It was shown that the organic content, the specific weight of soil particle and the liquid limit decreased but the plastic limit increased with the increase of the concentration of acid.

试验表明：酸浓度的增加导致有机含量减小，土粒比重减小，塑限增大、液限减小；

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Soil organic matter, soil porosity, availible N, Zn, Fe, Mn and enzyme are all positively related to the amount of straw applied remarkably, while soil specific weight is negatively correlative.

土壤有机质、孔隙度、速效氮、锌、铁、锰、酶活性等理化指标与秸秆还田量呈显著正相关；

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