截污工程完成后武汉东湖自然净化速率探讨

根据几十年来武汉东湖水质监测资料和数据 ,在东湖截污工程完成后 ,没有新的污染物进入水体的前提下 ,对东湖水体通过自然净化恢复到健康状态所需要的时间进行了详细的数学推导和科学论证。结果表明 ,在不考虑地泥营养物质的情况下 ,东湖水体通过工业、农业、生活用水以及收获鱼类和高等植物造成的营养物的输出 ,只需要 3a左右的时间就能恢复。然而如果考虑地泥的影响 ,几十年沉积在地泥的营养物质持续向水体中释放 ,然后再通过用水及生物输出 ,东湖水质需要35a以上才能得到恢复。可见 ,截污后东湖在相当长的时间内还将处于富营养化状态 ,地泥是造成东湖长期富营养化的关键。解决东湖污染问题的关键是清除地泥 ,因此得出结论 :挖底泥后引入长江水源来加速东湖水体改善的最佳途径

NATURAL PURIFICATION RATE OF LAKE DONGHU IN WUHAN AFTER POLLUTION-CUTTING ENGINEERING

According to the water quality data obtained in monitoring Lake Donghu for several decades, the detailed deduce and scientific demonstration of the restoring rate of Lake Donghu with the natural purification is conducted by authors in the premise that no new pollutants get into the lake after the pollution-cutting engineering. The results show that it needs about only 3 years for the restoration by the nutrient substance outputting with the water usage of industry, agriculture, people and the yielding of fish and advance plant without regarding of the substrate sludge. But once regarding of the releasing of the nutrient substance deposited in the substrate sludge for several decades and the output by water usage and biological yielding, it will be take about 35 years for the water restoration. This shows that the water of the lake will be in the condition of eutrophication for a long time after purification cutting engineering. The substrate sludge is the main factor causing eutrophication and the key of resolving the pollution problem of the lake is the clearing of substrate sludge. Hence it is concluded that it should be necessary to dig the bottom mud and draw the water of Changjiang River into Lake Donghu in order to accelerate the improvement of the water quality.