What does a high JTU in a body of water indicate?

A high JTU (Jackson Turbidity Unit) in a body of water indicates high turbidity, reflecting an increased presence of suspended solids and particulate matter. This can be caused by various factors, such as runoff from the land, erosion, or algal blooms, which reduce the clarity of the water. High turbidity can impact aquatic life by blocking sunlight necessary for photosynthesis, affecting the overall ecosystem health.

In this context, the other options do not accurately describe what high turbidity represents. A low amount of organic matter would typically be associated with lower turbidity, while the presence or absence of bacteria is not directly correlated with turbidity levels. Also, human activities like swimming are not relevant indicators of turbidity. Thus, a high JTU is directly related to the increased turbidity of the water.