Effects of large-area planting water hyacinth (Eichhornia crassipes) on water quality in the bay of Lake Dianchi
滇池湖湾大水域种养水葫芦对水质的影响分析

To evaluate the effects of large-area planting water hyacinth (Eichhornia crassipes) on water quality in the bay of Lake Dianchi, consecutive water sampling investigations in the planting, near-planting and far-planting areas of water hyacinth were carried out from August to October 2010. Results showed that total phosphorus, total nitrogen and permanganate index in the water of the planting areas increased since mid-September. Compared with near-planting and far-planting areas, dissolve oxygen and pH in planting area significant decreased, but the dissolved oxygen remained at high levels; however, total phosphorus, total nitrogen and permanganate index obviously increased. The water transparency in the near-planting area was higher than those in the planting and far-planting areas, and total phosphorus, orthophosphate, total nitrogen and chlorophyll-a were lower than those in the planting and far-planting areas, showing that the water quality was improved in the near-planting area.