三门湾健跳网箱养鱼区营养盐的变化及水质现状评价

Change of Nutrients and Present Evaluation of Water Quality in the Cage Fish Culture Region of Jiantiao at Sanmen Bay

利用2002年8月至2003年7月的调查资料,分析讨论了三门湾健跳网箱养鱼区营养盐的变化,并对其水质现状进行了评价,结果表明:鱼排外与网箱内的水质参数全年平均值差异不大。PO43--P浓度在6月和9月最高,接近三类水质标准;DIN浓度2月和9月严重超标,其它月份三类水质占56．7％,四类水质占43_3％。8月养殖区NO2--N浓度的日变化规律表现为高潮时低,低潮时高,潮汐周期明显;其它营养盐浓度的日变化规律不明显。该网箱养鱼区水质总体上属于轻度污染,且基本处于富营养化状态。

Based on the data collected from August 2002 to July 2003 at Sanmen bay, analysis and discussion of the nutrient change in the cage fish Culture region of Jiantiao have been made as well as the evaluation of present water quality. The result showed that there were no obvious difference in the average parameters of water quality inside and outside the cage all the year. The highest concentration of PO4^3--Poccurring in June and September were near the third grade water quality standard. The concentration of DIN in February and September exceeded severelythe standard. In other months the third grade Water quality took 56.7 % and fourth grade 43.3 %. In August the daily concentration of NO^2--N varied regularly, wie low values in high tide and high values in low tide, and the tide cycle is obvious while others irregular. As a whole, the pollution level in this area was slight but the water quality was overnourishous.