The impacts of grazing in drylands
Professors Peter le Roux, from the Department of Plant and Soil Sciences and Thulani Makhalanyane, DSI/NRF SARChI Chair in the Department of Biochemistry, Genetics and Microbiology, led the South African component of the ground-breaking multidisciplinary study on the effects of grazing in deserts.
Although the effects of climate change have recently become the subject of extensive studies, the precise effects at global scale remain unclear.
The new study published in Science, with contributions from the University of Pretoria, reports results from the inaugural global field assessment of the ecological impacts of grazing in drylands.
The scientists found that grazing may positively affect ecosystem services, particularly in species-rich rangelands.
However, these effects turn negative under a warmer climate. “Given the large number of people relying on drylands for their livelihoods, this study provides important insights into how grazing and changing climatic conditions could alter the provisioning of ecosystem services like erosion control, carbon storage and soil fertility,” explains Prof le Roux.
Microbiomes regulates ecosystem services (The impacts of grazing in drylands)
The study includes standardised protocols to measure the impact of increasing grazing pressure on the capacity of drylands to deliver several ecosystem services.
The team measured soil erosion and fertility, forage/ wood production, climate regulation and the diversity of belowground communities such as soil fungi, protists, invertebrates and bacteria.
“We know that microbiomes are essential regulators of ecosystem services. However, due to the complexities of studying these belowground communities, we lack an understanding of the ecological impacts of grazing on their diversity and function. This work substantially advances our understanding regarding their importance as predictors of ecosystem services in different models,” says Prof Makhalanyane.
Grazing is an important land use that sustains the livelihood of billions of people – it is also tightly linked to many UN Sustainable Development Goals.
Grazing is essential in drylands, which cover about 41% of the Earth’s land surface, host one in three humans and over 50% of all livestock on Earth.
Despite the importance of grazing for humans and ecosystems, no previous study has attempted to characterise its impacts on the delivery of ecosystem services globally using field data.
This seminal study combines efforts from an international team of more than 100 researchers and provides insights and data from a uniquely global survey conducted in 326 drylands in 25 countries from six continents.
“As a team, we worked hard to coordinate sampling to include several sites from Africa. Even though a large number of Africans are directly at risk due to desertification and the effects of grazing, few global studies have included samples from these important locations,” says Prof Fernando Maestre, lead author, Distinguished Researcher at the Universidad de Alicante in Spain and director of the Dryland Ecology and Global Change Laboratory.
Response of drylands depend on local management (The impacts of grazing in drylands)
Researchers found that the relationships between climate, soil conditions, biodiversity and the ecosystem services measured varied with grazing pressure.
The results showed that carbon stocks decreased, and soil erosion increased as the climate became warmer under high grazing pressure.
This was not observed under low grazing pressure. “These results suggest that the response of drylands to ongoing climate change may depend on how we manage them locally,” says Dr Nicolas Gross from the National Research Institute for Agriculture, Food and the Environment (INRAe, France), co-author of the study.
The impacts of increasing grazing pressure shifted from mostly positive in colder drylands with a lower rainfall seasonality and higher plant species, to harmful in hotter drylands with lower plant diversity and higher rainfall seasonality.
The authors also observed that the variety of vascular plants and mammalian herbivores was positively linked to the provision of essential services such as carbon storage, which plays a key role in climate regulation.
The findings of this study are important for enhancing sustainable grazing management as well as establishing effective management and restoration actions aimed at mitigating the effects of climate change and desertification across global drylands.
This work has been carried out as part of the BIODESERT project, awarded by the European Research Council (ERC) Consolidator Grant programme to Dr Maestre.
“I am very grateful to the ERC for supporting this global survey, as such a high-risk-high-gain project would not have been possible without the generous funding and freedom that comes with an ERC grant,” says Dr Maestre.
“And of course, it would not have been possible without our network of international collaborators, who provided their expertise, resources, and work to survey sites in their respective study areas.
