Community structural properties and species diversity in primary Pinus yunnanensis forest

Key words: 
• forest ecology /
• primary Pinus yunnanensis forest /
• secondary Pinus yunnanensis forest /
• community structure /
• species diversity /
• restoration ecology

Abstract: Because the natural Pinus yunnanensis forestswere devastated severely in 1960s and 1970s, todays P.yunnanensis forests are mainly secondary stands.The aimis to compare the difference of both forests to find the way renewing the secondary forests. In primary P. yunnanensis forest of Baimahe, in Yongren County, Yunnan Province, community properties and species diversity were investigated using the Raunkiaer system.Also, richness and evenness of species distribution were compared to secondary P. yunnanensis forests. Results showed that the primary forests were mostly pure P. yunnanensis, but with rich species and diverse structures in their understories.In the community investigated,phanerophytes represented the largestproportion(46.1%)followed by chamaephytes(25.9%), hemicryptophytes(14.0%), cryptophytes(13.3%), and therophytes(0.7%). This indicated that the environment of the primary P. yunnanensis forest was warm and humid during its growing seasons. The individual diameter atbreastheight and age of trees in the community followed a normal distribution,which indicated that the successional structure of the primary P. yunnanensis forests was relatively stable. For richness and evenness of species distribution in the primary forests, the Simpson index, Shannon-Wiener index,and Pielou evenness indices Jsw and Jsi were 4.6, 3.7, 3.9, and 4.6 times respectively more than these of secondary forests. This verified that primary P. yunnanensis forests had higher species diversity than secondary forests.[Ch, 2 fig. 2 tab. 15 ref.]