玉米秸秆还田对土壤理化特性影响的研究

Effects of Maize Straw Turnover on Soil Physicochemical Property

试验设置玉米秸秆还田3、6次,每次还田量7500、15000 kg/hm2,通过比较玉米秸秆是否还田、连续、间断还田以及不同还田量的土壤养分含量和理化特性差异,考察玉米秸秆还田培肥地力的效果。结果表明:(1)与不还田对照比较,秸秆还田的土壤有机质、有效N、有效P和速效K含量呈上升趋势,而容重呈下降趋势,其中有效N和速效K含量上升趋势特别明显;(2)连续6年还田的土壤有机质、有效N、有效P和速效K含量分别比间断还田平均提高38.26%、18.73%、51.73%和18.74%,容重平均降低3.87%,采用秸秆连续还田对提高土壤养分含量和改善土壤物理特性的效果比隔年还田更佳;(3)较大还田量(15000 kg/hm2)的土壤有机质、有效N、有效P、速效K含量和总孔隙度分别比较小还田量(7500 kg/hm2)提高18.25%、37.40%、35.45%、19.65%和8.44%,容重降低76.11%,增加秸秆还田数量对土壤养分含量的提高与物理特性的改善效果更加明显。

Maize straw was returned to field 6 times continuously and 3 times discontinuously, the turnover amounts were 15000 and 7500 kg/hm^2. The differences of soil nutrient contents and physicochemicalproperties between maize straw turnover and non-straw turnover, continuous and discontinuous turnover, anddifferent straw turnover amounts were investigated to promote the effect of maize straw turnover. The resultsshowed that：（1） compared with CK（non- straw turnover）, straw turnover could increase the content of soilorganic matter, available N, available P and available K, especially the available N and available K contentincreased obviously, while soil bulk density decreased;（2） continuous turnover treatment increased soil organicmatter, available N, available P and available K by 38.26%, 18.73%, 51.73% and 18.74% respectivelycompared with that of discontinuous turnover treatment, and soil bulk density decreased by 3.87%; theimproving effect of continuous straw turnover on soil nutrient content and physicochemical properties wasbetter than that of discontinuous straw turnover;（3） the content of soil organic matter, available N, available P,available K and total porosity of large turnover amount（15000 kg/hm^2） increased by 18.25%, 37.40%, 35.45%,19.65% and 8.44% compared with that of small turnover amount（7500 kg/hm^2）, while the soil bulk density decreased by 76.11%. The increase of turnover amount had more obvious effect on the improvement of soil nutrient and physicochemical properties.