Abstract: In this paper,principal components analysis(PCA)was used for fifty climatic stations in the distribution region of Pinus koraiensis forests in N.E.China.Five climatics factors were used to explain the relationship between the distribution of the Pinus koraiensis and climate.They were annual average temperature,annual average precipitation,annual average humidity,average temperature in January(the coldest month)and in July(the hottest month).

Key words: Cunninghamia lanceolata plantation, carbon cycle, vegetation removal, litter decomposition