Inundation of saline supratidal mudflats provides an important source of carbon and nutrients in an aquatic system

Assessment of water quality from the Normanby River catchment to coastal flood plumes on the northern Great Barrier Reef, Australia

“…Alongi and McKinnon (2005) showed that PCB intertidal mudflats release NH 4 to the water column in the order of 950 mmol N m À2 day À1 under non-event conditions. Other potential coastal sources of NH 4 include waters draining from inundated freshwater flood plains, supratidal mudflats (Burford et al 2016), the flux of NH 4 from mangrove sediment porewaters (Dittmar and Lara 2001), ammonification of particulate organic nitrogen (PON), remineralisation from DON and dissimilatory nitrate reduction to ammonium (DNRA) by anaerobic bacteria in sediments or the water column (Dagg et al 2004). Davies and Eyre (2005) also found NH 4 increased near the mouths of the Annan and Daintree rivers (northern GBR) during flood events, which they associated with the flushing of mangrove channels or the decomposition of PON.…”

Controls on Carbon, Nutrient, and Sediment Cycling in a Large, Semiarid Estuarine System; Princess Charlotte Bay, Australia

“…Repeated cycles of sediment resuspension and deposition can enhance degradation of OM and release nutrients but can also inhibit primary production through light limitation (Burford et al, ; Radke et al, ). Salt flats surrounding semiarid estuaries have been reported as both nutrient sources (Ridd et al, , ) and sinks (Burford et al, , ), and similar variability has been documented for mangroves (Sippo et al, ). Coupled seasonal forcing can act to trap material in some estuaries (Bryce et al, , ), efficiently export material from others (Larcombe & Woolfe, ), or vary between the two on interannual scales (Webster & Ford, ; Wolanski et al, ).…”

Predicting hot spots of aquatic plant biomass in a large floodplain river catchment in the Australian wet-dry tropics

“…In a study conducted on the Cloncurry River in the Flinders catchment, land surface conditions such as evaporation affected water storage volumes in water holes, which in turn influenced the production of phytoplankton biomass (see, Faggotter et al, 2013). While the importance of inundation extent in driving the rates of aquatic primary producers in shallow coastal habitats of wet-dry tropics of Australia have been identified (Burford et al, 2016), others have noted the key implications of dynamics in surface water resources and wetland connectivity for aquatic biota (e.g., Ward et al, 2013;Karim et al, 2012;Bunn et al, 2006). In addition to the aforementioned reports, contrasting conclusions in some locationspecific studies regarding drivers of phytoplankton biomass and productivity and aquatic food web within these freshwater systems (e.g., Faggotter et al, 2013;Burford et al, 2012;Bunn et al, 2003) are also noted, warranting large scale assessments of floodplain inundation and the distribution of aquatic plant biomass.…”

“…These characteristics underpin knowledge on the impacts of climate change and/or anthropogenic influence on the distribution of primary production in aquatic systems within wet-dry tropical systems. Isolated and discreet water holes within these systems have been identified as highly productive centers in terms of phytoplankton biomass production, macrophyte, periphyton and other primary producers that generate biomass for secondary aquatic producers (e.g., Burford et al, 2016;Ward et al, 2016;Waltham et al, 2013;Faggotter et al, 2013).…”

“…While inundation extent in saline supratidal mudflats in wet-dry tropical regions of Australia was found to be an important indicator for the rates of primary productivity (see, Burford et al, 2016), the vulnerability of freshwater systems and aquatic habitats to climate influence and changes in human-water policies and management are strong motivations warranting large-scale assessments. In addition to this, the variability in reflectance values of aquatic vegetation caused by poor discrimination of aquatic plants from water signals in Lakes, especially during flood periods, and the limitations of the near-infrared wavelength in aquatic plant biomass prediction (e.g., Chen et al, 2018;Davranche et al, 2010;Cho et al, 2008;Silva et al, 2008;Malthus and George, 1997) have been reported.…”