“Turning Waste Wool into a Circular Resource: A Review of Eco-Innovative Applications in Agriculture”

from Agronomy - “an international, peer-reviewed, open access journal on agronomy and agroecology published semimonthly online by MDPI” - published February 2025

Article excerpt - “…To limit the linear economic ‘take–make–use–dispose’ model [37], which is functional to increase profits by consuming primary resources and increasing demand for short-cycle products, sheep wool should be considered as a wasted resource [38].

Sheep wool fibers are composed of some essential nutrients such as carbon (C, 50%), nitrogen (N, 16–17%), and sulphur (S, 3–4%). These elements, along with various micronutrients like copper (Cu), manganese (Mn), iron (Fe), and zinc (Zn), are essential for plant nutrition [39]. In addition, wool fibers have good water absorbing and retention properties [40,41] and can reduce pH in highly alkaline soils [42]. Also, the slow release of nitrogen into the soil, due to the complex wool keratin structure [43], compared to the rapid release from mineral fertilizers that causes nitrate leachates [28], reduces water contamination, allowing soil fertility to be maintained over time, thus reducing the use of synthetic fertilizers [44,45]. These characteristics meet the need of the livestock systems to minimize GHG emissions [46], to increase soil C stocks, and to improve N use efficiency through more sustainable farming practices. The exploitation of keratinous wastes could contribute to tackling the high volume of biomass that can be harmful to the environment, instead providing resources, feedstock, and raw materials to produce keratin-based by-products for value-added applications [47].

The biomass produced from agroecosystems is the basis of our food system and future bioeconomy [48]. Sheep wool can be a protagonist of circular bioeconomy strategies that can be at the heart of agroecosystems. Agriculture and the environment are closely linked, so the use of sheep-wool-based materials, derived from livestock activities, can have a positive impact on agroecosystems and rural landscapes…”

For more, read on at https://www.mdpi.com/2073-4395/15/2/446