Investigating the Importance of UK Seagrass Habitats and Current Conservation Action

Since 1936, at least 44% of UK seagrass has been lost and the deterioration of seagrass habitats is predicted to continue. Seagrass habitats are rich in species diversity and have the ability to sequester large quantities of carbon. Initially, a systematic review investigated threats to UK seagrass habitats, current policies, and conservation measures in place that cover UK seagrass habitat. Results from this review indicate that most reported threat in the primary literature to seagrass within the UK is eutrophication. However, current policies within the UK focus on physical disturbances to seagrass, highlighting a failure to address the most commonly reported threats to seagrass. Protecting seagrass habitats maximises the abundance of commercial fish and bivalve species within the area supporting local fisheries. Lebensspuren present within the area were measured to determine diversity within the area. Lebensspuren refers to life trails left by a species such as a shell or worm casts. A total of 300 photo quadrats were taken across three sites across the UK: Exmouth, Anglesey, and Grimsby. Results stated that there was a significant positive correlation between Z. noltii density and lebensspuren abundance and biodiversity within the area. This emphasises the importance of seagrass habitats as a habitat for numerous species along the UK coastline and emphasises the need to protect seagrass habitats from degradation to maximise density. Seagrass habitats account for 10% of marine carbon sequestration globally allowing to removal of atmospheric carbon dioxide, and hence reducing greenhouse gas concentrations. Literature searches returned three studies investigating organic carbon levels within UK seagrass sediments. Each of the studies reported a positive relationship between seagrass density and abundance and organic carbon levels. However, there was a great variability in organic carbon levels reported at each site. While denser seagrass patches lead to increased carbon burial, further research is needed to determine a more accurate picture of organic carbon levels within UK sediments. The addition of appropriate protective policies designed to offset frequent threats to seagrass such as eutrophication will lead to a higher abundance and biodiversity of species along the UK coastline as well as leading to the increased burial of carbon, offsetting UK carbon emissions