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Climate changes

Terrestrial habitats such as heaths, bogs, marshes, grasslands, forests and coastlines are the places where Denmark’s nature is found in its most unaffected form. However, many of these ecosystems depend on some sort of maintenance or cultivation, e.g. grazing.

Further, they are influenced by the fact that they have to co-exist with human activities such as agriculture, industry and traffic. This has meant that nature becomes polluted with nutrients from agriculture and emissions from industry and traffic and that as the area available for nature has diminished.

In the reports from the National Focal Point for terrestrial ecology, the latest facts on the current state of Denmark’s nature are listed. You can read the published reports here (in Danish): novana.au.dk

Climate changes on plants and soil organisms. The effects are studied in different ways; in the laboratory, in the greenhouse and in the field, and cover studies ranging from the individual level to population, societal and ecosystem levels, e.g. by manipulating various factors, e.g. temperature, precipitation and CO2.

An important research topic in our section is whether, and to what extent, the evolutionary adaptation to changing climatic conditions can occur while the actual climate changes are taking place. The section has many years research experience in studying soil organisms’ ability to tolerate cold and drought stress and the underlying molecular and physiological reasons for this.

A key research question is whether plants and animals that have been living with climatic changes for generations have already adapted to this and whether they potentially will (continue to) adapt. Not all species possess the same adaptability. For this reason, we are studying whether climatic changes also lead to changes in species composition as a result of varying abilities to thrive under changing general conditions. Climate change has been shown to affect e.g. plant competition. Increased knowledge about climatic adaptation can help us e.g. to predict the future success of plants that grow in habitats that will be affected by climate change in the future. You can read more about the applied plant ecology here.

The section participates in a number of research projects, including one of the major long-term national research projects dealing with environmental effects of climate change, CLIMAITE.

Project highlights

(In Danish)

Bumblebees and pesticides

The project aims to study how pesticides affect bumblebees, both when they are exposed solely to pesticides and when they are simultaneously exposed to other negative impacts such as starvation and parasites.

In a preliminary study, we showed that bumblebees are exposed to pesticides from Danish agriculture. The amount of pesticides the bumblebees are exposed to often will not kill them, but the latest pesticide studies have shown that although the bumblebees do not die, they may be affected to an extent that is crucial to how the bee families thrive. E.g. the bees’ ability to reproduce may be affected or their behaviour may be disturbed such that they do not bring the required amounts of pollen and nectar to the nest.

In connection with the approval of pesticides, the lethal effect on honeybees within 48 hours is investigated. However, additional test methods have been proposed, including studying long-term effects on e.g. reproduction and behaviour.

In the wild, bumblebees are exposed to many stressors other than pesticides. During their peak season, bumblebees face shortages of pollen and nectar in many areas, and we also know that bumblebees often have various parasites. Both starvation and parasites may weaken the bumblebees’ resistance to other adverse effects, e.g. pesticides.

To investigate these issues we will: 

  • Study how commonly used pesticides affect the survival, reproduction and behaviour of bumblebees.
  • Study whether the effects of pesticides are enhanced if the bees are starving or suffering from parasites.
  • Employ methods that range from simple tests in the laboratory to testing entire nests outdoors in order to contribute to assessing which tests are necessary to sufficiently examine the effect of pesticides on bumblebees and other pollinators.

 

Ecomarg

Ecomarg (The effect of glyphosate and nitrogen on plant communities and the soil fauna in terrestrial biotopes at field margins) (Miljøstyrelsens program for Bekæmpelsesmiddelforskning), 2011-2014 (projektleder: Christian Damgaard).