Study On The Change Of Forest Carbon Storage And Landscape After Different Fire Restore Year

The Daxing'anling Mountain was the most important ecological barrier of China,it paly the important role in ecological balance and global carbon cycle.Fire was the most important natural disturbance of forest ecosystem,forest restoration course was the gradual change process.Meanwhile,forest carbon and landscape pattern was the indicator of forest ecosystem healthy and sustainable development.We take the Huzhong mountians as the study area,through field investigation,data collection and model simulaiton,allometric relationships and harvest method to reaearch the change of carbon storage and forest landscape.Moreover,we take potassium dichromate oxidation titration-spectrophotometric method calculate the soil organic carbon(SOC),and statistic the change of forest landscape by the LANDSTAT and APACK.The main conclusions were as follows:1.With the forst retoration,the carbon density increased gradually.The loss of forest carbon density from 8.01% to 41.04% at restoration from 1y to 13 year.With the restoration time icreased,the difference between burned area and unburned area approach closed gradually.The carbon density loss of shrub layer at 0.02Mg/ha((1.61%)after 16 year restoration,the shrub layer density of burned area cannot restore to the unburned area.The carbon density of herbaceous layer varies greatly,fire increased the carbon density about 57.54% and it research 7.2Mg/ha at first year,with the restoration of forest,carbon density have no obvious difference between the burned area and unbrned area after 13 years.2.We investigate organic carbon of different depths soil(0-10,10-20,20-30,30-50,>50cm)after different fire disturbance,result indicate that the SOC most concentrate on surface soil.Meanwhile,the SOC of surface soil(0-10cm)increased from 12.09(g/Kg)to 47.11(g/Kg).SOC have obvious difference among different soil layer(P<0.05),and SOC increased with forest restoration years gradually.Although we investigate the change of SOC after fire disturbance 13 years,the SOC cannot reaearch level before fire disturbance.3.We study the forest landscape under different simulation scenarios(succession,natural fire,fire suppression)by LANDIS model,rusult indicate that the area percent of larch forest under succession scenarios was higher than other simulation scenarios,and the area percent of white birch lower than other simulation scenarios.The degree of aggregation index of larch and white birch under fire suppression,and fire suppression decreased mean patch area of larch and white birch cohorts,so we can conclude that fire suppression decreased stability of the forest,and we suggest that forest manager should take fule reduction and prescribed fire to decrease the fire risk,abandon the long term fire suppression.