ABSTRACT
The wetland ecosystems of tropical Australia constitute a range of habitats progressing inland from coastal mangroves and seagrass beds to estuarine deltas, riparian swamps, marshes and extensive floodplains, many of them afforded special conservation status. Floodplain wetlands of the northern region typically experience an annual wet–dry cycle driven by the monsoonal rainfall pattern. One of the most distinctive features of the water resource of the tropical north is that despite its abundance its availability to support both natural and developed ecosystems is extremely variable, both geographically and seasonally. Farm dams represent a critical form of infrastructure supporting stock and domestic watering as well as limited crop irrigation. The biota of billabongs and other small and often temporary impoundments are regularly subject to extreme conditions such as recurring diurnal periods of hypoxia. Mangroves are likely to be particularly affected by sea-level rises and by climatic variations.
