By definition, ecology refers to the scientific study of interactions between organisms and their environment. However, the trouble with ecology as Robert A. Heinlein puts it is that you never know where to start because everything affects everything else.
The interrelationships of living organisms, plants, animals and their environments is studied with a view to helping discover the principles which govern such relationships a concern for ecology itself. A basic principle based on assumption and an act of faith for ecologists. The interrelationships are brought about by variability among living organisms from all sources including marine, terrestrial, inter alia and other aquatic ecosystems.
For conservationists to enhance the capacity of policymakers in designing good policies to help conserve the biodiverse species, an understanding of the ecosystems services is so critical. Ecosystems services are benefits, people obtain from the ecosystems (MA, 2005) or the conditions and processes through which natural ecosystems and the species that make them up sustain and fulfil human life (Daily, 1997a).
Human communities derive a variety of essential goods and products from the natural environment, including fodder, seafood, game animals, fuel wood and pharmaceutical products; such goods represent an important part of the economy. The natural ecosystems have been less appreciated until recently because of its fundamental life support services that impact greatly human civilisation and without which it would cease to thrive. The roles played by the ecosystem includes; purification of air and water, detoxification and decomposition of wastes, regulation of climate, regeneration of soil fertility, production and maintenance of biodiversity from which several key ingredients of our pharmaceutical, agricultural and industrial enterprises are derived.
These services are generated by a complete complex interplay of natural cycles powered solar energy and operating across a wide range of space and time-scales. The process of waste disposal, for example, involves the life cycle of bacteria as well as other planet-wide cycles of major chemical elements such as carbon and nitrogen. Such process if converted into $ are worth many trillions of dollars annually but because most of these benefits aren’t traded in economic markets, they carry no price tags that could alert society to changes in their supply or deterioration of underlying ecological systems that generate them. Because of the threats increasing to these systems, there’s a critical need for identification and monitoring of ecosystems services both at local and global scale for the incorporation of their value into decision-making processes.
Over time the nature and value of earth’s life support systems have largely been ignored until their disruption or loss highlighted their importance. Deforestation has belatedly revealed the critical role forests serve in regulating the water cycle particularly mitigating floods, droughts, the erosive forces of wind and rain and silting of dams and irrigation canals as examples. Escalating impacts of human today on forests, wetlands, wildlife reserves and other natural ecosystems imperil the delivery of such services.
The primary threats are land use changes that cause losses in biodiversity as well as the disruption of carbon, nitrogen and other biogeochemical cycles; human-induced invasions of species releases toxic substances; possible climate change and depletion of stratospheric ozone. Let’s look in-depth at the values of ecosystem services.
Values for ecosystem services
Ecosystem services can be valued under three categories:
- Ecological value: considers the role of ecosystems in the maintenance of essential life support processes.
- Socio-cultural value: looks at the importance of ecosystems as a measure of non-material wellbeing.
- Economic value: considers the contribution of ecosystems to material prosperity and wealth.
It is important to ensure that the economic (market and non-market) and non-economic values of biodiversity and ecosystem services are taken into account when planning and undertaking ecosystem related activities. This can best be achieved by using a range of valuation techniques. Some of these methods include:
- Total Economic Value (TEV): This provides monetary values to ecosystem services (can be direct or indirect).
- Choice Model
- Cost: Benefit Analysis (CBA)
- Total Economic Value (TEV)
Here we have the following:
- Direct use values
– Onsite fishery
– Non-Timber Forest Products (NTFP)
– Onsite agroforestry
– Onsite tourism
- Indirect use values
– Offsite fishery
– Water supply
– Pest control
– Fire prevention
– Flood control
– Carbon sequestration
– Bequest, option and existence values
– Biodiversity conservation programme
– (Inter)national donations
- Choice Model
This model is used to assess the willingness of the communities to abandon the current activities and opt for alternative livelihoods. It is presented in the form of repeated choices.
More specifically, respondents are asked to choose between alternative circumstances
– The circumstances are defined in the form of land conversion to a forest, access to the forest, subsidies for buying farm inputs, extension services and provision of land titles.
- Cost: Benefit Analysis (CBA)
This model looks into stream of investment and production costs of existing livelihoods such as agricultural undertaking with the flow of benefits it produces
It assess the opportunity cost for the people to select ecosystem services considerably
– Identifying the main Ecosystem Services in the landscape
– Quantifying a number of each Ecosystem Services produced by ecosystem in the last period
– Estimating the value of each input that was used in the production process of major Ecosystem services in the last season
What are Costs Considered?
- Total costs of land-use change incurred by ecosystem service (ES) providers under different scenarios.
- Such costs consisted of the costs of
1 implementation (one-off costs incurred in the first year) and
2 opportunity costs for land taken out of productive use (recurring over the life of the project).
What are Benefits Considered?
- Payments / compensation made under the Payment for Ecosystem Services (PES) Programme equivalent to the compensation variation (or costs to ES providers) for implementing conservation measures as required under the PES Programme.
- Improved on-farm productivity.
- Reduced soil erosion.
Ecosystem service trade-offs
- Temporal trade-offs: benefits now – costs later
- Spatial trade-offs: benefits here – costs there
- Beneficiary trade-offs: some win – others lose
- Service trade-offs: manage for one service – lose another
1. ODUM, E.P. (1971). Fundamental of Ecology. 3rd ed. W.B. Sunders Co. pp. 574
2. COLINVAUX, P. (1986). Ecology, 1st ed, John Wiley & Sons Inc. pp. 725. ISBN 0-471-1652-6.
3. RICKLEFS, R. E. (1990). Ecology, W.H. Freeman and Co., pp. 896 ISBN 0-7167-2077-9
4. KREBS, C.J. (1994). Ecology: The Experimental Analysis of Distribution and Abundance, 4th Ed. Addison Wesley Educational Publishers, Inc. pp 801. ISBN 0-06-500410-8
5. MILLER, G.T. (1998). Living in the Environment; Principles, Connections and Solutions, 10th Ed, Wadsworth Publ. Co., N/Y, pp 759, ISBN 0-534-51912-1