Environmental Engineering Reference
In-Depth Information
include more entities (components) and processes (fluxes among the components) encom-
passing both biotic and abiotic interactions that influence nitrate. Such a model would
probably be based on a mass balance. The inclusiveness aspect of ecosystem science pro-
motes the deeper exploration of complex interactions that influence important system attri-
butes like river nitrate.
The flexibility of the ecosystem concept allows one to boil down many interactions into
a simple form that can be particularly useful for prediction and comparison. Similarly,
flexibility allows us to focus on interactions and multiple contributing processes.
Returning to the two philosophical perspectives, a deductive approach that developed a
detailed nitrogen model for the river nitrate problem would provide hypotheses in the
form of testable predictions. These predictions could be analyzed by experiments and/or
measurement programs. A synthetic approach might pose a number of models of varying
complexity and seek to develop a spectrum of model predictions that could be compared
with existing data, new measurements, or experimental results.
There is no single path to generality. Students of ecology are advised to consider many
models and varying approaches that together provide the means to investigate ecosystems
(
Carpenter 1998
). The ecosystem concept provides a powerful framework for investigating
many (but not all) ecological problems. The discipline of boundary setting and mass bal-
ance combined with inclusiveness and flexibility are key components of the concept that
promote effective implementation of ecosystem studies.
References
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