River Parrett is a 'pre-English river-name of obscure origin'. The River Parrett, the Bristol Channel and the Severn Estuary are believed to have been used for riverine bulk transportation of people and supplies in Somerset under Roman and later Anglo-Saxon and Norman occupation. Roman Somerset, which lasted for over 250 years until around the beginning of the 5th century, had various settlements, including Bath ("Aquae Sulis"), Ilchester ("Lindinis") and lead mines at Charterhouse; and four roads surrounding the Somerset Levels. There is evidence of two Roman ports on the Parrett. The port at Combwich, on the west bank, was ill-recorded before its
Aphanizomenon flos-aquae it had a profound effect on natural killer cells (NKCs). "A. flos-aquae" triggers the movement of 40% of the circulating NKCs from the blood to tissues. Some compressed tablets of powdered "A. flos-aquae" cyanobacteria (named as "blue green algae") have been sold as food supplements, notably those filtered from Upper Klamath Lake in Oregon. Aphanizomenon flos-aquae Aphanizomenon flos-aquae is a brackish and freshwater species of cyanobacteria found around the world, including the Baltic Sea and the Great Lakes. "Aphanizomenon flos-aquae" can form dense surface aggregations in freshwater (known as "cyanobacterial blooms"). These blooms occur in areas of high nutrient loading,