The ecosystem perspective provides a framework within which most other
aspects of the ecology of restoration can be incorporated. By conside
ring the ecosystem functions of a restoration project, the restoration
ist is forced to consider the placement of the project in the landscap
e-its boundaries, its connections or lack thereof to adjoining ecosyst
ems, and its receipts and losses of materials and energy from its phys
ical surroundings. These characteristics may set limits on the kind(s)
of biotic communities that can be created on the site. The ecosystem
perspective also gives restorationists conceptual tools for structurin
g and evaluating restorations. These include the mass balance approach
to nutrient, pollutant, and energy budgets; subsidy/stress effects of
inputs; food web architecture; feedback among ecosystem components; e
fficiency of nutrient transfers, primary productivity and decompositio
n as system-determining rates; and disturbance regimes. However, there
are many uncertainties concerning these concepts, their relation to e
ach other, and their relationships to population-and community-level p
henomena. The nature of restoration projects provides a unique opportu
nity for research on these problems; the large spatial scale of restor
ations and the freedom to manipulate species, soil, water, and even th
e landscape could allow ecosystem-level experiments to be conducted th
at could not be performed otherwise.