Can forest floor mirrors boost plant growth?

A mirror system increases light exposure to improve seedling survival rates

Spotted: Around 45 per cent of the world’s flowering plant species are now threatened with extinction, and conservationists are in a race against time to protect our planet’s biodiversity. Often, though, there are critical knowledge gaps that hinder the progress of conservation projects. Now, researchers in Guam have highlighted one solution.

The legume tree, Serianthes nelsonii, is restricted to the Mariana Islands of Rota and Guam and is considered one of the most endangered native plant species in the world. The Plant Physiology Laboratory at the University of Guam carried out a study that identified key vulnerabilities of the endangered tree. These included the minimal amount of sunlight that penetrates the sub-canopy in Guam’s densely packed karst forest. The team experimented with positioning reflective materials around the tree seedlings to increase available light.

The study showed that seedlings with mirror systems installed beneath them had an increased survival rate of up to 160 per cent. The conservation technique also improved plant growth by more than 170 per cent, increased their stem diameter by 60 per cent, and boosted the number of leaves they grew compared to the plants without mirrors.

Historically, black plastic mulching with reflective properties has been pioneered in some horticulture and farming production systems to increase light to crops on a larger scale. This newly developed conservation technique, however, is specifically designed for smaller-scale regeneration projects and involves minimal costs.

Written By: Jessica Wallis