Analysis On Soil Organic Carbon Characteristics Of Larix Gmelinii

This paper takes the Daxinganling Forest Ecosystem National Field Observation and Research Station as the research area,and selects different forest types(Ledum palustre-Larix gmelinii Forest,Rhododendron danricum-Larix gmelinii Forest,Grass-Larix gmelinii Forest)and no by field sampling and laboratory experiments.The Larix gmelinii Forests of the same age group(young forest,middle-aged forest,near-mature forest,mature forest)were studied,and the physical and chemical properties of soil organic carbon in the Daxinganling original forest area were obtained.Using SPSS,Excel and other software to analyze and process the data,the research results areas follows:(1)Characteristics of soil organic carbon content and density distribution in different age groupsThe changes of soil organic carbon content in different age groups were obvious.The soil organic carbon content of each age group decreased with the increase of soil depth.The order of average organic carbon content in the various age groups of Ledum palustre-Larix gmelinii Forest was:middle-aged forest(81.51 g/kg),young forest(57.83g/kg),mature forest(47.89g/kg),near-mature forest(44.30g/kg).The soil organic carbon density of each age group decreased with the increase of soil depth.The order of average organic carbon density is:middle-aged forest(12.53kg/m2),mature forest(10.90 kg/m2),near-mature forest(9.96kg/m2),young forest(9.48kg/m2).The density of organic carbon showed a change with the increase of the age group and then decreased and then increased.(2)Characteristics of soil organic carbon content and density distribution in different forest typesThe changes of soil organic carbon content in different forest types were obvious.The organic carbon content and density show a decreasing layer by layer as the depth of the soil increases.The order of organic carbon content was:Rhododendron dauricum-Larix gmelinii(99.65g/kg),Ledum palustre-Larix gmelinii forest(75.82g/kg),grass-Larix gmelinii forest(34.25g/kg).The average organic carbon density is:Rhododendron dauricum-Larix gmelinii forest(18.68kg/m2),Ledum palustre-Larix gmelinii forest(12.53 kg/m2),grass-Larix gmelinii forest(5.98kg/m2).(3)Correlation between soil organic carbon content and physicochemical properties.Soil bulk density and pH value were negatively correlated with soil organic carbon content(P<0.01).As soil depth increased,soil bulk density and pH value increased,while organic carbon content decreased.Soil porosity,soil moisture content and soil organic carbon content showed extremely significant positive correlation(P<0.01).With the increase of soil depth,soil porosity and soil moisture content decreased and organic carbon content decreased.