The Research Of Organic Carbon Density Of Soil And Influcing Factors Of Main Forest Community Type In Greater And Lesser Khingan Mountains

Forest ecosystem is the main body of the terrestrial ecosystem, the forest carbon Pool includes forest soil carbon Pool and Vegetation Carbon Pool, and the soil carbon sequestration of forest occupied the two-thirds of forest Carbon. The forests of high-latitude of Northern Hemisphere are generally regarded as an important "sink" for carbon dioxide in the atmospheric. The ecosystem in the high-latitude and high altitude areas owns the most soil carbon density and carbon storage in china. Greater and Lesser Khingan Range areas are the most important forest zone in north of China, and the evaluation of carbon sink capacity owns the most significance. Natural forests are the main body of the forest resources which possesses a serial of ecological functions, such as keeping the water and soil, maintaining biological diversity and so on. Per survey, sampling and test of typical coenotype of natural forest cover in the selected areas of Greater and Lesser Khingan Range, and use the actual measured data to research the soil carbon density, impact factor and carton storage, preliminary conclusions are defined:(1) Average soil carbon density of main coenotype of natural forest in Greater and Lesser Khingan Range is17.03kg/m2, and the average soil carbon density of seven kinds of main coenotype of natural forest of Greater Khingan Range is17.26kg/m2, and the average soil carbon density of eight kinds of main coenotype of natural forest of Lesser Khingan Range is16.79kg/m2.The sequence of carbon density of Greater Khingan Range is Pinus pumila pine (20.65)>larix gmelinii pine (18.93)>Pinus sylvestris pine (18.74)>Populus davidiana Dode pine (16.61)> Birch pine (16.35)> larix gmelinii pine-Birch pine>Quecus mongolica pine (15.32).The sequence of carbon density of Lesser Khingan Range is broad-leaved red pine (21.20)>shaw pine (18.88)> Spruce them pine (17.59)>Populus davidiana pine(15.61)>Betula platyphylla pine (14.52)>Mongolian oak pine (13.94)>Black HuaLin (13.70); Per analyzing the difference of soil carton density of different forest coenotype from the angle of succession of stand, with the conducting of succession of stand, the soil carton density shows a increasing tendency, and reach to maximum in the coenotype of original steady state. From angle of vegetation category to analyze the carton density difference of different coenotype category, the carbon density of coniferous pine is generally greater to the broad-leaved pine.(2) Per the influencing factor analysis of soil carton density for three kinds of typical coenotype (larix gemelinii, Betula platyphylla pine, broadleaved Korean pine) of Greater and Lesser Khingan Range, the conclusion is defined: Per the Principal component analysis of the bio-meteorological factors, the result shows that:the contribution rates of the first principal component of bio-meteorological factors of the three kinds of community types are all above50%, and in that three kinds of community types, four factors, Bio-1、7、11、12, all have the maximum contribution rates of the first principal component;Soil carbon density is the negative correlation to the average annual temperature and positive correlation to the average annual rainfall; soil carbon density of A-type layer is significantly affected by annual air temperature and average annual rainfall, and carbon density of B-type layer is less affected by the climatic factors, The soil carbon density reduced following the increase of temperature in difference, however the soil carbon increased following the increase of average temperature of coldest quarter; Soil carbon density of A-type layer is significantly positive correlation to the altitude and has a high degree of correlation, soil carbon density of B-type layer has a increasing tendency according to the increasing of altitude height, but the increasing tendency isn’t obvious and degree of correlation is low. Soil carbon density shows a little deceasing tendency according to the increasing of slope, and in all selected pine, it is low degree of correlation between larix gemelinii and Betula platyphylla forest, and it is high degree of correlation between soil carbon density and slope for the Korean pine forest leaf, and the degree of correlation between soil carbon density and slope of A-type layer is higher than the B-type layer.It is the highest degree of correlaiton between soil carbon density and canopy density in thebroadleaved Korean pine forest,however there is a very low degree of correlation between soil carbon density and canopy density in the larix gemelinii and Betula platyphylla forest.Soil bulk density of A-type layer is significantly lower than B-type layer, and there is a significant negative correlation between soil carbon density and bulk density, but the degree of correlation is very low. It is significant power exponent negative correlation between soil carbon density and bulk density in different type layers and the degree of correlation is very high. The PH of soil in A-type layer is significantly lower the B-type layer, and shows a significant negative correlation between soil carbon density and PH, but the degree of correlation is very low; It is a significantly positive correlation between soil carbon density and total nitrogen content, and high degree of correlation between them.(3) The article adopts the area data of timber tree with the Greater Khingan Range’s forest group as a unit statistic in the Seventh National Forest Resource Inventory, and Forest census of Yichun Forest Administration area in2006. Utilizing the average carbon density obtained from actually test and preliminary estimates the soil carbon storage of Greater and Lesser Khingan Range:there is a same order between amount of the soil carbon storage and size of distribution area in the main coenotype of Greater and Lesser Khingan Range, the soil carbon storage from high to low in Greater Khingan Range is larix gemelinii> populus davidana forest> mongolian oak forest>Mongolica forest, and he soil carbon storage from high to low in Lesser Khingan Range is theropencedrymion>betula platyphylla Spruce them> larch forest> broad-leaved pin forest> mongolian oak forest.