长期施肥下红壤性水稻土固碳效应特征

明确长期施肥红壤稻田碳投入与碳储量、碳含量与产量间的关系,以及不同施肥措施的固碳效率差异。以红壤稻田长期定位施肥试验为试材,用连续监测的方法,测得长期不同施肥水稻产量、土壤有机碳含量和储量,水稻产量数据。所有处理土壤有机碳含量均呈上升趋势,37年后NPKM处理分别比CK、NPK、NPK2高30.5%、23.4%、24.7%;有机碳储量均随碳投入的增加而显著升高;NPK、NPK2和NPKM处理的固碳效率分别为32.7%、25.9%、35.0%;水稻产量与土壤有机碳含量显著直线正相关。双季稻种植模式下,施肥与不施肥处理土壤碳含量和储量均呈上升趋势;化肥与有机肥配施显著提高固碳效率;有机碳含量与水稻产量间显著正相关。

Carbon Sequestration Characteristics of Red Paddy Soil Under Long-term Fertilization

The study aims to identify the relationship between carbon input and carbon storage/carbon content and yields, and the difference of carbon sequestration efficiency of different fertilization tests under long-term fertilization in red paddy soil. The data of rice yield, soil organic carbon content, soil organic carbon reserves and rice yield under different fertilization for a long time were measured by using the method of continuous monitoring. Results showed that soil organic carbon content of all treatments increased, after 37 years, soil organic carbon content of NPKM was 30.5%, 23.4% and 24.7% higher than that of CK, NPK and NPK2, respectively. The storage of organic carbon increased significantly with the increase of carbon input. The carbon sequestration efficiency of NPK, NPK2 and NPKM treatment was 32.7%, 25.9% and 35.0%, respectively. There was a significantly linear positive correlation between rice yield and soil organic carbon content. Soil carbon content and carbon storage of CK and all fertilization tests were on the rise under double-rice planting mode. Carbon sequestration efficiency was improved significantly when chemical fertilizer was combined with organic fertilizer. There was a significantly positive correlation between organic carbon content and rice yield.