毛乌素沙地油蒿(Artemisia ordosica)灌丛穿透雨量特征及影响因素

于2012年5—9月观测了毛乌素沙地油蒿(Artemisia ordosica)灌丛的穿透雨量,分析了其变化特征及影响因素。结果显示:油蒿灌丛的平均穿透雨量占降雨量百分比(Th%)为72.3%,其中有枯枝灌丛的Th%平均为69.3%,较无枯枝灌丛的75.3%低,这可能是油蒿灌丛老化后土壤水分条件变差的原因之一。油蒿灌丛下穿透雨量及其空间分布受到有无枯枝和距主干辐射距离远近的影响,且受到降雨量和风速风向等气象条件作用明显。

Characteristics and Influence Factors of Throughfall for Artemisia ordosica Shrubs in the Mu Us Sandy Land

Field experiments of throughfall for Artemisia ordosica shrubs are carried out in Mu Us sandy land from May to September 2012 to analyze the characteristics and the influence factors of the throughfall for A.ordosica shrubs. The percentage of the average throughfall in the bulk precipitation for A.ordosica shrubs is 72.3%, among which the average throughfall for the shrubs with deadwoods is 69.3% that is less than the 75.3% for the shrubs without deadwoods. One of the reasons might be that the soil moisture decreases after the aging of the A.ordosica shrubs. Amounts and space distribution of throughfall under an A.ordosica shrub are influenced by the differences of deadwoods and radiation distances. Meanwhile, meteorological factors-such as precipitation, wind speed and direction have important influences on the throughfall for A.ordosica shrubs.