Any particles suspended in the water will increase the scattering of light. In coastal areas, runoff from rivers; resuspension of sand and silt from the bottom by tides, waves, and storms; and a number of other substances can change the color of the near-shore waters. Some types of particles can also contain substances that absorb certain wavelengths of light, which alters its characteristics. For example, microscopic marine algae, called phytoplankton, have the capacity to absorb light in the blue and red region of the spectrum, owing to specific pigments like chlorophyll. Accordingly, as the concentration of phytoplankton increases in the water, the color of the water shifts toward the green part of the spectrum. Fine mineral particles like sediment absorb light in the blue part of the spectrum, causing the water to turn brownish if there is a massive sediment load.