Valentine's Day threatens the planet's ecology, says a recent study. Roses sold during Valentine's Day in the uk are being grown at the cost of the ecology of Kenya's Lake Naivasha, says David Harper, an ecologist at the University of Leicester.

Horticulture has long been a booming trade on the shores of the lake. But increasingly more and more people are migrating to the lake to make a living with the present population being almost half a million. The pressure of the increasing population on the lake is destroying it, Harper argues.

Sanitation is a major issue with water being drawn from the lake and sewage flowing back into the lake. Harper and his colleagues are working towards raising money for the restoration of the lake.