Radial growth response of Hedera helix to hydrological changes and climatic variability in the Rhine floodplain

Abstract

AbstractThis paper presents a dendrochronological study of Common Ivy in alluvial environment. Our objective was to analyse the response of ivy plants to hydrological and climatic variations. The study was carried out in three forests: Rhinau, which is regularly flooded; Erstein, where floods were eliminated with the canalization of the Rhine River in 1967 and Heiteren, an upland forest. Multivariate models performed for each forest showed that the response of ivy to temperature, precipitation and water table level depended on the hydrological history of the site. In the flooded forest of Rhinau, ground water depth in June and July, that is at the time when floods usually occur, was one of the main factors stimulating growth while in Erstein, rises of the ground water levels stimulated growth only when they occurred in winter, that is when the water table is normally the lowest in the year. In the driest forest of Heiteren, growth was stimulated by hot summer temperatures coupled with rainfall from May to July. In the two riparian forests ivy displayed a positive response to increasing temperatures in February and March. The ability to take advantage of early temperature increases may be a particularly important aspect of ivy ecology in deciduous forests. Copyright © 2008 John Wiley & Sons, Ltd.