Chemistry Reference
In-Depth Information
d
n
1
r
2
n
g
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1
Figure 2
The temporal balance between soil natural capital (the central thick arrows)
and ecosystem service delivery as a function of soil change. (Source:
adapted from Bristow).
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The actual state describes current stocks, whereas
the inherent state describes that which the soil comes from, and the
attainable state is that which may be obtained through management in
future. A declining state indicates soil resource depletion, whereas an
increasing
state
indicates
soil
resource
accumulation.
If
soil
resources
decline, ecosystem service delivery is also likely to decline.
of as explicit and emergent. The explicit route includes soil goods and services
that we consume directly, e.g. topsoil, peat, etc., whereas the emergent route is
where soils are only one component that contributes to the delivery of final
goods and services from which we derive benefit, e.g. clean water delivery or
flood alleviation.
If this approach is to be used then it is vital that we understand how soils are
changing, both through natural and anthropogenic soil change. Figure 2
shows the link between soil natural capital and ecosystem services and the
concept of soil change, which provides the time element over which change
occurs. Decision making will be concerned with what the current state is and
what the attainable state will be, faced with a number of land-management
options. The impact of decisions can then be monitored; the Countryside
Survey in the United Kingdom
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is one example of this, and is discussed later.
By valuing the changes in stocks, assessment can be made of the impact of
policies and decisions made. Clearly, this approach requires a firm under-
standing of soil change, which forms the focus of the next section.
2 Drivers of Global Soil Change
Pedology, over the last 100 years, has focused extensively on the gradual
change resulting in soil formation, encapsulated in Jenny's five factors of soil
