World’s Soil Resources

7 | The impact of soil change
on ecosystem services
7.1 | Introduction
Soils are now recognized to be in the ‘front line’ of global environmental change and we need to be able to
predict how they will respond to changing climate, vegetation, erosion and pollution. This requires a better
understanding of the role of soils in the Earth system to ensure that they continue to provide for humanity
and the natural world (Schmidt et al., 2011). Although only a thin layer of material at the Earth’s surface, soils
like many interfaces play a pivotal role in regulating the flow and transfer of mass and energy between the
atmosphere, biosphere, hydrosphere and lithosphere. Moreover, the structure and organization of soils leaves
an important imprint on the Earth’s surface in terms of how land is used and how ecosystems develop. Soils
help regulate the Earth’s physical processes such as water and energy balances, and act as the biogeochemical
engine at the heart of many of the Earth system cycles and processes on which life depends. Some soil processes
contribute directly to the delivery of ecosystem goods and services, while other soil processes influence the
delivery of goods and services. This section examines how soil processes affect soil and ecosystem function
and the production of goods and services of benefit to humanity.
Humanity has had an indelible impact on the Earth’s surface, so much so that it has been proposed that the
planet has entered a new geological epoch, the Anthropocene (Crutzen, 2002). A population of ca. 7 billion
people that will likely grow to 9.6 billion by 2050 is stressing Earth’s resources. Maintaining the planet in an
equitable state for human life is perhaps our greatest challenge. Currently, humans have adapted 38 percent
of the earth’s ice-free land surface to agriculture, crops and pasture (Foley et al., 2011). Agricultural production,
driven by the need to produce food for a growing population, has had a tremendous impact on our ecosystems
and resources, especially through the abstraction of water and the leaving of residues. Rockström et al. (2009)
proposed that we need a ‘safe operating space for humanity with respect to the Earth system’. They argue that
that there exist biophysical planetary boundaries (or thresholds) which it is inadvisable to cross if we are to
maintain the needed balance. Vince and Raworth (2012) adapted these concepts to include social goals (1).
This presentation underlines the fact that we live in a coupled human earth system. The ecosystem services
analytic approach has been developed in order to bridge the science/policy divide. The approach aims to make
the concepts clear for all and to set out what needs to be considered in order for humanity to live within
sustainable boundaries.
Status of the World’s Soil Resources | Main Report The impact of soil change on ecosystem services
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