【作者】 段宇坤；

【导师】 刘景辉； 李立军；

【作者基本信息】 内蒙古农业大学 ， 作物栽培学与耕作学， 2008， 硕士

【摘要】 针对黄河流域旱作农田地表裸露、水土流失严重、水分利用效率低等问题,于2004-2007年在内蒙古清水河县典型旱作农田以传统耕翻为对照,运用连续动态监测与室内指标测定的方法,研究了保护性耕作对土壤理化性质、微生物数量、作物生长和土壤侵蚀的影响,分析了保护性耕作的经济效益。结果如下:1、保护性耕作能够改善土壤物理性质,提高土壤养分含量,增加微生物数量,减少水土流失量,增强蓄水能力,有秸秆覆盖的效果更明显。2、保护性耕作的地温低于传统耕翻,最大降低1.5℃,有秸秆覆盖使地温变化趋向缓和,低温时有“增温效应”,高温时有“降温效应”;留高茬覆盖土壤0-20cm含水率高于传统耕翻1.05个百分点,高于留高茬不覆盖0.76个百分点。保护性耕作降低了0～20cm的土壤容重和紧实度,增加了20～60cm的土壤容重和紧实度,秸秆覆盖可以减缓20～60cm土壤容重和紧实度的增加。3、留高茬覆盖的碱解氮、速效磷和速效钾含量分别较传统耕翻提高5.15mg/kg、1.08mg/kg、16mg/kg,土壤有机质、全氮、全磷、全钾分别较传统耕翻增加0.91g/kg、0.36g/kg、0.15g/kg、1.1g/kg。4、在燕麦抽穗期留高茬覆盖的细菌、真菌、固氮菌、放线菌、纤维分解菌数量依次较传统耕翻增加1.55倍、9.66倍、2.85倍、1.38倍、2.36倍。5、保护性耕作的前两年作物长势不如传统耕翻,叶面积指数低,干物质积累量低;第三年单产增加,留高茬覆盖单产和经济效益较传统耕翻分别增加16.1%和67.6%。6、保护性耕作能够明显减少径流量和土壤侵蚀量。留高茬覆盖的径流量和土壤侵蚀量分别较传统耕翻减少53.6%和65.8%。更多还原

【Abstract】 According to the problem of bare surface、severe soil loss and low yield in dry farmland of Yellow River, continuous dynamic measurement of the effect of conservation tillage on physical and chemical properties of the soil、soil biological properties、crop growth and soil erosion, compared with conventional tillage, typical dry farmland of Inner Mongolia region in 2004~2007. An evaluation is made on the economic benefit of conservation tillage in the region. The results showed:1、Conservation tillage improved physical properties of the soil,increased the content of soil nutrient and soil microbe quantity, decreased soil erosion, strengthened storage capacity.Leaving stubble straw mulching is more obvious.2、Soil temperature was lower in conservation tillage than conventional tillage.it was 1.5℃the most. Soil temperature tends to alleviation under straw mulching, When low temperature has "increases the warm effect", when high temperature has "the temperature decrease effect”; Leaving high stubble straw mulching, the rate of moisture content of 0～20 cm soil layer was1.05% higher than conventional tillage, and was 0.76% higher than leaving high stubble straw unmulching. Conservation tillage reduced 0～20 cm soil bulk density and solidity, but it increased 20～60cm soil bulk density and solidity, straw mulching can mitigation soil bulk density and solidity.3、Soil content of available N Phosphorus and Potassium respectively increase by 5.15mg/kg、1.08mg/kg、16mg/kg; Soil organic matter、total N、total P and total K respectively increase by 0.36g/kg、0.15g/kg、1.1g/kg, as compared with conventional tillage.4、Leaving high stubble and straw mulching, the numbers of bacteria、fungi、azotobacter、actinomyces and cellulolytic bacteria increased by1.55times、9.66 times、2.85 times、1.38 times、2.36 times, as compared with conventional tillage,on heading stage of oats.5、Growth vigor of oats in conservation tillage was weaker than that in conventional tillage in the previous two years, leaf area index and dry matter accumulation were low;In third year, the yield increased. Leaving high stubble and straw mulching, the yield and economic benefit increased 16.1% and 67.6%, as compared with conventional tillage.6、Conservation tillage can significant reduced soil runoff and decreased soil erosion. Compared with conventional tillage, leaving high stubble and straw mulching, capacity of runoff and soil erosion decreased 53.6% and 65.8%.更多还原