GENERAL REPORT

摘要

Before introducing the subject of the Symposium, it is better to clarify the difference betweenpoint source and non-point source pollution (NPS). Point source and NPS differ in the scaleof the areal extent of their source. NPS is a terrestrial system refers “to those contaminantsin surface and subsurface soil and water resources that are diffused, or rather, are spreadover large area” (Corwin, 1996). NPS cannot be traced to a point location or source. Incontrast, point source pollutants are connected with a point location and are generally highlytoxic resulting in acute toxicity. On the other hand the point source pollutants are identifi ableand more easily controlled than NPS. Non-point sources pollutants are a consequence ofagricultural activities, industrial and urban runoff, mining and forest harvesting activities,path salt runoff, atmospheric deposition, and hydrological modifi cation i.e., diversion, dam,over pumping of groundwater etc. On the contrary point sources include hazardous wastespills, industrial or municipal wastewater outfalls, deep-well waste disposal, municipal andhazardous waste dump sites etc. Again the difference between point source and NPS areoften blurred by the scale reference.