Study On Carbon Storage And Species Diversity In Forest Ecosystems With Different Years Of Restory

The carbon sequestration of forest can reduce atmospheric CO2 concentration.Scientific and rational selection of cutting years can increase forest carbon sequestration and achieve forest structural adjustment.At present,the impact of selective cutting on the actual carbon storage in forests has not been studied.It is not clear what kind of deviation exists between the estimated and the measured forest carbon storage.And the DBH,which reflects the growth status of trees,There is no understanding of what mechanism between the DBH and forest carbon storage.Here,we selected seven different recovery years(100a,60a,50a,40a,30a,20a,and 10a)and 803 species in temperate coniferous and broad-leaved mixed forests to measure the carbon contents of leaves,branches,stems,and roots of the tree and the shrub.The biomass,carbon content,and distribution pattern of various components(tree layer,shrub layer,herb layer,soil layer)and organs of temperate mixed conifers and broad-leaved forests in different selection years were studied.We estimated and analyzed carbon storage and dynamic changes of forest ecosystems for different cutting years as well as the relationship between DBH and forest carbon storage.Furthennore we clearly defined the deviation between estimated and measured carbon storage.Our results show that:Biomass allocation in different organs of tree Layer and shrub layer during different recovery years of selective cutting were:trunk>branch>root>leaf,The longer the recovery time,the more biomass is accumulated in each organ;The years of selective cutting have a significant effect on vegetation while have no significant effect on soil carbon storage.A reasonable selection of cutting years can increase the carbon storage of forest vegetation and ecosystems;Estimates of carbon storage has errors in different carbon content parameter estimation methods,using a carbon content of 0.45 x biomass to estimate carbon storage of vegetation is 2.99%lower than the actual value,using a carbon content of 0.50× biomass to estimate carbon storage of vegetation is 8.41%higher than the actual value;There is a significant positive correlation between DBH and the carbon storage of vegetation and ecosystem;The carbon storage of selective cutting forest begins to exceed the original forest when the average diameter at breast height is 16.3cm.The parameter of DBH can be used as a reference to combine sustainable forest management with forest carbon sequestration.The longer the recovery time,the more species composition of forest community,the more complex the community structure,and the greater the species diversity index.When the recovery time reaches more than 60 years,the forest species diversity is almost close to the original forest.There is a positive correlation between species diversity index and carbon storage of forest ecosystem.Compared with other indexes,Shannon-Weiner and Simpson index have greater impact on carbon storage of ecosystem.