Geoscience Reference
In-Depth Information
only been recorded within the last century (see, e.g., Pullin and Knight, 2001). For
example, the aim of heathland conservation in the UK is to maintain heathland by
preventing the encroachment of scrub. This approach mistakenly associates the
halting of successional dynamics with the preservation of a 'rare' or 'endangered'
habitat, and is both unnatural and doomed to failure. The same is true of species
conservation targeting single species in isolation. Such strategies are unlikely to
succeed if associated ecosystem structure, functioning and variability are not con-
served or restored at the same time. The artifi cial preservation of habitats and species
at a given, anthropogenically conceived state should not be the main target of
conservation and restoration. Instead the return of ecosystem dynamism, function-
ing and integrity should be paramount (e.g., Murphy, 1989; van Kooten, 1998).
Future Challenges
Key future challenges in quantifying ecosystem resource variability and improving
prediction include:
integrating the principles of ecosystem variability, dynamism, and non-
equilibrium states into ecosystem resource and service management, including
an economic acceptance of the value of such variability;
allowing for some level of natural variability in ecosystem management, includ-
ing the acceptance of associated risks;
relaxing management where appropriate to allow for the restoration of ecosys-
tem variability and dynamism;
developing and validating non-linear ecosystem and resource models to increase
predictive potential;
utilising new geographical technologies and landscape ecological metrics to
obtain and analyse data regarding variability of ecosystem structure and process
over a range of spatial and temporal scales (particularly broad scales), to inform
modelling and management; and
obtaining comprehensive measurements of biotic and abiotic interactions across
whole ecosystems to increase confi dence in our understanding, despite the cost
and effort involved.
Conclusions
Our early understanding of ecosystems as simple, mechanistic, and predictable
systems, conceptualised at the start of the 20th century, has recently developed to
a more detailed understanding of the complex, chaotic, non-linear, and above all
unpredictable
nature of ecosystems and their resources. In particular, the variability
of patterns and processes within ecosystems is problematic to quantify due to their
complexity and our insuffi cient understanding of the many interactions between
ecosystem components, their strengths, and their signifi cance.
This lack of understanding creates problems for ecosystem and resource manage-
ment, which requires predictability. Management is further complicated by uncer-
tainty over which spatio-temporal scale is most relevant to both the specifi c resource
and the wider ecosystem. With increasing evidence to support the importance of
ecosystem dynamism and variability, these characteristics can now be regarded as
resources with intrinsic value and which do ideally not need managing or restricting,
