室内利用MA培养液进行藻类增长潜力(AGP)试验,考察了不同有机配体(EDTA、NTA和DTPA)与Fe^3+形成的配合物对铜绿微囊藻生长的影响。结果表明,Fe-EDTA、Fe-NTA和Fe-DTPA均能显著促进铜绿微囊藻的生长,提高Fe的生物可利用性,但三者之间没有表现出明显差异;Fe-NTA能显著提高叶绿素a含量,Fe-EDTA和Fe-DTPA对提高叶绿素a含量不明显,3种有机配合态Fe对铜绿微囊藻叶绿素a含量影响大小为Fe-NTA〉Fe-DTPA、Fe-EDTA;Fe的有机配合态比羟基配合态更有利于促进铜绿微囊藻的生长和吸收利用。
The effects of different complexes formed by Fe^3+ and organic ligands (EDTA, NTA and DTPA) in MA medium on growth of Microcystis aeruginosa were studied in laboratory. Use MINTEQ procedure, calculate the concentrations of EDTA, NTA and DTPA which made all of Fe^3+ complexed in each solution, add the proper concentrations of three organic ligands in test solutions respectively, inoculate Microcystis aeruginosa and experimentize algal growth potential (AGP) test. We mensurated the daily biomass of Microcystis aeruginosa, the content of Microcystis aeruginosa's Chl-a and the distribution of iron at the end of cultivation in each group. The results showed that: compared with the control group, all of three organic complexes of iron promoted the growth of Microcystis aeruginosa and enhanced the bioavailability of iron obviously, but there was no obvious difference among these groups; Fe-NTA enhanced the content of Microcystis aeruginosa' s Chl-a obviously at the end of cultivation, synchronously Fe-EDTA and Fe-DTPA did not. The effect extent of three organic complexes of iron on the content ofMicrocystis aeruginosa' s Chl-a at the end of cuhivation was: Fe-NTA 〉 Fe-DTPA, Fe-EDTA; On promoting the growth of Microcystis aeruginosa and enhancing the bioavailability of iron, organic complex forms of iron were more effective than hydroxy complex form.