摘要： 采用中子测水技术与蒸发模拟微区相结合的农业物理学法,测得晋中旱地玉米生育期耗水量为300～350mm,其中玉米蒸腾耗水占40～50%,棵间土壤蒸发耗水占50～60%.土壤湿度越大,棵间土壤蒸发越高.浅层土壤水分蒸发较强,深层蒸发较弱.130～150cm土层蒸发几乎未波及到该层.玉米蒸腾与土壤蒸发耗水虽有一定联系,但基本上属于两个独立的过程.蒸腾与产量之间呈高度正相关.农田水分平衡状况对产量有明显的影响.

关键词: 旱地, 玉米, 耗水规律, 水分平衡, 农业物理学法

Abstract: This experiment used the agricultural physics method combining the moisture determining technique by neutron with the simulant microplot evaporation. The results showed that on non-irrigated land in the central region of Shanxi maize total water consumption was about 300 to 350mm in the whole growing period, water consumption from maize transpiration taking up 40%to 50% and water consumption from soil evaporation among plants 50% to 60%. The higher soil moisture was, the more soil evaporation among plants was. The results also showed that water evaporation was stronger in shallow soil and weaker in deep soil and that there was hardly any evaporation in the soil layer of 130 to 150cm. Although maize plant transpiration had some relations with soil evaporation, they belonged to two independent processes basically. Transpiration was significantly correlated with yield. The farmland hydrological balance "had an obvious effect on yield.

Key words: Moil-irrigated land, Maize, Water consumption, Hydrological balance, Agricultural physics method