This study was supported by the National Natural Science Foundation of China (No. 31870576) and the Natural Science Foundation for Distinguished Young Scholar of Zhejiang Province (No. LR18C160001)
【Objective】 Nutrients addition to soil have a significant effect on soil organic carbon mineralization. However, the response of soil organic carbon priming effect(PE)to the addition of different nutrients and its mechanism is still not clear.【Method】 Urea and sodium dihydrogen phosphate were selected as exogenous nutrients and the effects of nitrogen addition, phosphorus addition and nitrogen combined phosphorus addition on soil organic carbon (SOC) mineralization, (PE), microbial function and soil physicochemical properties in a Moso bamboo plantation soil were investigated through an 80-day incubation experiment.【Result】 Nitrogen, phosphorus and their interaction significantly increased the cumulative CO2 emissions of native SOC mineralization (by 91.33%, 19.18% and 94.88%, respectively), resulting in a cumulative positive PE. The magnitude of positive PE induced by nitrogen and nitrogen combined with phosphorus was greater than that induced by phosphorus alone. The above three nutrient addition treatments all significantly increased soil pH, labile organic carbon pool (microbial biomass carbon, dissolved organic carbon and O-alkyl C), carbon-degrading enzyme (β-glucosidase and invertase) activities and cbhI and GH48 functional gene abundance, but inhibited the activity of polyphenol oxidase and RubisCO enzymes. Also, soil inorganic nitrogen content (NH+4-N and NO-3-N) was enhanced under nitrogen and nitrogen combined phosphorus treatments but reduced under phosphorus treatment. Results of Spearman correlation analysis showed significant positive relationships between cumulative PE and soil pH, labile organic carbon, inorganic nitrogen content, carbon-degrading enzyme activities, cbhI and GH48 functional gene abundances, whereas the activities of polyphenol oxidase and RubisCO enzyme were negatively related to cumulative PE.【Conclusion】 The addition of nitrogen and phosphorus nutrients may have enhanced the rate of native SOC mineralization by affecting soil pH, the content of labile carbon and nitrogen, and stimulating the activity and function of microorganisms.
姚易寒,张少博,周家树,刘娟,蔡延江,李永夫.氮磷添加对毛竹林土壤有机碳矿化及其激发效应的影响[J].土壤学报,2023,60(4):1088-1100. DOI:10.11766/trxb202205060034 YAO Yihan, ZHANG Shaobo, ZHOU Jiashu, LIU Juan, CAI Yanjiang, LI Yongfu. Effects of Nitrogen and Phosphorus Addition on Organic Carbon Mineralization and Priming Effect in a Moso Bamboo Plantation Soil[J]. Acta Pedologica Sinica,2023,60(4):1088-1100.复制