Can climate benefits be reconciled with revenues for land management? Annette Freibauer 1, Hannes Böttcher 1, Yvonne Scholz 2, Vincent Gitz 3, Philippe Ciais 4, Martina Mund 1, Thomas Wutzler 1, Ernst-Detlef Schulze 1 1 MPI-BGC Jena; 2 DLR Stuttgart; 3 CIRED - CNRS/EHESS Paris; 4 LSCE Gif-sur-Yvette

Outline What to optimize? Case study for forestry and cropland in Central Germany –C stocks –fossil C substitution –Net revenues and C prices Conclusions

What to optimize? Reference: functional unit scarcest resource = productive land: hectare Criteria –climate benefits –net revenue System boundaries –C stocks on land –C stocks in sector (including products) –holistic life cycle view: fossil C substitution energy provision energy embedded in products

Case study: Thuringia Agriculture –Plains –Rich soils Forest –Low mountain ranges –Poor soils Afforestation of cropland No deforestation

Regional constraints Forestry –No deforestation –No fertilizer –No stands with exotic trees –Subsidies for old-growth hardwood forests for non-use (FFH) Agriculture –No C loss from soils –Subsidies: area-based, independent of product extra for renewables Product use –No organic material in landfills: complete waste incineration (assumed: 80%)

Elements of study Cropland Incineration Long-lived products Short-lived products Consumption / Decay Landfill Afforestation Food Decay on site Forest Energy Timber Conservation Recycling / reuse Original land usePurpose Products

Cropland: a hectare of cereals Food only Food + straw Set-aside –Annuals –Poplar –Afforestation

Forestry: a hectare of beech or spruce Land use decisions –Continue timber production –Switch to bioenergy –Sequester carbon on-site: conservation 3 levels of productivity 3 levels of accessibility (slope)

C stocks: forest

C stocks: cropland

C stocks: Timing matters! Trade-off between fast accumulation and large accumulation

Fossil C substitution Combined heat and power plant; natural gas Heat plant; light heating oil Power plant; lignite Regional substitution effectiveness in Thuringia Winter wheat, whole crop Spruce, slash Scaling fraction t fossil-C saved per t bioenergy-C

Climate effects in forestry C stocks in soil, biomass & products C stocks + substitution Mean C benefits over 150 years (t C/ha) time Years C stocks + cumulative C substitution, tC/ha Spruce for products Spruce for energy Spruce for sequestration Spruce for products Spruce for energy Spruce for sequestration Benefits by recycling

Climate effects in cropland Mean C stocks (t C/ha) over 150 years time Years C stocks + cumulative C substitution, tC/ha Wheat for food Straw for energy Poplar for energy Oak for products Wheat for food Straw for energy Poplar for energy Oak for products First pulp, then energy

Forestry: What pays off most? without subsidies with subsidies spruce timber spruce conservation spruce energy spruce timber + conservation

Cropland: What pays off most? without subsidies with subsidies afforestation poplar food+straw afforestation

Concept of maximum climate benefits Conservation Timber forestry Bioenergy Agriculture Carbon stocks in ecosystem Productivity / accessibility Low High Land use intensity Land use priorities Black: Conservation Grey: Forestry White: Agriculture C sequestration prices C prices by substitution effectiveness

What is best? High C stocks: Conserve them High productivity: Use it effectively