Assessment of seagrass health in response to water quality in the Solent

Tender description

Background to Project Concerns around water quality (elevated nutrients) in our estuaries is currently leading to agencies to seek for improvements to agriculture, wastewater treatment works and nutrient neutrality in development. Environment Agency data for Dissolved Inorganic Nitrogen, phytoplankton and opportunistic macroalgae covering littoral sediment, is currently used a proxy indicator to assess the water quality-nutrients attribute for intertidal and subtidal seagrass. Evidence is currently largely based on the impacts on mudflats from opportunistic macroalgae. However, there is concern that this current indicator of water quality is not taking account sufficiently the wider ecosystem effects of elevated nutrients in our estuaries. Water quality sampling can vary greatly throughout the year, assessments of these using these indicators are not always close to where the Zostera beds are present and there is literature that suggests seagrass health can be affected at lower nutrient concentrations than indicated by high densities of macroalgae over littoral sediment.