What foram evidence might indicate heavy metal pollution?
One factor to look for is the presence of “opportunistic” taxa. Scientists have learned in previous studies, which groups of species are more likely to be present when water quality begins to degrade. These groups are called “opportunistic”, meaning that they move into an area when other species can’t tolerate the conditions and move out. The presence of opportunistic taxa is a clear sign that something is creating stress, but it does not necessarily prove that the problem is heavy metal contamination. Stress may be due to variable salinity, low oxygen, the presence of pollutants or a combination of all three. See some examples below of opportunistic taxa. In addition, forams exposed to heavy metal pollution often show test deformities. However, test deformities may also occur as a result of physical stress, such as living in an area with active water movement which can crack or break tests. In these cases, the repaired test may also look deformed. So test deformities are not automatic
