Research

What is Functional Biodiversity Research?

Typical questions of our working group:

  • Why are more diverse grasslands more productive than less diverse ones?
  • What is more important for wood decomposition: environmental settings or species traits?
  • Are hyperdiverse plant communities functionally better?
  • Why does the boreal forest in Sibiria burn twice as often as the one in Canada?
  • How fast can plant species react to climate change?

Functional biodiversity research is an interdiciplinary synthesis of special botany, plant ecology, vegetation ecology and ecosystem sciences. It integrates over theories and methods from all these research areas, combining them with some distinctive features. It developed in the 1990ies to study the ecological consequences of global species loss and gradual changes in species distributions. As it is a relatively new research area, we here specify the position of functional biodiversity research in the realm of the older, more classical disciplines.

Biodiversity

Biodiversity denotes the variety of biological species, their genetic configuration as well as the variability of community compositions. In this spirit, biodiversity per se has been studied for centuries. In plant sciences this was primarily done by systematic research within the field of special botany, the science of plant species, and within geobotany. To sort the diversity, taxonomists initially concentrated on those morphological and anatomical traits which enabled them to differentiate between species and shed light on phylogenetic relationships. Nowadays, this naturally includes metabolomic and genetic traits as well.

Functional Biodiversity research, however, concentrates on those plant traits that are functionally important - both for the "functioning" of the organism itself (autecological view) and for the ecosystem it lives in (ecosystematic view).

The autecological branch systematically compares functional traits. This is a large endeavor which has only just begun. The focus is on plant species in their diversity, which is why the area of special botany plays a central role in its research and teaching. The patterns emerging when looking at functional traits of many species together, may explain some profound principles of the functioning of plants such as:

  • the fundamental tradeoffs, e.g.the evolutionary or physically possible combinations of functional traits,
  • the grouping of plant species to functional types,
  • the relationship between trait configuration on the one hand and abiotic and biotic environment as well as disturbance on the other hand,
  • the phylogenetic and historic conditionality of the local and regional spectra of functional traits,
  • the plastic constraints and evolutionary speed of functional traits.

The methods include (i) the measurement of functional traits of plant species, (ii) the acquisition of already published trait data and their covariates in the systematic-phylogenetic context in extensive, relational data bases as well as (iii) the interspecific analysis of trait data using modern statistics (multivariate analysis, hierarchical bayes).

Ecosystem

The ecosystematic branch of functional biodiversity research, studies the effects of these traits on ecosystem functioning and -services. Here both, the presence of a single species (and its species specific traits) or the diversity of species (and thus trait diversity or functional diversity) can play an important role. Therefore, effects of species identity and species diversity are differentiated. Both effects and their relationships to ecosystem functioning are studied using empirical and model based methods. Empirical methods can use field studies or experiments. Field studies look at ecosystem functioning along gradients of species diversity or -identity in natural or near natural ecosystems (e.g. comparison of different plant regions with diverging species configuration). Experiments deliberately construct such gradients as found e.g. in the Jena Experiment or the BEF China project. The goal here is to test hypotheses about the relationship between plant species richness and ecosystem functioning. To understand the underlying mechanisms, however, these relationships are often reconstructed with ecosystem models. Ecosystem models are generally able to convert species trait information into ecosystem performance. The forecasts of these models can be confronted with reality to differentiate between hypotheses or to generate new hypotheses.

There are important interactions with climate change and landuse changes. These factors effect both vegetation structure (and thus functional identity and -diversity) and ecosystem processes and -services directly. Climate affects vegetation structure by changing the intraspecific interplay of demographic processes (e.g. seed production, seedling establishment, mortality). This happens either directly through species specific differences in climate sensitivity or indirect via climate induced changes in disturbance regimes. Populationbiology and vegetation ecology are hence also important in functional biodiversity research.

last modified: 04.11.2016