闽江河口湿地围垦后土壤微生物残体碳特征
- Characteristics of soil microbial necromass carbon after reclamation of Minjiang River estuarine wetland
- 基金项目：国家自然科学基金项目（面上项目，重点项目，重大项目）
- 摘要：为探究围垦后闽江河口湿地土壤微生物残体碳的变化特征及影响因素，以闽江河口芦苇湿地、稻田和养殖塘为研究对象，对土壤理化性质、酶活性及其微生物残体碳进行测定与分析．结果表明：围垦后，稻田和养殖塘土壤含水量、有机碳(SOC)、电导率显著降低(p < 0.05)，pH值显著升高(p < 0.05)；稻田和养殖塘土壤酶活性显著低于芦苇湿地(p < 0.05)；土壤微生物残体碳对SOC的贡献表现为芦苇湿地和养殖塘土壤真菌残体碳对SOC的贡献显著大于细菌残体碳(p < 0.05)；围垦稻田后土壤微生物残体碳含量变化不显著(p > 0.05)，围垦养殖塘后土壤微生物残体碳含量显著降低(p < 0.05)．湿地土壤微生物残体碳与酚氧化物酶活性(PO)(r = 0.47，p < 0.05)、含水量(r = 0.48，p < 0.05)、SOC(r = 0.76，p < 0.001)、酸性磷酸酶活性(AP)(r = 0.65，p < 0.001)、纤维素水解酶活性(CBH) (r = 0.49， p < 0.05)和β-葡萄糖苷酶酶活性(r = 0.57，p < 0.01) 显著正相关，与pH值(r = -0.64，p < 0.001)显著负相关，与亮氨酸氨基肽酶(LAP)、β-1,4-N-乙酰氨基葡萄糖苷酶(NAG)和电导率相关性不显著(p > 0.05)．本研究可为预测围垦后湿地土壤有机碳组成及稳定性动态变化提供理论支撑．
- Abstract：To explore the characteristics of changes in soil microbial necromass carbon in Minjiang River estuarine wetland after reclamation and its influencing factors, the Phragmite australis wetland, paddy field, and aquaculture pond in the Minjiang River estuary were selected as research objects for the determination and analysis of soil physicochemical properties, enzyme activities, and microbial necromass carbon．The results showed that the soil moisture content, SOC content and electrical conductivity of paddy fields and aquaculture ponds were significantly decreased (p < 0.05), while the pH value was significantly increased (p < 0.05) after reclamation．Enzyme activities of paddy fields and aquaculture ponds were significantly lower than those of reed wetlands (p < 0.05), and the contribution of soil microbial necromass carbon to SOC was that the contribution of fungal necromass carbon was significantly greater than that of bacterial necromass carbon in reed wetland and aquaculture pond (p < 0.05), however, the changes in soil microbial necromass carbon content were not significant (p > 0.05) after reclamation of paddy fields, while the content of soil microbial necromass carbon in aquaculture ponds significantly decreased (p < 0.05)．The wetland soil microbial residue carbon was significantly positively correlated with phenol oxidase (PO) activity (r = 0.47, p < 0.05), moisture content (r = 0.48, p < 0.05), SOC (r = 0.76, p < 0.001), acid phosphatase activity (AP) (r = 0.65, p < 0.001), cellulase activity (CBH) (r = 0.49, p < 0.05), and β-glucosidase activity (r = 0.57，p < 0.01), and significantly negatively correlated with pH value (r = -0.64，p < 0.001)．There was no significant correlation with leucine aminopeptidase (LAP)，β-1,4-N-acetylglucosaminidase (NAG), and electrical conductivity (p > 0.05)．This study can provide theoretical support for predicting the dynamic changes in organic carbon composition and stability of wetland soil after reclamation．
