通过采集河南省新乡市近郊区域传统耕地、设施菜地以及景观绿化林地和草地0~20 cm表层土壤，利用湿筛法进行水稳性团聚体的分离及团聚体结合有机碳的测定，分析和比较了土壤团聚体稳定性及其结合有机碳变化特征。结果表明：城市化进程中土地利用类型变化对水稳性团聚体粒径组成和稳定性产生显著影响。相较于传统耕地，进行6年设施蔬菜种植显著降低土壤水稳性大团聚体质量占比（WR_0.25）、团聚体平均质量直径（MWD）和几何平均直径（GMD），降幅分别为42.40%、54.84%和129.41%。而进行相同年限景观林、草地建设均能显著提高WR_0.25，提升幅度分别为33.65%和23.63%。景观绿化林地和草地团聚体MWD、GMD较耕地分别增加0.64%和26.92%、83.87%和77.42%。此外，虽然设施菜地和林草地各粒径团聚体结合有机碳含量较传统耕地均有不同程度提高，但是其结合有机碳贡献率变化情况与团聚体各粒径质量占比有关。其中，0.25~2 mm粒径团聚体结合有机碳含量在设施菜地土壤中取得最大值，为35.02 g/kg，但是其>0.25 mm各粒径团聚体结合有机碳贡献率均显著降低。草地建设显著降低<0.053 mm粒径黏粉粒结合有机碳贡献率，但是显著增加>0.25 mm粒径大团聚体结合有机碳贡献率。因此，城市化进程中近郊传统耕地转变为景观绿化林草地初期能促进水稳性大团聚体的形成及结合有机碳的积累，并提高团聚体的稳定性，在土壤有机碳固持方面表现出巨大潜力。

Soil samples at a depth of 0-20 cm were collected from traditional croplands, facility-vegetable lands, landscape greening forests and grasslands in the suburbs of Xinxiang City of Henan Province, and soil water-stable aggregates were separated by wet-sieving method and their associated organic carbon were determined to compare the characteristics of aggregate stability and changes of organic carbon. The results showed that the aggregate mass proportion and stability were greatly impacted by land use types. Compared with traditional cropland, facility-vegetable plantation for 6 years significantly reduced macro-aggregate mass composition (WR_0.25), values of mean weight diameter (MWD) and geometric mean diameter (GMD) by 42.40%, 54.84% and 129.41%, respectively. While the values of WR_0.25 in the same years constructed forest and grassland were significantly increased by 33.65% and 23.63%, respectively. Futhermore, the values of MWD and GMD of forest and grassland were increased by 0.64% and 26.92%, 83.87% and 77.42%, respectively. Compared to traditional cropland, the concentrations of organic carbon associated within aggregates with various sizes were all increased in facility-vegetable plantation, forest and grassland, while their contribution rates of associated organic carbon depended on particle size. The highest organic carbon concentration was obtained in 0.25-2 mm aggregates from the facility-vegetable soil, being 35.02 g/kg, but the contribution rates of associated organic carbon within aggregate fractions >0.25 mm was both significantly reduced. Grassland greatly decreased the contribution rate of aggregates <0.053 mm but significantly increased the contribution rate of aggregates >0.25 mm. In conclusion, cropland converted to landscape greening forest and grassland could promote the water-stable macro-aggregate formation, stability and associated organic carbon accumulation during the early stages, Which indicates a great potential for soil organic carbon sequestration.

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河南省重点研发与推广专项（232102320248）和河南省博士后基金项目（201903042）资助。