We rely on the natural world for a seemingly limitless supply of free natural resources, everything from the air we breathe to the pleasure we get from walking through a forest or gazing at the surrounding landscape from a mountain top. This was once referred to quaintly as ‘nature’s bounty’. However, to emphasise the critical role of nature in human commerce and society, the language of sustainability science now uses the much less colourful and more market-orientated expression ‘ecosystem services’[4] to mean essentially the same thing.[1] This economic metaphor compares natural resources (as ‘natural capital’[5]) to capital assets needed for the flow of services and which cannot be depleted without serious consequences. The metaphor is sometimes pushed further to discuss items like ‘natural infrastructure’ as resource-supplying structures like rivers, forests, wetlands and so on. The concept also highlights the fact that we treat many natural assets as if they had no value. Clearing forests, developing coastlines, adding CO2 to the atmosphere and many other environmental impacts generally benefit only a small sector of society while overall natural capital is eroded.
As natural resources become depleted we are becoming increasingly aware of our need to protect what is left, so in recent years we have seen the increasing use of market mechanisms (carbon and water credits, taxes, financial incentives etc.) to tackle the problem of nature being treated as an economic externality.[3]
The following diagram produced in in the Millennium Ecosystem Assessment (2005) captures important links between the environment, society, economics, and our sense of well-being. It is the attempt to integrate all those factors that are collectively at the heart of what we mean by sustainability: it is about ‘… the overlooked resources upon which human welfare, wealth creation, and quality of life depend‘.

Ecosystem Services
Chart indicating the major environmental factors that influence human wellbeing
Courtesy Millennium Ecosystem Asessment 2005
NATURAL RESOURCES
This article examines the many ways in which humans depend on nature, the community of life. These are biogeochemical resources that are necessary for life to exist at all, not just those that enhance our lives. Expressed in the simplest terms our integration with the world begins with our depenedence on interactions with inorganic energy, water, and materials – although as living organisms we interact in many ways with our fellow organisms, the community of life (biodiversity or the biosphere) which is our source of food. Although all these factors are closely integrated, their significance is addressed in independent articles on elements of both geodiversity[7] (energy, water, materials) food as a requirement for life, and biodiversity.[6]
History & resources
We do not read much about about resources in history books because their presence in our lives, like the air we breathe, is generally taken for granted, they are a given. Besides, we are accustomed to history emphasizing political and cultural matters. Now, in the 21st century, it is clear that natural resources can no longer be taken for granted. As the Anthropocene unfolds we are becoming increasingly aware of our influence on the planet and our interaction with the community of life. Expanding populations and urbanization have led to longer transport routes, more remote supply chains, and globalization. Global short-supply increases awareness of the role played by ecosystem services in human lives of the past since only now do we realize their potential to affect our future sustainability. If human history is the attempt to track those factors exerting the greatest influence on the course of individual and collective human lives then our awarenss of the potential impacts of diminishing resources now prompts us to look back to the factors that created this circumstance. We now look back, with the benefit of hindsight, at the significance of the environment in not only traditions and belief, but as the manipulation of flows of energy, water, materials, and organisms that have created civilizations and artificial (human or man-made) landscapes across the world. This is yet another reinterpretation of history made necesssary by present circumstances and performed as preparation for the future.
Categorizing ecosystem services
In any complex interactive system the choice of categories to describe and explain that system can be a difficult matter. The choice of provisioning, regulating, cultural, and supporting services reflects qualitative differences – other classifications might have different criteria. This classification draws attention to non-material (psychological or spiritual) benefits as wellbeing in addition to direct physical goods and services. There is a cascade of ideas from ecosystem, to function, to service, to benefit, to value that is the foundation for an environmental ethic. Markets at present do not do enough to recognize these values and the contribution made to the trade in goods and services.
Scarcity & substitution
In economics the loss of a resource can be addressed by replacing it with another as ‘substitution’. Ploughed grassland might provide arable land for the service of food production. But since ecological interactions are complex we cannot be sure of either the long term effects and the impact on other ecosystem services. technology can certainly provide some substitution capacity. What we do know for sure is that ecosystems are not limitless so our economics must take this into account: only a clear understanding of the operations of ecosytems and their natural limits must underpin any program of substitution.
COMMENTARY
The model of ecosystem services presented here presents an antropocentric framework of ideas … it is about nature as human utility that provides wellbeing. Nevertheless, human wellbeing mostly coincides with the wellbeing of the rest of the community of life. The idea itself provides a mechanism for introducing a consideration of nature into public policy providing the language and tools needed to guide us towards a sustainable future.
Citations & notes
[1] The definition given in the UNEP Millennium Ecosystem Assessment (2005) Ecosystem Services are … the benefits people obtain from ecosystems
[2] Everard 2017, p. 1
[3] An economic externality is a cost or benefit that affects a party that did not choose to incur that cost or benefit. The benefit I get from fresh air or the inconvenience I suffer from smog. Where ‘externalities’ are unappreciated (and therefore often abused) policies can be developed to ‘internalize’ the externality
[4] The expression ‘ecosystem services’ was first coined in the 1960s and fleshed out by Paul and Ann Ehrlich is books like population, Resources, Environment: Issues in Human Ecology (1970)
[5] The expression ‘natural capital’ refers to th eworld’s stocks of natural assets which include geology, soil, air, water, and the community of life
[6] Biodiversity (biological diversity) is a summary term encompassing the full variability of living organisms and their environments
[7] Geodiversity is the variety of rocks, fossils, minerals, natural processes, landforms and soils that create the character of our landscape and environment
General reference
Everard, M. 2017. Ecosystem Services. Earthscan: New York
UNEP Millennium Ecosystem Assessment http://www.unep.org/maweb/en/index.aspx 2005