Carbon Stock And SOC Stability In Soils Of Typical Plantations In North China

Over the years, climate warming caused the global atmospheric CO2concentration has become a serious problem placed in front of the human. Forestecosystems, as the most widely distributed in nature, is one of the most importantterrestrial ecosystems, playing a key role in the global carbon cycle. Northeast ChinaTransect （NECT） is based on water as the main driving factors transect, which coversa large area of Northeast China forest vegetation, has an important significance forresearching. However, the soil organic carbon storage of forest vegetation and itsstability of the NECT different precipitation gradient is not clear. Order to explore thesoil organic carbon storage and stability of the plantation, selecte two kinds of typicalplantation （Larix and Pinus sylvestris） as the object of study, comparative analysis ofLarch and Pinus sylvestris plantations soil organic carbon storage（SOC）, microbialbiomass carbon（MBC） and soil easily oxidized organic carbon（Clab） content, whileanalysising the indicators change on the slope position and soil depth of the twoforest types. The results of this study show that:（1） The research results of soil organic carbon content and its stability on theLarch plantation show: the slope position is the key factor affecting soil organiccarbon content and its stability, and has an important role on soil physical andchemical properties. Slope position and soil layers have significantly interaction onSOC （P <0.05）, with soil deep, slope larch plantation soil organic carbon content hasthe most obvious change, from layer Ⅰ（0to5cm）39.71g·Kg^-1to layer Ⅳ （5to10cm）9.09g·Kg^-1; layer III （10to20cm） soil organic carbon content, depending on theslope position has the most obvious, the lower slope up to13.74g·Kg^-1, the middle ofthe slope minimum to10.62g·Kg^-1. Slope position and soil layers have significantlyinteraction on MBC and Clabis extremely significant （P <0.01）; the accumulation ofstrength of SOC in the deeply layers is increasing, Clabis layer by layer decreased.This indicated that the stability of soil organic carbon pools of the Larch plantationstrengthened with soil depth. （2） The research results of soil organic carbon content and its stability on Pinussylvestris （the Qing ditch Ecological Station）, show: soil organic carbon contentdecreases with the increase of soil depth, layer I （0⁵cm） is6.77g·Kg^-1to layer IV（20to30cm）3.51g·Kg^-1; MBC distribution pattern is the same with SOC. Clabcontenttrends is opposite with SOC, significantly increased with the increase of soil depth.（3） The research results of soil organic carbon content and its stability on twotypical plantations （NECT, rainfall is the driving factor） show: SOC, carbon storage,MBC and Claball have a significant positive correlation with soil water content.Under the differences of rainfall and soil moisture, SOC, carbon storage, MBC andClabis the larch plantation was significantly higher than Pinus sylvestris. Because thesoil microbial biomass carbon as the depth increases, the larch plantation soil easilydegradable organic carbon pool smaller, but Pinus sylvestris has the trend of gettinglarger and larger, the trend is more obvious of the Clab. With soil depth, the larchplantation soil organic carbon stability is increasing, but Pinus sylvestris is reducing.