What does eutrophication refer to in water bodies?

Eutrophication refers to the process in which water bodies become enriched with nutrients, particularly phosphorus and nitrogen, leading to excessive growth of algae. This phenomenon often occurs as a result of runoff from fertilized agricultural land, wastewater discharge, and other sources of nutrient pollution. The rapid increase in algae can deplete oxygen levels in the water, creating dead zones that are detrimental to aquatic life. Overall, eutrophication is characterized by the imbalance it introduces in an ecosystem, leading to degradation of water quality and biodiversity.

The other options do not accurately describe eutrophication. Improving biodiversity usually represents a healthy ecosystem, which contrasts with the adverse effects of eutrophication. A reduction of dissolved solids does not relate to the nutrient enrichment that drives algal blooms. Likewise, an increase in water temperature can exacerbate the conditions for eutrophication but is not the definition of the process itself. Thus, the correct understanding of eutrophication is rooted in the context of nutrient enrichment and its ecological consequences.