it's a measure of how far down light can penetrate through the water column. ... Because water clarity is closely related to light penetration, it has important implications for the diversity and productivity of aquatic life that a system can support
Water clarity is a measure of how far down light can penetrate through the water. The clearer the water is the farther light can go down. This is important because with water clarity we can find out how much living things that part of the water can support. Clearer water allows light to reach farther down, which can allow aquatic plants to grow deeper in the water.
