Chapter 7 . Stream Ecosystem Analysis
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Figure 7.3. Similarities of the 55 sampIes with regard to eight water properties
visualised by a Sammon map of a 15x12 SOM.
7.4
Correlations and Predictions with Supervised Learning
Systems
Ecological systems (ecosystems) consist of the biological community and the
abiotic environment. Many simultaneous and complex interrelations exist among
the environmental variables, between the environment and the community, and
within the members of the community. Many dependencies can be described by
multiple non-linear regressions, a typical task for supervised learning ANNs.
However, these are not necessarily cause-effect relations. The multitude of
relationships typically implies redundant information. Important predictors either
have to be selected or information must be compressed.
This is the required information to model relationships within the environment
or the community, and to predict at least parts of the biological community from
information on the environment and vice versa (bio-indication).