6. Biodiversity and climate change interactions
Authors: Natasha Calderwood (CI), Robert Munroe (BirdLife) & Nicky Jenner (FFI)
Contributors: Carter Ingram (WCS)
The issues of climate change and biodiversity are interconnected, not only through climate change effects on biodiversity, but also through changes in biodiversity that affect climate change. Conserving natural terrestrial, freshwater and marine ecosystems and restoring degraded ecosystems (including their genetic and species diversity) is essential for the overall goals of the UNFCCC because ecosystems play a key role in the global carbon cycle and in adapting to climate change, while also providing a wide range of ecosystem services that are essential for human well-being and the achievement of the Millennium Development Goals. The integration of ecosystem considerations into these is vital to meet the CBD Aichi targets for 2015/2020, especially: No. 2, 5, 10, 14 and 15.
About 2,500 Gt C is stored in terrestrial ecosystems, an additional ~ 38,000 Gt C is stored in the oceans (37,000 Gt in deep oceans i.e. layers that will only feedback to atmospheric processes over very long time scales and ~ 1,000 Gt in the upper layer of oceans2) compared to approximately 750 Gt C in the atmosphere. On average ~160 Gt C cycle naturally between the biosphere (in both ocean and terrestrial ecosystems) and atmosphere. Thus small changes in ocean and terrestrial sources and sinks can have large implications for atmospheric CO2 levels. Human induced climate change caused by the accumulation of anthropogenic emissions in the atmosphere (primarily from fossil fuels and land use changes) could shift the net natural carbon cycle towards annual net emissions from terrestrial sinks, and weaken ocean sinks through temprature rises and CO2 concentrations, thus further accelerating climate change. Ecosystems provide a wide range of provisioning (e.g. food and fibre), regulating (e.g. climate change and floods), cultural (e.g. flagship species and aesthetic tourism) and supporting (e.g. soil formation) services, critical to human well-being including human health, livelihoods, nutritious food, security and social cohesion.
While ecosystems are generally more carbon dense and biologically more diverse in their natural state, the degradation of many ecosystems is significantly reducing their carbon storage and sequestration capacity, leading to increases in emissions of greenhouse gases and loss of biodiversity at the genetic, species and ecosystem level;
Climate change is a rapidly increasing stress on ecosystems and can exacerbate the effects of other stresses, including from habitat fragmentation, loss and conversion, over-exploitation, invasive alien species, and pollution.
Field study conducted in Panama concluded that biodiverse ecosystems are likely to show greater resilience to a drying climate as the presence of several drought tolerant species provides ‘biological insurance’ to counter the loss of other species (Bunker et al., 2005).
Study conducted to investigate the effects of local bushmeat hunting on the regeneration of tropical forests in the Ngotto Forest, Central African Republic. Assessed the deficit of plant recruitment due to large mammal extirpation because of hunting but concluded that more research is needed to better understand the effects of the disappearance of large seeded plants on tropical forest resilience (Vanthomme, 2010).
Glacier retreat on South Georgia and implications for the spread of rats (Cook, 2010). Abstract: “Using archival photography and satellite imagery, we have analysed the rates of advance or retreat of 103 coastal glaciers on South Georgia from the 1950s to the present. Ninety-seven percent of these glaciers have retreated over the period for which observations are available. The average rate of retreat has increased from 8 Ma-1 in the 1950s to 35 Ma-1 at present. The largest retreats have all taken place along the north-east coast, where retreat rates have increased to an average of 60 Ma-1 at present, but those on the south-west coast have also been steadily retreating since the 1950s. These data, along with environmental information about South Georgia, are included in a new Geographic Information System (GIS) of the island. By combining glacier change data with the present distribution of both endemic and invasive species we have identified areas where there is an increased risk of rat invasion to unoccupied coastal regions that are currently protected by glacial barriers. This risk has significant implications for the surrounding ecosystem, in particular depletion in numbers of important breeding populations of ground-nesting birds on the island.”
