Water diversion and irrigation has allowed humans to grow crops in areas where natural supplies have been limited. A major challenge that exists in these regions has been . salinization of soils low crop diversity soil erosion high pesticide use high trophic-level efficiency

Elephants in the savanna regions of africa dig holes in dried up river beds to reach water lying just below the surface. these holes provide drinking water for other animals as well. so, without the elephants, many animals might otherwise die from lack of water during the dry season. the location in which the elephants live is an example of a/n and the role they play in creating water holes is an example of a a) ecosystem; habitat b) community; niche c) habitat; niche d) niche; habitat