武威绿洲灌区冬小麦田土壤水热特征对耕作措施的响应

通过田间定位试验,研究了内陆河武威绿洲灌区不同耕作措施对冬小麦田土壤水热特性和产量的影响。结果表明:免耕秸秆覆盖(NTS)和免耕立茬(NTSS)处理较免耕秸秆不覆盖(NT)、传统耕作(T)和秸秆翻压(TIS)处理具有显著的保墒作用;冬小麦返青至收获期NTS和NTSS处理对土壤具有"降温作用",且气温越高"降温作用"越大;NTS和NTSS处理有利于提高冬小麦产量、穗粒数和千粒质量,分别较T处理显著提高产量15.65%~16.84%和6.98%~12.75%、穗粒数10.93%~12.34%和3.57%~23.41%、千粒质量7.85%~10.13%和5.57%~6.40%,分别较TIS处理提高产量8.01%~11.29%和2.94%~4.25%、穗粒数1.83%~9.50%和0.95%~13.28%、千粒质量1.77%~7.69%和0.40%~3.23%,分别较NT处理提高产量4.56%~9.23%和0.92%~1.04%。免耕秸杆覆盖和免耕秸杆立茬处理具有保水、降温、增产的作用,是适宜该区冬小麦生产的有效耕作措施。

Effects of Different Tillage Systems on Soil Moisture and Temperature in Wuwei Oasis Irrigation Area

Effects of different tillage practices on soil water, soil temperature and yield of winter wheat were studied with field experiments on continental river irrigation area of Wuwei oasis. Results showed that NTS (no-tillage with wheat stubble retention) and NTSS (no-tillage with stubble standing) treatments could significantly improve soil moisture compared to NT (no-tillage without wheat stubble retention); TIS (conventional tillage with stubble incorporated) and T (conventional tillage) treatments, but NTS and NTSS treatments could significantly decreased soil temperature during turning green period to harvest time, and the differences of that between NTS, NTSS treatments and other treatments increased with air temperature increasing. Results also showed the yields of NTS and NTSS treatments significantly increased by 15.65%-16.84% and 6.98%-12.75% compared with T treatment, and the grains per spike of them improved by 10.93%-12.34% and 3.57%-23.41%, thousand kernel mass of them improved by 7.85%-10.13% and 5.57%-6.40%, respectively. Compared to TIS treatment, NTSS and NTS treatments improved grain yield by 8.01%-11.29% and 2.94%-4.25%, grains per spike by 1.83%-9.50% and 0.95%-13.28%, and thousand kernel mass by 1.77%-7.69% and 0.40%-3.23%, respectively. Also, NTS and NTSS treatments improved grain yield by 4.56%-9.23% and 0.92%-1.04% compared with NT treatment, respectively. Therefore, no-tillage with wheat stubble retention and no-tillage with stubble standing were effective tillage measures to improve water resources shortage in Wuwei oasis irrigation area for improving grain yields and WUE.