The lack of viable forest areas means less oxygen production and massive soil erosion (as tree roots play a major part n anchoring soil). Elephants need vast areas of fertile land and forests in which to graze. As they tear and push down trees, they now begin to exacerbate the man-made problem as there are insufficient resources.
In third-world continents, such as Africa and Asia (where elephants are common), overgrazing is a growing epidemic. Grazing livestock has completely destroyed the land and its nutrients, rendering it completely barren. As this problem spreads over increased farming areas, the space available to wildlife decreases exponentially. With elephants requiring as much vegetation as they do, these areas are completely useless to them.
As is the nature with the human race, hunting has been carried out in absolute excess. Elephants themselves are hunted for their ivory and hides. Over Hunting is considerably easier in the case of an elephant because its lifespan is longer and they take many years to reach maturity. This means that the population is not able to regenerate as quickly or as easily as species that reach maturity faster and produce more offspring more regularly.
As other animals are killed at an alarming rate, the effects ripple up the food chain and affect all of the links in that chain. Ironically, it also has major repercussions on man, who perch at the top of that chain. However, these repercussions are yet to prevent humans from their relentless destruction.
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