Abstract

Batch-fed horizontal sub-surface flow constructed wetlands (HssFCW) were developed to compare the potential of Canna indica and Oryza sativa L. in removing heavy metals and nutrients from piggery effluent. Piggery effluent samples were characterized for nutrients (N and P) and metals (Mg, Al, Ca and Fe) before and after introducing them to the HssFCW with hydraulic retention time (HRT) of 3 days and operational flowrate of 0.014 m³/day. Three sets of constructed wetlands (CWs) were monitored during the dry season for 3 months. The bioconcentration factor (BCF) and translocation factor (TF) for the plants were evaluated. The results were all significantly different at p ≤ 0.05. O. sativa L removes more nutrients and metals than C. indica. The BCF for O. sativa L. was higher than for C. indica, while the TF for C. indica was higher for O. sativa L., indicating a higher metal translocation potential. Use of C. indica, a non-food crop, poses no health risks in HssFCWs whereas the grains of O. sativa L. are consumed directly by humans, presenting potential risks when used in HssFCWs. Compared to an annual O. sativa L., the perennial C. indica can be grown continuously in CWs for the phytoremediation of piggery effluent.

• Novelty statement

• No known work about the phytoremediation potential of the two studied macrophytes in the agro-ecological zone is known. The study also provides insight into the bioconcentration of metals in the edible part of Oryza sativa L. FARO 44 (SIPI 692033).

• The characterization of piggery effluent revealed that its compositions were above the allowable limit for reuse and recycling despite the adoption of low-water use intensive method.

• The study showed that Oryza sativa L accumulates more metals in the above-ground tissues than in its root and provide insight into its use as a phytoremediation plant in the study area.

• The footprint of pollutants and metals in Oryza sativa L makes a perennial C. indica more suitable than O. sativa L. in piggery effluent phytoremediation.

摘要

开发了分批喂料水平地下流人工湿地 (HssFCW) 以比较 Canna indica和Oryza sativa L.在去除猪舍污水中的重金属和营养物质方面的潜力。在将养猪流出物样品引入 HssFCW 之前和之后，对它们的养分（N 和 P）和金属（Mg、Al、Ca 和 Fe）进行表征，水力停留时间 (HRT) 为 3 天，操作流速为 0.014 m ³ /天. 在旱季对三组人工湿地 (CW) 进行了为期 3 个月的监测。评估了植物的生物浓缩因子（BCF）和易位因子（TF）。结果在p  ≤ 0.05 时都有显着差异。苜蓿去除比C. indica更多的营养物质和金属。O. sativa L的 BCF 。比更高美人蕉，而TF为美人蕉是对于较高O.水稻，指示较高的金属易位潜力。使用C. indica 是一种非粮食作物，对 HssFCWs 没有健康风险，而O. sativa L.的谷物直接被人类食用，在 HssFCWs 中使用时存在潜在风险。与一年生的O. sativa L.相比，多年生的C. indica可以在 CW 中连续生长，用于猪场污水的植物修复。

• 新颖性声明

• 没有已知的关于农业生态区中所研究的两种大型植物的植物修复潜力的工作。该研究还提供了对Oryza sativa L可食用部分金属生物浓度的深入了解。FARO 44 (SIPI 692033)。

• 猪场污水的表征表明，尽管采用了低用水密集型方法，但其成分仍高于再利用和回收的允许限度。

• 该研究表明，水稻在地上组织中积累的金属比在其根中积累的金属多，并提供了对其在研究区作为植物修复植物的用途的深入了解。

• Oryza sativa L中污染物和金属的足迹使多年生C. indica比O. sativa L.更适合猪场污水植物修复。