Exploring the Coastal Vegetation of Oman: A Multifaceted Approach Using Ecological Surveys and Species Distribution Models to Inform Conservation

Abstract

The Sultanate of Oman harbours a diverse array of flora from multiple biogeographic zones and has received significant progress in botanical research in recent decades. Despite this, the coastal vegetation remains understudied and overlooked and faces many threats such as development, overgrazing and climate change. This thesis addresses this knowledge gap by integrating field surveys alongside species distribution modelling to inform conservation strategies.
The central coastline is a particularly understudied area and was the focus of a baseline ecological assessment. Surveying revealed a total of 94 plant taxa, including 17 national Red List species. Clustering analysis identified six floral communities with distinct floral compositions. Generalised linear mixed models showed that species richness was influenced by several variables including habitat type. Species richness was notably high around Masirah Island as well as sites featuring coastal escarpments which supported a higher proportion of endemic species.
The focus shifts to a larger scale using species distribution models to maximise the limited data available. Neltuma juliflora, a highly problematic invasive species on Oman’s coast, was modelled using an ensemble species distribution model, revealing several areas of high habitat suitability along the coast. Future climate scenarios predict a general decline in habitat suitability, although high suitability persists around anthropogenic coastal habitats such as the Al Batinah coastal plain. The species also poses a disproportionate threat to key botanical zones when compared to the rest of the country.
Modelling was also used to predict the distribution of several endemic plant species across the central desert coastal area, which is a local centre of plant endemism. The models were stacked to reveal several areas of high endemic richness. Evidence suggested that the Kuria Muria Bay Area serves as a climate refugium with stable climatic conditions and low climate change velocity which has supported the persistence of endemic flora. Future predictions indicate that this area may continue to offer refuge amid environmental changes.
This research enhances our understanding of the coastal vegetation of Oman and highlights the value of integrating field data with modelling to guide conservation efforts. Management is required to protect Oman’s coastal vegetation by increasing the coastal protected area network, preventing the spread of N. juliflora and protecting endemic-rich areas from development and overgrazing.