in Bangor University Seminars


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.

Nor­mal gill arch­es (left), Gill arch­es from a trout in an indus­tri­al run off riv­er (right)

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.

Ecosystem Managment

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.

No Change

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.