Challenges to the Arctic Environment and Biodiversity

Transcription

1 Challenges to the Arctic Environment and Biodiversity Rolf Anker Ims Department of Arctic and Marine Biology University of Tromsø & Terrestrial Flagship Program FramCentre Foto. Geir Vie

2 Contents 1. Properties: Arctic environments & biodiversity 2. Challenges I: Drivers of change and their impacts 3. Challenges II: Science and management

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4 1. Properties of Arctic environments & biodiversity Physical properties Cold climates Long seasons with snow and ice Large tracks of relatively pristine landscapes

5 Biological properties Arctic species are adapted to cold, snow & ice -> low resilience to other challenges Short seasons for biological production Simple ecosystems Single species has keystone functions -> ecosystem integrity/overall biodiversity -> ecosystem services Still relatively intact ecosystems

6 2. Challenges/Threats: Drivers of change The Key Challenge: Climate warming The heat is already on

7 Marine Impacts: Reduced sea ice extents (Stroeve et al. 2012)

8 Terrestrial impacts: Tundra ecosystems Longer vegetation growth season (Xu et al. 2013): Southern seasons has moved 4-7 latitudinal degrees north over the last 30 years

9 Greening of the terrestrial Arctic: Evidence from remote sensing (Beck & Goetz 2011) Trends

10 Arctic greening : Evidence on ground (Elmendorf et al. 2012). - Encroachment of shrubs and trees into open tundra - A negative impact 1. Loss of habitat for arctic biodiversity

11 Encroachment shrubs and trees into open tundra: More spontaneous climate gas emissions Sturm et al Swann et al ; Hartley et al H 2 O CO 2

12 Encroachment of shrubs and trees into open tundra: Reduced albedo more absorbed heat Chapin et al

13 Terrestrial impacts: Changed winter climate More rain-on-snow-events (Putkonen & Roe 2003) In Svalbard: Drives animal crash-boom dynamics (Stien et al Hansen et al )

14 In high-arctic Greenland: Collapse in lemmings and snowy owls (Schmidt et al. 2012). - 98% reduction

15 Terrestrial climate impacts: Southern margins of the Arctic Outbreaks of new pest organisms During : 1/3 forest-tundra of N Norway devasted 100 km

16 Climate impacts on ecosystems & biodiversity: - We are only starting to see the beginning! Model projections year 2100 : +2-8 o C Projected vegetation growth season (Xu et al ): Southern growth seasons to move > 20 latitudinal degrees north 78 o N, o N, 1980

17 Challenges: Science and the management in face of the vast & fast changes 1. Science of arctic ecosystems and biodiversity - unable to predict the outcomes - We are outside our empirical range no historical analogues - Ecological models : predictive ability for equilibrium systems lack predictive non-equilibrium systems

18 Challenges: Science and the management in face of the vast & fast changes 1. Science of arctic ecosystems and biodiversity - unable to predict the outcomes - New & disturbed ecosystems with unknown properties - Climate change will come together with: -New human infrastructure -New & more industries in the Arctic -Pollution Cumulative impacts: Notoriously difficult to predict!

19 Challenges: Science and the management in face of the vast & fast changes 2. The science of arctic ecosystems and biodiversity needs to change approach - More Accurate and in-depth real time observations rather than on model projections - More Long-term continuity rather than short-term programs

20 Challenges: Science and the management in face of the vast & fast changes 2. The science of arctic ecosystems and biodiversity needs to change approach - More Holistic & ecosystem-based than Fragmented & indicator-based - Improved partnerships: Scientists and managers/policy makers Scientists and stakeholders

21 Challenges: Science and management 3. Active conservation/management actions within the arctic - may be needed & possible Example: Ecological engineering Rational management of large herbivores & live-stocks can counteract the encroachments of tall shrubs in tundra (Post and Pedersen Olofsson et al. 2009)

22 Challenges: Science and management Example: The endangered arctic fox in mainland Scandinavia Species conservations by actions Ecample: The arctic fox Critically endangered in mainland Fennoscandia Action Action Such conservation actions come at certain costs - Norwegian authorities spend ~8 mill NOK per year Angerbjörn et al J Appl Ecol on research and management on the Arctic fox

23 Continuous & Long-term State-of-the-art science Ecosystem-based Management oriented Stakeholder involvements