The global population is projected to exceed 11 billion by 2100. Such an increase in human population would imply an increment in the demand of meat and dairy, resulting in a larger portion of land surface dedicated to grazing for livestock –over 25% of emerged lands is already dedicated to this. Pasturing is one of the most common methods for raising livestock, and play a critical role in maintaining food production, which is of special importance to developing countries. However, grazing by livestock can also result in multiple negative impacts for biodiversity and ecosystem functioning, resulting in desertification processes. Because of this, “one of the most important challenges we face over the next few decades is to maintain a sustainable production of food for the billions of new inhabitants on Earth, while protecting the health of our ecosystems” explains Dr. Manuel Delgado Baquerizo from the University Rey Juan Carlos (URJC) and co-author of this work.
The study, published today in the prestigious journal PNAS, suggests that increasing the diversity of herbivores in the field –within comparable levels of grazing intensity– can help promote the biodiversity and ecosystem functioning of grazed ecosystems. More specifically, this study indicates that by increasing the biodiversity of livestock in the field (e.g., cattle along with sheep vs. cattle or sheep exclusively), we can enhance the biodiversity of plants and insects under grazing conditions, indirectly promoting the levels of functioning for multiple ecosystem services including nutrient cycling, plant production, and storing carbon in soil , which otherwise would be in the atmosphere, among many others. The positive link between herbivore, plant and insect biodiversity, also indirectly promotes the associations between the biodiversity of soil organisms and ecosystem functions. “Learning how to manage our resources in the field is of paramount importance to maximize both the production of food, and the sustainability of our ecosystems” indicates Dr. Ling Wang from the Northeast Normal University at China.
To achieve these results, the researcher conducted a five year field experiment in one of the most grazed and largest remaining grassland on Earth, located in northeastern China, where, using sequencing techniques, they evaluated the impacts of livestock grazing by single species (cattle or sheep) and mixed species (sheep and cattle) on biodiversity and ecosystem functions. “Our results are essential for improving the management of pasture areas in an overpopulated world” says Dr. Delgado Baquerizo.
Manuel Delgado-Baquerizo, M.firstname.lastname@example.org