The soil-plant systems and the carbon circle

Transkript

1 The soil-plant systems and the carbon circle Workshop 15. november 2013 Bente Hessellund Andersen

2 The soil-plant systems influence on the climate

3 Natural CO 2 -sequestration

4 The soil-plant systems influence on the climate

5 What kind of agriculture? Increasing emissions from land use 1700: Estimated carbon content in the atmosphere 580 billion tonnes Today: Estimated carbon content in the atmosphere 760 billion tonnes Land-use changes are estimated to have contributed billion tonnes More if carbon from the vegetation is included Soil Carbon Dynamics. An Integrated Methodology, Kutsch m.fl., Cambridge University Press, 2009

6 Jorden år 1700 UNEP GEO 3 (Global Environment Outlook 2002)

7 Jorden år 2002 UNEP GEO 3 (Global Environment Outlook 2002)

8 What kind of agriculture? Increasing emissions from land use

9 What kind of agriculture? Increasing emissions from land use Global estimations on emissions of GHG from agriculture (% of total) (Data from 2000) : On-the-farm activities in the primary agriculture: 15% of the global emissions of greenhouse gasses. Emissions related to land-use and land-use changes are not included. In developed countries, land-use-change has already occurred and, therefore, does not contribute largely to the emissions. In developing countries, land-use-change is estimated to contribute with 33% of emissions I the least developed countries, land-use-change is by far the most important contributor, estimated to be 62%.

10 CO 2 -emissions from land-use changes

11 Industrial agriculture and the industrial food system are major causes of the climate crisis GRAIN s estimations regarding global emissions from agriculture and the food chains: Agricultural activities are responsible for 11 to 15% Land clearing and deforestation cause and additional 15 to 18% Food processing, packing and transportation cause 15 to 20% Decomposition of organic waste: 3 to 4% Total emissions of the food system: 44 to 57% of total global greenhouse emissions

12 Fast destruction of soils GRAIN s estimations: In the last 50 years, the massive use of chemical fertilizers and other unsustainable practices of industrial agriculture have caused an average loss of at least tonnes of soil organic matter for every hectare of agricultural land. The total loss amounts to: billion tonnes of organic matter

13 GRAIN s climate calculation Amount of organic matter lost from the soils in the past 50 years: billion tonnes Amount of CO2 that would be sequestered from the atmosphere if these losses were recuperated: 220 to 330 billion tonnes Current excess CO2 in the atmosphere: Rebuilding soil fertility to pre-industrial levels would capture 30-40% of current excess of CO2 in the atmosphere

14 Yields on farm land: To increase every year by 0.7 % (how? GMO?) What kind of solutions? Intencification For instance (Danish Climate Commission 2010): Yields dairy cows: 2010: kg milk 2050: kg milk Yields sows: 2010: 25 piglets per year 2050: 35 piglets per year

15 What kind of solutions??

16 Brug af jordens overflade Natur Bioplast Fødevarer Tekstiler Biodiversitet Foder Tømmer Brænde Biobrændsler Papir

17 Brug af jordens overflade Natur Bioplast Fødevarer Tekstiler Biodiversitet Foder Tømmer Brænde Biobrændsler Papir

18 Brug af jordens overflade Natur Bioplast Fødevarer Biodiversitet Tekstiler Foder Tømmer Brænde Biobrændsler Papir

19 Én jord til hvad? til hvem?

20 2032 markedet har 1. prioritet UNEP GEO 3 (Global Environment Outlook 2002)

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29 Certificering en løsning?

30 Brug af globale resurser vs. bæredygtighed Mængden er problematisk for klima, miljø (vand, biodiversitet ) og fødevaresikkerhed. Det er ikke muligt at forebygge de uønskeder konsekvenser fra en øget produktion af bioenergi ved at opstille krav om bæredygtighed (certificering) Det hjælper ikke at den individuelle mark måske er bæredygtig, hvis den samlede efterspørgsel vokser => Bæredygtighed kan ikke sikres, hvis der ikke sættes grænser men vi ser det modsatte: efterspørgslen definerer hvad der er bæredygtigt

31 A world invaded by plantations (in millions of hectares) soybeans oil palm sugar cane tree plantations 5,5 18, ,2 22,7 185 Monokultur plantager optager I dag mere end 20% af den opdyrkede jord (GRAIN)

32 1700 UNEP GEO 3 (Global Environment Outlook 2002)

33 2002 UNEP GEO 3 (Global Environment Outlook 2002)

34 2032 the market has first priority UNEP GEO 3 (Global Environment Outlook 2002)

35 2032 sustainability has first priority UNEP GEO 3 (Global Environment Outlook 2002)

36 TAK