秸秆深埋对不同氮肥水平土壤蔗糖酶活性的影响

Effects of Straw Buried Deep on Invertase Activity in Soil with Different Nitrogen Fertilizer Levels

为探讨秸秆还田后土壤蔗糖酶活性的变化规律及对不同施氮水平的响应,试验采用裂区试验设计,设置无秸秆、秸秆深埋2个因素,4个氮素水平(0、135、180、225 kg/hm^(2))。结果表明:土壤蔗糖酶活性呈现随玉米生育期的延长先上升后下降趋势,在拔节期达到最高,抽雄期开始逐渐下降,在收获期达到最低。与无秸秆处理相比,秸秆深埋处理可以显著提高土壤蔗糖酶活性,且随着施氮肥水平增加可显著提高土壤蔗糖酶活性(P<0.01),在施氮水平为180 kg/hm^(2)时,土壤蔗糖酶活性达至最大最高,为329.09 mg/(g·24 h),提高幅度最高可达19.83%。在秸秆深埋处理下增施氮肥可以提升土壤有机质含量,施肥量在180 kg/hm^(2)土壤有机质达到最高水平,为37.08 g/kg。通过相关分析得出,秸秆深埋与施氮水平交互对有机质含量及土壤蔗糖酶活性呈显著正相关,土壤蔗糖酶活性具有能够反映出土壤有机质含量动态变化的可能性。秸秆深埋处理对于土壤蔗糖酶含量具有增益作用,土壤蔗糖酶活性可以用来作为表征土壤有机质含量的养分指标之一。

To explore the changing law of soil invertase activity and the response to different nitrogen levels after returning straw to field,the test adopted a split zone test design with two factors of no straw and straw buried deep,and each factor had 4 nitrogen levels(0,135,180 and 225 kg/hm^(2)).The results indicated that the soil invertase activity showed a trend of first increasing and then decreasing with the extension of the corn growth period,reached the highest in the jointing stage,gradually decreased in the harvest period,and reached the lowest in the harvesting stage.Compared with the no straw returning treatment,the straw buried deep treatment could significantly increase the soil invertase activity,and with the increase of nitrogen fertilizer level,it could significantly increase the soil invertase activity(P<0.01),when nitrogen application level was 180 kg/hm^(2),the activity of soil invertase reached the highest value,which was 329.09 mg/(g·24 h),and the increase rate was up to 19.83%.Adding nitrogen fertilizer under the straw buried deep treatment could increase the content of soil organic matter.The amount of soil organic matter reached the highest level of 37.08 g/kg at the fertilizer application level of 180 kg/hm^(2).Through correlation analysis,it concluded that the interaction between straw buried deep and nitrogen application level had a significantly positive correlation with organic matter content and soil invertase activity,and soil invertase activity had the possibility of reflecting the dynamic changes of soil organic matter content.Therefore,the straw buried deep has beneficial effect on the content of soil invertase,and the activity of soil invertase could be used as one of the nutrient indexes to characterize the content of soil organic matter.