Research

We study how biodiversity is connected to ecosystem functions, such as nutrient cycling, carbon uptake and biomass production. Species interactions, such as herbivory, plant-microbe interactions and competition are in the core of our research: we study their roles in biodiversity-ecosystem functioning relationship. As methods we use field and mesocosm experiments and long-term data analyses.
Functional ecology

Changes in biodiversity and ecosystem functioning emerge from species responses to environment and each other. To predict these changes, we describe plant communities based on species' characteristics, which are related to their performance, so called functional traits. These traits, for example plant's nitrogen requirement or root length, can reflect its responses to environment and other species, and their contribution to ecosystem functions.
In search for mechanisms

Does functional diversity drive ecosystem functioning and stability? We test hypothesis of mechanisms linking functional diversity to ecosystem functioning using mesocosms. Viikki Plant Growth Facilities offer flexible and easily accessible space for our greenhouse experiments just behind our office building.
Deer and biodiversity of boreal forest

White-tailed and roe deer populations have grown rapidly during past decades in Finland. Still, we know little of their importance for forest understory and tree diversity. We use two approaches to investigate the role or deer:

  1. a distributed exclosure experiment focuses on impacts of grazing in local plant communities from clearcuts to old forests
  2. analyses of long-term monitoring datasets offers a wider outlook to biodiversity changes over space and time

This research is collaboration with Natural Resources Institute Finland (Luke).
Herbivory in a warming tundra

Climate warming changes tundra plant communities via two main mechanisms: by altering performance of the local species and by enabling lowland and southern species immigration to open tundra. However, these mechanisms are not only driven by temperature, but their outcome depends on other abiotic factors and biotic interactions in the system.

Since 2009, we investigate how herbivores and nutrient availability modulate effects of climate warming using a field experiment in an open tundra meadow in Kilpisjärvi, NW Finland. The main herbivores in the area are semi-domesticated reindeer, voles, lemmings, and mountain hares. Kilpisjärvi Biological Station enables this research by offering laboratory facilities, accommodation and research support. This is collaboration with Prof. Anu Eskelinen, University of Oulu.
TExNet - Herbivore diversity in tundra

Tundra Exclosure Network (TExNet), is a collaborative research network that studies the impact of vertebrate herbivore diversity on tundra ecosystem properties and functions by means of a coordinated multi-site field experiment.

We use varying mesh sizes to exclude different sizes of herbivores from experimental plots to study their impact on plant communities and ecosystem functions. One of the experimental sites is in Kilpisjärvi, where the Biological Station serves as a base camp for our field campaigns.

This collaboration with many tundra ecologists is led by Elina Kaarlejärvi and Prof. Isabel C Barrio. It has been supported by the Icelandic Centre for Research (Rannis), EU-INTERACT and UArctic.