Towards Resilient Futures: Can fibre-rich plants serve the joint role of remediation of degraded mine land and fuelling of a multi-product value chain?

In this first working paper, we investigate the ability of fibre crops to grow on mine land which is typically degraded to assist in the rehabilitation of this degraded land, whilst providing a range of raw materials, including fibre crops, for valorisation. This includes transformation of these fibre-based feedstocks into fibre-derived products as economic outputs. Soil and climate data from mining areas in South Africa were compiled and used to identify fibre crops for cultivation. The following crops were selected, based primarily on their temperature tolerance and rainfall requirement: Bambusa balcooa, flax, hemp, kenaf and sisal. While these crops can demonstrate the dual ability of remediating land and producing fibre, the efficacy of this dual system is challenged depending on the level of contamination of the degraded land. Fibre crops can usually tolerate low to moderately polluted soil, but a high level of pollution is detrimental to their growth, with the added risk of metal accumulation in the fibrous biomass, thus increasing the complexity of the processing of these raw materials into products of choice owing to the need to ensure product safety depending on the target markets. To maximise the crops’ growth and fibre production on heavily contaminated land, it is recommended that the land is first restored by physico-chemical or biological means to provide a conducive environment for the fibre crops. It is further recommended that this feasibility study be extended to conduct field experiments on selected sites to further assess the potential and practicality of the proposed approach, while developing a refined inventory of its outputs and challenges.