日本Kojima湖的富营养化

日本Kojima湖现在每年的COD平均浓度大约是10mg/L，这是日本环境标准的两倍。COD颗粒的浓度被确定是与叶绿素a的浓度成比例的。另一方面，溶解COD的浓度与叶绿素a的浓度无关。因此，COD颗粒显然是被水藻增长引起的。此外，估计与Kojima湖富营养化相关的内部产物导致的COD的百分比是总COD的20％－30％。

CULTURAL EUTROPHICATION OF KOJIMA LAKE, JAPAN

The current annual average COD concentration in Kojima Lake, Japan is about 10 mg/L, which is twice that of the Japanese Environmental Standard. The concentration of particulate COD (p- COD) was determined to be proportional to the concentration of chlorophyll a. On the other hand, the concentration of dissolved COD was independent of chlorophyll a concentration. Hence, p- COD is apparently caused by algal growth. Moreover, the percentage of COD due to eutrophication - related internal production in Kojima Lake was estimated to be 20% ～ 30% of the total COD.