不同保护性耕作措施对武威绿洲灌区冬小麦水分利用的影响

2006—2008年通过田间定位试验，研究了武威绿洲灌区不同耕作措施（传统耕作、秸杆翻压、免耕不覆盖、免耕秸杆立茬、免耕秸杆覆盖）对冬小麦土壤水分空间分布、动态变化、作物耗水量、水分利用效率和产量的影响.结果表明：返青至拔节期，免耕秸杆覆盖（NTS）和免耕秸杆立茬（NTSS）处理显著提高了0～30 cm土壤贮水量，处理间差异较大，在小麦拔节后差异变小；返青至成熟期，NTS和NTSS处理30～150 cm土壤贮水量都大于传统耕作处理（T）；播种期，NTS、NTSS和NT（免耕不覆盖）处理0～150 cm土层总贮水量分别比T处理增加29.55～34.69、17.32～21.79和0.89～15.68 mm，收获期分别增加37.59～38.35、5.70～22.14和4.61～13.93 mm，且随着土层深度的增加处理间土壤贮水量差异增大.NTS、NTSS、NT和TIS（秸杆翻压）处理小麦产量分别比T处理提高15.65%～16.84%、6.98%～12.75%、5.88%～11.74%和3.92%～8.16%，水分利用效率分别提高17.15%～17.52%、7.75%～9.65%、8.24%～10.00%和4.17%～9.91%.免耕秸杆覆盖（NTS）和免耕秸杆立茬（NTSS）处理提高了冬小麦产量和水分利用效率，是改善该区域水资源匮乏的有效耕作措施.

Effects of different conservation tillage measures on winter wheat water use in Wuwei oasis irrigated area.

Field experiments were conducted in 2006〖KG-*2〗-〖KG-*7〗2008 to study the effects different conservation tillage measures, including conventional tillage with stubble incorporating (TS), no-tillage without stubble retention (NT), no-tillage with stubble standing (NTSS), no-tillage with stubble retention (NTS), on the soil moisture profile, soil water storage, water use efficiency (WUE), and grain yield of winter wheat in Wuwei oasis irrigated area. Comparing with conventional tillage, NTS and NTSS could significantly increase the water storage in 0〖KG-*2〗-〖KG-*7〗30 cm soil layer from returning green to jointing stage, and increase this storage in 30〖KG-*2〗-〖KG-*7〗150 cm soil layer from returning green till maturity. NTS, NTSS, and NT increased the water storage in whole soil profile (0〖KG-*2〗-〖KG-*7〗150 cm) by 2955〖KG-*2〗-〖KG-*7〗3469 mm, 1732〖KG-*2〗-〖KG-*7〗2179 mm, and 089〖KG-*2〗-〖KG-*7〗1568 mm at sowing, and 3759〖KG-*2〗-〖KG-*7〗3835 mm, 570〖KG-*2〗-〖KG-*7〗2214 mm, and 461〖KG-*2〗-〖KG-*7〗1393 mm at harvesting, respectively. The difference in water storage became more significant with increasing soil depth. NTS, NTSS, NT and TIS increased the grain yield of winter wheat by 1565%〖KG-*2〗-〖KG-*7〗1684%, 698%〖KG-*2〗-〖KG-*7〗1275%, 588%〖KG-*2〗-〖KG-*7〗1174%, and 392%〖KG-*2〗-〖KG-*7〗816%, and the WUE by 1715%〖KG-*2〗-〖KG-*7〗1752%, 775%〖KG-*2〗-〖KG-*7〗965%, 824%〖KG-*2〗-〖KG-*7〗1000%, and 417%〖KG-*2〗-〖KG-*7〗991%, respectively. NTS and NTSS improved the rain water use efficiency and grain yield, being the efficient conservative tillage measures to alleviate the lack of water resource in the study area.