2017 EEA report “Climate change adaptation and disaster risk reduction in Europe - Synergies for the knowledge base and

policies”

Rob Swart, Koen Kramer, Mart-Jan Schelhaas 9 February 2016

Impacts and risks for ecosystems

Impacts and risks for ecosystems

Floods

Storms

Forest fires

Droughts/heatwaves

Floods, some initial ideas• Water retention areas along major rivers

are often forested areas rather than agricultural areas.

• Flooding can benefit riparian forests• But often the trees are not adapted to such

conditions leading to mortality and sensitivity to biotic agents, especially fungi.

• There is therefore much protest by forest managers to use their forests as water retention area.

• However, forest can play this role from a DRR point of view!

Storms: initial ideas (past)

Increase in damage in forests over the last century due to increase in forest area, planting more vulnerable species (conifers) and more timber per ha

Climate change seems to play a role, but storminess shows considerable decadal fluctuations

Impacts on biodiversity (positive and negative), but mainly socio-economic impacts (timber prices, disruption of management planning), also on protective function

Follow-up damage by pest insects can be as large as the storm impact itself

Storm damage will increase, because forest area and timber stocks are still increasing

Climate change plays a role directly (storminess) and indirectly (wetter soils, less frozen soils, taller trees in warmer climate)

Combined future negative impact of fire, storms and insect damage on carbon storage can be as large as the intended positive effect of forest management (Seidl et al. 2014)

Storms: initial ideas (future)

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Other

Anthropogenic

Other biotic

Fungi

Bark beetles

Other abiotic

Snow

Wind

Storms, compared to other factors

(Seidl et al. 2014, Nature Climate Change)

past

future

Forest fires, some initial ideas• Wild fires can be an important factor in

ecosystem stability• But dependent on magnitude and frequency

can also have many implications for biological diversity, loss of habitat

• A significant source of emitted carbon, contributing to global warming

• Air pollution problems for nearby settlements

• Increased probability of further burning in subsequent years

Forest fires: regional differences Increased risk in Southern Europe due to land

abandonment (larger areas with high fuel load, no active management of the land) and expected climate change (drier, hotter)

Increased risks in Northern and Western Europe due to climate change – it can become a problemin areas where it was no problem before, leading to surprises

Droughts and heatwaves, some initial ideas

• Impact on trees is in particular by cavitation, i.e. the interruption of the water link between the roots and foliage in case of prolonged and/or extreme drought, leading to mortality and enhanced vulnerability to biotic agents.

• Positive feedback loop is possible through decrease in vegetation cooling.

• Drought in northern, i.e. boreal, areas results in lack of snow cover, which, in combination with frost, can result to tree mortality due to frost susceptibility of the roots.

General• Extreme events such as droughts, flooding and

fire (also on unaffected trees) strongly enhance susceptibility to (new) pests and diseases.

• They also enhance the invadability of ecosystems to invasive plant and animal species

• The report can include both observations and projections

• But do we also address the OPPORTUNITIES provided by ecosystems (green infrastructure) to reduce flood risk and urban heat?