土体重构对旱田土壤微生物及养分的影响

Soil Reconstruction Influences on Soil Microbes and Nutrients on Upland Field

以旱田土壤为研究对象,探讨常规耕作(CK),0-10cm与10-20cm土层置换(TC1),0-20cm与20-40cm土层置换(TC2),0-30cm与30-60cm土层置换(TC3),0-10cm土层混合(GF1),0-20cm土层混合(GF2),0-30cm土层混合(GF3)对不同层次土壤微生物量、酶活性及土壤养分含量的影响。结果表明,与CK处理相比,土体重构处理能够显著提高土壤微生物量碳氮含量和土壤酶活性,不同层次土壤酶活性与对照处理差异显著;耕翻处理的土壤酶活性明显高于对照处理,但除土壤脲酶含量和GF2处理均未达到显著水平;土层置换处理土壤养分含量随土层深度增加表现出不同的变化趋势,与对照处理相比各层次差异显著,土层置换处理有利于土壤养分含量在不同土层中的均匀分布;土层置换处理对土壤改良效果明显,可提高土壤微生物量碳氮含量,增加土壤酶活性,活化土壤养分。

Upland soil was selected as research object,aimed to explore influences of different soil reconstruction methods on soil microbial biomass,enzyme activity and soil nutrient content of different soil layers.7soil reconstruction treatments were established in northeast upland soil,including conventional tillage（CK）,0-10 cm and 10-20 cm soil replacement（TC1）,0-20 cm and 20-40 cm soil replacement（TC2）,0-30 cm and 30-60 cm soil replacement（TC3）,0-10 cm soil mixing（GF1）,0-20 cm soil mixing（GF2）and 0-30 cm soil mixing（GF3）.The results showed that,compared to CK treatment,soil reconstruction could significantly increase soil microbial biomass carbon and nitrogen content,and soil enzyme activity.Soil enzyme activities of different soil layers significantly differed between soil reconstruction treatments and CK treatment.In soil ploughing treatments,soil enzyme activities were significantly higher than that in CK treatment,but all soil properties except urease content did not differ with those in GF2 treatment.With the increasing soil depth,soil nutrient content of soil replacement treatments showed different trends and significantly differed with that of CK treatment.Soil replacement could lead to uniform distribution of soil nutrient content in different soil layers and improve soil properties,causing increases in soil microbial biomass carbon and nitrogen,soil enzyme activity and activation of soil nutrients.