Warming in the southern Californian current system is driving seabird declines. See: BirdLife International (2008) Seabird communities are declining in the southern Californian current system. Presented as part of the BirdLife State of the world’s birds wesbite: www.biodiversityinfo.org/casestudy.php?id=97
Climate change hastens extinctions of reptiles and amphibians in Madagascar. See on www.sciencedaily.com “New research from the American Museum of Natural History provides the first detailed study showing that global warming forces species to move up tropical mountains as their habitats shift upward. Christopher Raxworthy, Associate Curator in the Department of Herpetology, predicts that at least three species of amphibians and reptiles found in Madagascar’s mountainous north could go extinct between 2050 and 2100 because of habitat loss associated with rising global temperatures. These species, currently moving upslope to compensate for habitat loss at lower and warmer altitudes, will eventually have no place to move to.”
- How can we better understand feedback effects on sinks and sources?
- What characteristics might make a species particularly vulnerable to changes in climate? (consider restricted range, endemism, niche habitat, altitudinal range etc)
- Think of examples in which climate change could interact with existing threats to exacerbate pressure on biodiversity (examples to get started might include: climate change expected to ease the rate of establishment of invasive species in the South Atlantic which will increase threats to native biodiversity; less predictable rainfall in southern Belize is reducing productivity of staple crops and leading to increased land clearance as farmers are forced to utilize larger areas to maintain the same level of production. This is increasing pressure on forest habitat etc).
- Are there examples whereby biodiversity conservation strategies might exacerbate climate change?
Bunker, D.E., DeClerck, F., Bradford, J.C., Colwell, R.K., Perfecto, I., Phillips, O.L., Sankaran, M., Naeem, S. (2005) Species loss and aboveground carbon storage in a tropical forest. Science 310 (5750), pp. 1029-1031.
Campbell, A., et al. (2009). Review of the Literature on the Links between Biodiversity and Climate Change: Impacts, Adaptation and Mitigation. Secretariat of the Convention on Biological Diversity, Montreal. Technical Series No. 42.
Chapin III, F.S., Zavaleta, E.S., Eviner, V.T., Naylor, R.L., Vitousek, P.M., Reynolds, H.L., Hooper, D.U., , Díaz, S. (2000). Consequences of changing biodiversity. Nature 405 (6783), pp. 234-242.
Cook, A.J., Poncet, S., Cooper, A.P.R., Herbert, D.J. & Christie, D. (2010) Glacier retreat on South Georgia and implications for the spread of rats. Antarctic Science, 22: 255-263.
Diaz, S., Hector, A., and Wardle, D.A. (2009)Biodiversity in forest carbon sequestration initiatives: not just a side benefit. Current Opinion in environmental Sustainability 1: 55-60.
IPCC, 2007: Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, Pachauri, R.K and Reisinger, A. (eds.)]. IPCC, Geneva, Switzerland, 104 pp.
Perring, C. (2010). Biodiversity, ecosystem services, and climate change. Environment Department Papers, World Bank Environment Department.
Pielke, R. A., Sr., Marland, G., Betts, R. A., Chase, T. N., Eastman, J. L., Niles, J. O., Niyogi, D., and Running, S.: 2002, ‘The influence of land-use change and landscape dynamics on the climate system- relevance to climate change policy beyond the radiative effect of greenhouse gases’, Phil. Trans. A 360, 1705–1719.
Thompson, I., Mackey, B., McNulty, S., Mosseler, A. (2009). Forest Resilience, Biodiversity, and Climate Change. A synthesis of the biodiversity/resilience/stability relationship in forest ecosystems. Secretariat of the Convention on Biological Diversity, Montreal. Technical Series no. 43, 67 pages.
Secretariat of the Convention on Biological Diversity (2003). Interlinkages between biological diversity and climate change. Advice on the integration of biodiversity considerations into the implementation of the United Nation Framework Convention on Climate Change and its Kyoto protocol.Montreal, SCBD, 154p. Technical Series no. 10.
Secretariat of the Convention on Biological Diversity (2009). Connecting Biodiversity and Climate Change Mitigation and Adaptation: Report of the Second Ad Hoc Technical Expert Group on Biodiversity and Climate Change. Montreal, Technical Series No. 41
Vanthomme, Hadrien., Bellé, Boris., Forget, Pierre-Michel (2010). Bushmeat Hunting Alters Recruitment of Large-seeded Plant Species in Central Africa. Biotropica, Volume: 42, Issue: 6, Publisher: Wiley Online Library, Pages: 672-679
Photo: David Thomas