Carbon Storage Of Major Sand-fixing Forests In MU US Sand Land

Pinus sylvestris was one of the main sand-fixing forests in Mu Us Sand Land, which had large carbon storage. Artemisia ordosica and Sabina vulgaris vegetation got higher carbon flux, and they played an important role in ecological recovery here. This study took the same age Pinus sylvestris and same site condition Artemisia ordosica and Sabina vulgaris vegetation as the research object. The carbon content rate and carbon storage in different organs, litter and soil had been measured after investigating and sampling the material. Carbon storage and its spatial distribution of vegetation and soil in different stands had been analyzed. The results as follows:(1)Carbon storage of Pinus sylvestris stand was 74.17 t·hm-2, and the order of its spatial distribution was vegetation carbon storage, soil carbon density, litter carbon storage, their value were 54.88t·hm-2, 19.26t·hm-2 and 2.2t·hm-2 respectively, this reflected vegetation carbon storage was the major part of total carbon storage.(2)Its average carbon rate was 0.5141, and the order of plant organ carbon rate was: root(0.5208)>trunk(0.5197)> leaf(0.496)>branch(0.4883), litter(0.222) was lowest, which was accounted 2.32 times by plant carbon rate. Soil average carbon rate was 4.5g·kg-1, order of every soil layer was:0-15cm(6.9g·kg-1)>15-30cm(4.5g·kg-1)>30-50cm(2.8g·kg-1).(3) Carbon storage of Pinus sylvestris stand in three different site were 72.3 t·hm-2(lower windward), 51.2 t·hm-2(upper windward) and 98.86 t·hm-2(interdune), their soil carbon density were 18.59 t/hm2, 15.66 t/hm2, 23.53 t/hm2 respectively. Litter carbon density were 2.11 t·hm-2, 1.46 t·hm-2 and 3.03 t·hm-2 respectively. Litter carbon storage had a positive correlation with soil carbon storage, which showed quality and quantity of litter affected soil carbon storage. In addition, every soil layer of these carbon density were higher than stable land between 161% and 605.2%, which showed Pinus sylvestris could improve soil characteristic and increase soil carbon storage under its continuous growth and metabolism.(4) Plant carbon rate of Artemisia ordosica was 0.4968, order of its organ carbon rate was root(0.5046), leaf(0.4954), branch(0.4887). Sabina vulgaris was 0.5145, order of its organ carbon rate was leaf(0.5202), root(0.518), branch(0.5053). Different organ carbon rate in Sabina vulgaris was always higher than Artemisia ordosica, which showed there was difference in organ carbon rate, and no unified rule.(5)Artemisia ordosica vegetation system carbon storage was 1.871 kg·m-2, 2.749 kg·m-2 in Sabina vulgaris vegetation system. Artemisia ordosica soil carbon density accounted for 86.05% of forest carbon density. However, 70.21% in Sabina vulgaris, these showed Sabina vulgaris could accumulate lager carbon storage, but its ability of transforming carbon to soil was less than Artemisia ordosica. And every layer of soil carbon density in Artemisia ordosica community was higher than Uncovered sand between 161% and 605.2%, 110.3%-226.1% in Sabina vulgaris. Their total soil carbon storage accounted 2.06 times and 2.47 times of stable land, these not only did demonstrate difference at same layer, but also similarity in spatial distribution in soil carbon storage under various shrubs.