Characteristics of water use under the recovery from prolonged drought in invasive species in the island ecosystem.

研究了博宁岛入侵物种在持续干旱和灌溉后血管水分分布和液流速度的变化。利用主成分分析，对生长在岛屿中、旱地的几种树种的木材解剖参数和功能类型之间的关系进行了测试。入侵农田的水蚤对突发性供水的利用效果不明显。突发性降水条件下，入侵旱地的牛蹄草对水分的利用效率高于本地种。木质部导管和射线间的网络结构是决定这些树种水分利用特性的因素之一。

The changes in water distribution of vessels and sap flow velocity under continuous drought and following irrigation were examined in the invasive species in the Bonin Island. The relationships between wood anatomical parameters and functional types were also tested using analysis of principal component in several species which grow in the mesic or xeric site in the islands. Water use in Bischofia javanica, which invade mesic site, was not effective to sudden water supply. In contrast, Psidium cattleianum, which invade xeric site, could use water more effective than indigenous species in sudden precipitation. The construction of network across xylem conduits and rays is one of the contributing factor to determine the traits of water use of these species.