A knowledge model was incorporated to establish gis - and gps - and model - based dsspf . the models used in dsspf included crop management knowledge model established in our laboratory , new model based on spatial variability analysis Dsspf所采用的模型是在解析本实验室已构建的作物管理知识模型的基础上,由部分适用精确农作技术的作物管理知识模型模块和基于空间差异分析的新模型整合而成的。
The result shows that not only spatial precipitation heterogeneity and spatial land use / cover variability but also spatial soil evaporation heterogeneity influences flood simulation . as remarked above , spatial variability is very crucial to hydrological modeling 计算结果表明不仅降水空间分布、模型参数对水文过程模拟的精度有很大的影响,而且土壤蒸发空间不均匀性对模拟洪水也有一定的影响。
Geo - statistics is the most available method to study spatial variability and spatial distribution of soil properties . previous studies were concentrated on spatial variability of soil properties and soil water - storage in flat , ignoring how terrain affects soil properties 以往的研究都集中于平地土壤特性的空间变异性研究,对坡面土壤特性研究较少,从而,忽略了地形对土壤特性空间变异性的影响。
23 compounds of polycyclic aromatic hydrocarbons ( pahs ) were measured and identified by gc - ms in surface sediments at 13 stations in jiaozhou bay of qingdao costal sea , shandong peninsular , china , to investigate the spatial variability of the anthropogenic pollutants and their sources 利用气相色谱-质谱方法( gc - ms )对青岛近海胶州湾13个站位的表层沉积物中23种多环芳烃( pahs )的含量分布及来源进行了讨论。
The theory and method of geostatistics are currently still one tide of researching spatial variability quantitatively both at home and abroad . but research about soil spatial variability still focus on soil physical characters , articles in soil chemical properties is rarely found 随着地理信息系统( gis )的广泛应用和地理学学科的发展,利用地统计学,结合gis技术来研究土壤性质空间变异已成为目前的土壤学的研究热点之一。
In order to derive this equation , one has to assume no spatial variability in k , f and n , to neglect the effect of capillary rise above the groundwater table , and to invoke the dupuit - forcheimer approximation , which states that the hydraulic head is independent of depth 图1潜水面的示意图为了利用dupuit - forcheimer假设推导出以上的方程,必须假设k , f以及n t在整个潜水面上的空间不变性,同时忽略潜水面上的水分的毛细运动
On the platform of digital basin derived from raster dem data , - a grid - based hydrological model and a subcatchment - based hydrological model were used to study the effects of spatial variability on runoff process on such aspects as precipitation , model parameters and soil evaporation 在构建的数字流域平台基础上,建立分别基于子流域离散和栅格离散的数字水文模型,从而分析研究降水、模型参数和土壤蒸发的空间不均匀性对模拟水文过程的影响。
The parameter in the xin ' anjiang model , imp , was extracted directly from above land use / cover data . another parameter , sm , in each subcachment and in each raster grid was obtained from the relation between sm and the ratio of forest land area to subcatchment area . thus , a semi - distributed hydrological model and a distributed hydrological model were established to analyze the effect of some parameters in xin ' anjiang on runoff process according to the spatial variability of land surface characteristics 将遥感技术获取的土地利用和地表覆盖一公里栅格信息与数字高程模型数据进行空间配准,然后通过构建林地面积比与新安江模型参数sm的关系间接确定各子流域及各栅格单元的的sm值,新安江模型参数imp由配准好的土地利用和地表覆盖信息直接提取,由此建立方案与方案,来分析受下垫面覆盖的空间不均匀性影响的模型部分参数是如何对模拟水文过程产生影响的。
Spatial variability occurs when a quantity that is measured at different spatial locations exhibits values that differ across the locations. Spatial variability can be assessed using spatial descriptive statistics such as the range.