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Theme 3:Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost and black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Theme 3:Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost and black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Contrasted soils and ecosystems
Within category heterogeneity: natural vs managed
Theme 3:Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-1: Where are the priority areas for soil conservation to prevent SOC losses ?
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-1: Where are the priority areas for soil conservation to prevent SOC losses ?
• Peatland : Natural peatland and intensively managed (drained) peatland
• Permafrost :management
• Humid tropic soils ?
peatlanddrylands
Vulnerability : soil properties / context
Climate change mitigation Food security
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-2: What are the realistically achievable SOC stock changes and rates of change for specific soils and land uses?
• Minimize SOC losses !• rates of losses vs. rates of gain• Much more realistic to maintain than to increase
• Achievable stocks & rates of change: values = an assessment question
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-3: What is the degradation threshold where soil restoration and SOC sequestration is no longer considered feasible?
• No degradation threshold : inappropriate concept ? Different from other types of soil degradation (erosion, salinity)
• Threshold for effectiveness of specific restoration measures (e.g. non responsive soils)
• Socio-Economic thresholds
• Importance of rates of change (available data)
• All degraded soils can be restored (technically), but :- Costs limits- The SOC stock can be restored but recovered ecosystem ≠ pristine one
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-4: What are the potential derived ecosystem services and co-benefits of SOC sequestration that would contribute to climate change adaptation and reducing land degradation?
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-4: What are the potential derived ecosystem services and co-benefits of SOC sequestration that would contribute to climate change adaptation and reducing land degradation?
• There are organic matter benefits without SOC sequestration• More organic matter is not always the better (peatland vs. mineral soils)
• Time scale: short-term benefits hard to identify• Consider larger spatial scales than the plot scale
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-5: What are the proven best management practices that prevent SOC losses and foster SOC sequestration?
• Peatland: water table regulation• Erosion control • Organic matter additions to soil
o Biomass return = f(availability of the ressource) Limits water, nutrients - sustainable intensification Trade-offs (fuel- fodder)
o Management of organic wastes
Practices known by farmers but economic limits
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-5: What are the proven best management practices that prevent SOC losses and foster SOC sequestration?
• Voluntary Guidelines for Sustainable Soil Management• Are available• Need to be defined & implemented at a national/local level
(climate soil type , cropping system, farm typology…)
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Q3-6: What are the associated policy requirements/incentives to regulate their sustainable management?
• Necessary ! Need to compensate for economic losses
• Different type of incentives when preserving natural ecosystems or managed land• Low cost incentives exist• Incentives needed for biomass utilization• Cash incentives not always feasible
• Time scale mismatch
• Need to find benefits of SSM at a short time scale• Incentives to fill the gap
Action needed in the short term
Benefits in the long term
Theme 3: Managing SOC in:3.1 Soils with high SOC –
peatlands, permafrost & black soils
3.2 Grasslands and livestock production systems
3.3 Dryland soils
Other key points
• Definition and boundaries of the system (e.g peatland)• SOM should not be reduced to C, also think about P, N
• SOC as an indicator ? YES• meaningful, responsible, visible, measurable