Systemic interdependencies between food, cropland yields and livestock efficiencies

Transcription

1 Systemic interdependencies between food, cropland yields and livestock efficiencies An integrated analysis for the year 2050 Christian Lauk Institute of Social Ecology, Vienna together with Karl-Heinz Erb, Helmut Haberl, Thomas Kastner, Fridolin Krausmann, Andreas Mayer, Christoph Plutzar Presentation the Workshop/Hearing Feeding the planet sustainably: from foresight to better integrated policies, November 2012, Brussels

2 Background and aim of this study Strong increases of biomass demand in the future due to a) population growth, b) richer diets and c) the increased use of bioenergy and biomaterials. Foresight studies assume that this increased demand can be met mainly by further increasing yields (i.e. biomass production per unit of land). In most foresight studies, there is thus little scope to look at the interdependence of different trajectories of demand and supply factors such as diets and yields. Which scenarios (i.e. combinations of yields, diets ) are possible, if we consider in a first step no socioeconomic but only biophysical constraints?

3 Starting point: Global biomass flows and land use in 2000 Smith et al., submitted, based on Krausmann et al., 2008, Wirsenius 2000, 2003, Haberl et al., 2007, Sims et al., 2007, Kummu et al., 2012, Faostat (online)

4 Explore the scale and option space: Modelling Philosophy Share of meat (4) Type of meat (3) Livestock diets (4) No deforestation! Primary biomass For each of all 144 possible combinations (i.e. scenarios: Food secure, i.e. supply demand? Amount of spare land? Agricultural yields (3) FAO projection

5 Alternative Scenarios: Biophysical option space

6 Low (organic) yield scenarios 65% of FAO yield projection for 2050 Most scenarios not feasible due to limited cropland. Only in some scenarios with a rather high share of ruminant meat in diets and non-intensive livestock diet, grassland becomes (additionally) limiting. Global food security possible with less meat intensive diets and a nonintensive livestock diet.

7 High yield scenarios 109% of FAO yield projection for 2050 (MEA Technogarden ) Most scenarios feasible. In scenarios with diets converging globally to western standards and an intensive livestock diet, cropland areas become unsufficient. In scenarios with more ruminant meat and non-intensive livestock diets, grassland becomes limiting.

8 Rich Trend Moderate Frugal Organic Intermediate Trend (Fao) High (+9%) Energy crop potential [EJ/yr] Energy crop potential [EJ/yr] Dependency of energy crop potential 2050 (=spare land) on diet and agricultural technology Diet Cropland yields

9 Conclusions The feasibility of food security and the availability of spare land strongly depends on the combined development of consumption (i.e. diet) and agricultural technologies (i.e. yields and livestock). A reduction of the share of meat reduces biomass demand and therefore creates spare land that could be used for bioenergy production, carbon sequestration (i.e. afforestation) and/or extensification of land use. Increasing yields and/or livestock efficiencies only have the same effect, IF the increasing biomass production is not (literally) eaten up by richer (i.e. meat intensive) diets. More crop intensive and thus more efficient livestock diets are only preferable to the extent that cropland does not become the limiting factor.

10 Thank you for your attention! Contact for further information: An extensive description of methods and results can be found in: Erb, K.-H., Haberl, H., Krausmann, F., Lauk, C., Plutzar, C., Steinberger, J. K., et al. (2009). Eating the planet: feeding and fuelling the world sustainably, fairly and humanely - a scoping study. Commissioned by Compassion in World Farming and Friends of the Earth UK. Social Ecology Working Paper (p. 132). Social Ecology Working Paper No Available on Erb, K.-H., Mayer, A., Kastner, T., Sallet, K.-E. & Haberl, H. (2012). The impact of Industrial Grain fed Livestock Production on Food Security: an extended literature review. Social Ecology Working Paper (p. 132). Vienna: IFF Social Ecology. Available on