Effects of Rice Straw Incorporation on Soil Physical,Chemical and Biological Properties in Double Cropping Paddy Fields

To study the effects rice straw incorporation measures(e.g.,total rice straw incorporation,rice straw incineration and rice straw no-incorporation) on soil physical,chemical and biological properties in a double cropping paddy field with the same N,P,K fertilizer,the field experiment was conducted from 2010 to 2011.The results showed that rice straw incorporation treatment for two year(four crops) improved soil physical properties,and increased soil organic matter,carbon content of different forms and the content of soil alkaline hydrolysis nitrogen,available nitrogen and slowly available potassium in the soil arable layer.Results indicated that rice straw incorporation treatment field was more than rice straw incineration and rice straw no-incorporation in total amount of three groups of soil microorganism.In rice straw incorporation field,the amount of soil bacteria and soil fungus increased,while that of soil actinomyces reduced.Soil invertase activity significantly increased,while soil urease and catalase activity changed little.By correlation analysis,it showed that soil urease activity had a significant correlation with soil total N,soil invertase activity had a significant or very significant correlation with soil organic matter,total N,soil catalase activity had a significant or very significant correlation with soil total N,alkaline hydrolysis nitrogen and available potassium.