The Study On Characteristcis Of Coarse Woody Debris Of Larix Gmelinii In The Great Hing'an Mountains

Coarse woody debris(CWD)played an important role in forest ecosystem energy flow,material circulation,and maintaining the integrity and stability of forest ecosystems.CWD could scientifically and effectively quantify its storage and CWD was of great significance to further understand the role and role of CWD in the biogeochemical cycle and global carbon cycle and carbon balance.Investigation and analysis on the surface coverage,storage,structural characteristics,distribution characteristics of rot grade and spatial distribution pattern CWD of Larix gmelinii and Betula platyphylla in Larix gmelinii forest in Huzhong National Nature Reserve.We reached the following conclusions:(1)In terms of surface coverage of CWD in Larix gmelinii forest.The surface coverage of Larix gmelinii CWD was significantly higher than that of Betula platyphylla CWD.The surface coverage of Larix gmelinii was 3.33%,and the surface coverage of Betula platyphylla was 0.07%.(2)In terms of CWD storage in Larix gmelinii forest,the CWD storage of Larix gmelinii was significantly higher than that of Betula platyphylla CWD.The storage capacity of CWD in Larix gmelinii forest was 79.91m3/hm2.The storage capacity of CWD of Larix g,melinii was 64.77 m3/hm2,and the storage of Betula platyphylla CWD was 15.14 m3/hm2.The storage capacity of snags and stumps CWD of Betula platyphylla was significantly lower than that of fallen wood of Betula platyphylla.The storage capacity of snags and stumps CWD of Larix gmelinii was significantly lower than that of fallen woods of Larix gmelinii.However,the storage capacity of Larix gmelinii snags and stumps and fallen woods CWD was significantly higher than that of Betula platyphylla.(3)Structural characteristics of CWD in Larix gmelinii forest,the number of CWD individuals in Larix gmelinii and Betula platyphylla ware normally distributed in all diameter distributions.Among them,CWD of Larix gmelinii was mainly DHB<20cm,accounting for 83.76%of the total number of Larix gmelinii.was mainly DHB<10cm,accounting for 83.51%of the total number of CWD in Betula platyphylla.(4)In the height or length of CWD in Larix gmelinii forest,the number of CWD individuals in Larix gmelinii and Betula platyphylla ware normally distributed in all diameter distributions.Among them,the peak number of the snags and stumps and fallen woods of Larix gmelinii appeared at a height or length of 8m.The peak number of Betula platyphylla and fallen woods appeared at a height or length of 3m.(5)Characteristics of CWD decay grades in Larix gmelinii forest,the number of CWD in different decaying grades of Larix gmelinii and Betula platyphylla ware normally distributed.When the decay level was grade 3,the number of CWD in Larix gmelinii and Betula plalyphylla fallen woods was the highest.The highest number of CWD in the Betula platyphylla stands,when the decay level was grade 3.(6)In the spatial pattern of CWD in Larix gmelinii forest,the spatial pattern of CWD in Larix gmelinii and Betula platyphylla changed from cluster distribution to random distribution due to different species,existing forms and decay grades...