The tiny hairs found on plant roots play a pivotal role in helping reduce soil erosion, a new study has found. The research, led by the University of Bristol and published in Communications Biology, provides compelling evidence that when root hairs interact with the surrounding soil they reduce soil erosion and increase soil cohesion by binding soil particles.
Researchers from the Universities of Bristol and Exeter have revealed the crucial function the microscopic roots hairs play in binding and reinforcing soil. While the larger-scale root properties such as diameter, length and surface area have been extensively studied to understand their role in preventing soil erosion, the effect that micro-scale properties, such as root hairs, has is less well documented.
The research team looked at how wild plants Arabidopsis thaliana, which produced root hairs, compared with an almost identical Arabidopsis with the same root hair structure in reducing soil erosion.
They found that, when planted in sufficient density, plants with root hairs reduced soil loss almost completely -- while otherwise identical plants without hairs could not stem the flow of erosion.
Three methods were used to explore the soil retention benefits of root hairs. First, the samples were placed in a sterile gel, in a petri dish, and then subjected to increasing centrifugal force. The study found that the hairless seedlings were easier to remove from the gel compared to seedlings abundant with root hairs. Second, the study found that root hairs were also shown to stabilise the plant in the soil, as they increased the force needed to uproot the plant. Third, in the experimental landscapes laboratory at Exeter, root hairs reduced water erosion to almost zero.
The team is now working to distinguish between these hypotheses and identify the molecules involved.
(Source: Agriculture and Food News, ScienceDaily. www.sciencedaily.com)