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pioneer, building, mature, and degenerate phases (Watt 1947). Such communities could persist
over time because at large spatial scales, a heterogeneous landscape would contain numerous
patches at each phase. Only a major disturbance at much larger spatial scales like clear felling,
wildfire, or hurricane would disrupt this stability. Watt was perhaps the earliest ecologist to
make explicit the critical link between pattern, process, and scale that went on to be the foun-
dation for landscape ecology (Allen and Starr 1982, O'Neill et al. 1986, Levin 1992, Christensen
et al. 1996) and provided direction for one of the biggest shifts in ecological thinking since the
birth of the discipline; the move from equilibrium to non-equilibrium thinking (Wu and
Loucks 1995, Pickett et al. 1997). Some of the major themes to emerge over this incredibly fertile
period in ecological history were that resources, populations and carrying capacity all change
over time in response to ongoing climate change, natural disturbance and human manage-
ment. In dynamic systems, consideration of scale is critical to understanding and managing
spatial heterogeneity and temporal variability (Wu and Loucks 1995, Wedell 2002, Gillson and
Willis 2004).
Ecosystem management: coping with complexity
As ecologists realized the dynamic and complex nature of ecosystems, the search began for
new conservation approaches for ecosystems that were heterogeneous, variable, non-linear,
and full of surprises (Grumbine 1994, Holling 1996b). The landscapes that early conservation-
ists perceived as stable were in fact dynamic systems in flux, and a new type of conservation
was needed to cope with this complexity (Funtowicz and Ravetz 1994, Grumbine 1994, Chris-
tensen et  al. 1996, Ravetz and Funtowicz 1999). Critically, a temporal understanding was
needed to provide context for the landscapes and changes observed today and to understand
variability and response in ecosystems. It is not possible to understand the fundamental link-
age between pattern, process, and scale without understanding change over timescales that
are ecologically realistic.
Conserving landscapes that are in flux is in many ways paradoxical to ecologists, manag-
ers, and conservation practitioners accustomed to perceiving their role as keepers and
students of nature's balance. They are now faced with the challenge of how to conserve eco-
systems that moving targets in a dynamic and uncertain world. New conceptual frameworks
and conservation approaches are developing that help scientists and managers to make
urgent decisions in the face of climate disruption, extinctions, loss of diverse ecosystems, pol-
lution, and consumption patterns (Barnosky et  al. 2014). Ecosystem management (also
known as the ecosystem approach) recognizes the dynamic, complex, and uncertain nature
of ecosystems, as well as the limits of their resilience and the role of human values in their
conservation and management (Grumbine 1994, 1997, Christensen et al. 1996, Holling 1996b,
Yaffee 1996, Smith and Maltby 2003, Folke et al. 2004). Furthermore, in ecosystem manage-
ment, the relationship between people and nature is being re-established, and new ways of
conceptualizing humans as part of linked socioecological systems are developing (Holling
1996b, Gunderson and Holling 2001, Berkes et al. 2003). In 2000, the Ecosystem Approach was
 
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