Abstract:
A study on temporal variation and behavior of phosphorus and nitrogen in Bangpakong estuary (11 station) was carried out from April-December 2002. It was found that phosphorus had no conservative behavior. Quantities of phosphorus changed according to time and places (stations) by increasing dissolution in water during the rainy season and decreasing in dry season. Quantities of phosphorus tended to change according to time and places (stations) with increasing dissolved portion in the rainy season and decreasing dissolved portion in the dry season. Quantities of phosphorus in estuarine sediments were in a regular distribution. Whereas suspended phosphorus distribution in rainy season was higher in the dry season. Moreover, quantities of dissolved, sedimentary and suspended phosphorus showed higher trends in central part of the river and were lower along the distance from the estuary to the sea. Nitrogen in the Bangpakong estuary had no conservative behavior the sane phosphorus. Major forms of quantitative dissolved nitrogen were nitrate, ammonia and nitrite respectively. Quantities of nitrogen showed temporal variation with stations (place). Namely, quantities of nitrogen tented to be lower at stations far from the river to the sea. In addition, it was found that quantities of phosphorus, nitrite and nitrate showed relationship with quantities of suspended portions. Quantities of phosphorus revealed trend to relation with pH while also ammonia and nitrate revealed trend in with salinity of the river water.