Eutrophication is a process that leads to enrichment of ponds, lakes and any water body with minerals such as nitrogen and phosphorus. Aquatic ecosystems are diverse and consists of phytoplanktons, zooplanktons, fish and other animals. Too much enrichment of the ecosystem adversely effects the flora and fauna of the aquatic bodies. Eutrophication leads to more uptake of oxygen and increases biological oxygen demand of water. With less oxygen available for animals inside the aquatic systems, they might began to die. Eutrophication is a result of human activities and must be minimized for the betterment of aquatic bodies and aquatic animals. Thus, eutrophication might lead to destroy the aquatic bodies over a period of time.
Answer should be Achilles tendon
<span>Studying the changes in densities of pocket gophers when large herbivores such as elk are excluded from mountain forests would be an example of studying ecology at the community level.
A community refers to a group of organisms of various species that live in the same location and interact with each other. So, if this scientist is observing gophers and elks, they are looking at the level of communities, not anything more or less.
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