长期不同施肥方式下土壤有机碳的垂直分布及碳储量
Vertical distribution and storage of soil organic carbon under long-term fertilization
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摘要: 为了研究施肥对土壤有机碳含量的影响, 在湖北省农业科学院南湖实验站进行了25年不同施肥方式的长期定位试验。研究结果表明: 与对照相比, 除单施氮肥与单施有机肥外, 其他施肥方式均提高了0~20 cm土壤有机碳含量与碳储量; 与对照及单施化肥相比, 有机肥配施化肥均提高了0~20 cm及0~100 cm土壤有机碳含量与碳储量。单施化肥与单施有机肥对各土层土壤有机碳含量影响较小, 且土壤有机碳累积少; 而化肥配施有机肥提高了0~20 cm与20~40 cm土壤有机碳含量与碳储量。除对照及氮磷钾肥配施过量有机肥处理外, 其他处理土壤全氮与有机碳含量间具有显著相关性。有机肥与化肥配合施用是提高农田土壤有机碳, 增加土壤碳储量的有效方法。Abstract: To determine the effect of different fertilization schemes on soil organic carbon content and storage, long-term fertilization experiment were carried out in Nanhu Experimental Station, Hubei Academy of Agricultural Sciences. With the exception of single application of nitrogen or manure, soil organic carbon content and storage in the 0~20 cm soil layer increase under fertilization compared to the control. Soil organic carbon content and storage in the 0~20 cm and 0~100 cm soil layers increase under combined application of chemical fertilizer and manure compared to the control and single application of chemical fertilizer or manure. Soil organic carbon content is less affected and storage is lower with single chemical fertilizer or single manure application in all the soil layers. However, soil organic carbon content and storage in the 0~20 cm and 20~40 cm soil layers are higher under combined application of chemical fertilizer and manure. Except for the control and combined application of chemical fertilizer and excessive manure, significant positive correlations (P<0.05) are noted between soil total nitrogen and organic carbon content under other fertilization schemes. In conclusion, combined applications of chemical fertilizer and manure should be advocated to enhance agricultural soil organic carbon storage.