Dry weather causes lake to shrink
THE dramatic shrinking of a lake at the Singapore Botanic Gardens on Sunday evening prompted retired civil servant Heng Cho Choon to wonder if the haze had a part to play in the receding water level.
Mr Heng, 70, visits the gardens once a month, and was concerned that the drying up of the lake could have detrimental effects on the plants and wildlife, such as the black swans, there.
"During the rainy season, the lake is typically quite full," he said, adding that the haze and spell of dry weather might have contributed to the water levels.
In response to My Paper queries, Dr Nigel Taylor, director of the Singapore Botanic Gardens, National Parks Board, said that dry weather - but not haze - was indeed to blame for the receded water levels.
He said: "The water levels of our lakes vary depending on weather conditions, and they recede visibly in times of dry weather. The change in water levels is not associated with the haze.
"Our daily checks tell us that the swans have not been affected by the changing water levels."
Associate Professor Matthias Roth, at the National University of Singapore's Department of Geography, said that "a substantial body of water, like a lake, usually won't dry up completely".
When My Paper visited the eco lake in the Bukit Timah core of the gardens yesterday, the water level had risen slightly, thanks to afternoon rain yesterday and on Tuesday.
But the haze can affect plants.
Professor Wong Sek Man from the National University of Singapore's Department of Biological Sciences, who specialises in plant pathology, said compounds found in haze are "as harmful to plants as they are to humans".
"They can cause cell death, which results in wilting, reduction of crop yield and vigour of our greenery," he said.
Prof Wong added that because the intensity and duration of the haze depends on wind direction, it is difficult to pinpoint when these damaging effects might be seen.
"The longer the exposure, the worse the outcome. Some plants are stronger and can withstand more adverse conditions for a longer period of time," he said.
Natural rainfall is the best remedy. But those concerned about their house plants can spray water on them to dilute and wash away haze compounds.
The National Environment Agency has assured that fires causing the haze do not result in toxic rain.