基于GIS的考洲洋养殖水域水质状况分析

Analysis of water quality status in culturing waters in Kaozhou Bay based upon GIS

在GIS和数据库技术的支持下,据1999年2月(枯水期)和8月(丰水期)两个航次的调查数据,利用数据插值和栅格图形加权平均等处理手段,综合分析和评价了考洲洋水域的水质营养状况。结果显示,枯水期考洲洋的水质符合一类海水水质标准,整个水域未受明显有机污染,丰水期整个水域符合二类海水水质标准,湾西北部和吉隆河口附近水域受明显的有机污染,出现富营养化现象,应引起重视。两个调查航次初级生产力的分布趋势相似,均呈现湾口高,湾中部和湾西北部低的变化趋势。饵料生物的分布无明显的规律,在枯水期,饵料生物的分布较为均匀,大部分水域处于2～3级水平,其密集分布区出现在湾西北部、湾口和吉隆河口附近水域,而在丰水期,饵料生物的变化幅度较大,其密集分布区位于湾中部水域和望京洲沿岸水域。两个航次相比,丰水期的初级生产力水平和饵料生物水平均高于枯水期。

Supported by the technique of GIS and database and based on the survey data of two cruises in February (dry season) and August (wet season) of 1999, this paper analyzed and evaluated comprehensively the status of water nutrient in Kaozhou Bay by using the method of data interpolation and grid weighting scheme. In the dry season, the water quality accorded with the first class of sea water standard without any organic pollution, while in the wet season it was in the second class with obvious organic pollution and eutrophication occurring in the northwestern waters and the estuary of Jilong River. The distribution trends of the primary productivity were similar in the two surveys, which were high in the mouth of the bay and low in the middle and northwestern waters. The distributions of the food organisms were irregular in both of the surveys. In the dry season they were evenly distributed with most of the waters belonging to the second or the third level, and the dense area was found in the northwestern waters, the mouth of the bay and the waters around Jilong River, while in the wet season, the food organism level varied distinctly with the dense area occurring in the middle waters of the bay and the coastal waters along Wangjingzhou village. Compared between the two surveys, the levels of primary productivity and food organisms in the wet season were higher than those in the dry season.