Mixed plantings of carex appressa and lomandra longifolia improve pollutant removal over a monoculture of L. longifolia in stormwater biofilters

Abstract

Stormwater biofilters process diverted runoff through dense vegetation followed by vertical filtration through a porous soil-based media. The plant community is an essential component of a biofilter, yet the evaluation of the efficacy of plants for biofiltration has predominantly been attempted only as single-plant pot experiments. This paper investigates the effects of multi-species planting on pollutant removal to reveal how the relationship between two plants frequently used in biofilters affects effluent water quality. Carex appressa and Lomandra longifolia plants were grown in laboratory scale stormwater biofilters in groups of four, with plant communities comprising a monoculture, 25:7..