长期地膜覆盖与不同施肥处理对棕壤活性有机碳的影响

Effects of Long-term Mulching and Different Fertilization Treatments on Active Organic Carbon in Brown Earth

[目的]研究长期地膜覆盖与不同施肥处理对土壤活性有机碳的影响。[方法]采用KMnO4氧化法对沈阳农业大学棕壤长期定位实验站2003年玉米整个生长季内土壤活性有机碳含量的剖面变化进行了研究。试验设覆膜与裸地2种土壤。每种土壤设4个施肥水平,分别为CK、N、M、MNP。其中,CK为对照。N为单施氮肥处理,年施尿素N 270.0 kg/hm2。M为单施有机肥处理,施用的有机肥为厩肥,其有机肥含量为100.0 kg/g左右,全氮含量为10.0 kg/g左右,折合年施N量为270.0 kg/hm2。MNP为有机肥化肥配施处理,年施有机肥N 270.0 kg/hm2,化肥N 135.0 kg/hm2,P2O567.5 kg/hm2。[结果]土壤活性有机碳含量随着季节的变化而变化,剖面分布随深度的增加而下降。长期地膜覆盖使表层土壤活性有机碳显著增加,而对深层影响不显著。无论覆膜与否,不同施肥处理土壤活性有机碳含量变化趋势为:M>MNP>CK>N。有机肥化肥配施和单施有机肥处理都能显著提高土壤表层活性有机碳含量,而单施氮肥则对土壤活性有机碳影响不显著。[结论]地膜覆盖与施用有机肥是提高土壤活性有机碳含量的有效途径。

[Objective] The research aimed to clarify the effects of long-term plastic mulching and different fertilization treatments on the changes of soil active organic carbon.[Method] The changes of soil active organic carbon were determined by using KMnO4 as oxidant in long-term located experiment station at Shenyang Agricultural University in 2003.The soil type was plastic film mulching soil and uncovering soil,and 4 fertilizer treatments was designed per soil type,CK,N,M,MNP treatment respectively.CK was control.N treatment was N fertilizer application treatment,and the year application amount of urea was 270.0 kg/hm2.M treatment was manure application treatment,and the year application amount of manure was 270.0 kg/hm2.MNP treatment was inorganic and organic fertilizers treatment,and the year application amount of manure,N fertilizer and P2O5 was 270.0,135.0,67.5 kg/hm2 respectively.[Result] The soil active organic carbon changed in the corn growth period and decreased with soil depth.Surface soil active orga nic carbon increased remarkable with long-term plastic mulching while no significant change had been found in deeper depth.Whether plastic mulching or not,the change tendency of soil active organic carbon was as follow： M〉MNP〉CK〉N.The content of active organic carbon in soil surface could be enhanced both under application of inorganic and organic fertilizers treatment and under manure application treatment.[Conclusion] Mulching and organic manure were effective to increase the content of soil active organic carbon.