Architecture is both the process and the product of planning, designing, and constructing buildings or any other structures. Architectural works, in the material form of buildings, are often perceived as cultural symbols and as works of art. Historical civilizations are often identified with their surviving architectural achievements.
Architects and engineers are among the most fortunate of men since they build their own monuments with public consent, public approval and often public money.
Like all ecosystems on Earth supporting animal and plant life, aquatic ecosystems need oxygen. However, oxygen availability in these systems is threatened by global warming and excessive input of nutrients such as from agriculture and wastewaters, known as eutrophication.