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S.P. Thrush and R.B. Whitlach
scale large and slow processes control smaller scale events but also nature can
surprise us and the latter can affect the former (Holling 1996). However,
despite the scale dependence of their results, field experiments are still
powerful tools in developing a mechanistic understanding and revealing the
importance of life and natural history characteristics of component species.
For example, general predictions of the consequences of habitat disturbance
by commercial fishing, based on the results of field experiments and natural
history characteristics (e.g., changes in biodiversity, density of epifauna and
large and long -lived species), have been tested and largely validated by broadscale surveys (Thrush et al. 1998). The power of inference drawn from such
broad-scale surveys is greatly increased by the ability to make a priori
predictions. Thus, while direct scaling-up may be difficult, useful information
can be generated and used in an iterative process of prediction and testing to
assess broad-scale effects. Elsewhere we have discussed various strategies that
are available to improve our ability to scale-up experimental results (Thrush
et al. 1997b, 1999,2000).
The opportunity of working in different locations is always exciting and
most field ecologists are quick to identify both the differences and similarities
in ecological patterns and process. Thus comparative ecology is an intuitively
useful way of discerning generality. But how do we move from intuition to
quantification and theory? In this chapter we have intentionally focused on
disturbance-recovery experiments that have been conducted with our colleagues in New Zealand or New England (USA). We also attempt to develop a
conceptual framework to generalise across localities to measure the dynamic
response of benthic communities to disturbance and thus assess their resilience. In order to generalise using experimental results some knowledge of
how recovery processes vary with location or with the size of the area
disturbed is vital. Both issues need to be addressed if we are to make benthic
ecology more predictive. These issues are particularly important when
addressing human impacts on marine benthos because we are often
concerned with extensive, broad-scale and chronic changes. Usually we do not
have pre-disturbance data, adequate knowledge of site history or availability
of adequate control sites. Potentially, broad-scale degradation of benthic
ecosystem health requires the development of appropriate empirical tools to
identify broad -scale changes in recovery. If we can develop a way to generalise
across localities it may be possible to measure the dynamic response of
benthic communities to disturbance and thus assess their resilience to natural
and anthropogenic disturbance.
S.P. Thrush and R.B. Whitlach
scale large and slow processes control smaller scale events but also nature can
surprise us and the latter can affect the former (Holling 1996). However,
despite the scale dependence of their results, field experiments are still
powerful tools in developing a mechanistic understanding and revealing the
importance of life and natural history characteristics of component species.
For example, general predictions of the consequences of habitat disturbance
by commercial fishing, based on the results of field experiments and natural
history characteristics (e.g., changes in biodiversity, density of epifauna and
large and long -lived species), have been tested and largely validated by broadscale surveys (Thrush et al. 1998). The power of inference drawn from such
broad-scale surveys is greatly increased by the ability to make a priori
predictions. Thus, while direct scaling-up may be difficult, useful information
can be generated and used in an iterative process of prediction and testing to
assess broad-scale effects. Elsewhere we have discussed various strategies that
are available to improve our ability to scale-up experimental results (Thrush
et al. 1997b, 1999,2000).
The opportunity of working in different locations is always exciting and
most field ecologists are quick to identify both the differences and similarities
in ecological patterns and process. Thus comparative ecology is an intuitively
useful way of discerning generality. But how do we move from intuition to
quantification and theory? In this chapter we have intentionally focused on
disturbance-recovery experiments that have been conducted with our colleagues in New Zealand or New England (USA). We also attempt to develop a
conceptual framework to generalise across localities to measure the dynamic
response of benthic communities to disturbance and thus assess their resilience. In order to generalise using experimental results some knowledge of
how recovery processes vary with location or with the size of the area
disturbed is vital. Both issues need to be addressed if we are to make benthic
ecology more predictive. These issues are particularly important when
addressing human impacts on marine benthos because we are often
concerned with extensive, broad-scale and chronic changes. Usually we do not
have pre-disturbance data, adequate knowledge of site history or availability
of adequate control sites. Potentially, broad-scale degradation of benthic
ecosystem health requires the development of appropriate empirical tools to
identify broad -scale changes in recovery. If we can develop a way to generalise
across localities it may be possible to measure the dynamic response of
benthic communities to disturbance and thus assess their resilience to natural
and anthropogenic disturbance.