TREELANDS – Trees as Islands – on the phylogenetic isolation of trees in mixed forests

点击翻译按钮获取中文摘要

Mixing trees in production forests is one of the core tools of silvicultural forest management. In the Biodiversity Exploratories the increasing proportion of conifers is a major determinant of the land-use intensity in the forests. However, the ecological mechanisms driving the diversity in the canopy of trees embedded in different evolutionary neighbourhoods is still poorly understood. The neighbourhood to tree species with an increasing evolutionary distance as the phylogenetic isolation can affect the target tree and it inhabitants in many ways: first by changing the crown and leaf characteristic, second via isolation from neighbour with increasing distance. Here we test the hypothesis that phylogenetic isolation of a host tree affects the arthropod communities for the four major tree species in Central Europe, Fagus sylvatica, Quercus petrae, Pinus sylvestris and Picea abies. We will combine canopy arthropod fogging samples, Terrestrial Laserscanning, microclimate measurements, Leaf measurements and innovative barcoding methods to test eight predictions in four research fields. First, we will investigate if phylogenetic isolation affects insect communities directly via isolation or indirectly by changes in crown structures. Second we will study the effects of phylogenetic isolation on within tree variation and third the effects of this variation on insect communities. Fourth, we will study the effect of phylogenetic isolation on herbivory, diversity of different guilds and within species variation. This will allow us to test for the first time how far previous results from oaks can be generalised to other tree species and give a deeper insight into the ecological mechanisms behind the mixing component of the land use gradient in forests.