Mr John Tan, sponsor of the Tan Teck Guan Medal, will present the award to Dr Sasi Nayar for his 2003 doctoral thesis on pollutants in the Punggol River. This will be followed by Dr Sasi’s talk on his current research in Adelaide: “What Killed The Seagrasses Off The Adelaide Coast In Southern Australia?”
Since the 1940s,over 5000ha of near-shore meadow-forming seagrasses, Amphibolis and Posidonia, have been lost from Adelaide’s metropolitan coastline in Southern Australia. The loss of these seagrasses is a major concern due to their importance to near-shore productivity, seabed stability and biodiversity. Engineering works and urbanisation during the 20th century
Substantially increased water flow to the coast from rivers, stormwater drains, and wastewater treatment plant discharges, sullying the metropolitan coast. Elevated levels of nutrients, toxicants and turbidity have been detected and reported regularly over the last 30 years.Each of these potential stressors has been implicated in the historical loss of seagrasses. This talk will specifically address the effect of nutrients on seagrass assessed from in-situ chamber incubations, field experiments and mesocosm (simulation of real-life conditions) trials. The presentation and talk will take place from 7pm to 9pm in the Gardens Briefing Room (next to the Botanic Gardens Shop) at the Botanic Gardens Visitor Centre (at the junction of Cluny and Nassim Roads).