Organic Carbon Activity and Reserve Characteristics of Soil of Root Layer in the Ecotone Between Minjiang Dry Valley and Montane Forest

It is comprehensively understood that soil animals,soil microorganism and soil enzyme mainly lived in the root layer soil ranges from several centimeters in surface to thirty centimeters depth in soil profile.To conclude,organic carbon activity and reserve characteristic in this layer are more sensitive to plant species change,soil quality change and global climate change.In this case,The ecotone between Minjiang dry valley and subalpine forest(EDM) and its adjacent ecosystem was taken into consideration,and organic carbon activity(i.e.readily oxidizable carbon(ROC),soil micro-biomass carbon(SMC)) and its reserve characteristics(i.e.soil organic carbon density(SOCD),soil organic carbon reserve(SOCR) of soil in root layer were measured.The results mainly indicated that ROC and SMC of soil of root layer in the core area of ecotone were in medium level,SF was highest in the elevation gradient.Moreover,the stability of soil in root layer in EDM was usually higher than other sits.SCOD of different depth in soil of root layer ranged from(0.14±0.007) kgC/m2 to(101.16±0.301) kgC/m2,SOCR ranged from(30.2±1.51) kg to(21850.6±65.02) kg.The soil organic activity of root layer of ecotone was higher than dry valley.It means that the ecotone might apply favorable carbon environment to plant growth in mountain altitudinal belts spectra.Although the natural vegetation area of EDM was less than dry valley and subalpine forest,the soil organic carbon density and organic carbon abundance index were better than dry valley.Inside ecotone,the plant community that taking Quercus semecarpifolia as dominant species had more strength capability of carbon reserve.It could be seen that Quercus semecarpifolia is the important reproducing tree species in vegetation modify project and other ecological engineering.