施加秸秆与废弃物对茉莉园土壤团聚体及碳氮磷含量的影响

为了研究施加秸秆与废弃物对茉莉园土壤团聚体与碳、氮和磷含量的影响,以福州河滨茉莉园土壤为研究对象,对对照(C)、秸秆(S)、秸秆+石膏(SG)、秸秆+生物炭(SB)和秸秆+炉渣(SS)5种处理样地0—10,10—20,20—30cm土层土壤团聚体分布和稳定性,包括0.25mm团聚体含量(DR0.25)、平均质量直径(MWD)、几何平均直径(GMD)、分形维数(D)以及土壤碳、氮、磷含量和化学计量比进行了测定分析。结果表明:5种处理团聚体均以0.053~0.25,0.25~2 mm粒级为主。与对照相比,单施秸秆团聚体DR0.25、MWD和GMD值分别减小了19.86%,19.18%和37.98%,D增加了14.26%,团聚体稳定性降低;秸秆+石膏、秸秆+生物炭和秸秆+炉渣与单施秸秆相比,DR0.25和MWD相差不大,GMD较单施秸秆分别增加了2.34%,0.63%和12.67%,D分别减少了2.31%,6.26%和5.01%,团聚体稳定性增强。秸秆、秸秆+石膏、秸秆+生物炭和秸秆+炉渣与对照相比,0—10cm表层土壤碳、氮、磷含量均显著增加,10—20,20—30cm土层变化不大,表现为养分向表层富集的现象。综合比较分析,石膏、生物炭和炉渣可以作为秸秆还田配施改良剂,以提高秸秆还田的功效。

Effects of Straw and Waste Application on Soil Aggregates and Soil Carbon, Nitrogen and Phosphorus in the Jasmine Garden

In order to study the effects of straw and waste application on the soil aggregates and soil carbon,nitrogen and phosphorus in the riverside jasmine garden in Fuzhou,the distribution and stability of soil aggregates,including ＞0.25 mm soil aggregates (DR0.25),mean weight diameter (MWD),geometric mean diameter (GMD),fractal dimension (D),and the content and stoichiometric ratio of soil carbon,nitrogen and phosphorus of 0-10,10-20 and 2030 cm soil layers were examined in the control (C),straw (S),straw+gypsum (SG),straw+biochar (SB),straw+slag (SS) amendments plots.The results showed that 0.053～0.25 mm and 0.25～2 mm particles were the predominant contributor.Compared with the control,DR0.25,MWD and GMD under the straw treatments decreased by 19.86％,19.18％,and 37.98％,respectively,whie D increased by 14.26％,and aggregate stability decreased.Compared with the straw amendment plots,in the straw+gypsum,straw+biochar,straw+slag treatments plots,both DR0.25 and MWD varied slightly,and GMD increased by 2.34％,0.63％,and 12.67％,respectively,whereas,D was reduced by 2.31％,6.26％,and 5.01％ respectively,furthermore,aggregate stability also increased.Compared with control,in the straw,straw + gypsum,straw + biochar,straw + slag treatments plots,carbon,nitrogen and phosphorus content were significantly increased in 0-10 cm soil,,however,those in 10-20 and 20-30 cm soil layers varied slightly,showing the accumulation of nutrients to the surface soil layer.In all,the results indicating that biochar and slag can be taken as the combination amendments with straw returning to improve the effect of straw returning.