Effects Of Climate Change On Soil Organic Carbon Of Songnen Plain In The Past Century

Based on the songnen plain as the research area, using the New Hampshire university research, the development of the DNDC(Denitrification-Decomposition) model, the UK East significantly of the university of CRU TS3.1 meteorological data in combination with soil properties and LUCC(land use and land cover) data to simulate the songnen plain in 1908, 1930, 1959, 1980, 2000 with 0 to 30 cm and 0 to 50 cm depth farmland soil organic carbon. Analysis of soil organic carbon storage and soil organic carbon density and the time variation, compared the results with the annual average temperature, minimum temperature, precipitation and other meteorological factors were fitted and obtained the following conclusions:(1) One hundred years of Songnen Plain, the average temperature significantly increased; space from southwest to northeast gradually decreasing tendency; the annual average temperature is 0.157℃ /10 a rate and heats up faster in the west and east slowly. The highest temperature increases significantly; on the space from southwest to northeast gradually decreasing; the highest temperature in the annual tendency rate for a 0.101/10 a, warming faster in the west and northeast slower. The lowest temperature significantly increased, the annual minimum temperature fluctuate slightly; space have gradually decline from southwest to northeast; annual minimum temperature tendency rate was 0.225℃/10 a, the temperature rises fast in eastern, western slow. Total annual precipitation is on the decline, the decline was not significant; on the space from southeast to northwest have gradually decreasing; tendency of annual precipitation rate is 0.501 mm/10 a, northwest precipitation in increase, southeast in decrease.(2) One hundred years in Songnen plain land total reserves 0 to 30 cm depth of soil organic carbon was significantly upward trend, the average annual growth of 157.57 ×106t; high in the north and south of the lower on space total reserves 0 to 50 cm depth of soil organic carbon was significantly upward trend, the average annual growth of 197.59 ×106t, the space distribution with similar to 0- 30 cm depth.(3)Songnen plain 0 to 30 cm depth of soil organic carbon density wave ups and downs, for many years the average density of 7255.63 t/km2, but to show significant upward trend in one hundred years. Each year 0 to 30 cm present a similar spatial distribution of soil organic carbon, are smaller in southern, northern is bigger. Each year 0 to 30 cm present a similar spatial distribution of soil organic carbon, are smaller in southern, northern is bigger, 0 to 50 cm depth of soil organic carbon density wave ups and downs, for many years the average density of 9080.96 t/km2, is on the rise significantly, on the space with similar 0 to 30 cm depth.(4)A significant negative correlation between soil organic carbon storage and annual average temperature, annual maximum temperature, minimum temperature, with increasing temperature, soil organic carbon storage decreased; in 1930 and 2000 year, precipitation and soil organic carbon storage was significantly positive correlation; 1908, 1959, 1980 by 0.05 years without inspection, namely the relation precipitation and soil organic carbon storage is not obvious.(5)Soil organic carbon density has significant negative correlation with the average temperature, the highest temperature, the minimum temperature, with the loss of the factors of temperature, soil organic carbon density increases; Soil organic carbon density and the precipitation in each of the different relevance, negative correlation in 1908 and 1959, 1930, 1980, 2000 were positively correlated.With the increase of precipitation, the change of soil organic carbon reserves are not identical, namely the relationship between precipitation and soil organic carbon density is not obvious.