Answer:
fertile soil
Explanation:
The environmental problems have numerous sources, and all of them combined manage to create a real environmental chaos and even a total disaster.
The deserts for example are always an environmental problem. The reason for it is that they tend to expand. That process is known as desertification. The desert wind manage to influence the surrounding areas, dry them out, and also move layers of sand on top of them, gradually turning them into deserts as well.
The oil resources cause big environmental problems everywhere they are found and extracted. The reason for this is that the extraction of the oil is done with methods that directly kill off or badly damage the living organisms. Also, the oil spills are common, and they are able to kill everything that comes in contact with them.
The water scarcity too is a major environmental problem. The reason for this is very simple - every living organism needs water to survive, so without it the environment suffers badly.
The fertile soils are a positive for the environment though. They give the basis and nutrients for the flora to develop, and after the flora is in place, the fauna follows, so the environment prospers.
