Abstract:

Based on the second class survey data of forest resources in Simao District of Pu'er City,taking forest origin,land type,age group and dominant tree species as stratified variables,the forest biomass was estimated by stratified sampling with 95%,90% and 85% sampling design accuracy under 95% reliability.The results show that:1) stratified sampling has obvious advantages of small sample size and high sampling accuracy.In Simao District of Pu'er City,the efficiency of stratified sampling based on dominant tree species is about 52% higher than that of systematic sampling with 85% design accuracy;2) stratified sampling based on single variable has significant advantages for dominant tree species.According to the design accuracy of 85%,the actual sampling accuracy can reach 87.82% under the premise of 44 samples.

Key words: forest biomass, stratified sampling, stand origin, forestland types, age group, dominant tree species, sampling accuracy