What are suspended solids in water primarily caused by?

Suspended solids in water are primarily caused by soil erosion because this process involves the detachment and transport of soil particles into water bodies due to factors such as rainfall, wind, or human activities. When soil is eroded, fine particles, including clay, silt, and organic matter, can be washed away and carried into streams, rivers, and lakes, leading to a higher concentration of suspended solids. This not only impacts water clarity but can also affect aquatic ecosystems by smothering habitats and altering the food web.

While other factors like industrial discharge, urban runoff, and certain water treatment processes can contribute to the presence of suspended solids, soil erosion stands out as a natural and significant source, particularly in agricultural areas or regions with disturbed landscapes. Each of these alternatives can certainly introduce pollutants and particulates into water systems, but in terms of natural occurrences and widespread impact, soil erosion is a primary driver.