The Characteristics Of Coarse Woody Debris And Its Influence On The Soil In Burned Mark Place Of Great Xing’an Mountains

Coarse woody debris are the important structural and functional elements in the forest, In the material and energy circulation of ecosystem has the effect that cannot replace. In order to understand the relevant features of coarse woody debris in different burned forest ecosystem of Great Xing’an Mountains, The result showed that:The Coarse woody debris of Great Xing’an Mountains consists of two kinds of tree species, Pinus sylvestris and larix. The storage of coarse woody debris in mild burning forest ecosystem was (10.89±0.66) t·hm-2 while the mean storage of FWD (Fine woody debris) was 0.42 t·hm-2, The storage of coarse woody debris in severe burning forest ecosystem was (5.37±0.44) t·hm-2 while the mean storage of FWD (Fine woody debris) was 0.17t ·hm-2. Among snags, logs, and stumps, logs accounted the biggest percentage in different burned forest ecosystem. The Coarse woody debris of Ⅰ is the most in mild burning forest ecosystem while the Coarse woody debris of Ⅴ is the least. But we can not find the Coarse woody debris of I in severe burning forest ecosystem and the Difference between Ⅱ、Ⅲ、Ⅳ、Ⅴ were small.The water holding capacity and water holdup of coarse woody debris was increased with increasing levels of decay, In water soaking process, the water holding capacity (Q) of coarse woody debris increased with the addition of immersion time (t). The relationship between Q and t fitted Q= alnt + b. The relationship of water-holding capacity (Q’) and rot rating (x) could use Q’=ex2+fx+g to fit. With the increase of immersion time (t), the water absorption rate (Ⅴ) of coarse woody debris decreased, The relationship can use Ⅴ= ktn to fit. The water storage of coarse woody debris in mild burning forest ecosystem was (27.62±3.97) t·hm-2. The water storage of coarse woody debris in severe burning forest ecosystem was (16.95± 2.851) t·hm-2.The relationship of the soil Saturated water storage between different Decomposition level in mild burning forest ecosystem was Ⅲ> Ⅴ> Ⅳ> Ⅱ> Ⅰ, while severe burning forest ecosystem was Ⅴ> Ⅲ> Ⅳ> Ⅱ. The biggest is the Ⅴ while the minimum is the Ⅱ in all chemical indicators of soil. The different between Comparison of soil and the Ⅱ is small, but they all greater than the Ⅱ.From Ⅱ to Ⅴ were increased with the increase of decomposition level, On the whole with the increase of decomposition level of each nutrient element content showed a trend of "√".