不同海拔麦田土壤水分变化特征及其对水分利用效率的影响

Effect of Different Altitudes on Characteristics of Soil Water and Water Use Efficiency in Wheat Fields

2017—2018年在晋南4个不同海拔高度的麦田,开展了土壤水分变化特征及对水分利用效率的研究。结果表明:不同海拔麦田不同土层的成熟期土壤贮水量均低于播种期土壤贮水量,在0~100、100~200、0~200cm土层深度不同海拔麦田成熟期土壤贮水量占播种期土壤贮水量的比例分别为47.28%~45.46%、42.49%~77.50%、45.06%~60.96%,其中0~200、100~200cm深度所占比例均随海拔高度的上升而上升;播种期至成熟期0~100、100~200cm土壤耗水量占该阶段0~200cm土壤耗水量的比例分别为51.53%~72.12%、27.88%~48.47%,其中0~100cm深度所占比例随海拔高度上升而上升,而100~200cm则表现为随海拔高度上升而下降;播种期至成熟期0~100、100~200、0~200cm土层耗水量占播种期同一土层贮水量的比例分别为52.72%~54.54%、22.50%~57.51%、39.04%~54.94%,其中100~200、0~200cm随海拔高度的上升而下降,最高海拔(1008m)麦田0~100、100~200cm土层及其他3个海拔麦田不同土层深度在不同生育阶段土壤耗水量与其初始土壤贮水量均呈正相关;不同海拔麦田的全生育期平均气温与其全生育期不同土层的土壤耗水量均呈现正相关;水分利用效率基本随海拔高度的升高在提高。

Four wheat fields with different altitudes in the southern Shanxi Province from 2017 to 2018 were selected for studying soil water change characteristics and water use efficiency.As the results revealed,the soil storage water at different depths in wheat fields with different altitudes during maturity stage was lower than that during sowing stage.The proportion of soil storage water at 0-100 cm,100-200 cm and 0-200 cm depth in the wheat fields with different altitudes at harvest stage to that at sowing stage ranged from 47.28%to 45.46%,42.49%to 77.50%and 45.06%to 60.96%,respectively,and the ratio at 0-200 cm and 100-200 cm depths increased with the increase of altitude.The ratio of soil consumption water at 0-100 cm and 100-200 cm depths from the sowing stage to the maturity stage to that at 0-200 cm was 51.53%-72.12%and 27.88%-48.47%,respectively,and the ratio of that at 0-100 cm depth increased with the increase of altitude,but the ratio at 100-200 cm depth was opposite.The proportion of soil consumption water at 0-100 cm,100-200 cm and 0-200 cm depth from sowing stage to maturity stage to that at the same depth during the sowing period was 52.72%-54.54%,22.50%-57.51%and 39.04%-54.94%,respectively,and the ratio at 100-200 cm and 0-200 cm depths decreased with the increase of altitude.The soil consumption water at 0-100 cm and 100-200 cm depths in the wheat fields with altitude of 1008 m and the other three different altitudinal wheat fields at different depths and different growing stages presented a positive correlation with the initial soil storage water.Moreover,the mean temperature was positively correlated with soil consumption water at different depths during the whole growth period,and water use efficiency increased with the rise of altitude.