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Vegetation canopies represent the main ecosystems on intertidal landforms and they
clearly respond to changes in coastal environments. Climate change, including temperature,
precipitation and sea level rise, are affecting the health and distribution of coastal vegetation, as well
as the runoff and sedimentation rates that can impact coastal areas. This study has used the
normalized difference vegetation index (NDVI) to investigate vegetation canopy dynamics on three
different coastal sites in southeastern Australia over the past 47 years (1975 2015). NDVIs
temporal-datasets have been built from satellite images derived from Landsat 1 8. These were then
regressed to the climatic and geomorphic variables. Results show clear increases in NDVI at
Towamba and Wandandian Estuaries, but a decline at Comerong Island (southeastern Australia). The
sedimentation rate has the most significant positive impact on NDVI since it has the potential to
provide additional space for vegetation. Temperature and sea level rise have positive effects, except
on Comerong Island, but rainfall has no significant effect on the NDVI at any site. Different NDVI
trends have been recorded at these three coastal sites reflecting different correlations between the
vegetation, climatic and geomorphic (as independent) variables. The geomorphological
characteristics of the highly-dynamic intertidal estuarine landforms, which are subject to active
erosion and deposition processes, have the largest impact on vegetation cover and, hence, on NDVI.
Assessing the vegetation canopy using NDVI as an evaluation tool has provided temporal-dynamic
datasets that can be correlated to the main individual environmental controls. Such knowledge will
allow resource managers to make more informed decisions for sustainable conservation plans
following the evaluation the potential consequences of any environmental changes.