Structural characteristics of forest state iiia3 between two altitude levels in core zone in Xuan Nha nature reserve, Van Ho district, Son La province

This study was conducted to understand altitudinal changes in stand structure and tree species diversity in evergreen broadleaf forest in core zone in Xuan Nha Nature Reserve. Six plots (20 m x 40 m), distributing between < 1,000 and > 1,000 m above sea level were used for stem census. All stems with diameter at breast height (DBH) ≥ 6 cm were identified to species and measured for DBH and height.