millions of fish die, page-11

Thanks for the reply ptygmit.

And what causes algal blooms ? It can be triggered by man-made pollutants containing phosphorus and nitrogen, can it not ?

"Runoff and erosion from fertilised agricultural areas, erosion from river banks, river beds, land clearing (deforestation), and sewage effluent are the major sources of phosphorus and nitrogen entering water ways"

http://www.water.nsw.gov.au/Water-Management/Water-quality/Algal-information/What-causes-algal-blooms/What-causes-algal-blooms/default.aspx