The Soil Carbon Manifesto
12. oktober 2008
Den anden dag faldt jeg over The Soil Carbon Manifesto (se nedenfor), skabt af den australske organisation Carbon Coalition Against Global Warming. Det er et spændende område, som jeg meget gerne vil trænge meget mere ind i. Dels fordi der ligger et stort CO2-bindingspotentiale i rigtig brug af vores landbrugsarealer, dels fordi det samtidig kunne være nøglen til et landbrug, som producerede langt sundere fødevarer.
Set i dette perspektiv er vores nuværende afbrænding af alt affald dybt problematisk. Stadig føler jeg efter at have boet 28 år i København et lille stik af smerte når jeg dagligt må lade god jordernæring, som burde komposteres, gå i affaldsspanden. Så vidt muligt burde alt det organiske affald fra restauranter, husholdninger og næringsmiddelindustri komposteres og bringes tilbage til landbruget som en livgivende erstatning for de CO2-tunge kunstgødninger, hvoraf en alt for stor del i dag udvaskes med voldsomme forstyrrelser af vandmiljøet til følge.
Michael Braungart fortalte for nylig på vugge til vugge-konferencen her i København, at det industrielle landbrug hvert år tærer på muldlaget svarende til, hvad det har taget 5.000 år at opbygge. Hans ærinde var, at det er vitalt for opretholdelsen af landbrugsarealernes vækstkraft – og for bæredygtigheden – at langt det meste af det, der blev høstet fra markerne, kom til tilbage til markerne som organisk materiale.
Og hvis vi skal lykkes med ikke bare at få bremset CO2-ophobningerne i atmosfæren, men igen at få koncentrationerne ned på omkring 350 ppm, er vi nødt til ikke bare at ophøre med den fossile afbrænding, men systematisk at arbejde på at øge CO2-bindingen i biosfærens muld og vegetation.
Carbon Coalition Against Global Warming har som mål at etablere en CO2-kvoteordning for det australske landbrug – en såkaldt carbon farming – hvor man gennem ændrede dyrkningsmetoder kan binde store mængder CO2 i muldjorden. Rigtigt tilrettelagt kunne det blive et økonomisk incentive, som kunne stimulere en bred omlægning til økologisk landbrug med bæredygtigt husdyrhold og stærkt reduceret forbrug af pesticider, kunstgødning og fossile brændstoffer. Det vil dog forudsætte, at perspektivet sættes videre end blot og bar CO2-reduktion.
Men her er kommer koalitionens Soil Carbon Manifesto:
The Soil Carbon Manifesto
Carbon Coalition is a group of concerned Australians who believe the globe is facing a crisis of CO2 overload leading to Global Warming and that one of the most effective strategies for locking up carbon in our atmosphere is to be found in fostering deep-rooted plant species on land used for agriculture.
Capturing more carbon in agricultural soils will mean water is used where it falls, leading to cleaner waterways and less silting.
We urge governments and the business community to acknowledge the role that agricultural soils can play in addressing the Global Warming crisis. Farmers can play a central role in sequestering carbon in their soils by fostering deep-rooted perennial plant species that have significant biomass in their root systems.
Soil biomass is a natural carbon sink and should be used to create carbon credits which can be traded alongside those currently traded for forests.
Soils Can Save the World
We stand by the following facts:
• The terrestrial biosphere currently sequesters 2 billion metric tons of carbon annually. (US Department of Agriculture)
• Soils contain 82% of terrestrial carbon
“Enhancing the natural processes that remove CO2 from the atmosphere is thought to be the most cost-effective means of reducing atmospheric levels of CO2.” (US Department of Energy)
• “Soil organic carbon is the largest reservoir in interaction with the atmosphere.” (United Nations Food & Agriculture Organisation) – Vegetation 650 gigatons, atmosphere 750 gigatons, soil 1500 gigatons
• The carbon sink capacity of the world’s agricultural and degraded soils is 50% to 66% of the historic carbon loss of 42 to 78 gigatons of carbon
• Grazing land comprises more than half the total land surface
• An acre of pasture can sequester more carbon than an acre of forest
• “Soil represents the largest carbon sink over which we have control. Improvements in soil carbon levels could be made in all rural areas, whereas the regions suited to carbon sequestration in plantation timber are limited.” (Dr Christine Jones)
Benefits for the Nation and the Economy
The benefits of rewarding farmers for contributing to carbon sequestration include the following:
• Improved soil health, protecting our most precious national resource
• Increased soil fertility, boosting productivity and competitiveness
• Better usage of water, reducing erosion, silting, and salination
• Reduced danger of rising salt levels, lowering the water table
• Reduced loss of topsoil to wind and runoff with 100% ground cover
• Increased farm incomes, increasing viability in volatile industries
• Increased farm values, giving farm families financial flexibility
• Foster growth in farm communities, providing employment opportunities and protecting social infrastructure
Robert E. Pettit: Organic Matter, Humus, Humate, Humic Acid, Fulvic Acid, and Humin, 02.04.2006.
Christine Jones: Grazing Management for Healthy Soils, 24.03.2006.
Christine Jones: Soil Carbon’s impact on water retention, marts 2006.
Christine Jones: Carbon Stops Salt, 02.04.2006.
Christine Jones: Creating topsoil, 24.03.2006.
Christine Jones: Soil Carbon and Carbon Credits, 05.03.2006.
