Wetlands in warm ecoregions

– Indicators for Climate Change Impacts –

Interactions between Climate Change, other stressors and the biota are complex. What are the main impacts? Which simple parameters are suited to detect them?

Here we suggest indicators, which reflect the main effects of Climate Change on freshwater ecosystems.

Within the Euro-Limpacs consortium there is an ongoing discussion about the best suited indicators. On this page you find a first selection, which will frequently be updated and improved within 2008.

• Biological parameters

  • Bird migration

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Temperature
    Responding parameter group	Biological parameters
    Responding parameter	Bird migration

    Response description

    Spring migrations start earlier with warming. This is more pronounced early in the season, and with terrestrial and wetland birds than with waterfowl.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Beginning of spring migration period

    Reference(s)

    Zalakevicius M. & R. Zalakeviciute (2001): Global climate change impact on birds: a review of research in Lithuania. Folia Zoologica 50(1): 1-17.

  • Ecosystem maintenance

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Temperature
    Responding parameter group	Biological parameters
    Responding parameter	Ecosystem maintenance

    Response description

    Ecosystems potentially will suffer if detritus and species are lost to severe flooding and runoff events, and if drought levels exceed the tolerance limits of species.

    Specification of relevant ecosystem type

     Riverine wetlands

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Frequency and severity of storms

    Justification of indicator

    Reduction of biomass and species due to wash out.

    Suggested indicator 2

    Soil/sediment moisture content

    Justification of indicator 2

    Tolerance of species to drought may lead to extinctions, leaving the system open to invasions by exotic species

  • Food web support I

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Temperature
    Responding parameter group	Biological parameters
    Responding parameter	Food web support I

    Response description

    Plant production supports production by other plants and various species of animal, either directly through food chains or indirectly via consumer organisms. Increased temperature may influence primary production and water availability, thus having consequential impacts across the ecosystem.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Air temperature

    Justification of indicator

    Increased temperature may result in increased rates of primary production.

    Suggested indicator 2

    Height of water table

    Justification of indicator 2

    Adequate water availability enhances primary production

  • Food web support II

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Temperature
    Responding parameter group	Biological parameters
    Responding parameter	Food web support II

    Response description

    Drought and flooding both contribute to mineralisation and release of nutrients from organic matter. This can increase the build up of plant-available nutrients in the sediments, which are readily washed into water courses and wetlands in runoff.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Frequency and severity of storms

    Justification of indicator

    Increase in eutrophication may result from large runoff events.

    Suggested indicator 2

    Height of water table

    Justification of indicator 2

    Desiccation may lead to oxidation and mineralisation of bound nutrients, which can then wash into water bodies and wetlands in runoff

  • Insect species

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Temperature
    Responding parameter group	Biological parameters
    Responding parameter	Insect species

    Response description

    Changing climate has direct effects on the distributions of both terrestrial and aquatic insect species. Milder winters and hot summers are important factors in the survival of temperature-sensitive species. This will probably alter the tolerable ranges of some species, including pest species, and may lead to increased invasions into new areas by exotic species.

    Secondary effects

    Probable increased impacts on agriculture and biodiversity

    Specification of relevant ecosystem type

    Wetlands and open water

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Taxonomic composition and abundance of insect species, especially butterflies and aquatic insects

    Justification of indicator

    Indicates impacts on habitat integrity.

    Reference(s)

    Thomas J.A. (2005): Monitoring change in the abundance and distribution of insects using butterflies and other indicator groups. Philosophical Transactions of the Royal Society B-Biological Sciences 360(1454): 339-357.

• Hydromorphological parameters

  • Flood water retention

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Hydrology
    Responding parameter group	Hydromorphological parameters
    Responding parameter	Flood water retention

    Response description

    Increased temperature may lead to increased rates of evaporation.

    Secondary effects

    Reduced mean rates of runoff.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Height of water table

    Justification of indicator

    Retention of flood water will be enhanced if the water table is lowered but reduced if the water table is higher.

  • Groundwater recharge

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Hydrology
    Responding parameter group	Hydromorphological parameters
    Responding parameter	Groundwater recharge

    Response description

    Ability to recharge aquifers is affected by desiccation.

    Secondary effects

     Discharge of groundwater is likely to be reduced where drought occurs or abstractions are increased.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Height of water table

    Justification of indicator

    If the water table is high, the rate of recharge of groundwater (if any) will be increased.

  • Sediment retention

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Temperature
    Responding parameter group	Hydromorphological parameters
    Responding parameter	Sediment retention

    Response description

    Scouring of sediments by extreme weather events.

    Secondary effects

    Oxidation of sediments due to desiccation can lead to loss of sediments.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Frequency and severity of storms

    Justification of indicator

    Storms and associated flash floods and spates may wash away sediments and detritus, reducing their retention.

• Physico-chemical parameters

  • Carbon retention

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Temperature
    Responding parameter group	Physico-chemical parameters
    Responding parameter	Carbon retention

    Response description

    Retention of carbonaceous material will be enhanced if warmer temperatures increase primary production while water availability is sufficient, but will be reduced if runoff events increase in frequency.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Rate of primary production

    Justification of indicator

    Retention of carbon in vegetation and detritus will be enhanced by increased production.

    Suggested indicator 2

    Runoff

    Justification of indicator 2

    Increased runoff will reduce the conservation of organic matter

  • Nutrient export

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Hydrology
    Responding parameter group	Physico-chemical parameters
    Responding parameter	Nutrient export

    Response description

    Increased production leads to greater provision of organic detritus, which is then available for export downstream.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Production of litter

    Justification of indicator

    Export of nutrients will increase if detritus production is high.

    Suggested indicator 2

    Runoff

    Justification of indicator 2

    High rates of runoff will facilitate the export of nutrients

  • Nutrient retention

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Temperature
    Responding parameter group	Physico-chemical parameters
    Responding parameter	Nutrient retention

    Response description

    Longer season and warmer temperatures can lead to increased primary production.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Rate of primary production

    Justification of indicator

    Retention of nutrients is potentially greater where production is high.

    Suggested indicator 2

    Oxidation rate

    Justification of indicator 2

    High rates of oxidation and mineralisation can liberate nutrients, and reduce their retention in the wetland

  • Organic carbon export

    Climate Region	Warm
    Ecosystem type	Wetlands
    Stressor type	Hydrology
    Responding parameter group	Physico-chemical parameters
    Responding parameter	Organic carbon export

    Response description

    Organic carbon is provided for downstream ecosystems in runoff water.

    Relevant ecoregion(s) according to Illies

    All warm ecoregions

    Suggested indicator

    Height of water table

    Justification of indicator

    Organic carbon can be released as dissolved organic carbon (DOC) in runoff water.

    Suggested indicator 2

    Incidence of storms

    Justification of indicator 2

    Increased runoff will increase the export of organic matter