What are macroinvertebrates used for in ecology?

Macroinvertebrates are essential indicators in ecological studies, particularly for assessing water pollution levels. These organisms, which include various species of insects, crustaceans, and mollusks, are sensitive to changes in their environment and can reflect the overall health of aquatic ecosystems. Different species of macroinvertebrates possess varying levels of tolerance to pollutants such as organic waste, heavy metals, and toxic substances. By sampling and identifying these organisms in a water body, ecologists can determine the level of pollution present. A diverse and abundant presence of macroinvertebrates typically indicates good water quality, whereas a dominance of pollution-tolerant species may signal degraded conditions.

The other choices relate to functions that macroinvertebrates do not address directly. For instance, measuring water temperature is typically done with specialized instruments rather than through macroinvertebrate presence. Geological formations are studied through geological surveys and features, while predicting weather patterns relies on meteorological data, not ecological indicators. Hence, macroinvertebrates serve a pivotal role in ecological assessments, particularly in understanding pollution impacts.