Flooding Effects on the Population Dynamics of Cabomba furcata and Nelumbo nucifera in a Shallow Floodplain Wetland

Abstract

Cabomba furcata is an introduced species that has been naturalized in Malaysia and is becoming invasive in a shallow wetland - Lake Chini, Pahang - displacing the dominance of the native Nelumbo nucifera. The water level structure, which has reduced flooding, plays a vital role in structuring species dominance in this shallow alluvial wetland of the Pahang River floodplain. Biomass sampling focusing on floating-leaved N. nucifera and submerged C. furcata was conducted from September 2009 to March 2011 to determine its association with flooding and season. We found that the non-native C. furcata exhibits no clear seasonal patterns in biomass compared to the native N. nucifera. However, the C. furcata biomass varied with the lake’s water level, which fluctuates with flooding from the Pahang River. High amplitude flooding affected the composition of both C. furcata and N. nucifera. Long-term hydrological and flood data indicate the variability of flooding into the wetland system. The paper concludes by noting the need for concerted sustainable management strategies to be coordinated and managed in addressing Cabomba’s threats.