When household and industrial wastes are disposed into the water, they increase the quantity of germs in it. Germs threaten the health of the organisms living in the water, drinking it or feeding on organisms that live in it. Moreover, huge quantities of nitric and phosphoric salts enter the ecosystem. Phytoplankton, the tiniest sea organisms that can photosynthesize and depend highly on those salts, start to grow in population at top speed, consuming oxygen. As a result, zooplankton which feeds on phytoplankton starts to increase in numbers, again consuming oxygen and producing carbon dioxide.

After some time, during which those small organisms continue to consume oxygen and produce larger amounts of carbon dioxide, there is not enough oxygen to sustain bigger organisms, like fish, who actually die of suffocation.

Lakes are the most usual ecosystems harmed by eutrophication. Oxygen cannot be easily diminished in the sea, and the movement of the water in rivers transfer the salts else where. The most common sign of eutrophication is the waters having a deep green colour. And as human wastes increase, ecosystems become more fragile and their living organisms more vulnerable to suffocation.

Consequently, one of our first priorities, as far as those ecosystems is concerned, is to find alternative ways of removing our industrial and household waste, so that it doesn’t end up in the water. The top priority, needless to say, is to reduce those wastes.

In Madrid, the capital of Spain, a huge structure called the “Air Tree” is currently under construction. It is designed to both affect the surrounding environment and act as a social gathering point for people.

The “Air Tree” will generate its own electricity using solar photo voltaic cells placed on top of it. The solar panels will generate enough electricity to be able to sell the energy to local energy companies.

Inside the structure trees will be planted to produce oxygen, just like an ordinary tree. Due to this the surrounded areas will get a cooler temperature. It is expected that during summers it will be 8-10 °C cooler inside and nearby the “Air Tree”. More trees will be planted around the structure to enhance the cooling effect.

The “Air Tree” will be built with recycled materials and has been co-financed by the Housing and Land of the City Council of Madrid and by the European Union under the LIFE programme-2002 (ENV/E/000198).

You can find more information, in Spanish, and pictures of the “Air Tree” over at Plataforma Arquitectura.