This document discusses maintaining and improving soil health in Africa. It notes that investments in soil fertility and infrastructure can reduce poverty by decreasing yield gaps. Soil is a key natural resource that provides multiple ecosystem services. The objectives of Land Degradation Neutrality include maintaining ecosystem services and productivity while increasing resilience. Soil organic carbon is important but difficult to measure and monitor. New techniques like soil spectroscopy can help with analysis. Systematic field assessments can provide data on land and soil health for mapping and monitoring changes over time. Maintaining healthy soil supports healthy crops, livestock, and people.
Healthy living soils sustaining increased productivity and ecosystem services
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Ermias Betemariam
Leigh Winowiecki
Tor-Gunnar Vagen
Healthy living soils: sustaining increased
productivity and ecosystem services
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“Yield gaps as poverty traps”
Tittonell and Giller (2013)
Investments in roads and improvements
in soil fertility potentially reduce
poverty rates
(Okwi et al.,2013)
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Soil as key natural capital for multiple ecosystem services
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The objectives of LDN are to:
• maintain or improve the sustainable delivery of ecosystem services;
• maintain or improve productivity, in order to enhance food security;
• increase resilience of the land and populations dependent on the
land;
• seek synergies with other social, economic and environmental
objectives; and
• reinforce responsible and inclusive governance of land
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Shifting cultivation as forest loss in Africa
Classifying drivers of global forest loss (Curtis et al. 2018)
Counterbalancing future land degradation
• More attention to address past land degradation
• But we rarely anticipate (forecast, model, project) likely NEW degradation
• Monitoring progress & learning for adaptive management (Research)
• Information for informed public &private decisions to optimize the
selection of interventions & minimize trade offs.
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Tillage: increases respiration: SOC decrease
Harvesting: reduces inputs = SOC decrease
Land use change = SOC increase or decrease
SOC sequestration = Increasing SOC stocks through the increase of inputs
and/or decreasing C decomposition (M. Stocking, 2012)
Inputs
Litter, roots, branches,
microbes
Outputs
• Autotrophic respiration: roots
• Heterotrophic respiration: CO2 respiration of soil
organisms that use dead plant matter as a food
source
What determines the amount of SOC?
SOC: you lose it fast you regain it (very) slowly
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• Measuring & monitoring SOC is challenging
• Express the uncertainty in recommendations or to validate them
• Avoid transfers decision risk to users
• Using SLM practices as a rewarding mechanism,
behavioral change
Evidence: effects of SLM on SOC
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Ermias Betemariam | COP13| Ordos, China| Sept. 14, 2017 |
Evidence: effects of SLM on the environment
Holistic valuation of SLM impacts on ecosystem services is important
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Soil spectroscopy
§ Rapid
§ Low cost
§ Reproducible
§ Predicts many soil
functional properties
New advances in soil health monitoring
Capacity development is a priority in Africa
(15 countries have soil spectral labs)
• Africa Soil Information Service (AfSIS)
• EthioSIS, GhaSIS, NiSIS, TanSIS
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• The Land Degradation Surveillance
Framework (LDSF)
• A systematic field-based assessment
of multiple variables at the same
geo-referenced location
• Allows for rapid assessments of indicators
of land and soil health
• Allows for the production of high quality
maps of key indicators
• Robust statistical analysis on drivers of
degradation
• Can be used to monitor changes over
time
• Field guide available online here:
http://landscapeportal.org/blog/2015/03
/25/the-land-degradation-surveillance-
framework-ldsf/
Using Systematic Biophysical Assessments of Land and Soil
Health: Establishing Baselines and Monitoring Trends
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http://landscapeportal.org/blog/2015/03/25/the-
land-degradation-surveillance-framework-ldsf/
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National Soil Organic Carbon Stock Estimates
Winowiecki, L., Vågen, T.-G., & Huising, J. (2014). Effects of land cover on
ecosystem services in Tanzania: A spatial assessment of soil organic carbon.
Geoderma, 263. https://doi.org/10.1016/j.geoderma.2015.03.010
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• gdg
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https://theconversation.com/lessons-from-kenya-on-
how-to-restore-degraded-land-98178
Relationship between low carbon in the soil and high erosion – to
prioritize and monitor land restoration options
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Maps of Soil Organic Carbon- Decision Dashboards
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http://landscapeportal.org/tools
http://www.worldagroforestry.org/shared
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Healthy soils Healthy crops Healthy livestock Healthy people
Thank you
Ermias Betemariam (e.betemariam@cgiar.org)
Leigh Winowiecki (L.A.WINOWIECKI@CGIAR.ORG)
Tor-Gunnar Vagen (T.VAGEN@CGIAR.ORG)