Can the future of an ecosytem really be that hard to predict?
An ecosystem is similar to the picture by Bruegel in 1556, although it appears black and white, there is a high amount of complexity and activity that takes more than one look to understand. Guy Woodward, Imperial college London, in a recent seminar explains the threats and predicts the future for upland aquatic ecosystems.
Guy works closely with the DURESS project (Diversity of Upland Rivers for Ecosystem Service Stability) who have made several key discoveries about the changes to upland rivers that surround heavy industrialised and agricultural areas.
A majority of their work has discovered that industrial runoff gathers in upland rivers, increasing the acidification of the ecosystem.
This has had drastic effects on major predators, for example, trout (O. mykiss), by causing the degradation of their gills, which are sensitive to the pH balance and heavy metal content of the water. The image above demonstrates the damage, metals and ammonia, from industrial runoff, can have.
This, according to Guy, can have a massive and yet unquantified knock on effect on the upland river ecosystem.
He predicts four possible outcomes for the future of these ecosystems;
Further agriculture for a growing populous will increase fertiliser run off into the upland systems creating a rapid increase in plant biota downstream. This may force organisms to migrate upstream away from the damaged area of bioaccumulation.
Hopefully, the observed drastic effects on upland aquatic ecosystems will lead to further management of the area. This is likely to take the form of continued water quality assessments and maintenance of pH via collecting runoff samples. This could also lead to further legislation.
An always possible outcome is that the slow acidification of rivers from industry and agriculture has little to no major impacts of the ecosystem complexity. Although, this seems unlikely because most human intervention on ecosystems has caused a change of some sort.
However, there may be unexpected compensation effects or complexity to the upland aquatic system that can provide as an insurance to the system if polluted.
If no management options are taken up and there is an increase in acidification effects on the ecosystem, upland ecosystems that are affected by industry could be irreversibly damaged. So much so that it could cause a complete ecosystem cascade impacting surrounding ecosystems.
Overall, this talk has not only think made me think deeper into the impacts humans have on smaller upland ecosystems but also on the downstream and larger ecosystem effects on the ocean environment too.
Trophic Level Complexity
A major part of this talk for me was the scope it gave to me when I now think about trophic levels within an environment. It has made me think that the environment is more like a giant 4D Rubix cube.
Where complexity and unknown factors of survival can hinge upon the smallest change in the environment. Leading to a few direct and hundreds of indirect ecosystem impacts.
Thus, these impacts could cause the complexity to change, mixing variables and species that could trigger responses that return the ‘Rubix cube’ back to its original system. Or further cascade new moves into a completely new system and predator-prey organisation.
Which further adds to my amazement, of the insightfulness, of Pieter Bruegel who died over 400 years ago, but still showed that the natural environment is extremely complex. And is furtherly complex when human start to mess with and dissect it.