基于3阶段抽样方法的森林面积估测——以北京市延庆县为例

Estimating Forest Area with Three-stage Sampling——Taking Yanqing County of Beijing as An Example

为了优化我国的森林资源监测体系,以北京市延庆县为估测对象,利用美国森林资源清查方法(3阶抽样方法),在部分改进的基础上,通过设置正六边形抽样框架及群团样地,估测延庆县的森林面积。结果表明:估算出北京市延庆县的森林总面积为1 202.739 km^2,与延庆县政府报告的森林总面积对比,总体精度达到94.22%。分层随机抽样和分层双重抽样下的估计精度分别为99.96%和99.94%,这种面积估测方法具有较好的总体精度和稳定性。

We adopted the national forest inventory system of the USA （three-stage sampling） to optimize the national forest in- ventory system of China in Yanqing County of Beijing. According to some parts of the improvement, layout hexagonal sam- pling framework and circle sample area in Yanqing County of Beijing were developed. The total forest area of Yanqing County was 1 202.739 km^2. Compared with the reported forest area, the overall accuracy was 94.22%. The prediction accuracies were 99.96% and 99.94% by using stratified sampling and stratified double sampling, respectively.