无机肥配施粪肥对华北褐土团聚体分布及有机碳含量的影响

为研究无机肥配施粪肥对华北褐土团聚体分布、稳定性及对土壤有机碳（Soilorganiccarbon，SOC）保护性机制的影响，于2012年采自河北省徐水县试验站冬小麦一夏玉米定位试验田进行了试验。设置1个空白对照CK，1个单施化肥处理N10，4个粪肥与化肥配施处理M1N9、M2N8、M3N7、M5N5，采集0～20cm耕层土样，测定土样团聚体稳定性和SOC含量。结果表明：单施化肥不能明显提升土壤中SOC含量；配施粪肥能显著地提高R0.25和大团聚体中OC（Organiccarbon）的含量。M3N7处理能显著提高团聚体平均重量直径（Meanweightdiameter，MWD）、几何平均直径（Geometricmeandiameter，GMD）和各级团聚体中OC的含量。M2N8、M3N7、M5N5处理中SOC主要分布在2-0．25mm的大团聚体上，CK处理中SOC主要分布在微团聚体上，大团聚体含量较低，说明微团聚体比大团聚体形成的早，稳定性高于大团聚体，验证了微团聚体通过胶结作用形成大团聚体的层次性机制。该褐土的团聚体一SOC相互作用说明大团聚体的层次性形成和稳定性对SOC的保护具有关键作用。

The Effect of Fertilizer Management Practices on Distribution of Aggregates and SOC

The research is about influences of aggregate size distribution and stability and soil organic carbon protective mechanism in cin- namon soil in organic and chemical fertilizer management practices. Soil samples ,which were collected from Xushui station long-term posi- tioning experiment field in Hebei Province, includes 6 treatments ： chemical fertilizer（ N10 ）, four fertilizer management practices which combinated chemical fertilizer with manure, CK. The aggregate size classes were got by dry sieving methods. The results indicated that N10 didn＇t significantly increase the capacity of organic carbon in soil, Organic fertilizer could significantly improve the R0.25 and organic carbon content in large-aggregate. The treat of M3N7 can significantly improve MWD, GMD and organic carbon content in all levels of aggregates, showing the significance of organic fertilizer on forming and maintaining soil aggregates. Organic carbon are mainly distributed in the 2-0.25 mm aggregate size classes and organic carbon content in CK treatment of micro-aggregate is highest. That the formation and stability of mi- cro-aggregate is earlier than large-aggregate, verified the mechanism of large-aggregate forming from micro-aggregate through the cemen- tation. The cinnamon soil aggregate-organic carbon interaction is the key factor that the large-aggregate stability and forming with stratifi- cation mechanism, which protect the organic carbon.