‘The BIODESERT survey also provides a very nice example of the power of global and collaborative research networks to conduct frontier research,” he adds.
“In addition to providing a great example of multidisciplinary research, this work is a clear demonstration of UP’s efforts to support research with societal impacts,” says UP Vice-Chancellor and Principal, Prof Tawana Kupe, who congratulated Prof le Roux and Prof Makhalanyane on their contribution to the global study.
The impacts of grazing in drylands
WhyAfrica reports about, and publishes newsletters, magazines and research reports about natural resources and the primary sectors of African economies, and the infrastructure, equipment and engineering methods needed to extract and utilise these resources in an efficient, responsible, sustainable, ethic and environmentally friendly way, so that it will benefit the people of Africa.
Furthermore, WhyAfrica promotes Africa as an investment and travel destination, analyses the continent’s business environment and investment opportunities, and reports on how the political economy of African countries affects its development.
WhyAfrica provides you with business intelligence that matters. Africa is our business, and we want it to be yours too. To subscribe to WhyAfrica’s free newsletter or digital magazine, and for more news on Africa, visit the website at www.whyafrica.co.za or send a direct message. WhyAfrica launched its first ever digital magazine in November 2021.
The company will undertake its annual road trip through South Africa, Zimbabwe, Zambia, the DRC, Malawi, Tanzania and Kenya in 2023. If you are interested in sponsorship or advertising opportunities, please contact me at firstname.lastname@example.org. We have a wide range of different packages and combo deals to give your company the greatest exposure to a rapidly growing, African readership.
The 2022 Southern Africa Road trip issue of WhyAfrica’s magazine is now available in print. The magazine was distributed in South Africa, Namibia, Zambia, Zimbabwe, and Botswana during WhyAfrica’s 2022 Southern Africa Overland Road Trip, the company’s new and innovative platform. WhyAfrica has expanded its product range and now offers its readers, followers, advertisers, subscribers and partners the following:
- Daily 24/7 online articles on WhyAfrica’s website (FREE)
- Daily updates on WhyAfrica’s social media platforms (FREE)
- Newsletters delivered to a handpicked audience every two weeks (FREE)
- Two printed magazine per year distributed at large events and during our road trips across Africa featuring original, in-depth articles (FREE) with great, on-site photographs by the WhyAfrica team (FOR SALE UPON REQUEST)
- Four digital magazines per year (FREE)
- Live updates, video clips, articles, and podcasts during and after WhyAfrica’s annual road trips (Southern Africa in 2022, East Africa in 2023 and West Africa in 2024) (FREE)
- Sponsorship and advertising opportunities for the annual WhyAfrica Overland Road Trips (PAID FOR)
- A library where companies doing business in Africa can display scientific or research papers (PAID FOR)
- A product section where companies doing business in Africa can display new offerings or services (PAID FOR)
- Media partnerships with, and a presence at, most of the major conferences and exhibitions in the African mining, energy, agriculture, infrastructure, water management, ESG, environmental management, tourism, development, and conservation sectors (FREE)
- WhyAfrica connects potential investors with new ventures in Africa and suppliers and service providers with existing companies in Africa (PAID FOR)
- WhyAfrica assists companies in generating content focused on the wider African business community (PAID FOR)
- Partnerships with companies doing business in Africa (PAID FOR)
- Partnerships with companies thinking about expanding into Africa (PAID FOR)
- In 2023 WhyAfrica members will have access to our in-depth articles about the African political economy, research, and country reports about the countries we visit on our road trips, and trends in the sectors that we cover (PAID FOR)
- A WhyAfrica book is in the pipeline and if all goes according to plan, should be published towards the end of 2023 (PAID FOR)
- The WhyAfrica consultancy arm assists and advises companies doing business in Africa through utilising our extensive global business network (PAID FOR)
Become part of the WhyAfrica community. Tell us your story. Expand your footprint across Africa and partner with us to make the most of your African experience.
The impacts of grazing in drylands