Characteristics Of Carbon Storage In Evergreen Broad-leaved Forests In The South Of Anhui

Global carbon cycle is one of the core issues in global climate change research.The carbon cycling in forest ecosystem is the most important part of global carbon cycle.In this study,the evergreen broad-leaved forests in southern Anhui were chosen,their structure and biomass carbon storage were investigated.The main results are as follows.(1)The average diversity index and evenness index were 1.43 and 0.59,respectively.The mean richness was 10.5.The dominant tree species in those evergreen broad-leaved forest are Castanopsis eyrei,Castanopsis sclerophylla and Cyclobalanopsis glauca.The DBH frequency distribution appeared an inverted “J” type.The mean DBH of the sampling stands was 15.1 cm,the average tree height was 11.4 m.The mean stand density was 1440 stems/hm2.(2)The estimated biomass ranged from 86.52 to 412.82 t/hm2 for the sampling stands with the average of 183.43 t/hm2.The biomass carbon storage ranged from 38.66 t/hm2 to 198.15 t/hm2 with the average of 88.05 t/hm2.The dominant tree species contributed 84.63% of the total carbon storage.The biomass and its carbon storage differed with stand age.The biomass carbon storage showed an increasing trend with stand age.(3)The mean concentrations of soil organic carbon(SOC)ranged from 25.40 g/kg to 57.14 g/kg for the 0-10 cm soil layer.The related SOC density ranged from 14.92 t/hm2 to 60.23 t/hm2.In 10-20 cm soil depth,the SOC concentrations were between 13.48 g/kg(minimum)and 36.81 g/kg(maximum).The related SOC density ranged from 14.92 t/hm2 to 43.53 t/hm2.In 20-30 cm soil layer,the mean SOC concentrations ranged from 3.76 g/kg to 15.35 g/kg and the SOC density was from 4.63 t/hm2 to 20.43 t/hm2.The result from regression analysis indicated that the SOC concentration was negatively correlated to soil bulk density.Soil carbon concentration and their density differed with stand age.However,there was no significant relation between soil organic carbon density and stand age.(4)The correlation analysis showed that the stand biomass carbon storage was significantly correlated with tree diversity index(P < 0.05),while was not significantly related to evenness index.In addition,the stand biomass carbon density was significantly positively correlated with mean DBH and tree height(P < 0.05)with the regression coefficients of 0.66 and 0.62 respectively.Stand density and biomass carbon storage was significantly negatively correlated(P < 0.05)with regression coefficient –0.64.