Dynamic Change Of Carbon Storage In Hulun Buir Sandy Land Natural Pinus Sylvestris Var.mongolica Forests During 1985-2015

The increasing concentration of CO₂ in the air not only causes global warming,but threatens the living environment of human beings,so decreasing the concentration of CO₂ in the air and improve the environment have become the focal point for the countries.As the main carbon pool in terrestrial ecosystem,forests can absorb and fix a mass of CO₂,so study on forests ecosystem carbon sink has become a hot spot of science.Sandy land natural pinus sylvestris var.mongolica forests is an important zoology security for Northern China,play an important role in the wind and sand,carbon fixation.However,there is no study of its carbon storage.And,research on forests carbon storage are more concentrated in national scale and region scale by using data of forest resources inventories,but few research are concentrated in single planting.So dynamic change of natural pinus sylvestris var.mongolica forests in Honghuaerji forestry lbureau and its spatial distribution and dynamic change of carbon storage was studied by using 4 stages（1985,1995,2005,2015）Landsat remote sensing image during 1985-2015,the main conclusions are as follows:（1）Dynamic change of natural pinus sylvestris var.mongolica forests:The area of natural pinus sylvestris var.mongolica forests of 4 stages during 1985-2015 are 33 511.96 hm²,54 695.63 hm²,64 791.33 hm² and 67 970.18 hm².The area increased by 34 458.22 hm² in recent 30 years,the average annual growth rate is 3.43%.Besides,the increase of area is the most on flat land and at the altitude of 700-900m.The area of 4 stages increased first and then dereased with the increasing of the altitude,and decreased with the increasing of the slope.（2）Dynamic change of vegetation carbon storage in natural pinus sylvestris var.mongolica forests:The vegetation carbon storage and density in natural pinus sylvestris var.mongolica forests in 1985 are are 14.48×10⁵t and 43.2 t·hm-2,1995 are are 28.40×10⁵t and 51.91 t·hm-2,2005 are are 37.37×10⁵ t and 57.68 t·hm-2,2015 are 44.02×10⁵t and 64.76 t·hm-2.The increase of vegetation carbon storage is the most on flat land,at the altitude of 800-900m and in half shady slope.The average annual growth rate of vegetation carbon density is the most at the altitude of 800-900m,on flat land and in shady slope.Vegetation carbon storage of 4 stages decreased first and then increased with the increasing of the altitude,and decreased with the increasing of the slope,the regularities of distribution in exposure are half shady slope>shady slope>half sunny slope>sunny slope;Vegetation carbon density of 4 stages decreased with the increasing of the slope,but no regularities was found with altitude and exposure.（3）Dynamic change of soil carbon storage in natural pinus sylvestris var.mongolica forests;The soil carbon storage and carbon density in natural pinus sylvestris var.mongolica forests is 30.56×10⁵t and 91.18 t·hm-2in 1985,1995 are 52.59×10⁵t and 96.15 t·hm-2,2005 are are 63.54×10⁵ t and 98.06 t·hm-2,2015 are 69.3×10⁵ t and 101.96 t·hm-2,soil total carbon storage in natural pinus sylvestris var.mongolica forests is decreasing with years and the increasing rate of soil carbon storage is 4.23%.（4）Dynamic change of total carbon storage in natural pinus sylvestris var.mongolica forests:In recent 30 years,the total carbon storage is increasing and increased by 68.29×10⁵t,increasing rate is 5.06%.Total carbon storage in natural pinus sylvestris var.mongolica forests is decreasing with forest age,but carbon density is increasing with forest age.The results of the above studies illustrate that dynamic change of area,carbon storage and carbon density,as well as spatial distribution characteristics.The study on the carbon storage can provide theoretical basis for evaluating carbon sequestration of natural pinus sylvestris var.mongolica forests and sustainable management.