Water Pollution and Control in Agriculture
Hydrologic Cycle important in understanding transport of contaminants via water and soil (soil
type – sand, silt, clay ratio, vegetation, organic material, moisture content of soil, and slope) and
intensity of rainfall. Surface runoff and water moving through the soil profile are key factors in
transportation of pollutants.
Only 2.5% of global water is freshwater. Of that 2.5% only 0.3% is renewable in freshwater
lakes and rivers. Only 30% of the 2.5% is accessible (groundwater).
Future reduced available water per capita due to raising population numbers is likely to be
coupled with reduced water quality. Microorganisms (parasites, bacteria, viruses), nutrients
(nitrates, phosphorus), metals (As, Cd, Hg, Pb, Cu, Ni,Zn), and synthetic compounds
(pesticides, effluents, hormones, steroids) threaten water quality.
Contaminations: boaters, tourism, industrial, urban runoff, landfills, municipal water supply