Testing the potential use of UK wetland plant species in paludiculture using examples from the Somerset Levels

Abstract

The trade-off between economic benefits and environmental sustainability results in the unsustainable use of wetlands through conversion to agricultural land. As a result, causing peat degradation, reducing the ecosystem’s capacity to provide ecosystem services. Paludiculture, the concept of cultivating wetland plant species in rewetted conditions that can be converted and utilised commercially, presents an opportunity to harmonise economic stability and environmental protection. However, most research into paludiculture has been conducted in continental Europe; there is a knowledge gap regarding paludiculture in the UK. In this research, seven UK wetland plant species were harvested from the Somerset Levels, a low-lying wetland area with high agricultural presence and nutrient contamination. Samples were harvested as close to a monoculture as possible using a 0.25m2 quadrat, freeze-dried to enable the dry biomass production to be calculated, milled, and then passed through an X-ray Fluorescence (XRF) and Carbon, Hydrogen, and Nitrogen (CHN) analyser to determine the nutrient removal capacity of each plant species. Statistical analysis, including a one-way ANOVA test, identified a significant difference between the dry biomass production of the plant species; Typha latifolia produced the greatest dry biomass yield of 50.32 t ha-1-yr-1, followed by Phragmites australis; Glyceria maxima produced the smallest dry biomass yield of 3.35 t ha-1-yr-1. Furthermore, T.latifolia demonstrates a significantly greater nutrient removal capacity, potentially removing 21.8 t ha-1-yr-1 of carbon and 3.12 t ha-1-yr-1 of phosphorus per yield, followed by P.australis. These findings show that T.latifolia and P.australis have the greatest potential for paludiculture within the UK to remediate nutrient contamination and restore the wetlands whilst maintaining land productivity. Although this study has demonstrated the potential of paludiculture on the Somerset Levels and Moors (SLM) the individual conditions of alternative locations in the UK, such as soil pH and water table depth, should be revised to determine the suitability for paludiculture.