旱地玉米不同耕作覆盖措施的土壤环境及产量效应

Effects of different tillage and mulch treatments on the soil environment and yield of dryland maize

关键词:  玉米  旱地  耕作覆盖  土壤环境  产量

Key words:  maize  dryland  tillage and mulch  soil environment  yield

摘要:

为解决冷凉区旱地玉米生产中存在的干旱缺水、低温冷凉和土壤肥力下降等问题，于2011—2014年采用裂区设计，在山西省旱作节水农业示范基地——阳曲县河村，设置4种不同耕作覆盖处理，研究旱地玉米不同耕作覆盖处理的土壤水、肥、热及产量效应，结果表明：1）秋深耕+秸秆还田较春旋耕+无秸秆还田明显提高苗期5 cm日平均地温和日最低平均地温，3年平均分别提高1.1和1.3℃。覆膜处理3年平均较不覆膜处理增加苗期5 cm日平均地温和日最低平均地温1.7和1.2℃；2）秋深耕+秸秆还田苗期0~10 cm土壤含水量较春旋耕+无秸秆还田平均增加1.9个百分点。3）玉米苗期秋深耕+秸秆还田0~12.5 cm土壤紧实度平均为春旋耕+无秸秆还田的3.0倍，从15.0 cm开始2个处理土壤紧实度基本一致。4）连续3年耕作覆盖处理后，秋深耕+秸秆还田土壤肥力明显得到改善，其中0~20 cm土壤有机质含量、土壤全磷和全钾都较春旋耕+无秸秆还田有显著（P<0.01）增加，增幅分别为5.8%、6.4%和6.1%，覆膜土壤全氮含量显著高于不覆膜，增幅为8.6%。5）秋深耕+秸秆还田有显著（P<0.01）增产作用，4年平均增加经济产量12.2%，4年覆膜处理较不覆膜处理经济产量平均增加25.3%。所有处理中，秋深耕+秸秆还田+覆膜产量最高。6）覆膜处理中，秋深耕+秸秆还田WUE平均较春旋耕+无秸秆还田增加5.4%；而不覆膜处理中，秋深耕+秸秆还田WUE平均较春旋耕+无秸秆还田增加12.0%。因此，目前适宜该区域的蓄水保墒、增温稳温、培肥地力和高产高效的土壤耕作覆盖措施为秋深耕+秸秆还田+覆膜。

Abstract:

In order to solve the problems of drought and water shortage,low temperature and cold,soil fertility decline and so on in dryland maize production in cold climate areas,the split plot design was adopted in 2011-2014.In the demonstration base of dry farming and water saving agriculture in He village,Yangqu County,Shanxi Province,the effects of different tillage and mulch treatments on soil water,fertilizer,heat and yield of dryland maize with 4 different tillage mulching treatments were studied.The results showed that:1) Deep tillage in autumn plus straw returning (DTS) obviously increased the 5 cm ground temperature at seedling stage compared with rotary tillage in spring with no straw returning (RTN).The average daily ground temperature and average daily minimum ground temperature increased by 1.1 and 1.3℃over 3 years,respectively.Plastic film mulching (PM) for 3 years improved the 5 cm at seedling stage compared with no plastic film mulching (NPM).The average daily ground temperature and average daily minimum ground temperature increased by 1.7 and 1.2℃,respectively.2) Compared with RTN,the soil moisture content of DTS at seeding stage in 0-10 cm increased by 1.9 percentage point.3) The soil compactness of DTS at seeding stage in 0-12.5 cm was equally 3 times of RTN.The soil compactness of the two treatments was basically the same from 15 cm.4) After 3 years of continuous tillage and mulching treatment,the soil fertility of DTS was obviously improved.The content of soil organic matter,total phosphorus and potassium in 0-20 cm were significantly higher than that in RTN (P<0.01),and the increases were respectively 5.8%,6.4% and 6.1%.Total nitrogen content in PM was significantly higher than that in NPM with an increase of 8.6%.5) DTS increased the yield significantly (P<0.01),and the economic yield increased by 12.2% on average in 4 years.The economic yield of PM in 4 years increased 25.3% compared with NPM equally.Among all the treatments,the yield of DTS plus PM was the highest.6) In PM treatment,the WUE of DTS increased by 5.4% compared with that of RTN.And in NPM treatment,the WUE of DTS increased by 12.0% compared with that of RTN.In conclusion,DTS plus PM is appropriate for the area to store water and preserve soil moisture,increase and stabilize temperature,improve soil fertility,and get high yield and high efficiency currently.