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以福州平原早、晚稻田为研究对象,分析了秸秆还田对早、晚稻田土壤不同粒级水稳性团聚中TC、TN、TP含量及其计量比的影响。结果表明:秸秆还田之后,早稻土壤各粒级水稳性团聚体中,TC、TN、TP含量以及TC∶TN均不同程度增加,且在1~2 mm粒级水稳性团聚体中,TC、TP含量及TC∶TN分别增加42.3%、22.2%和29.1%(P<0.05);各粒级水稳性团聚体中,TN∶TP均不同程度减小,TC∶TP则无明显变化规律;秸秆还田后,晚稻土壤1~2 mm粒级水稳性团聚体中TC、TP显著降低(P<0.05),而各粒级水稳性团聚体中TC∶TN基本无变化,TC∶TP和TN∶TP则在1~2 mm粒级水稳性团聚体中增大,其余粒级团聚体中减小;从团聚体粒级角度看,早、晚稻土壤中TC、TN、TP主要分布在水稳性大团聚体中(0.25~2 mm粒级),团聚体粒级越小,养分含量越少;秸秆还田后,晚稻土壤水稳性大团聚体对土壤养分贡献率增大,水稳性微团聚体(<0.25 mm粒级)养分贡献率则降低;总体上,早、晚稻田中,1~2 mm粒级水稳性团聚体对秸秆还田响应显著;秸秆还田对福州稻田水稳性团聚体中养分含量有影响,对其化学计量比的影响则不明显。
Taking the early and late paddy fields in Fuzhou Plain as the research object, the effects of straw incorporation on the contents of TC, TN and TP and the ratio of their stoichiometry in different size fractions of early and late paddy soils were analyzed. The results showed that the contents of TC, TN, TP and TC: TN in different water stable aggregates of early rice paddy increased in different degrees after straw returning, and in 1 ~ 2 mm size water stable aggregates, The contents of TC, TP and TC: TN increased by 42.3%, 22.2% and 29.1% (P <0.05) respectively. The TN: TP all decreased in different water-stable aggregates and TC: TP did not change significantly The contents of TC and TP in 1 ~ 2 mm water-stable aggregates of late rice paddy decreased significantly (P <0.05), while the contents of TC:TN in the water stable aggregates of each grade did not change. : TP and TN: TP increased in 1 ~ 2 mm size water-stable aggregates and decreased in the other fractions. From the perspective of aggregate size, TC, TN, TP Mainly distributed in water-stable macroaggregates (0.25 ~ 2 mm particle size), the smaller the aggregate size, the less nutrient content; After straw returning, the contribution of soil water-stable macroaggregates to soil nutrients increased The nutrient contribution rate of large and water-stable microaggregates (<0.25 mm grain size) decreased; in general, the water-stable aggregates of 1 ~ 2 mm size fraction had a significant response to straw returning in early and late paddy fields; Fuzhou rice paddy water-stable aggregates Nutrient content has an impact on the stoichiometric ratio of the impact is not obvious.