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Highlights • Anaerobic digestion is an effective treatment for excessive growth of macrophytes. • Microalgae effectively removed inorganic nutrients from the ADEs. • Appropriate dilution (e.g., 10-fold) of ADEs was needed for algal growth. • Available Mg in the ADEs was not sufficient for maximum algal growth and cell yield. • Mg-enrichment of ADEs was essential for enhancing algal growth and nutrient removal. Abstract Green microalgae have great potential for removing inorganic nutrients from wastewater and anaerobic digestion effluent (ADE). We investigated the cultivation conditions for maximum algal yield and nutrient (ammonium and phosphate) removal rates. The green microalga, Chlorella sorokiniana, was cultured using ADE from anaerobic digestion by two dominant macrophytes, Elodea nuttallii and Egeria densa , which cause environmental problems in Lake Biwa, Japan, because of excessive growth. Available magnesium (Mg) in the ADEs from both macrophytes was not sufficient for maximum algal growth and nutrient removal. We demonstrated that Mg-enrichment was essential for enhancing algal yield in, and nutrient removal rate from, ADEs. [ABSTRACT FROM AUTHOR]

Abstract: We investigated the vertical structure of physicochemical properties in 27 lakes at Skarvsnes and Langhovde, Syowa Oasis, East Antarctica, from December 2003 to February 2004. The lakes were classified into three types based on their origin and geographical characteristics: non-marine relic lakes, marine relic and lotic lakes, and marine relic and lentic lakes. We describe the physicochemical characteristics of each lake type. When the non-marine relic lakes were partly covered with ice, the water column was stratified beneath the ice. In the non-marine relic lakes, during the season with no ice cover, physicochemical parameters were uniform throughout the water column, probably due to frequent vertical mixing induced by wind force and thermal convection within the shallow basins. Similarly, in marine relic and lotic lakes, lake waters appeared to be completely mixed because of a large inflow of meltwater from glaciers and outflow to other lakes and the coastal sea. In the marine relic and lentic lakes, except for Lake Himebati-ike, the lake water was vertically stratified with a strong halocline. In Lakes Suribati-ike and Hunazoko-ike, salinity was very high (up to 20%) due to evapoconcentration. Lake Suribati-ike is a meromictic lake, with a monimolimnion developed below 10m water depth. [Copyright &y& Elsevier]