By Luisana Carballo
As a biologist interested in conservation I appreciate life for its intrinsic value and I am concerned about how humans are threatening the prevalence of other species on Earth to ensure their own. However, I realise the existing conflict between humans and wildlife as the latter can threaten the wellbeing of humans. Carnivores such as cheetahs and lions usually feed on livestock, directly affecting farmers that make a living primarily or solely from their cattle. Elephants can devastate not only entire crops but also the homes of people that live close to their territory. With these kinds of situations I understand that some people may wonder if preserving biodiversity is going to bring any benefit or if it is going to be detrimental.
Nowadays news about biodiversity conservation is all over the world. This is partly due to the continuous increase in the number of species within the threatened category of the IUCN(1) (19,265 species out of the 59,507 assessed at present are threatened with extinction). The main threats to biodiversity listed by the IUCN are: habitat loss and degradation, introduction of invasive alien species, over-exploitation of natural resources, pollution and diseases, and human-induced climate change(1). All these are caused by humans, fuelled by our exponential growth.
Is there any common ground for biodiversity conservation and human progress?
Ecosystem services is a term that refers to the benefits that humans can obtain from ecosystems through goods such as food, fuel, timber or tourism. Biodiversity plays a fundamental role in the production of ecosystem services, as these are the results of the interactions between biotic and abiotic components that involve ecological and evolutionary processes.
Important evidence of the last 20 years of research in the field of biodiversity and ecosystem functioning (BEF)(4) shows how biodiversity has an impact on the functioning of ecosystems:
- Biodiversity loss reduces the efficiency by which communities capture biologically essential resources (light, water, nutrients) and convert them into biomass.
- Biodiversity increases the stability of ecosystem functions. More diverse communities capture resources in a more stable manner, thereby strengthening biomass production.
- Biodiversity loss accelerates the rate of changes in ecosystem processes.
- More diverse communities are more productive, as the functional traits of different organisms increase the capture of resources.
- Loss of biodiversity across trophic levels has a great impact in the function of the ecosystem. The loss of higher consumers can ultimately reduce plant biomass and can also alter vegetation structure, fire frequency, and even disease epidemic.
- Certain traits of organisms can have crucial effects on particular ecosystem processes. If a key trait is eliminated so would be the underlying process.
Management actions that regulate the dynamics of ecosystem services can also be beneficial for biodiversity conservation, a win-win scenario(3). For example, actions to conserve rivers to obtain clear water provision will also protect river-dependent species. Although not all scenarios are win-win, a common ground indeed exists and we could benefit from increasing efforts to preserve both, biodiversity and ecosystem services.
Bateman et al.(5) built a model of land-use in the UK taking into account marketed and non-marketed goods. The results showed that under a scenario in which strong environmental policies are applied to reduce land-use by agriculture, there are gains in the value of ecosystem services thanks to reductions in greenhouse gasses emissions, increase in recreation and urban green space, as well as improvements in species diversity. Non-marketed goods are highly appreciated by UK people as this is a country where food is accessible but chances to enjoy nature and recreation are limited(5). This scenario may vary in countries where food is less accessible hence has a higher value for people.
Biodiversity conservation and the exploitation of ecosystem services are not mutually exclusive. Reyers et al.(3) argued that “the common ground that exists between biodiversity and ecosystem services has the potential to play a powerful role in evolving our ability to address the sustainability challenges that we face”.
Conservation of biodiversity can be embraced within the ecosystem services context, and this must be seen as a new strategy for biodiversity conservation(2). There is no reason to think that this strategy could threaten the traditional way to conserve for the, in fact the ecosystem services approach provides a broader perspective for the conservation field(2).
A common ground exists, and we need to embrace every possible strategy that will allow us to preserve the existing diversity in Earth, especially those who, like me, appreciate life for its intrinsic value and will work toward the conservation of species.
1. IUCN – Home [Internet]. Available from: http://www.iucn.org/
2. Mace GM, Norris K, Fitter AH. Biodiversity and ecosystem services: a multilayered relationship. Trends Ecol. Evol. [Internet]. Elsevier Ltd; 2012 Jan [cited 2013 Nov 7];27(1):19–26. Available from: http://www.ncbi.nlm.nih.gov/pubmed/21943703
3. Reyers B, Polasky S, Tallis H. Finding common ground for biodiversity and ecosystem services. Bioscience [Internet]. 2012 [cited 2013 Dec 1];62(5):503–7. Available from: http://www.bioone.org/doi/pdf/10.1525/bio.2012.62.5.12
4. Cardinale BJ, Duffy JE, Gonzalez A, Hooper DU, Perrings C, Venail P, et al. Biodiversity loss and its impact on humanity. Nature [Internet]. 2012 Jun 7 [cited 2013 Nov 6];486(7401):59–67. Available from: http://www.ncbi.nlm.nih.gov/pubmed/22678280
5. Bateman IJ, Harwood AR, Mace GM, Watson RT, Abson DJ, Andrews B, et al. Bringing ecosystem services into economic decision-making: land use in the United Kingdom. Science [Internet]. 2013 Jul 5 [cited 2013 Nov 8];341(6141):45–50. Available from: http://www.ncbi.nlm.nih.gov/pubmed/23828934