浮萍多样性对富营养化水体净化效果的影响

【目的】通过研究浮萍物种多样性对净化富营养化水体效果及其对浮萍生物质积累的影响,为未来利用浮萍混养组合修复富营养化水体及开发浮萍生物质提供理论依据。【方法】分别将青萍(Lemna aequinoctialis LC33)、少根紫萍(Landoltia punctata LC06)和多根紫萍(Spirodela polyrhiza LC15)进行单独和混合培养,测量其对富营养化水体中氮、磷的去除率,同时分析混养组合的生物质含量。【结果】由少根紫萍和多根紫萍构成的混养组合对水体中硝氮(NO3--N)、总氮(TN)和总磷(TP)的去除率最高,分别为97.05%、95.00%和97.64%;由3种浮萍构成的混养组合对水体中氨氮(NH4+-N)的去除率最高,达98.17%。由青萍和少根紫萍构成的混养组合及由少根紫萍和多根紫萍构成的混养组合具有更高的生物量增长率,由青萍和少根紫萍构成的混养组合可积累更多的淀粉,由少根紫萍和多根紫萍构成的混养组合可积累更多的粗蛋白。【结论】适当的浮萍混养搭配不仅可提高富营养化水体净化效果,还能促进生物质的积累。

Effects of duckweed diversity on purifying eutrophic water

Objective]In order to provide theoretical basis for eutrophic water purification and duckweed biomass uti-lization in the future, the effects of duckweed species diversity on eutrophic water purification and duckweed biomass accu-mulation were investigated. Method]Three duckweed species, Lemna aequinoctialis LC33, Landoltia punctata LC06 and Spirodela polyrhiza LC15, were cultured both individually and in mixture to measure their removal rates of nitrogen and phosphorus, and to analyze biomass content of mixed combinations. Result]Combination of L. punctata LC06 and S. polyrhiza LC15 showed the highest removal efficiency of nitrate nitrogen(NO3--N), total nitrogen(TN) and total phosphorus (TP), reaching 97.05%、95.00%and 97.64%respectively;while combination of L. aequinoctialis LC33, L. punctata LC06 and S. polyrhiza LC15 showed the highest removal efficiency of ammonia nitrogen(NH4+-N), reaching 98.17%. Moreover, compared with other groups, polyculture of L. aequinoctialis LC33 and L. punctata LC06, polyculture of L. punctata LC06 and S. polyrhiza LC15 exhibited higher biomass growth rate; polyculture of L. aequinoctialis LC33 and L. punctata LC06 accumulated more starch; polyculture of L. punctata LC06 and S. polyrhiza LC15 accumulated more crude protein. Con-clusion]Appropriate combination of duckweed species can enhance purifying effects of eutrophic water, and promote biomass accumulation.