Study On Organic Carbon Density Of Forest Ecosystem In Jinggangshan

Forest as the most important part in terrestrial ecosystems, is the largest carbon storehouse in terrestrial ecosystems, it has play an irreplaceable part in regulating the balance of global carbon, slowing down the rate of concentration of CO2 and other greenhouse gases and regulating the global climate change. Therefore, studying carbon cycle and carbon collection in forest ecosystem has become the focus of the study on global climate change. In this paper, we take the major forest types in Jinggangshan nature as the research object, we compared carbon densities of five dominant forests in Jinggang Mountain from vegetation including arbor and understory vegetation, litter and soil layers, and we analysis of relevant aspects on carbon density and its influencing factors.The main conclusions are as follows:(1)The total carbon densities of forests descended from evergreen broadleaved forest>mixed needles and broadleaf forest> Cunninghamia lanceolata plantation, deciduous broadleaved forest to bamboo forest. The soil organic carbon densities of the five forests averaged 22.453 kg/m2, contributing 77.3% to the total carbon densities of forests. There was little variation among soil organic carbon densities of the five forests.Large variation was found among the vegetation carbon densities of five forests.The vegetation carbon densities had largest value in mixed needles and broadleaf forest(12.039 kg/m2) and smallest value in deciduous broadleaved forest (1.322 kg/m2), and the former was 9.1 times of the latter. The arbor carbon densities of forests descended from mixed needles and broadleaf forest(11.877 kg/m2)>evergreen broadleaved forest, C. lanceolata plantation, bamboo forest to deciduous broadleaved forest(1.156 kg/m2).Shrub carbon densities varied among five forests and were highest (0.153 kg/m2) and smallest (0.027 kg/m2) in evergreen broadleaved forest and deciduous broadleaved forest, respectively. There was little variation among herb carbon densities of the five forests ranging from 0.074 kg/m2 (C. lanceolata plantation) to 0.108 kg/m2 (bamboo forest).Litter carbon density was the smallest in all layers. There was little variation among herb carbon densities of the five forests ranging from 0.064 to 0.084 kg/m2.(2) Through set up the shrub biomass models to estimate the biomass of shrubs in Jinggangshan, this method had high precision and easy to use.it. When we analyzed the shrub biomass models we can find that model factors mainly dominated by diameter and height. Choose an measurement factors which are objective and easy to operate is the key to build model.(3) The result of correlation about the density of evergreen broad-leaved forest and Cunninghamia lanceolata plantation and NDVI, LAI and volume was that carbon density of all layers in evergreen broad-leaved forest and Cunninghamia lanceolata plantation were not saliency to NDVI; Arbor and vegetation layer's carbon density had a high correlation with volume(R2>0.97), but not very good with LAI. When we simulated the total carbon density, the values (R2) were not reach a significant level, except evergreen broad-leaved forest and volume(R2>0.7).The result of correlation about the density of total carbon density of the two forest types with volume and LAI was not very good except evergreen broad-leaved forest's overall carbon density had a good correlation with volume.(4) The carbon density of evergreen broad-leaved forest and Cunninghamia lanceolata plantation had a good correlation with annual average temperature and annual precipitation. The carbon density of evergreen broad-leaved forest had positive correlation with annual average temperature and negative correlation with annual precipitation. The carbon density of Cunninghamia lanceolata plantation had positive correlation with annual precipitation and negative correlation with annual average temperature.Environmental factors such as temperature and precipitation are interrelated and interact on each other which will bring far-reaching to plant growth and carbon storage.As the complexity of forest ecosystems of their own, biomass estimation models have non-uniform standards, this may give reduced the comparability of research findings.Therefore, we must increase more new technologies and new methods to carbon storage research than before and according to different regions to build biomass estimation models to improve accuracy and then improve the comparability of research findings.