CONCLUSION
This case demonstrates three key inter-related principles. First, that large-scale
action that manipulates freshwater ecosystems should not be undertaken
without consideration of the ecological impacts of those actions. Every choice
has consequences. Some are beneficial, serving to help restore degraded systems.
Some are detrimental to the ecological health of the system, but may need to
proceed for other reasons. Most choices have elements of both, causing some
ecological disruption over some time horizon, but having some positive
ecological consequences as well. To govern ourselves effectively, we must be
aware of the full range of consequences our choices generate.
Second, ecological consequences are often distant in both space and time
from the action(s) that cause them. This case shows how loggers at the end of
one century can impact swimmers in the middle of the next. Yet, this lesson cuts
two ways. First, it teaches us to be careful about actions that have negative
impacts that may not appear immediately, but occur downstream affecting our
neighbors or in the future affecting our children. It also reminds us that distant
populations matter. The Great Lakes will suffer cumulative adverse impact
from the actions of distant peoples. Second, and this is the under-appreciated
good news, cumulative positive consequences will also lag the actions that
produce them. Seemingly isolated good works, such as restoring wetlands or
returning natural flow regimes to tributaries, will generate increasingly positive
returns once there is a “critical mass” of such activity. Consciously choosing
restorative alternatives – those that create ecological wealth, over sufficiently
long time and space scales – will produce synergies that truly make the whole
greater than the sum of the parts. This is the nature of systems. Both the distant
positive and negative effects need to be considered in governance decisions.
Third, it is necessary to think expansively about the relationship of human
populations to freshwater ecosystems. It is tempting, for example, to think of
only those humans who live near a lake or river system as the human population
that matters. However, ecological systems do not necessarily work that way.
While a complete analysis is unlikely to not consider such local populations,
those who live far away geographically, or have yet to be born, may be the
stakeholders that matter most, and will drive governance action. It depends on
what those human populations are doing. Freshwater ecosystems have many
different human populations that affect them, and that are effected by them.
Usually, simple measures like amount of water consumed, land developed, or
pollution produced, are not, by themselves, useful measures of ecological
harm. Neither are acres of open space, area of buffer strips, or number of rare
species, useful measures of ecological health. The key is to understand the
relationship that a series, or set, of human populations has with the ecological
system, and which key ecological processes are being compromised or restored
to health in that relationship. Such processes can be thought of as master
variables and include natural flow regimes, the full complement of native
species and functional niches, and a natural chemical regime. We must minimize
disruptions to intact, healthy processes, and restore those that have been
adversely impacted.