An investigation of soil algal abundance using chlorophyll a in a subtropical saltmarsh after surface restoration

The recent listing of saltmarsh in northern New South Wales, Australia, as an endangered ecological community has highlighted the need to rehabilitate damaged saltmarsh and create new areas to offset losses. Land managers require scientific measurements of the early stages of restoration for adaptive management but the interpretation of the data should account for environmental factors. In this study of a degraded and rehabilitated subtropical saltmarsh on the east coast of Australia, measurements of the changes in the soil microalgal community using chlorophyll a showed the differences between reference sites and treatment sites. Analyses of across-site variables showed that solar radiation, rainfall, and tidal inundation influenced microalgal growth, highlighting the importance of seasonal studies. Microalgal abundances showed relationships with developing site variables such as percentage soil moisture, total organic carbon, and total nitrogen. MDS analyses using chlorophyll a showed that the restoration sites were progressing towards, but were not equivalent to the reference state in the short time since restoration (two years) despite the fast growth rates of soil algae.