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Accuracy of Stream Habitat Interpolations Across Spatial Scales 被引量:1
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作者 Kenneth R. Sheehan Stuart A. Welsh 《Journal of Geographic Information System》 2013年第6期602-612,共11页
Stream habitat data are often collected across spatial scales because relationships among habitat, species occurrence, and management plans are linked at multiple spatial scales. Unfortunately, scale is often a factor... Stream habitat data are often collected across spatial scales because relationships among habitat, species occurrence, and management plans are linked at multiple spatial scales. Unfortunately, scale is often a factor limiting insight gained from spatial analysis of stream habitat data. Considerable cost is often expended to collect data at several spatial scales to provide accurate evaluation of spatial relationships in streams. To address utility of single scale set of stream habitat data used at varying scales, we examined the influence that data scaling had on accuracy of natural neighbor predictions of depth, flow, and benthic substrate. To achieve this goal, we measured two streams at gridded resolution of 0.33 × 0.33 meter cell size over a combined area of 934 m2 to create a baseline for natural neighbor interpolated maps at 12 incremental scales ranging from a raster cell size of 0.11 m2 to 16 m2. Analysis of predictive maps showed a logarithmic linear decay pattern in RMSE values in interpolation accuracy for variables as resolution of data used to interpolate study areas became coarser. Proportional accuracy of interpolated models (r2) decreased, but it was maintained up to 78% as interpolation scale moved from 0.11 m2 to 16 m2. Results indicated that accuracy retention was suitable for assessment and management purposes at various scales different from the data collection scale. Our study is relevant to spatial modeling, fish habitat assessment, and stream habitat management because it highlights the potential of using a single dataset to fulfill analysis needs rather than investing considerable cost to develop several scaled 展开更多
关键词 Natural NEIGHBOR Interpolation RESIDUALS Ordinary Least SQUARES STREAM Modeling HABITAT BENTHIC Substrate
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水资源压力的地理空间指示器:在非洲的应用
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作者 Charles J.Vrsmarty Ellen M.Douglas +2 位作者 Pamela A.Green Carmen Revenga 王纲胜 《AMBIO-人类环境杂志》 2005年第3期226-232,251,共8页
本研究说明了如何将全球已有的地球系统数据集用于世界上信息缺乏的地区进行水资源评价。8km分辨率的地理空间分析表明:64%的非洲人口所依赖的水资源是有限的和非常不稳定的。在那些有河流的地方,河流廊道水流对于增加当地径流、减少气... 本研究说明了如何将全球已有的地球系统数据集用于世界上信息缺乏的地区进行水资源评价。8km分辨率的地理空间分析表明:64%的非洲人口所依赖的水资源是有限的和非常不稳定的。在那些有河流的地方,河流廊道水流对于增加当地径流、减少气候波动的影响以及改善淡水获取条件都是非常关键的。农田在非洲最干旱的地区有很大比例,其中39%的灌溉无法持续。25%的人口面临着严重的水资源长期过度使用和水资源压力,另外13%的人口中每代人都会经历一次干旱造成的水资源压力。令人感到矛盾的是,对于绝大多数非洲人来说,水资源压力程度仍然很低,反映了较差的水资源基础设施与服务,以及较低的水资源利用水平。用水的适度增长可以降低对经济发展的制约,减少污染,以及降低对人类健康的挑战。开发一种明确的地理空间指示器,该指示器能综合集成生物地球物理、社会经济和工程设计等方面的信息,这将成为未来全球水资源评价中一个重要的步骤。 展开更多
关键词 水资源评价 地理空间 指示器 非洲 压力 应用 河流廊道 水资源利用 地球系统
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