Analysis On Carbon Sink Changes Of Forest Management In Lin’an, Zhejiang Province

In recent years, Forest management is getting more attention from the internationalsociety as one of the most potential methods to climate change mitigation, especiallyGreenhouse gas emissions by sources and removals by sinks lead by human activities such asforest management could be used to offset carbon credit promised by Annex I parties with theprocess of climate change negotiation. China has just done some research on forestmanagement carbon inventory, and hasn’t done any research on forest management carbonstorage at regional scale. Thus, This study, On one hand, could provide data support for carbonmitigation project of forest management, On the other, could provide idea for future researchwith the exploratory studies on forest management carbon inventory.This paper estimates carbon storage of forest management in Lin’an, Zhejiang Provinceby adopting carbon storage-change and growth-loss method, the data was got by gatheringforest resource inventory data during1989-2009and parameter data from published literature.Meanwhile, this study calculated carbon credit of forest management which adopted gross-netmethod and net-net method based on1990,2000and the mean value during1990-2000.Besides, this paper discussed how the carbon storage of forest management was effected byharvested wood and force majeure, and explore how the forest management influenced carbonstorage of lei bamboo.The paper provides conclusions as follows:（1）Forest management had high carbon storage and great potential on carbon sink.Carbon storage of forest management on the vegetation per year was in range of4.04-7.27MtC,while the soil carbon storage which was to the depth of1m reached21.70-22.66MtC, this valuewas increased year by year after1994, we predicted the carbon storage would be3MtC muchmore than this value in1990by2020. In the future, the potential of forest management carbonsink would be strengthened, since the ratio of mature forest and over-mature forest, protectionforest and special used forest, nature forest would be increased, which could absorb morecarbon dioxide. （2）The trends of carbon sink change of forest management show as follows: the valuewas negative in1990and1994, which means that forest was carbon source in this two yearswhile converted to carbon sink after1999. Besides, the figure adopting growth-loss methodwas higher than the one under carbon storage-change method. The carbon sink on vegetationwas increased during1990-2020, which was speeded after2009. the value of the carbon sinkon soil was negative in1990and1994while converted to carbon sink after1999.（3）The carbon credits of forest management under different baselines were various, butthe gap was not obvious. The contrastive results under different baselines were similar betweencarbon storage-change method and growth-loss method. The carbon credits adopting the twomethods under this five baseline scenarioes were as follows: net-net-1990〉gross-net-1990〉net-net-average, which were during1990and2000, gross-net-2000〉 net-net-2000〉net-net-1990〉gross-net-1990〉net-net-average, which were during2009and2020. during2000-2009, the results adopting carbon storage-change method were as follows: net-net-1990〉gross-net-2000〉gross-net-1990〉net-net-average〉net-net-2000. while the results of growth-lossmethod were the same as the one during2009and2020.（4）Harvested wood and force majeure had little influence on carbon storage of forestmanagement. The carbon storage of harvested wood was only2.8%-5.0%of forest carbonstorage; the carbon emission after suffering forest fire reached1565Tc per year, accounting for0.03%of the average value of forest management carbon storage; prevention rate of plantdiseases and pests reached over98%.（5）Intensive management measure of lei bamboo had little effect on carbon storage. Thecarbon storage of lei bamboo had been increased during1990-2010, and the carbon storage ofvegetation under intensive management was less than the one based on extensive management,while the carbon storage trend of soil was contray to the one of vegetation. The total carbonstorage under intensive management were6.0Gg much than the one under extensivemanagement.