Sustainable Management of Lakes and Estuarine Ecosystems to Overcome Catastrophic Regime Shifts

Project Leader: Prof Koh Hock Lye

Lakes, rivers and estuaries provide essential services to ecosystems, wildlife and human. The economic-ecosystem service value of a given lake or estuary is contingent on its water quality and trophic status. The current water quality status of many urban lakes, rivers and estuaries in Malaysia is Class III and is rated as eutrophic. Given the projected increase in urban population and intensifying land-use surrounding urban lakes and estuaries and given the unabated accumulation of nutrients in the lake sediments, a prognosis is that all lakes, including Sunway Lagoon (SL) and lakes within the Putrajaya district, are threatened by regime shift to eutrophication (Koh et al., 2018 a). The primary goal is to maximize ecosystem- social-economic value of lakes, rivers and estuaries. This project has achieved the goal of rehabilitating SL (Koh et al., 2018 b) and aims to extend the application to other urban lakes and estuaries including those in Putrajaya and Iskandar Johor. Without proper water quality management, lakes and estuarine water may over time approach an irreversible and costly hyper-eutrophication threshold. The abrupt regime shift (bifurcation tipping) from a eutrophic to a hyper-eutrophic condition can be rapid once the critical threshold is reached. This regime shift can be delayed or prevented by proper lake water quality management that utilizes low-resource and low-carbon methodology and technology (Koh et al., 2018 c). This project has developed methodology and simulation models (Figure 1) for the analysis, synthesis, prognosis and management of lake and estuarine ecosystems. This research will address SDG 6 (Clean Water and Sanitation), SDG 11 (Sustainable Cities and Communities), SDG 13 (Climate Action) and SDG 14 (Life Below Water).

Publications:

  • Koh, H.L., Tan, W.K. and Teh, S.Y. (2018a). Regime Shift Analysis and Numerical Simulation for Effective Ecosystem Management. International Journal of Environmental Science and Development 9(8), 192-199. DOI: 10.18178/ijesd.2018.9.8.1099 (Indexed by Chemical Abstracts Services (CAS), CABI, DOAJ, Ulrich Periodicals Directory, Engineering & Technology Digital Library, Electronic Journals Library, Crossref, ProQuest). Best paper.
  • Koh, H.L., Teh, S.Y., Lee, E., Tan, W.K., Sagathevan, K.A. and Low, A.A. (2018b). Derivation of optimal fish stocking density via simulation of water quality model E2Algae. AIP Conference Proceedings 1974, 020042. DOI: 10.1063/1.5041573 (ISI Proceedings).
  • Koh, H.L., Teh, S.Y. and Tan, W.K. (2018c). Water Quality Simulation for Rehabilitation of a Eutrophic Lake in Selangor Malaysia. International Conference on Ecology and Biodiversity Across Time and Space (ICEBATS2018), 15-17 August 2018, Universti Sains Malaysia, Penang, Malaysia. Submitted to journal publication; under review.