Which factor can contribute to the presence of impurities in water bodies?

Land erosion significantly contributes to the presence of impurities in water bodies. When soil and other materials are eroded from the land, they are often washed into nearby streams, rivers, and lakes. This process introduces contaminants such as sediments, organic material, and potentially harmful pollutants into the water. The particles transported by erosion can carry fertilizers, pesticides, and various chemicals that were applied to the land, increasing the impurity levels in the water.

Natural mineral deposits can also affect water quality, but they typically do so in a more stable and localized manner. Meanwhile, increasing water levels can dilute concentrations of impurities but do not inherently introduce new impurities. Enhanced filtration methods are designed to remove contaminants and improve water quality rather than contribute to impurity levels.