Abstract:The study on fall and decomposition of Pinus korainsis needle is deficient in Changbai Mountain forest ecosystem. This article fills the need through investigations and experiments. The results show that Pinus korainsis needle usually lives for 3~4 years, and the longest is 6 years. The longevity has close relation with light. Needle decomposes faster in shady place where light is lack. After the needle falls, its decomposition becomes faster. Dry weight remains 16.6% after four year decomposition ...