Effects of environmental conditions on the phosphorus distribution of constructed duckweed (Lemna minor) microcosm

The restoration of eutrophicated lakes using duckweed plants (Lemna minor) is recognised as a potentially low-cost method. In this study, the effects of environmental conditions on phosphorus (P) distribution were investigated in constructed duckweed microcosms by means of 32P isotope labelling; 32P activities in microcosms were monitored to determine P distribution activities. Results indicated that high phosphate, low ammonium concentrations, moderate pH values, and higher environmental temperatures promoted duckweed growth and favoured mobile P release from sediments. Under comfortable conditions, restoration of eutrophic lakes by means of duckweed could, to some extent, reduce internal P loads of lake sediments.