Study on effect of continuous and multiple cropping of tobacco-rice on soil physical and chemical properties

Location detection in tobacco field and the method of regression analysis were took to research the effect of continuous and multiple cropping of tobacco-rice on soil physical and chemical properties.The results showed that during 0~23 years of continuous and multiple tobacco-rice cropping,soil pH value increased significantly and was in the above 7.5 level.With increasing of continuous and multiple cropping years.Soil physical properties was gradual deterioration.The change of organic matter,nitrogen and phosphorus nutrients,microorganism of soil was complex,it showed a downward trend after 14~18 years of continuous and multiple cropping.The change trend of soil physical and chemical properties was not conducive to the growth of flue-cured tobacco.