【摘要】 以国家土壤质量安定观测实验站黄绵土区的农田长期定位试验为研究平台，研究长期施肥与覆膜对半干旱区马铃薯农田土壤团聚体分布及其有机碳含量的影响。结果表明：耕层土壤团聚体占比随着粒径的减小呈先降低后增加的变化趋势，团聚体有机碳含量随粒径减小呈增加趋势。施肥显著影响马铃薯农田土壤团聚体分布及有机碳含量。长期化肥与有机肥配施（NPK+OM）和单施有机肥（OM）较单施化肥（NPK）显著增加>0.25 mm团聚体含量（R0.25）和平均质量直径（MWD），显著提高大团聚体（>1 mm）对有机碳的贡献率。长期施用有机肥（NPK+OM和OM）较单施化肥（NPK）显著增加0～20 cm土层土壤团聚体有机碳储量，增幅达63.5%～82.8%。长期覆膜导致>2 mm粒径的大团聚体数量和MWD显著下降，覆膜与单施化肥（NPK）对团聚体有机碳含量及其储量影响不明显。综上所述，在西北黄土丘陵半干旱区和黄绵土质地条件下，长期化肥与有机肥配施（NPK+OM）或单用有机肥（OM）可显著提高耕层土壤大团聚体含量（R0.25）及其稳定性，促进新碳向大团聚体富集，增加团聚体有机碳储量，有利于农田土壤固碳。地膜覆盖影响土壤团聚体的分布和稳定性，但对团聚体有机碳影响不明显。更多还原

【Abstract】 Taking long-term farmland positioning experiment in Huangmian soil area of Anding Soil Quality National Observation and Research Station located in Gansu province as the research platform,the effects of long-term fertilization and plastic-mulching on the distribution of soil aggregates and organic carbon content in potato field of semi-arid areas were explored. The results showed that,with the decreasing of aggregates particle size of topsoil,the proportion of soil aggregates was decreased first and then increased,while organic carbon content of soil aggregates was increased. Fertilization significantly affected the distribution and organic carbon content of soil aggregations. Compared with mineral fertilizers(NPK)treatment,long-term mineral fertilizers combined with organic fertilizer treatment(NPK+OM)and single organic fertilizer treatment(OM)all increased significantly contents of >0.25 mm aggregates(R0.25)and mean weight diameters(MWD)of soil aggregates,and improved significantly the contribution rate of large aggregates(>1 mm)to organic carbon. Compared with mineral fertilizer(NPK),long-term organic fertilizer treatments(NPK+OM and OM)increased significantly the organic carbon reserves of soil aggregates in 0～20 cm layer by 63.5%～82.8%. Long-term plastic-mulching decreased significantly the contents of soil >2 mm aggregates and MWD,however,plastic-mulching and single application of mineral fertilizer(NPK) had no obvious effect on the contents and reserves of organic carbon of soil aggregates. In conclusion,under the condition of Huangmian soil of the semi-arid loess hilly region of northwest China,long-term organic fertilizer combined with chemical fertilizer(NPK+OM)or single organic fertilizer(OM)can improve significantly contents of >0.25 mm aggregates(R0.25)and soil aggregate stability,and promote the enrichment of new carbon into large aggregates,which can increase the contents and reserves of organic carbon of soil aggregates,and will be conducive to soil carbon sequestration in farmland. Long-term plastic-mulching will affect the distribution and stability of soil aggregates,but has no obvious effect on the organic carbon of aggregates.更多还原