Carbon Sink Function And Improvement Measures Of Low-function Plantation In Aohan

Forest is the most important carbon pool in the terrestrial ecosystem. The quality and area of forest affects the forest ecosystem carbon storage. Increasing forest area and improving the forest quality are good to slow down global warming. Most trees planted in early years were low function due to a lack of theoretical guidance in China. The low function plantation seriously affects the overall efficiency of the forestry and forest carbon sequestration. And it holds a large proportion in china plantation. Therefore,it is significant to modify the low function plantation. This paper gave a comparative analysis to low function and normal plantation and estimated the carbon density of low function plantation in Aohan county, Chifeng city.The structure optimization of tree species had been carried out by considering the economic,social and ecological benefits And the structure of species was optimized, the suggestion of transformation was proposed.(1)The study showed that the low function plantation was significant lower than the normal in five indicators(diameter at breast height,canopy,canopy density,stand density, annual average increments)(p<0.05).(2)This study analyzed the ecosystem carbon density of low function plantation. The results showed that the carbon density sequence of different layers were ranked as soil layer> tree layer>shrub layer>herb layer>litter layer and different DBH were ranked as mid DBH>big DBH>small DBH.(3)The difference of carbon density between low function plantation and the normal achieved a remarkable level in each layer (p< 0.01/The carbon density of normal plantation was higher than the low function in different layers except the herb layer. The difference of two stands was mainly on shrub and tree layer.(4)The existed proportion of low function plantation was optimized based on carbon sequestration,ecological,economic and social benefits by using AHP method.The optimized Populus simonii, Pinus Tableulaeformis were 0.33 times and 0.45 times higher than before respectively.The optimized Ulmus pumila,Prunus sibirica,Hippophae rhamnoides,Caragana microphylla, Populus simonii+Caragana microphylla mixed plantation,Pinus Tableulaeformis+Hippophae rhamnoides mixed plantation were 8.48 times,46.78 times,5.33 times,2.05 times,14.65 times and 13.81 times higher than before respectively.(5) According to the distribution of low-function forest characteristics,land occupation condition etc,under the guidance of near natural theory and forest health theory,through the investigation of the normal forest afforestation model,put forward the improvement measures of different low-function stands.