What phenomenon occurs due to temperature differences in water layers, resulting in oxygen depletion?

The phenomenon that results from temperature differences in water layers, leading to oxygen depletion, is known as water stratification. Water stratification refers to the layering of water in a body of water, such as a lake or reservoir, where different layers have distinct temperatures. Typically, warmer water is found at the surface while cooler water resides at greater depths.

As temperatures stratify, the upper layers can become insulated from the lower layers, preventing mixing. This lack of mixing can trap nutrients and organic materials in the lower layers where decomposition occurs, consuming the available oxygen. As a result, oxygen levels can diminish in the deeper, cooler layers, leading to hypoxic conditions or even anoxic conditions, which negatively affect aquatic life.

The other options relate to different processes or phenomena. Lake turnover involves the mixing of the water layers during seasonal changes, which can distribute oxygen and nutrients. Thermal inversion is a meteorological phenomenon, not directly related to water layers in lakes. Groundwater recharge describes the process by which groundwater is replenished, unrelated to the layering or oxygen dynamics of surface water.