Questions of importance to the conservation of global biological diversity

Transcription

1 Questions of importance to the conservation of global biological diversity Answers from the past Kathy Willis, Shonil Bhagwat, Angelica Feurdean, Cindy Froyd

2 Long-term Ecology Lab

3 Conservation Biology Conservation biology has developed into a science of documenting population declines, species losses and habitat destruction in excruciating detail but sadly doing little about it. T. Caro, 2007, TREE, 22,

4 Sutherland et al One hundred questions of importance to the conservation of global biological diversity Ecosystem function and services Climate change Technological change Protected areas Ecosystem management and restoration Terrestrial ecosystems Marine ecosystems Freshwater ecosystems Species management Organisational systems and processes Societal context and change Impacts of conservation interventions

5 Answers from the past A Time Machine Baselines Change Complexity Dynamism Recovery Resilience Thresholds Variability

6 Yes, we can! Palaeoecology can: make a substantial contribution to the conservation of global biological diversity unravel the processes behind patterns provide insights into management But we must make our data more accessible to conservation biologists

7 Case-studies 1. Determination of baselines and natural ecosystem variability 5. Conservation and culture 3. Species migration in response to climate change 6. Tropical forest recovery and management 4. Biological invasions 2. Ecological thresholds and resilience See Froyd C.A and K..J. Willis (2008) Quaternary Science Reviews, 27,

8 1. Baselines and natural ecosystem variability Baseline is the ecosystem present before human influence became pronounced on the landscape (Lindbladh et al. 2007) Pine forests of Sierra de Manantlan, Mexico, considered anthropogenic Climate or culture? B. Figueroa-Rangel, K.J. Willis & M. Olvera-Vargas (2008) Ecology, 87,

9 Pine forests of Sierra de Manantlan, Mexico Decrease in pine Increase in cloud-forest taxa High humidity cal. yr BP

10 Cyclical peaks at 80-year intervals Climatic oscillations (50-80 yr) apparent in a number of lake sedimentary records from Mexico (e.g. Hodell et al. 2001, Science, 292, 1367) Thought to be linked to solar forcing resulting in drought-cycles at approximately this time interval Pine forest natural baseline?

11 2. Ecological thresholds and Camoin et al Camoin et al Battistini 1976 resilience Ecological threshold is the point at which there is an abrupt change in an ecosystem quality, property or phenomenon Ecological resilience is the ability of systems to absorb disturbance and still maintain the same relationships between populations or state variables (Holling 1973) M. Virah-Sawmy, L. Gillson and K.J. Willis (2008) GEB, 18,

12 Resilience of Madagascar s littoral forests Erica matrix Littoral forest Marine surge + Drought = Threshold Event

13 Lessons for adaptation to climate change? Littoral forest more resilient than Erica matrix Sea-warer influx counteracted by soil Deep water intake by roots Connected canopies as shields Climate changeintegrated conservation

14 3. Species migration in response to climate change Climate change might force species out of their ranges Species will need to migrate in response Understanding of how quickly species can migrate is important Bhagwat S. A. and K.J. Willis (2008) J. Biogeography, 35:

15 Glacial history of Europe Ice sheet Northerly glacial refugia Mediterranean refugia Source: Willis et al (in press)

16 Migration rates of European trees Trees Fir Alder Birch Hornbeam Beech Spruce Pine Oak Willow Hazel Poplar Over- estimate (%) Species modellers beware!

17 4. Biological invasions J. Van Leeuwen, C. A. Froyd, W. van der Knaap, E. Coffey, A. Tye, K.J. Willis 2008, Science, 322:1206 What are the triggering mechanisms for biological invasions? How quickly do biological invasions occur? When is an invasive not an invasive?

18 Spread of Quinine in the Galapagos Santa Cruz Highlands 12,000 ha of Quinine

19 When is an invasive not an invasive? First humans to arrive on the island in AD1535 Introduced Doubtful native

20 5. Conservation and culture L. Nascimento, K.J. Willis, J. M. Fernandez-Palacios, C. Criado & R. J. Whittaker, (2009) Journal of Biogeography 36: The Canary Islands are a biodiversity hotspot The islands are rich in endemics and have a variety of forest types What impact did past human activities have on development of the vegetation types?

21 Vegetation formations of La Laguna

22 To restore or not to restore? Quercus and Carpinus, thought never to have existed in the Canary Islands, went locally extinct ~ 2000 years ago Several endemics appear to co-incide with first arrival of humans Classification of Quercus canariensis always thought to be a mistake - might not be! Cultural landscapes?

23 6. Tropical forest recovery

24 Evidence of forest succession AD Charcoal Grass Open forest taxa Closed forest taxa Magnetic susceptibility 1100AD 1900AD

25 From fallow to forest in 200 years 200 years Until 1300 AD AD 1500 AD onwards AD

26 Pristine rainforest? Willis et al. (2004) Science 304,

27 Agroforestry systems Bhagwat, S.A., Willis, K.J., Birks, H.J.B. and Whittaker, R.J. (2008) Agroforestry: A refuge for tropical biodiversity? Trends in Ecology & Evolution, 23(5):

28 Making palaeoecological data more accessible See Binney H. A. et al. (2009) QSR, in press, doi: /j.quascirev

29 Making palaecological data more accessible

30 Conclusions Palaeoecology can provide answers to questions of importance to conservation of global biological diversity Long-term understanding of ecosystems provides insight into processes behind patterns Such insight directly inform conservation management of biological diversity