Root traits are related to plant water-use among rangeland Mediterranean species

1. Understanding the water-use of plants is timely under increasing drought stress due to climate change. Despite the crucial role of roots in water uptake, relationships between water-use and root traits are seldom considered. 2. Combining a functional traits-based approach with a water balance model, we tested whether root functional traits are related to spatial and temporal water-use among 12 Mediterranean rangeland species grown in common garden monocultures. Soil water content was monitored for 10 months, and the dynamics of water uptake of each species was modelled at a daily time step. Root functional traits were measured at two soil depths (shallow and deep soil). 3. Species with fast resource acquisition strategies in shallow soil, i.e. thin roots, maximised water uptake in a short period and consumed large amounts of water during periods of low water availability. Conversely, species with a more conservative root strategy, i.e. coarse roots, took up less water during the peak...

1. 在气候变化导致干旱胁迫日益加剧的背景下，解析植物的水分利用规律恰逢其时。尽管根系在水分吸收过程中发挥着关键作用，但水分利用与根系性状之间的关联却鲜有研究涉及。2. 本研究将基于功能性状（functional traits）的研究方法与水分平衡模型（water balance model）相结合，针对12种在同质种植园中单作栽培的地中海放牧草地植物，探究根系功能性状与水分利用的时空特征之间的关联。研究对土壤含水量进行了为期10个月的连续监测，并以日时间步长对各物种的水分吸收动态进行建模。同时在两个土壤深度（浅层与深层土壤）下测定了根系功能性状。3. 在浅层土壤中采用快速资源获取策略的物种（即拥有细根），可在短时间内实现水分吸收最大化，并在水分有效性较低的时段消耗大量水分。与之相反，采用更为保守的根系策略的物种（即拥有粗根），在水分峰值期的水分吸收量则相对较少……