The Center for International Forestry Research (CIFOR and World Agroforestry (ICRAF) joined forces in 2019, leveraging a combined 65 years’ experience in research on the role of forests and trees in solving critical global challenges.
Researchers have developed a combination of remote sensing and field observation to identify land suitable for restoration.
As the debates and commitments around restoration of degraded land grow, there is a corresponding need for well-informed policy decisions. And policies need to be backed up by spatially clear information on the potential for land restoration. This is paramount in guiding the design and implementation of restoration interventions in the context of limited resources.
Researchers from the Center for International Forest Research and World Agroforestry (CIFOR-ICRAF) have assessed ecosystem indicators of land degradation using a systematic approach that combines field surveys and remote-sensing data to map potential for restoration in the semi-arid areas of Chad.
The research team used the Land Degradation Surveillance Framework (LDSF) to conduct a systematic baseline assessment of soil and ecosystem health in eight landscapes covering 88,344 km2 across the Sahelian zone of the Republic of Chad. The area’s soils are mainly sandy, rocky and calcareous or siliceous, typically with low inherent fertility, and highly susceptible to erosion. The predominant land use is either for cropping or rearing of livestock.
‘The LDSF is designed to provide a practical and cost-effective monitoring and evaluation framework for land and ecosystem health as well as mapping of soil-health and land-degradation indicators, such as erosion prevalence,’ said Leigh Winowiecki, soil systems scientist and leader of the Soil and Land Health research group at CIFOR-ICRAF. ‘The LDSF is also designed to monitor changes over time and provide opportunities for targeting improved soil management and land restoration.’
The LDSF assesses multiple indicators, including soil organic carbon, erosion prevalence, tree density, saturated hydraulic conductivity, vegetation structure, topographic position, land management, and land-use history.
Soil sampling was done using the LDSF method, with 160 topsoil and 160 subsoil samples collected per site. All soil samples were analyzed using mid-infrared spectroscopy at CIFOR-ICRAF’s Soil–Plant Spectral Diagnostics Laboratory in Nairobi, Kenya. Ten percent of the soil samples were subjected to wet chemistry analysis to develop calibration and validation models. The soil analyses results were combined with field observation data to determine the potential for restoration.
A major challenge in evaluating the potential of land for restoration has been the lack of appropriate methods and tools that are based on indicators understandable and easy to use by many different groups. The research team illustrated a simple methodology and applied it to a case study in the Sahelian areas of Chad.
Out of the total study area, 66.94% was considered suitable for restoration with moderate effort required. However, 33% was considered to require considerable effort to be restored. The areas could be restored through growing trees, deploying soil and water conservation, farmer-managed natural regeneration, and integrated soil fertility management.
‘The results can help to spatially identify suitable multifunctional restoration and regeneration hotspots as an efficient way to prioritize restoration interventions in the context of limited resources,’ said Bertin Takoutsing, associate soil health scientist with CIFOR-ICRAF, who led the field surveys in Chad.
Taking the Sahelian areas of Chad as a case study, the research team demonstrated that ground sampling combined with remote-sensing data can establish a framework useful in classifying targeted landscapes into restoration-potential classes based on soil information, land-degradation status and environmental variables, as well as evaluating the level of effort to be deployed to achieve restoration.
Read the publication
Takoutsing B, Winowiecki LA, Bargués-Tobella A, Vågen TG. 2022. Determination of land restoration potentials in the semi-arid areas of Chad using systematic monitoring and mapping techniques. Agroforestry Systems 5 Jan.
Read more
Winowiecki LA, Vågen T-G, Kinnaird MF, O’Brien TG. 2018. Application of systematic monitoring and mapping techniques: assessing land restoration potential in semi-arid lands of Kenya. Geoderma.
Chad: championing healthy soils and ecosystems through data
Lessons from Kenya on how to restore degraded land
People, healthy soils and ecosystems in Africa
World Agroforestry (ICRAF) is a centre of scientific and development excellence that harnesses the benefits of trees for people and the environment. Knowledge produced by ICRAF enables governments, development agencies and farmers to utilize the power of trees to make farming and livelihoods more environmentally, socially and economically sustainable at multiple scales. ICRAF is one of the 15 members of the CGIAR, a global research partnership for a food-secure future. We thank all donors who support research in development through their contributions to the CGIAR Fund.