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Species and communities in streams and wetlands

Species and communities in streams and riparian areas (e.g. wetlands) are fundamentally influenced by human activities. Our research aims to investigate the impact of these activities at organism, population and ecosystem level, as well as to predict the consequences of their changes. We are also trying to uncover the importance of both local stream characteristics and regional factors at several spatial and time scales for the biodiversity of water, community structure and the composition of the characteristics of species and food chains.

We have a special focus on examining (i) the importance of land-water interactions for the organisms and biodiversity of the streams and wetlands, (ii) separating the effects of individual stress factors (e.g. sediment transport or nutrient enrichment) under conditions of simultaneous occurrence of multiple stress factors, as well as (iii) understanding how the interactions of organisms and organism groups are affected by relevant stress factors.

Ongoing projects within this topic

Maximizing ecosystem services provided by riparian BUFFERs using novel TECHnologies (BUFFERTECH)

BUFFERTECH
2014-2018. Optimising ecosystem services from buffer zones using new technological methods. The project examines how we can optimise ecosystem services such as buffer zones (nature, environment and production) by placing them in a differentiated and cost-effective way in the landscape using new and innovative management methods and technological solutions. The project is financed by the Danish Council for Strategic Research.

Water resources management under complex, multi-stressor conditions (MARS)

MARS
2014-2018. MARS has a particular focus on examining the overall effects of low water flow, nutrients and fine sediments on the biological structure and function. In our experiments, we investigate the influence of these stressors on the community structure of macroinvertebrates, phytobenthos and freshwater fungi and the interactions between these groups of organisms under the given stress scenarios. In addition, we examine how the ability of organisms to perform their ecological function is affected in these stress scenarios (e.g. metabolism, nutrient uptake and decomposition of organic matter). The project is financed by the Lundbeck Foundation.

Danish Stream Plant Index (DVPI) in small streams

2018. As a starting point, the ecological status of steams is assessed in accordance with the EU Water Framework Directive based on the biological quality elements macrophytes, macroinvertebrates, fish and phytobenthos. So far, DVPI is only used in medium-sized and large streams. The purpose of this project is to develop an adjusted version of the existing Danish Stream Plant Index (DVPI) for use in Type 1 streams. This includes setting threshold values between the ecological status classes so that they reflect the same level of protection as the existing DVPI. The project is financed by the Danish Environmental Protection Agency.

Restoring biodiversity in streams: Strategy and method selection

Strategy and method selection
2017-2020. This project evaluates the effects of restoration measures in streams, partly through existing data and partly through the collection of new data in field studies. The main focus of the project is rare species and species in decline, examining the extent to which current restoration methods create the necessary habitats for the rare species and the extent to which a successful re-migration is taking place in the restored stretches. The field work includes release of rare species in selected streams and follow-up on their survival after release. The project is financed by the Aage V. Jensen Foundation.

Validation and intercalibration of DNA metabarcoding for routine use in Fenno-Scandinavian invertebrate biomonitoring (SCAN-DNAnet)

2018-2019. The project aims to explore the possibilities of using DNA from macroinvertebrates for routine DVFI monitoring under the Water Framework Directive. Knowledge of DNA for monitoring is sparse, and therefore the project will generate knowledge which in the longer term can be useful to the authorities in the monitoring of streams. The project is carried out in collaboration with researchers from Sweden, Norway, Iceland and Finland. The project is financed by the Nordic Council of Ministers.

Benthic algae communities in small streams and effects of weed cutting

2016-2018. The project aims to describe phytobenthos communities in small streams and their impact on nutrient absorption. It includes an examination of how weed cutting affects the phytobenthos communities in Danish streams. We expect that weed cutting affects both the quantity, composition and diversity of phytobenthos and thus also the nutrient uptake. In addition, we examine whether the phytobenthos communities respond differently to pesticides at different weed cutting intensities. The project is financed by DCE (AU).

Assessment of the effects of invertebrates and benthic algae in streams

2018-2019. The project aims to assess the direct impact of water abstraction on macroinvertebrates and phytobenthos, as well as to identify threshold values for changes in the communities at different flow regimens. The project is carried out in cooperation with GEUS. The project is financed by the Danish Environmental Protection Agency.

Assessment of groundwater impact on groundwater-dependent terrestrial ecosystems and lakes

 

2018. The objective of the project is to provide a basis for assessing both the quantitative and the chemical status of groundwater bodies in terrestrial ecosystems that are directly dependent on the groundwater body as well as lakes cf. the definition of good ecological status in the Water Framework Directive. The project is carried out in collaboration with GEUS and the Section for Biodiversity (AU, Bioscience). The project is financed by the Danish Environmental Protection Agency.

Chemical effects of groundwater on streams

2017-2018. The purpose of the project is to assess the extent to which groundwater pollution has an impact on the environmental criteria for hazardous substances and heavy metals in streams. The project is carried out in cooperation with the Section for Catchment Science and Environmental Analysis (AU, Bioscience) and GEUS. The project is financed by the Danish Environmental Protection Agency.

Development of biological indices for benthic algae in Danish streams

2016-2018. The ecological status of steams is assessed in accordance with the EU Water Framework Directive based on the biological quality elements macrophytes, macroinvertebrates, fish and phytobenthos. The aim of the project is to develop an index for phytobenthos to be used for the assessment of ecological status in streams. In addition, it will be examined whether the inclusion of phytobenthos as a quality element will provide essential information about ecological status in relation to human impacts on streams. The project is funded by the Danish Environmental Protection Agency.

The effect of insecticides on the terrestrial stages of aquatic insects – an overlooked factor of importance to macroinvertebrate communities in Danish streams? (AquaTerra)

2016-2018. In this project, the sensitivity of adult stages of macroinvertebrates to pesticides is investigated through experimental work. The sensitivity data of the species is combined with mathematical risk models for exposure of riparian areas - where the majority of the macroinvertebrates are present - to pesticides via wind drift. The project is funded by the Danish Environmental Protection Agency, Pesticide Research Programme.

Importance of ecological plasticity of macrophytes for the ecological status of streams

2017-2020. Over the last 120 years, the decline of macrophytes in streams and lakes has been significant and some species are today threatened with extinction. Understanding the mechanism behind the decline is essential in order to take action to minimise further loss. This project examines the ecological plasticity of macrophytes in order to determine whether there is a link between the ecological plasticity of the species, i.e. how well they perform under multiple stressors, and their current distribution. In controlled experiments, ecological plasticity is quantified for selected species along resource gradients. The project is financed by DCE and GSST (AU).