Estimation Of Carbon Storage In Typical Subtropical Evergreen Broad-leaved Forests In Jiangxi Province Based On Remote Sensing Image

The carbon resources of subtropical evergreen broad-leaved forest in Jiangxi Province is an important component of forest carbon pool in Jiangxi Province and occupy an important proportion in Jiangxi and national forest carbon stocks.In this paper,three typical subtropical evergreen broad-leaved forests(Schima superba,Cyclobalanopsis glauca forest and Castanopsis sclerophylla forest)were selected as the research object.The field investigation and remote sensing estimation were used in investigating the carbon storage correlation factors of the species in Jiulian Mountain,Jinggangshan and Dagangshan.The carbon storage and the carbon density of the vegetation and soil in the standard plot were calculated.A vegetation index remote sensing estimation model was established to estimate the vegetation and soil carbon storage,carbon density of subtropical evergreen broad-leaved forest in Jiangxi Province.Based on the remote sensing image data of Jiangxi Province from 1985 to 2015,the temporal variation of vegetation and soil carbon storage and carbon density of subtropical evergreen broad-leaved forest in Jiangxi Province over the past 30 years were analyzed.On the basis of this,the trend of vegetation and soil carbon storage in the next 20 years was forecasted.It also analyzed forest carbon storage and carbon density of the subtropical evergreen broad-leaved forest in Jiangxi Province.The results are as follows:(1)Vegetation plots in different organs had different carbon content,the tree layer showed that leaf(50.14%)>branch(48.50%)>stem(48.20%)> root(47.55%);the shrub layer was leaf(48.23%)>branch(47.72%)> root(47.12%),the herb layer was the root(42.87%)> leaf(41.98%),the carbon content of the litter was 42.36%.(2)In the soil layer of the standard plot,the soil bulk density increased with the increase of the depth(0-100cm),and the soil organic carbon content decreased.Soil bulk density at different depths were 1.2128 g/cm3(0-10cm),1.2154 g/cm3(10-20 cm),1.2507 g/cm3(20-30cm),1.2788 g/cm3(30-50cm),1.2938 g/cm3(50-100 cm).The contents of organic carbon in different soil layers were 3.5%(0-10cm),2.47%(10-20cm),1.9%(20-30cm),1.63%(30-50cm),1.14%(50-100cm).(3)The vegetation reserves of the standard plots were from 1.160 t to 22.762 t,with a mean of 7.591 t,the mean value of carbon storage in each vegetation layer was 7.106 t of tree layer,0.212 t of shrub layer,0.093 t of herb layer and 0.180 t of litter,The average carbon density of each vegetation layer was 78.96 t/hm2 of trees,2.34 t/hm2 of shrub layer,1.04 t/hm2 of herb layer,1.97 t/hm2 of litter layer.(4)The soil carbon storage of the standard plots was from 7.08 t to 34.22 t,the mean value was 17.18 t,and the mean values of 0-10 cm,10-20 cm,20-30 cm,30-50 cm,50-100 cm of each soil layer were 40.19 t / hm2,29.78 t / hm2,23.29 t / hm2,40.06 t / hm2,57.53 t / hm2.The soil carbon density was from 78.61 t / hm2 to 380.25 t / hm2,the mean value was 190.84 t / hm2,and the mean values of 0-10 cm,10-20 cm,20-30 cm,30-50 cm,50-100 cm of each soil layer were 40.19 t / hm2,29.78 t / hm2,23.29 t / hm2,40.06 t / hm2,57.53 t / hm2.(5)Through model construction and analysis,NDVI model of vegetation and soil carbon storage is superior to RVI model.The NDVI model was used in estimating the carbon storage and soil carbon storage and carbon density of subtropical evergreen broad-leaved forest in Jiangxi Province from 1985 to 2015.During the period from 1985 to 2015,the vegetation carbon storage increased from 0.1254 GtC to 0.2092 GtC,and the vegetation carbon density increased from 61.07 t/hm2 to 76.31 t/hm2.The soil carbon storage increased from 0.3820 GtC to 0.5474 GtC,the soil carbon density increased from 185.99 t/hm2 to 199.69 t/hm2,and the vegetation carbon storage and soil carbon storage of subtropical evergreen broad-leaved forest in Jiangxi Province were predicted in the next 20 years.The vegetation carbon storage and soil carbon storage showed an increasing trend.(6)Finally,the factors which affected the vegetation and soil carbon storage of subtropical evergreen broad-leaved forest in geography,meteorology and biological in Jiangxi Province were analyzed.Vegetation carbon density and longitude were significantly correlated,Soil carbon density and were correlated with latitude and slope;Vegetation carbon density was consistent with the trend of temperature,rainfall and sunshine duration.The trend of soil carbon density was consistent with that of temperature,which was consistent with the change of rainfall and sunshine duration.With the increase of age,the accumulation of vegetation carbon storage is increasing continuously.The carbon storage of tree layer has the greatest influence on vegetation carbon storage.