The cities play a central role in the development process. Like place of population increase, commercial and industrial activity, the cities concentrate the use of energy and resources and the generation of wastes to the point in which the artificial systems as as much natural are overloaded and the capacities to handle them are crushed.
The resulting damages or environmental costs put in dangerthe future productivity of the cities and the health and quality of life of their citizens. The cities have become the main environmental red zones that they urgently require of special attention in the regional environmental evaluations and from project and in the planning and environmental administration to metropolitan regional scale.
The sweepings is a great problem that also affects to theanimals in extinction. It learns about which there is in your sweepings stock market and what you can make not to contaminate so much. The sweepings is a great problem that also affects to the animals in extinction. It learns about which there is in your sweepings stock market and what you can make not to contaminate so much. One of the main world-wide ecological problems is the climatic change,is the effect conservatory «like result of activities such as the fossil fuel use, the deforestation on great scale and the fast expansion of the irrigable agriculture contamination of the air. Many of the organisms and associated biological processes to the diffusion of the infectious diseases depend specially on the climatic variables, mainly of the temperature, precipitations and of humedadOtroimportant effect of the climatic change is the increase of the episodes of atmospheric contamination

Weakening of the ozone layer Deforestation the consequences of the destruction of the arboreal layer worldwide constitutes a serious problem with multiple consequences. Within the effects one is: the reduction of the general productivity of the zone, the ground is more subject to the erosion,alters the hidrológico cycle, the biodiversity diminishes largely and to the reserves of nutrients and biomass before stored in the rest of trees are reduced and leaves. Contamination the poisonous effects of some polluting agents that we threw in the atmosphere accumulate and affect the individual, to the community and even to the ecosystems, altering not only the physical part but also the geneticinformation of the populations. The effects of the contamination also damage the atmosphere because polluting particle overload

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The marine seals and elephants are mammals that pass most of thetime in the oceans. They are more common in the Arctic zones and Antarctic although some species live in the tropical seas. It had once, yes already is only a story, a species of seal that lived in the Caribbean, to which the books talk about by Foca of the Caribbean, Monachus tropicalis. The seals easily distinguish of the marine lions and marine bears in which these others have external ears.The seals only exhibit an orifice. Other differences in the anatomy exist but more they are detailed and not so easy to appreciate at first. Morsa is greater than the seals and has two great eyeteeth. The marine elephants, that are near relatives affluent of the seal and are including in the same family who the seals, are gigantic. Characteristic of the seals it is the ability to move the tailforwards. When they are outside the water it they can put the body underneath. Experts in this species indicate abundant evidences that demonstrate that the hunting is not sustainable, since the ice cover of the Atlantic coast, where the young is born, is more and more weak and exist tests that the index of mortality of the seals increases. But in addition, cruelty towards life wild, as much if it…