不同耕作处理对土壤微生物、酶活性及养分的影响

为揭示不同耕作处理对土壤微生物、酶活性以及养分的影响,利用大豆为材料,采取两种不同耕作方式为主区,4种中耕方式为副区的裂区试验设计。结果表明：旋耕处理的细菌数量在开花期较翻耕处理降低;旋耕处理的真菌数量在成熟期较翻耕处理提高;而放线菌数量在开花期,翻耕处理较旋耕处理提高,到结荚期却显著低于旋耕处理。翻耕处理的脲酶活性除了在鼓粒期低于旋耕处理,在其他生育期均高于旋耕处理;翻耕处理的土壤磷酸酶活性在结荚期、鼓粒期较旋耕处理提高;翻耕处理的土壤蔗糖酶活性在开花期较旋耕处理提高;翻耕处理在开花期与结荚期的过氧化氢酶（CAT）活性较旋耕处理提高。翻耕处理的速效磷含量较旋耕处理显著提高,速效钾含量旋耕处理较翻耕处理显著提高。在不同中耕措施中,土壤细菌数量在开花期RT1、RT2较RCK显著提高;真菌数量在成熟期PT1、PT2、PT3较PCK降低;各时期的放线菌数量PT2与RT2均较高。在各生育期,PT2、RT2的脲酶活性均较高,在开花期PT2较PCK和RT2较RCK显著提高;土壤磷酸酶活性PT2、RT2在各时期亦较高;土壤蔗糖酶活性在大豆成熟期不同处理均高于各自的CK;在大豆成熟期,PT1较PCK和RT1较RCK的CAT活性提高。不同中耕措施的土壤有机质含量除了RT2显著提高外,其他处理间差异不显著,而碱解氮、速效钾含量PT2、RT2均分别显著高于PCK、RCK。综上可知,PT2组合的耕作处理更有利于保护土壤微环境。

Effects of Different Tillage Treatments on Soil Microorganisms,Enzyme Activities and Nutrients

In order to reveal the effects of different tillage treatments on soil microorganisms, enzyme activities and nutrients, two different tillage methods and four intertillage methods were used as primary tillage and secondary tillage. The results showed that the number of bacteria of rotary tillage decreased compared with that of ploughing in the flowering stage. The number of fungi of rotary tillage was higher than that of ploughing in the mature stage. However, the number of actinomycetes of ploughing increased in the flowering stage and decreased significantly in the podding stage compared with that of rotary tillage. In the podding stage the activity of urease of ploughing was lower than that of rotary tillage, but in the other growth stages were higher than that of rotary tillage. The activity of soil phosphatase of ploughing was higher than that of rotary tillage, which was increased in podding stage and bulging stage. The activity of sucrase of ploughing increased compared with that of rotary tillage in the flowering stage. The catalase activity of ploughing in the flowering and podding stage increased compared with that of rotary tillage. The available phosphorus content of ploughing was higher than that of rotary tillage. The available potassium content of rotary tillage was significantly higher than that of ploughing. In different tillage measures, the number of bacteria in flowering stage, RT1 and RT2 significantly increased compared with RCK. The number of fungi in the mature stage, PT1, PT2 and PT3 decreased compared with PCK. The quantity of actinomycetes increased in both PT2 and RT2 in each growth stage. In each growth stage, the soil urease activities of PT2 and RT2 were all relatively high, and PT2 compared with PCK and RT2 compared with RCK were significantly increased, respectively. The soil phosphatase activity of PT2 and RT2 were all relatively high in each growth stage. Soil sucrase activity was higher than the CK in different treatments in the mature stage. In the mature stages, the catalase activity of PT1 and RT1 was increased compared with that of PCK and RCK. In addition to the soil organic matter content of RT2 was significantly increase, there was no significant difference between other treatments. However, alkaloidal nitrogen and available potassium content were significantly higher than PCK and RCK in PT2 and RT2. In conclusion, PT2 combination tillage treatment is more conducive to the protection of soil microenvironment.