来说,随着高度的增加,各演替阶段的光照强度也增加.  相似文献   

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Integration in human geography is achieved through multidimensional research or by the study of a variety of aspects of a whole. Giddens's structuration theory provides a new theoretical framework for integrative study in human geography in its attempt to connect individuals and societies, context and composition, time and space. Integrative studies in geography have focused on space (regional geography), time (historical geography) and society (time-geography). Structurationist analysis in geography can put society, space, or society and space at its focus. Thrift's spatial structurationist theory may lead to a new theoretically-based regionalism. On the other hand, integration at one level or between several elements may entail disintegration, at another level or element respectively.  相似文献   

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The box-and-whisker diagram, described here, is a simple but effective device for portraying frequency distributions clearly, accurately, and fully. It is a useful means for providing legends and category divisions for choropleth maps, being capable of handling skewed distributions without suppressing the skewness. Maps are used to illustrate the utility of the method for examining different types of distributions and for making map comparisons to discover relationships among variables.  相似文献   

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The lands with water,in general,are consideredas wetlands.The wetlands are most complex andhighly productive but more vulnerable ecosystem inthe earth.The wetland systems directly support mil-lions of people and provide good and services to theworld.They …  相似文献   

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Most regional maps of soil productivity are based on the erroneous assumption that the soil series, the fundamental taxonomic unit, is also a homogeneous unit of productivity with consistent and predictable yields when compared with other series. This assumption may lead to significant errors in estimates of potential productivity, with profound implications for prime-land delimitation, tax assessment, zoning administration, and other policies that presently rely on published soil productivity ratings.  相似文献   

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How researchers describe groups living within or near the world's tropical rain forests has important implications for how and why these groups are targeted for assistance by conservation and development organizations. This article explores how data about market behavior can be used to assess one aspect of forest peoples’ livelihoods: their “dependence” on forest resources as a source of market income. With the intent of revealing the importance of methodology to how we describe forest peoples’ livelihoods, I draw from a multiyear survey of market activity among the Tawahka Sumu of Honduras and distinguish nested measures of the Tawahkas’ engagement in forest-product sale. Results indicate that whether or not the Tawahka —or any forest group — can be considered financially “dependent” on forest resources depends on the spatial and temporal scales at which data are aggregated. As a group, the Tawahka earned 18 percent of total market income from forest-product sale, but their group profile masked a high degree of heterogeneity at the village and household level. Similarly, multiyear data indicated that while group-level generalizations adhere from year to year, they belie considerable change in households’ market behavior across years. I discuss three ways in which the findings are relevant to the theory and practice of conservation and development in the humid tropics. I emphasize the importance of spatial scale in interventions, how market-oriented conservation schemes can benefit from a broader conceptualization of the economic context in which forest-product sale occurs, and how longitudinal analysis can reveal the dynamism of forest peoples’ livelihoods.  相似文献   

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