The Release of Phosphorus from Pond Sediments and Its Availability to Lemna Minor L.

摘要

Results are reported of a study of the availability of phosphorus released from pond sediments under aerobic and anaerobic conditions to Lemna minor L. A bioassay technique using Lemna to measure available phosphorus was developed and the results compared to chemical assays. A preliminary study showed that frond numbers,root length, frond diameter,and dry weight consistently reflected phosphorus concentrations in solution. Greater release of available phosphorus took place under anaerobic conditions than under aerobic conditions. Extractable phosphorus values of the sediments correlated well with bioassay growth responses. These findings illustrate the superiority of the bioassay over chemical methods in the estimation of phosphorus availability to aquatic plants and the greater release of phosphorus from sediments under anaerobic conditions.