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Coastal wetlands are globally important ecosystems, valued for their provision of habitat, storm mitigation, water quality improvement, and carbon sequestration. Coastal wetlands are also one of the ecosystems most likely to be impacted by projected changes in climate, particularly changes associated with sea level rise, altered rainfall patterns, and changes to storm patterns and severity. Coastal freshwater wetlands (CFWs) are amongst the most understudied group of coastal wetlands and are characterised by freshwater dominated hydrology but can also experience periods of salinity associated with their proximity to the coast (i.e. as the result of storm surge and spring high tides). CFWs commonly occur as the most landward of coastal wetlands and many adjoin urban development, exposing them to anthropogenic impacts (nutrient enrichment, clearing, hydrology alteration). This position in the coastal landscape makes CFWs highly susceptible to salinity stress, particularly climate change induced sea level rise. Research investigating CFWs, their ecology, and responses to climate change threats, is greatly lacking, particularly for areas outside the United States of America (USA). This thesis investigates the resilience of CFWs to climate change and aims to address significant knowledge gaps by investigating: 1) the current knowledge of CFW responses to projected climate change globally�� 2) the structure and composition of CFW vegetation in southeast Queensland and exploring drivers of vegetation patterns�� 3) the role of soil seed banks in vegetation resilience for CFWs in southeast Queensland through contributions to vegetation dynamics�� and 4) the regenerative potential and responses of CFW vegetation communities to altered hydrology and salinity regimes simulating sea level rise. To begin, I synthesised the current knowledge of CFW responses to projected changes in climate globally, through a systematic quantitative literature review, with the aim of identifying key knowledge gaps regarding geographic locations and research areas, with particular focus on four key aspects of climate change: sea level rise, altered rainfall, extreme events, increased temperature, and greenhouse gases. In Chapter 2, I reviewed published research on responses of CFWs in observational, experimental, and modelling studies within those four key aspects of climate change. This review identified that, despite the increasing research interest, knowledge of all aspects of climate change is lacking, particularly outside of the USA. Within the USA, while there is a significant body of research exploring the response of CFWs to impacts associated with rising sea levels, changes to rainfall patterns, and extreme events, the impacts of temperature and greenhouse gases remain unknown globally. Importantly, research investigating the response of CFWs to multiple climate drivers was identified as a significant knowledge gap.The research then focused on field and greenhouse studies of CFW vegetation communities in southeast Queensland, Australia to expand the knowledge of CFWs outside of the USA. Chapters 3 and 4 explored patterns in standing and soil seed bank vegetation assemblages and provides a baseline understanding of the structure and composition of these vegetation communities. In addition, I assessed local and regional environmental drivers (i.e. local hydrology, soil salinity, local land uses, projected sea level rise extent) of vegetation patterns and discussed potential changes to these drivers with climate change. To explore the effects of sea level rise on ground in CFWs, I conducted an in-situ hydrology and salinity manipulation experiment at an abandoned sugarcane farm which has a regenerating CFW vegetation community (Chapter 5). CFWs in southeast Queensland are important for their roles in nutrient cycling and habitat provision for endangered fauna species. My assessment of these vegetation communities (Chapter 3) also highlights that CFWs are home to a diverse vegetation assemblage including at least two flora species of national significance, flagging the biodiversity importance of these isolated wetland patches within a developed coastal landscape. Species composition was distinct between vegetation patches and a large proportion of variation between sites was associated with differences in local hydrology and salinity influence. The importance of hydrology and salinity as drivers of vegetation patterns suggests that climate change could dramatically impact the structure and composition of CFWs. The ability of CFWs to be maintained in the landscape under a changing climate is influenced by their regenerative capacity from soil seed banks or other propagule banks. In Chapter 4, I assessed the composition of CFW soil seed banks and explored potential drivers of vegetation patterns. Through this study, I again found that hydrology and salinity were strong drivers of patterns in soil seed bank composition, as well as, local land use which was associated with the proportion of exotic species. Similarity of soil seed banks to standing vegetation was low, suggesting that soil seed banks have a minimal role in maintaining standing vegetation communities in southeast Queensland CFWs. Rather, soil seed banks could provide a mechanism for vegetation change along four possible trajectories depending on the soil seed bank composition and abiotic conditions. Hydrology and salinity are important drivers of CFW vegetation composition identified in this thesis. In Chapter 5, I explored the impacts of altered hydrology and salinity regimes on CFW vegetation communities regenerating on abandoned agricultural land. Change in vegetation composition and structure was assessed in-situ at Yandina Creek Wetlands (YCW) where vegetation has naturally regenerated into communities typical of CFWs in southeast Queensland during 15 years since abandoment of sugarcane production. This regeneration potential is important given the projected constriction of CFWs between migrating seaward Changes were varied in each habitat surveyed, however, reductions in vegetation cover and species richness were observed over time in response to altered conditions in freshwater habitats. Conversely, vegetation cover increased in the saltmarsh, suggesting that this community is tolerant of the altered conditions and may expand within YCW. The changes observed at YCW suggest that widespread change is likely for many CFWs with increasing sea levels, but careful management could aid in maintaining these ecosystems in the coastal landscape. Overall, this thesis significantly furthers the understanding of CFWs and their vegetation patterns outside of the USA, and explores the future of these systems with climate change in southeast Queensland, Australia. The findings of this thesis highlight the importance of hydrology and salinity as drivers of vegetation patterns and indicates that dramatic and potentially rapid change in vegetation structure and composition will occur as a result of climate change. CFWs in southeast Queensland are important and highly variable vegetation communities, where loss of even single wetland patches could result in local species extirpation. It is unlikely that CFWs will remain in the landscape in their current state and continue to provide benefits from ecosystem services without significant management action. Even with such action, widespread loss or modification is likely and continued research is required to understand the full scope of climate change impacts.