Understanding the Role of Vegetation in Biofiltration Systems
(2010 – current)
While there are many water sensitive technologies available to manage stormwater flows from urban areas, biofiltration systems (also known as biofilters) show the greatest potential to urban designers due to their relatively low cost and retro-fitting possibilities. By taking advantage of natural processes such as evapotranspiration, filtration and adsorption, biofilters can reduce the impact of urban stormwater on receiving waterways. However, the nutrient removal capacity of biofilters is highly dependent on the vegetation used. Unfortunately, very few studies are available to optimise the selection of plants for biofilters, leaving designers with a lack of guidance.
The aim of this project, funded by ARC Linkage (in conjunction with Melbourne Water and the WA Dept. of Water) is to better understand the nature of nitrogen removal processes in biofiltration systems, and the role of vegetation in those processes, so that biofilters can be designed to have greater and more reliable nitrogen removal. This project has two distinct objectives:
- Identify the influence of plant morphological traits on nitrogen removal by biofiltration systems, and in doing so, to provide a basis for plant selection in both south-eastern and south-western Australia.
- Identify and quantify the nitrogen transformation processes occurring in biofilters, and relate these processes to (i) plant morphological characteristics, (ii) biofilter design and (iii) climatic conditions, so as to provide a basis for future design manipulations to increase nitrogen removal by biofilters.
This project supports two postgraduate research projects. The first examines the role of plants in determining the treatment performance and the evolution of hydraulic conductivity, being undertaken by Tracey Pham (The Influence of Vegetation on Hydrology and Nutrient Removal in Biofilters). The second, undertaken by Emily Payne, is investigating the nutrient transformation processes occurring within the biofilters, using isotope tracers to determine the location and fate of nutrients within the system (The Influence of Plant Species on Nitrogen Removal within Biofilters).
Associated Postgraduate Projects:
- The Influence of Plant Species on Nitrogen Removal within Biofilters (PhD) – Emily Payne
- The Influence of Vegetation on Hydrology and Nutrient Removal in Biofilters (Masters) – Tracey Pham