Effects Of Vegetation Allocation Model On Soil Organic Carbon In Reclaimed Mining Areas

Soil is the largest carbon pool on land,and mining cause land degradation and soil carbon pool loss.Vegetation restoration can solve the problems related to soil degradation.In order to understand the effects of different vegetation restoration models on soil organic carbon fixation.Abandoned land of Tunlan Coal Mine in Xishan Coal of Shanxi Coal Group was selected as the research area in this research.31 planting configuration modes were selected for vegetation restoration,and the vegetation restoration area(0.62ha)and natural restoration area(0.5ha)were monitored regularly in the long term.Community ecological and soil monitoring data from 2015 to 2017 were studied by correlation analysis method.Effects of vegetation allocation on organic carbon fixation in reclamation area of mining area were explored.The main results were as follows:Vegetation restoration can increase the contents of soil organic carbon,mineralized carbon,microbial biomass carbon(MBC)and labile organic carbon(LOC)in abandoned land of mining area,and increase 56.5%,26.6%,98.8% and 86.3% respectively compared with the initial stage of restoration.There is a significant positive correlation among soil organic carbon,LOC and mineralized carbon(P<0.01).The increase ratse of different vegetation allocation modes were different.The increase of soil organic carbon and active organic carbon by arbor + shrub + herbaceous vegetation is higher,and it can resist the change of external environment.Vegetation restoration can improve soil aggregates and promote the formation of large aggregates.Sabina chinensis,Cerasus humilis and Amorpha fruticosa can increase soil particle size by 0.25-2 mm.The content of > 0.25 mm in aggregates,GMD,MWD and soil organic carbon,mineralized carbon and LOC showed significant correlation(P< 0.01).The effects of vegetation allocation pattern on soil enzymes in vegetation restoration land were different,but they all have certain promotion effects.After vegetation restoration,soil catalase,cellulase and invertase increased by 123.2%,30.5% and 21.6% compared with the initial stage.Soil organic carbon and LOC were significantly correlated with catalase and invertase(P<0.01).Vegetation allocation had a certain impact on species diversity.The number of species in vegetation restoration plots was significantly larger than that in non-vegetation restoration plots.After three years of planting experiment,the species with higher survival rate is Sabina chinensis.In the process of vegetation restoration of abandoned mining land,the plants such as Sabina chinensis,Amorpha fruticosa and Cerasus humilis can be preferentially selected and the vegetation restoration model of arbor,shrub and grass can be used to promote the fixation of organic carbon in soil.