降雨量对大针茅水分利用效率的影响

Effects of precipitations on water use efficiency of Stipa grandis

借助1983—1993年间收集的历史样品,并通过移栽和浇水试验,研究纯粹的降水因子对大针茅水分利用效率的影响.结果表明,无论是在时间尺度还是移栽实验中,降雨量对大针茅的水分利用效率影响显著.并且仅仅降雨量的变化就能够造成人们在空间尺度上观察到的响应格局,这种格局是否受遗传因素的影响还需要进一步研究.

The pattern that water use efficiency （WUS） decreased with precipitation is shown in spatical scale and it may be affected by both the genetic and environmental factors. Samples of Stipa grandis, collected at the same site during a period from 1983 to 1993 and common garden experiments, were used to study the relationship between the precipitation and WUE. The results show that WUE strongly decreases with precipitation in both the two experiments and that only the change in precipitation causes this pattern. The genetic effect needs further investigation.