通过季节性冻融期裸地、地膜覆膜地和秸秆覆盖地的田间系列灌水试验,研究了冻融期不同阶段灌水对土壤温度及冻融特性的影响.试验表明:不论何种地表条件,入冬后冻结期较早的灌水地块耕作层土壤温度在整个冻融期处于较低值.消融期,灌水对裸地和地膜覆盖地耕作层土壤温度的影响较小,灌水加速了地表冻层的融化；秸秆覆盖地灌水后土壤温度较低且变幅较小,秸秆覆盖不利于土壤的消融解冻.5 cm土壤累积负温快速增加阶段灌水对于降低土壤最大冻结深度影响非常明显.%A series of field irrigation experiments of bare plot (BP) , plastic film mulched plot(PFP) and corn straw mulched plot(CSP) were conducted during the seasonal freeze-thaw period. The effects of irrigation at different stages on soil temperature and soil freeze-thaw characteristics were analyzed. The results showed that the soil temperatures of plots irrigated earlier in freezing period were lower during the freeze-thaw period. The irrigation had a little effect on the soil temperature of BP and PFP in the thawing period, and the irrigation accelerated the thawing of the surface frozen layer. The soil temperatures of CSP irrigated at thawing period were lower and had a smaller variation. The mulching of corn straw went against soil thawing. The irrigation had a great effect on maximum soil freezing depth in the rapid increasing stage of accumulated negative soil temperature at the depth of 5 cm.
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