Abstract:

The ground fixed sample plot is a basic sampling unit for forest resource monitoring in a large regional scale.The prediction accuracy of ground fixed sample will directly affect the accuracy of the overall regional monitoring results.Based on the sample type,spatial arrangement and size of the sample plot,random sampling method was adopted in a 1 hm² area plot to verify the optimal sample type of forest resources monitoring in different types of stands by sampling accuracy.The results showed that: 1) The optimal plot area scales for stock monitoring in different stand types were different.When laying ground fixed plots,the plot area and spacing should be determined according to the origin and age group of the stand.2) Under the condition that the sample area was the same,the sampling monitoring accuracy of the single round sample was slightly higher than that of the single square sample,the accumulation sampling monitoring accuracy of the cluster sample was obviously higher than that of the single cluster sample,and the sampling monitoring accuracy of the four-point round cluster sample was slightly higher than that of the square cluster sample.

Key words: forest resource monitoring, fixed ground plots, sampling accuracy, cluster plots