Why do trees adjust water relations and hydraulic architecture in response to nutrient availability?

Abstract

Studies on water relations, hydraulic architecture and effects of nutrients on growth in trees have been studied for many years in relative isolation. Only recently the functional relations of these groups of plant traits have been investigated with a more integrative approach (e.g. Harvey and van den Driessche, 1999; Clearwater and Meinzer 2001: Ewers et al. 2000, 2001; Bucci et al. 2006; Hacke et al. 2010; Faustino et al. 2013). In this commentary we attempt to answer the question of why water relations and the hydraulic architecture of trees are functionally related with their nutrient availability. We will focus on results of studies where nutrient limitations have been removed or alleviated by additions of the two most important macronutrients: nitrogen and phosphorous.