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The OSPAR Eutrophication Strategy requires assessment of eutrophication to be based on the ecological consequences of nutrient enrichment and not just on nutrient enrichment alone, i.e. finding reliable evidence for accelerated growth of algae and higher forms of plant life caused by anthropogenic nutrient enrichment, leading to undesirable disturbance. Fully flushed marine waters of England and Wales (salinity >30) were assessed against OSPAR's harmonised criteria of nutrient concentration and ratios, chlorophyll concentrations, phytoplankton indicator species, macrophytes, dissolved oxygen (DO) levels, incidence of fish kills and changes in the zoobenthos, using region specific thresholds. None of the thirteen assessment areas, including six nutrient enriched areas, exhibited evidence for undesirable disturbance. This paper details the methods and the overall outcome of the assessment. It presents evidence that undesirable disturbance caused by nutrient enrichment was not detected in English and Welsh marine waters assessed under the OSPAR procedure. The main reasons for the lack of eutrophication problems, such as the underwater light climate limiting the accelerated growth of algae, which might otherwise result from nutrient enrichment, are discussed. [ABSTRACT FROM AUTHOR]

The article discusses a methodology developed to evaluate the impact of human activities that constitute the direct pressures of smothering, abrasion, obstruction or sealing, and extraction on the seabed community of England and Wales. Measures initiated to test the method included mapping the spatial extent of individual and cumulative activities for 2007 by habitat type, quantifying the activities' intensities, and using published recovery times to estimate impact. Spatial footprints of benthic fishing, otter trawling in sand, and co-occurring aggregate extraction and dredge material disposal are addressed. It is argued that management efforts should concentrate on spatially extensive activities such as benthic fishing.

The article presents a study which assesses the impact of several pressures on seabed habitats in Great Britain and its recovery from the water pressures of benthic fishing and aggregate extraction. The study considered the marine waters of England and Wales as study areas and made use of vessel monitoring system (VMS) data to measure the distribution and concentration of benthic fishing in the study areas. The study fitted the dredgers which operate in England and Wales to examine the impacts of aggregate extraction and fishing pressures. Results indicate that 80% of the bottom-fished region was predicted to completely recover prior the repeat trawling. Results also show that impacts of pressures were estimated under four settings including additive, antagonistic, and synergistic impacts.