I am a fan of the conceptual parti of the ‘ecotone’ as seen from the Integrating Habitats competition award winner ‘Urban Ecotones’ from 2008. The use of this landscape ecology principle, which is defined as a transitional zone between distinct plant communities, offers a lot of mileage as an evocative strategy within it’s original sphere of influence, as well as being re-purposed as a metaphor in urbanism and more developed strategies.
:: image via InfraNet Lab
The recent announcement (via InfraNet Lab) of ‘Ecotone Hydro Park’ by McGill University student Tania Delage uses this theoretical concept of ‘ecotone’, along with Lebbeus Woods’ more politically defined idea of ‘borderline’, “…the site where various systems collide, superimpose, or react to create a new condition,” to develop a proposal for a project in the Great Lakes region.
“At an ecological scale, the site is the Great Lakes basin and Saint-Lawrence River, the largest freshwater system of the world. The watershed is home to many ecological systems and provides important migratory routes for fish that spawn in fresh water only to return to their salt water habitat. Ringed by areas of intense urbanization, the watershed represents a major transportation artery for commercial navigation and provides a source of hydro electric power to the surrounding areas. The waterway also serves as an open sewer to cities along its shore, as it simultaneously supplies their drinking water.”
:: image via InfraNet Lab
“The two water levels present in the site offer opportunities for a changing landscape, atune to the cyclical hydrological variations. Floating filtering gardens, located on the high water level sway back and forth with the currents produced by the dam to reminding visitors of the inner-workings of the facility itself. At the lower water level, an extension of the nature park is created, allowing visitors to experience the filter housing sequence.”
Cool project, great ideas, and simple, effective graphics. Student work is alive and well. Read and see more images at InfraNet Lab, Design Under Sky, Urban Logic, and probably many others. 
:: image via InfraNet Lab