干旱区降水格局改变的生态效应及其复杂性

Ecological Effects of the Change of Precipitation Pattern and Its Complexity in Arid Regions

全球气候变化下,降水格局变化及其生态效应研究是加强认识干旱区水分循环与荒漠植物演替和适应等的关键。综述了干旱区降水格局变化对土壤水分分布和植物生长的影响,分析了不同降水格局下前期土壤水分和养分条件、植物类型、根系分布、水分吸收模式、物候和年龄等对植物生长的影响,指出由于干旱区降水格局变异性较大以及其生态效应受多因素影响,干旱区降水格局变化的生态效应十分复杂。目前研究通常未考虑降水格局变化的季节变异以及非生长季降水的作用,这可能会导致明显的偏差或错误。因此,为更好预测干旱区降水格局变化的生态效应,必须加强降水格局增加的季节差异对植物生长的影响研究,并重视非生长季降水的作用。

With the change of global climate,researches on the variation precipitation pattern and relative ecological effects have become important issues to further understand the water cycle and the succession,as well as adaptation of desert plants in arid regions.However,knowledge about the impact of precipitation pattern change on the soil water distribution and plant growth in arid areas is limited,and key processes and mechanism need clarification.The paper reviewed the impact on soil water distribution and plant growth of precipitation pattern change in arid areas,and analyzed the impact of antecedent soil water and nutrient conditions,plant types,root distributions,water uptake patterns,phenology and age on plant growth under different precipitation patterns.The paper also pointed out that,because the significant variation of precipitation patterns and its ecological effects were influenced by multiple factors in arid areas,the ecological effects were quite complex.Therefore,in order to better predict the ecological effects of precipitation pattern change in arid areas,we must address the research on plant growth with season variation when precipitation pattern change happens,and pay attention to the effects of non-growing season precipitation.