To safeguard dune wetlands and to provide sustainable management practices into the future, there is a critical need to increase our knowledge around the factors which regulate dune slack plant communities, and to design science-led interventions to protect these high conservation habitats from current and emerging threats. The primary aim of this thesis was to explore the spatial and temporal dynamics of the hydrology regime and its associated dune slack plant communities at Newborough Warren, in an effort to improve our fundamental understanding of dune ecosystem functioning and to contribute to the formulation of improved dune slack management and conservation practices. By integrating field monitoring, statistical analysis and numerical modelling, this thesis sets out to gain a better understanding of the relationship between dune slack vegetation and underlying hydrological regime. First, our study confirmed the potential of using 3D-hydrological modelling to run and evaluate scenarios of forest management which may affect groundwater levels within the dune system. The hydrological model allowed for successful predictions of management interventions, and therefore, shows how model and field monitoring can be combined to predict the impact of current and future management interventions. Secondly, this thesis highlights the role of hydrology as a driver of dune slack vegetation change. We analysed the relationships between vegetation and hydrology metrics, with the intention of their utilisation for management and conservation. The 5-year average mean spring level (MSL) was the metric which best explained and predicted overall dune slack plant community responses to hydrological regime. We conclude that vascular plant dune slack community responses can be predicted with a range of hydrology metrics and that these can provide a valuable management tool to monitor and interpret observed changes. Further, we revealed that species composition significantly moderated the relationship between hydrology and vegetation response within groups of dune slack communities. This moderating effect was evident for both vascular plant and bryophyte communities, with different multi-year metrics for bryophytes (8-year average rather than 5-year average for vascular plants), highlighting the importance of accounting for species assemblages in statistical analyses of vegetation response in dune wetlands. This finding highlights that ideally dune slack vegetation should not be treated as a homogeneous entity in terms of hydrological responses, and it enables a more refined understanding of the dune slack hydrology-vegetation linkages. And lastly, this thesis also addresses important questions regarding dune slack vegetation response and the effect of the inter-annual dynamics, as well as moderating factors such as soil organic matter content which influences the responses of dry dune slack communities to hydrological change. As a result, we now have a better understanding of the short- and medium-term dynamics behind the drivers of the hydrological relationship within and between dune slack communities. However, to fully understand the dynamics behind vegetation response on all levels, more research is needed to better understand the resilience and recovery response of dune communities to climate change for future management and dune slack conservation. To get a more complete understanding of the dynamics around tipping points on different levels, we do need to incorporate the full range of dune slack communities, in excellent- or poor-conditions, and potentially beyond the tipping points to understand the full extent of resilience. Our results also suggest that more research is needed to understand bryophyte dynamics, as they often play a vital role within dune slack communities, but are poorly understood. Therefore, the findings in this thesis conclude that long-term monitoring is necessary, especially with repeated measures, to determine the short-term and long term dynamics and how they affect vegetation response around hydrological change in the future.