Abstract

The present study was conducted to investigate the potential of the free-floating macrophytes Pistia stratiotes to remediate nutrients and restore the eutrophic drain (Al-Sero Drain), South Nile Delta, Egypt. Plant and water samples were collected monthly for ten months using three randomly distributed quadrats in each of three sites. Monthly significant variation in all investigated water nutrients was recorded. The plant biomass showed bell-shaped distribution, with the lowest shoot and root biomass during May, while their peaks were during September. The plant shoots accumulated higher concentrations of most nutrient elements, except Mg, than the roots. The order of nutrients concentration (%) in P. stratiotes shoot was K > N > Ca > Na > Mg > P, while in the root was K > N > Na > Ca > Mg > P. Most nutrients standing stock (g/m⁻²) had the same biomass trend with the minimum during May and the maximum during August–October, which is the potential period for mowing the plant to remediate the highest nutrients and restore the eutrophic watercourses. Most investigated nutrients (except Ca) content in water were significantly correlated to their concentration in the different plant organs, which in turn provide a quantitative assessment of the environmental quality that suggests the potential use of this plant as a biomonitor of nutrient elements in eutrophic watercourses.

摘要

本研究旨在调查自由漂浮的大型植物Pistia stratiotes修复营养物质和恢复埃及南尼罗河三角洲富营养化排水沟（Al-Sero 排水沟）的潜力。在三个地点的每个地点使用三个随机分布的样方，每月收集植物和水样，持续十个月。记录了所有调查的水养分的每月显着变化。植物生物量呈钟形分布，5月份地上部和根系生物量最低，9月份达到高峰。除了镁，植物的芽比根积累了更高浓度的大多数营养元素。P. 层状藻中养分浓度（%）的顺序地上部是 K > N > Ca > Na > Mg > P，而在根部是 K > N > Na > Ca > Mg > P。大多数养分存量 (g/m ^-2 ) 具有相同的生物量趋势，最小5 月和 8 月至 10 月的最大值，这是修剪植物以修复最高养分和恢复富营养化水道的潜在时期。大多数研究的水中养分（Ca 除外）含量与其在不同植物器官中的浓度显着相关，这反过来提供了环境质量的定量评估，表明该植物作为富营养化水道中营养元素的生物监测器的潜在用途.