Study On Effects Of Different Vegetation Restoration Patterns On Soil Active Organic Carbon In Antaibao Opencast Mine

Current studies on soil organic carbon(SOC) in mining areas of China were concentrated on total organic carbon(TOC), whereas the active carbon part, which was very special and important, were less. In fact, compared to TOC, active organic carbon(AOC) could sensitively reflect the influence of external environment changes on soil carbon pool, playing an important role on soil microbial activities, vegetation community growth and growth of regional ecosystem carbon reserves. This paper, through studying on AOC distribution and its correlation with soil nutrient and litters under different vegetation restoration patterns in Antaibao(ATB) mining area(AOC is indicated by easily oxidized organic carbon EOC, which is of low, medium and high activity, and extracted respectively by 333, 167 and 33mmol/L KMn O4), the changes and update degree of soil organic carbon pool in mining reclamation areas are timely and effectively monitored, and the most direct significance to research on carbon effects of vegetation restoration are reflected. This study includes the following results:(1)TOC and AOC are decreased with the increasing of soil depth under different vegetation restoration patterns. TOC(0~50g/kg)>low AOC(6~100mg/kg)>medium AOC(2~55mg/kg) > high AOC(0~5.4mg/kg), which shows that AOC content extracted by 333mmol/L KMn O4 is the highest, and vegetation changes response is the most sensitive. Vegetation restoration significantly improves carbon activity in the surface soil, improving the quality of carbon pool, with SIV(Pinus×Robinia) model shows the best effect. TOC and AOC is closely related, AOC is largely depended on TOC, the response of AOC to small changes of soil carbon pool is sensitive and effective under different vegetation restoration modes, and low AOC expresses the best effect.(2)Effects of vegetation restoration to the content of N, K, and available P are not significant, which to available K and available N significant, and vegetation restoration can improve the p H of mining area soils, making soil properties change towards good direction, with SIV(Pinus×Robinia) model shows the best effect. Relationship between AOC and physicochemical properties is close, with SHR(Hippophae rhamnoides) mode shows the best relevance, and low AOC can more sensitively reflect the minor changes of soil properties. Relationship between litters and AOC is very close, with SIV(Pinus×Robinia) model shows the best correlation.(3)Carbon effects of vegetation restoration are highlighted in mining area, with SIV(Pinus×Robinia) mode shows the best effect, so vegetation restoration in ATB opencast mining area should give priority to the effect of Pinus×Robinia mode on enhancing soil carbon pool activity and quality, followed by the allocation of other vegetation patterns, to realize the healthy and stable development of mining area ecological system.