trinity of principles(trias of environmental policy principles: precautionary, originator (polluter-pays) and cooperation principle; Three fundamental principles of environmental policy: precautionary principle, polluter pays-principle and cooperation principle)
trophic ecology(The study of the feeding relationships of organisms in communities and ecosystems. Trophic links between populations represent flows of organisms, organic energy and nutrients. Trophic transfers are important in population dynamics, biogeochemistry, and ecosystem energetics)