Limitations of growth-parameters in Lemna gibba bioassays for arsenic and uranium under variable phosphate availability.

摘要: Abstract Growth behaviour of Lemna gibba L. at different phosphorus supply, and arsenic or uranium exposure levels was investigated in batch culture. Total frond count, total area, dry biomass were used to observe growth four phosphate, arsenic, concentrations. had a linear relationship with the area ( r = 0.96 P 0.001 ), but non-linear count. Using count led significantly lower rates than did use high phosphate whereas higher under low conditions. The results loading more less mirror obtained variation, except that for experiments. At lowest loading, this not observed because toxic . longest roots highest load. No significant influences on root length loading. individual increased an increase decreased considerably uranyl arsenate multiplied rapidly into small yellowish fronds exposure. first developed size before multiplying favourable environment. effect may be attributed interaction between ions phosphates precipitate phosphates. revealed is very much influenced by multiple stresses bioassay. Therefore, rate calculation models should chosen according parameter used, toxicity estimation differs measured. Consequently, interpretation bioassay can influenced.