Ecosystem goods and services provide humans with many necessities of life and survival. Ecosystems perform numerous functions. Many of those functions are valued by humans because they deliver us ecosystem services. ES include such processes as biological control of pests, weeds and diseases, pollination of crops, amelioration of flooding and wind erosion, provision of food (including fisheries), hydropower for electricity generation, capture of carbon dioxide by plants and carbon by soil, landscapes that are enjoyed by residents and tourists among others.
A pivotal paper in Nature by Robert Costanza et al. (1997) used a range of methods to estimate the economic value of ES worldwide. Their central estimate was US$33 trillion (1012) per annum. Costanza’s valuation stimulated much debate, including the suggestion that US$33 trillion is “a serious underestimate of infinity”. In other words, mankind cannot survive without ES, so estimating their total value is futile. Also in 1997, Gretchen Daily, of Stanford University published an important book entitled “Nature’s Services” which studied, in some detail the roles of ES Those two publications led to a change in the paradigm within which mankind’s dependence on living things is viewed. However, Costanza et al., and Daily concentrated largely on “natural” ecosystems and biomes, such as boreal forests, coral reefs, mangroves and attributed low dollar value to highly modified or “engineered” ecosystems such as farmland, forestry and cities.
More than 50% of the world’s population lives in cities and this proportion is increasing by 1-2% per annum. The “ecological footprint” of cities is enormous and, with cities such as Shanghai being predicted to grow from 17 million to 70 million over the next decade, the extent to which cities can support themselves in even a limited number of functions is likely to continue to decline. London for instance consumes the food equivalent to the total food production of the UK with enormous associated external effects on human health and the environment.
A recent FAO publication “The state of food and agriculture” (2007) notes the importance of agriculture in the provision of ES. The FAO note that “… farmers are the largest group of natural resource managers on Earth”. Some of the ES provided from agriculture (e.g. food, wood and fibre) are priced in markets and their value well understood. Others, perhaps most, are currently unpriced and unnoticed in many instances and hence their value is poorly understood. Estimating the value of ‘marginal changes’ in ES associated with proposed projects, plan or policy changes may be much more useful than attempting to estimate total value.
In terms of the future of agriculture, the following quotation from David Tillman, a pioneer in the area of the science of sustainable agriculture, is very timely:
“New incentives and policies for ensuring the sustainability of agriculture and ecosystem services will be crucial if human populations are to meet the demands of improving yields without compromising environmental integrity or public health”. Tilman et al. (20002).
A focus on ES is useful because it can alert us to the need to do more than increase production and profit in commercial activities. Avoiding damage to one ES may be as socially valuable as increasing another. ES provide a framework that may provide us insights that are hidden by fragmentation into cultural, social, environmental and economic values.
Several researchers at Lincoln University, New Zealand are measuring, quantifying, valuing and enhancing ES. A major research project funded by Foundation for Research Science and Technology, LINX0303, developed ways to enhance or maintain ES in agriculture. It also estimated values for marginal changes in the level of some ecosystem services linked to agriculture and viticulture. Researchers in that FRST funded project collaborated with colleagues at University of Vermont in the USA. One outcome of the collaboration was the development of this publicly accessible website to report research results, provide information about ES, and illustrate values of selected ES in Canterbury, New Zealand. The research includes field level measurement of ES Sandhu et al., (2007), international collaboration on ES research Porter et al., (2009), estimation of ES values at regional level Baskaran et al., (2009). Research outputs from the LINX0303 project are listed on webpages of staff accessible from the Greening Waipara Research site.
Our own Ecosystem Services research theme site is a vehicle to report ongoing work by Lincoln University staff and collaborators on ES. One area for ongoing research is the Greening Waipara project.
References
Baskaran, R., Cullen, R. , Takatsuka, Y. (2009). Estimating the Value of Agricultural Ecosystem Service: A case study of New Zealand Pastoral Farming. Australasian Journal of Environmental Management. 16(2), 103-112.
Costanza, R., d’Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburge, K., Neem, S., O’Neil, R., Parelo, J., Raskin, R., Sutton, P., van den Belt, V. (1997). The Value
of the World’s Ecosystem Services and Natural Capital. Nature, 387, 253-259.
FAO, 2007. The state of food and agriculture. FAO, Rome. Gretchen, D. (ed.) (1997). Nature’s Services: Society Dependence on Natural Ecosystem.
Washington DC, Island Press.
Sandhu, H., Wratten, S. and Cullen R. (2007) Field evaluation of ecosystem services in arable land. Agriculture, Ecosystems and the Environment 5: 39- 50.
Tilman, D., Cassman, G., Matson, P.A., Naylor, R., and Polasky, S. (2002). Agricultural sustainability and intensive production practices. Nature, 418, 671-677.
Porter, J., Costanza, R., Sandhu, H., Sigsgaard, L., and Wratten, S. (2009). The Value of Producing Food, Energy, and Ecosystem Services within an Agro-Ecosystem. Ambio, 38(4), 186-193.