赤红壤碳库管理的滴灌施氮模式研究

Drip nitrogen fertigation strategy for carbon pool management in latosolic red soil

【目的】探索有利于赤红壤碳库管理的滴灌施氮模式。【方法】通过模拟滴灌系统的盆栽试验,研究了3种滴灌方式和5种施氮处理对土壤有机碳和活性有机碳含量、碳库管理指数和酶活性的影响。【结果】与N0-CDI(土壤施氮量为0结合常规滴灌)相比,N2-ADI(滴灌施氮量0.18 g·kg–1结合交替滴灌)处理土壤有机碳含量提高55.2%,土壤活性有机碳含量提高111.8%,土壤碳库管理指数提高90.5%。同时,土壤有机碳含量、活性有机碳含量和碳库管理指数与过氧化氢酶、脲酶和转化酶活性之间有显著相关性。【结论】滴灌施氮量0.18 g·kg–1结合交替滴灌处理是赤红壤碳库管理的最优滴灌施氮模式。

【Objective】To explore the drip nitrogen fertigation strategy that is beneficial for carbon pool management in latosolic red soil.【Method】Pot experiments imitating the fertigation system were conducted.The effects of three drip irrigation methods and five nitrogen treatments on the contents of organic carbon and active organic carbon,carbon pool management index and enzyme activity in soil were investigated.【Result】Compared with N0-CDI(The amount of nitrogen applied to soil was 0,combined with conventional drip irrigation),N2-ADI(The amount of drip nitrogen fertigation was 0.18 g·kg^-1,combined with alternate drip irrigation)increased soil organic carbon content by 55.2%,soil active organic carbon content by 111.8%and carbon pool management index by 90.5%.Meanwhile,the organic carbon content,active organic carbon content and carbon pool management index significantly correlated with catalase,urease and invertase activities in soil.【Conclusion】The drip nitrogen fertigation of 0.18 g·kg^-1 combined with alternate drip irrigation is the optimal drip nitrogen fertigation strategy for carbon storage management in latosolic red soil.