Jordan Guiz



Université Catholique de Louvain (UCL)

Earth and Life Institute (ELI)

Environmental Sciences (ELIE)

Croix du Sud 2 bte L7.05.09

1348 Louvain-la-Neuve

+32 (0)10 47 37 02


Research project

Nutritional interactions in mixed forest: occurrence and mechanisms

Is the nutrition of oak (Quercus sp.) and beech (Fagus sylvatica L.) on acid soils affected by the neighbourhood composition in mature mixed forests?

The aim of the study is the specification of the factors that drive the diversity of nutritional responses in mixed forests in order to predict the impact of tree species mixture on the mineral nutrition of the species involved. The four specific objectives of the study are

(1) identification of site and tree species composition conditions that modify, in comparison with pure forests, the mineral nutrition of two broadleaved species with high trophic amplitude and contrasted shade tolerance: oak (Quercus sp.) and beech (Fagus sylvatica L.)

(2) characterization, on poor soils, of the diversity of mineral-resource-use strategies of tree species that differ in their ecological needs and successional positions

(3) link those strategies to a larger set of traits that define the species' successional niche

(4) predict, based on the relevant traits, which mixtures will lead to a better mineral nutrition


The research is organized in two work packages.

(1) Combined influence of site and tree neighbourhood on its nutrition

At several sites, the correlation between the tree species composition of a target tree's neighbourhood and selected nutritional variables for the target tree will be investigated. Two nutritional variables will be studied: leaf nutrient content and nutrient accumulation on resins placed at the interface of mineral and holorganic soil horizons.

(2) Mineral resource-use by contrasted species and associated traits

For a range of tree species associated with the various successional stages on mesic acid soils in western Central Europe, functional indicators will be characterized, i.e., nutrient use efficiency, resorption efficiency, and internal nutrient distribution. Values for these indicators will be derived from literature and field measurements on individual trees. In addition, complementary traits and indicators will be collected from literature, and a relationship between these literature data and the three functional indicators will be investigated. The focus lies on nitrogen and phosphorus, two major determinants of productivity.