A phyto-guide to species selection for optimized South African green infrastructure

• Published in: Water S. A. 2021-10, Vol.47 (4), p.515-522
• Main Authors: Jacklin, DM, Brink, IC, Jacobs, SM
• Format: Article
• Language: English
• Subjects: Additives; Anthropogenic factors; Biodiversity; Bioremediation; Civil engineers; Climate change; Collaboration; Criteria; Decision making; Degeneration; Design; Ecological effects; ecological engineering; Ecologists; Ecology; Ecosystem dynamics; Ecosystems; Efficiency; Endemism; Engineering; Engineers; Environmental engineering; Environmental impact; Flowers & plants; Green infrastructure; Human influences; Hydrology; Infrastructure; Infrastructure (Economics); Invasive plants; Invasive species; Knowledge; Mitigation; Morphology; Physiology; Phytoremediation; phytotechnologies; Plant introductions; Plant species; Pollutant removal; Pollutants; Pollution; Practical guide; Rehabilitation; Removal; Sediment pollution; Soil degradation; Soil pollution; Soil water; Stormwater management; Success; Sustainability; Sustainable development; System effectiveness; Urban planning; Wastewater treatment; Water pollution
• ISSN: 0378-4738; 1816-7950
• DOI: 10.17159/wsa/2021.v47.i4.3875

In South Africa, rapid environmental degeneration caused by anthropogenic pollution poses a major ecological engineering problem, demanding proper resource mitigation strategies. For the treatment of polluted water and degraded soil systems, green infrastructure (GI) ofers an efective, sustainable and afordable nature-based alternative to grey infrastructure. An additive benefit within GI, plant species provide enormous potential to treatment; however, species vary substantially in their pollutant removal and hydrologic performance. South African civil engineers tasked with designing GI often lack expertise and knowledge of plant behaviour and ecosystem dynamics. Therefore, this paper proposes a decision framework to facilitate selection for designing local GI in the form of a phyto-guide, based on existing recommendations and knowledge of removal processes and plant behaviour. Interdisciplinarity at the core of the phyto-guide relies on continuous specialist collaboration with each selection criteria, whilst eficiency and sustainability are considered equally important contributors to successful GI functioning. The spread of invasive alien plants, whether accidental or deliberate, negatively impacts an ecosystem's capacity to deliver goods and services. Thus, the desire to optimize GI by incorporating efective phytoremediators cannot be prioritised over conservation concerns. In addition, this paper seeks to advance the GI limitation of relying solely on previously identified phytoremediators, by including evaluation criteria of beneficial plant traits as well as plant distribution, behaviour and diversity into the decision-making process for optimized GI. It is recommended that future research engages in discovering less invasive, naturally occurring local species as potential phytoremediators, inspired by South Africa's rich biodiversity and endemism, as well as conveying the importance of consultation with engineers and ecologists for optimized GI.