土层置换对不同作物根际土壤酶及土壤养分的影响

为研究土层置换犁改良土壤后对不同作物根际土壤酶活性及土壤养分含量的影响，分别于6月、8月、10月对作物根际土壤过氧化氢酶、脲酶、蔗糖酶采用常规方法进行测定，并于作物成熟期对土壤养分含量进行测定。结果表明，土层置换可降低3种作物根际土壤过氧化氢酶，脲酶及蔗糖酶活性，3种作物随生育进程过氧化氢酶，脲酶活性变化趋势相同；而蔗糖酶变化趋势不同，大豆根系土壤蔗糖酶随生育进程表现为持续升高，马铃薯和甜菜根系土壤蔗糖酶是先升高后降低；土层置换处理降低了作物根际土壤养分含量的同时对土壤pH有一定影响；土层置换可增加作物产量，与对照相比大豆增产幅度达到20.14%，马铃薯25.00%、甜菜38.89%。因此，土层置换改变了土壤土体结构的同时，可全面活化土壤养分，改变土壤酶活性，对于提高作物产量具有重要作用。

The Effects of the Soil Layer Replacement to the Rhizosphere Soil Enzymes and the Soil Nutrients of Different Crops

In order to investigate the effects of the soil layer replacement to the rhizosphere soil enzymes and the soil nutrients of different crops. The catalase, urease and invertase of soil at June, August, October of crops were determined by conventional method, and the soil nutrient content was determined at mature stage of crops by conventional method. The results showed that: soil layer replacement could decreased the catalase, urease and invertase of rhizosphere soil of crops and the change of catalase, urease were identical. The invertase of rhizosphere soil of crops were different, the invertase of rhizosphere soil of sugarbeet and potato was first increased and then decreased. The soil layer replacement treatment reduced soil nutrient content of rhizosphere soil of crops and changed the pH. The soil layer replacement increased the yield of crops, and the yield of soybean, potato and sugar beet increased significantly by 20.1%, 25.00% and 38.89% compared with CK. Therefore, the soil layer replacement could overall activate soil nutrient and increased soil enzyme activity. The soil layer replacement had main effect to increase the yield of corp.