针对岩溶区水体破碎、植被与水体重叠的特点提出一种新型混合水体指数对该地区水资源管理与评估有着重要作用。以2017年普者黑的Landsat8 OLI影像数据为基础数据,选择不同流域水系类型,构建新型混合水体指数NEWI,与归一化水体指数(Norma...针对岩溶区水体破碎、植被与水体重叠的特点提出一种新型混合水体指数对该地区水资源管理与评估有着重要作用。以2017年普者黑的Landsat8 OLI影像数据为基础数据,选择不同流域水系类型,构建新型混合水体指数NEWI,与归一化水体指数(Normalized Difference Water Index,NDWI)和改进的归一化水体指数(Modified Normalized Difference Water Index,MNDWI)进行对比,分析各指数的水体信息提取的准确性和完整性。结果表明:新型水体指数NEWI的提取效果优于NDWI和MNDWI,特别是含有坑塘和水体植被的破碎湖泊区域,NEWI计算水体与阴影的区分度25.3%,大于NDWI(17.9%)和MNDWI(15.6%);水体与非水体的总体识别精度为88.83%,Kappa系数0.76,也大于NDWI(87.10%,Kappa系数0.74)和MNDWI(81.93%,Kappa系数0.64)。利用NEWI对遥感影像进行水体增强的方法,不仅能够很好地提取出开阔水域的水体信息,边缘清晰可靠;对于破碎水域,NEWI水体提取精度最高,并且相比基于复杂数学理论的分类提取过程,操作相对简单,易于推广,能够较好地提高岩溶破碎区的水系提取和水域实时监测的精度。展开更多
The social and economical condition,cultivated land resources and general situation of grain production of research area are introduced.According to relevant data of cultivated land of Kunming City in 2006,taking the ...The social and economical condition,cultivated land resources and general situation of grain production of research area are introduced.According to relevant data of cultivated land of Kunming City in 2006,taking the minimum per capita cultivated land and index model of cultivated land pressure,and combining with two conditions of per capita grain demand which are 300 kg and 400 kg,the comparative research method was used to calculate and analyze the minimum per capita cultivated land and index model of cultivated land pressure.The results show that when per capita grain demand-Gr is 300 kg,the per capita cultivated land in Kunming City has regional differences,reflects different regular patterns of spatial distribution,and presents obvious and typical radial distribution.Urban area of Kunming has the lowest point and be taken as the center,per capita cultivated land decreases progressively from suburban to the periphery;when per capita grain demand-Gr is 400 kg,under the same consumption level,cultivated land pressures of each county in Kunming City are different,and so are the driven factors;when per capita grain demand-Gr is 300 kg or 400 kg,the indexes of cultivated land pressure in Kunming are all greater than 1,cultivated land pressure is enormous,the indexes of cultivated land pressure of each county(district) have two conditions-greater than 1 and less than 2,and the reasons differ from one another.Combining with the spatial distribution characteristics of the cultivated land and food and the situation of industrial development,the countermeasures and suggestions are put forwarded to make full use of back-up cultivated land,to plan the distribution of industrial structure in each county(district) of Kunming City as a whole,to dispose cultivated land resources reasonably and so on.展开更多
文摘针对岩溶区水体破碎、植被与水体重叠的特点提出一种新型混合水体指数对该地区水资源管理与评估有着重要作用。以2017年普者黑的Landsat8 OLI影像数据为基础数据,选择不同流域水系类型,构建新型混合水体指数NEWI,与归一化水体指数(Normalized Difference Water Index,NDWI)和改进的归一化水体指数(Modified Normalized Difference Water Index,MNDWI)进行对比,分析各指数的水体信息提取的准确性和完整性。结果表明:新型水体指数NEWI的提取效果优于NDWI和MNDWI,特别是含有坑塘和水体植被的破碎湖泊区域,NEWI计算水体与阴影的区分度25.3%,大于NDWI(17.9%)和MNDWI(15.6%);水体与非水体的总体识别精度为88.83%,Kappa系数0.76,也大于NDWI(87.10%,Kappa系数0.74)和MNDWI(81.93%,Kappa系数0.64)。利用NEWI对遥感影像进行水体增强的方法,不仅能够很好地提取出开阔水域的水体信息,边缘清晰可靠;对于破碎水域,NEWI水体提取精度最高,并且相比基于复杂数学理论的分类提取过程,操作相对简单,易于推广,能够较好地提高岩溶破碎区的水系提取和水域实时监测的精度。
基金Supported by Project of Social and Scientific Foundation of China(09XJY020)Project of Social and Scientific Foundation of Yunnan Province(HZ2009021)
文摘The social and economical condition,cultivated land resources and general situation of grain production of research area are introduced.According to relevant data of cultivated land of Kunming City in 2006,taking the minimum per capita cultivated land and index model of cultivated land pressure,and combining with two conditions of per capita grain demand which are 300 kg and 400 kg,the comparative research method was used to calculate and analyze the minimum per capita cultivated land and index model of cultivated land pressure.The results show that when per capita grain demand-Gr is 300 kg,the per capita cultivated land in Kunming City has regional differences,reflects different regular patterns of spatial distribution,and presents obvious and typical radial distribution.Urban area of Kunming has the lowest point and be taken as the center,per capita cultivated land decreases progressively from suburban to the periphery;when per capita grain demand-Gr is 400 kg,under the same consumption level,cultivated land pressures of each county in Kunming City are different,and so are the driven factors;when per capita grain demand-Gr is 300 kg or 400 kg,the indexes of cultivated land pressure in Kunming are all greater than 1,cultivated land pressure is enormous,the indexes of cultivated land pressure of each county(district) have two conditions-greater than 1 and less than 2,and the reasons differ from one another.Combining with the spatial distribution characteristics of the cultivated land and food and the situation of industrial development,the countermeasures and suggestions are put forwarded to make full use of back-up cultivated land,to plan the distribution of industrial structure in each county(district) of Kunming City as a whole,to dispose cultivated land resources reasonably and so on.
