Effects Of Different Litter Treatment On Soil Organic Carbon Content

The concentration of greenhouse gases in the atmosphere,the global temperature rises significantly,the warming of the climate and the rise of sea level,the uneven distribution of precipitation and the frequent occurrence of extreme weather are the main environmental problems that human beings are facing.Research on the role of soil carbon in the regulation of climate change is increasing.Forest is the largest carbon storage and carbon sink in terrestrial ecosystems,and the change of climate has a great impact on the decomposition rate of litter,and an important source of organic carbon in forest soil is the organic carbon produced by litter decomposition.The amount of carbon released from the litter of the aboveground parts and the dead root of the underground parts of the world are basically equal to 70% of the total carbon circulation of terrestrial ecosystems.The effect of litter decomposition on soil organic carbon content is of great significance for increasing soil carbon sequestration and controlling global warming.The study selected the Jiaozuo north mountain Pinus tabuliformis plantations,Quercus acutissima plantations and the Ruyang Dahuling Quercus acutissima plantations as the research object.In 17 months,we set up four different litter treatments including litter(DL),removing litter(NL),removing litter and root(NI)and control(CK)to study the changes of soil organic carbon content under the conditions of different litter treatment.By the method of litter burying bag method,we analyse the relationship between litter decomposition rate and soil organic carbon content.The effects of different litter input on soil organic carbon content were explored to provide a theoretical basis for increasing soil carbon sequestration function.The results of the study are as follows:1)The soil organic carbon content and carbon density of three stands decreased with the increase of soil depth on the soil profile,and the density of organic carbon in the surface of the forest land was the largest and deep soil organic carbon content is relatively small.Soil organic carbon content in Quercus acutissima plantations in the same area is higher than that in Pinus tabuliformis plantations.The organic carbon content of Jiaozuo Quercus acutissima plantations is higher than that of Ruyang Quercus acutissima plantations.2)Adding or removing litter changed the content of soil organic carbon in 17 months,but the increase is not obvious at the later stage.There has a significant correlation between litter decomposition rate and soil organic carbon content in the topsoil,and no significant correlation with deep soil.The content of soil organic carbon after litter adding was positively correlated with litter decomposition rate,and negative correlation after litter removed.3)The soil organic carbon content of Jiaozuo Pinus tabuliformis plantations and Quercus acutissima plantations increased by 15.2% and 31.8% after adding litter in 17 months,and Ruyang Quercus acutissima plantations increased 17.3% after adding litter in 16 months.After the removal of litter,Pinus tabuliformis plantations and Quercus acutissima plantations in Jiaozuo decreased 15.1% and 1%,the Ru Yang Quercus acutissima plantations decreased by 18.7%.The positive effect of adding litter on soil organic carbon content was obvious,but the effect of litter removed on soil organic carbon content was not statistically significant in part of deep soil,but it still decreased relative to CK.The soil organic carbon content was not significantly reduced after the removal of litter and root,and some soil layer of the stands were increased.