[Effects of wetland reclamation on amino sugar accumulation in soils of the Sanjiang Plain].
摘要
as well as three agricultural lands cultivated for 5, 15, and 25 years to examine the effects of wetland reclamation on the content of microbial residues (amino sugar analysis). Results showed that soil amino sugar contents were significantly reduced after wetland reclamation, with a positive relationship between the reduction and the duration of reclamation. After 25 years of reclamation, the content of glucosamine, galactosamine, and muramic acid in agricultural soils decreased by 38.0%, 38.1%, and 35.9%, respectively, compared to the natural wetland. The reduction of muramic acid (25.8%) was stronger than glucosamine (14.9%) after 5 years of reclamation, indicating that bacterial-derived microbial residues were more sensitive to wetland reclamation than fungal-derived counterparts in the short term. Total amino sugars were decreased by 21.1%, 34.0%, and 38.0% after 5, 15, and 25 years of wetland reclamation, respectively. The proportion of total amino sugars in soil organic matter was significantly decreased from 4.8% in natural wetland to 4.4% after 25 years of reclamation, indicating that long-term wetland reclamation accelerated the depletion of microbial-derived organic components, and thus changed the composition of soil organic matter. Such changes may affect long-term stabilization of soil organic matter and ecosystem functioning.