土地利用对沼泽湿地土壤碳影响的研究

Land use has been changed drastically under the influence of human activity since the middle of the twentieth century, and it affects soil carbon contents importantly. The effects of land use change on carbon contents in marsh soils in Sanjiang Plain were studied by selecting two typical marshes: Carex lasiocarpa marsh and Deyeuxia angustifolia marsh. The results indicated that soil carbon contents were mostly controlled by water condition and soil carbon contents in Carex lasiocarpa marsh (long-waterlogged marsh) were higher than in Deyeuxia angustifolia marsh (short-waterlogged marsh). Total carbon (TC), soil organic carbon (SOC), soil inorganic carbon (SIC) and dissolved organic carbon (DOC) in Carex lasiocarpa marsh soil were 258.4±81.9、203.7±62.4、54.7±19.4、4.8±0.85 g·kg-1, and which in Deyeuxia angustifolia marsh soil were 99.4±24.2、81.4±24.5、17.9±9.8和2.4±0.27 g·kg-1, respectively. Reclamation led in soil carbon contents decreased remarkably. TC and SOC were both negatively correlative with tillage years. Degradation of marsh resulted in the reduction of soil carbon contents. Marsh restoration increased soil carbon contents, but the rates of TC and SOC were low. Soil pH was an important factors affecting soil carbon.