Soil Carbon

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I discovered this old slide, once used to teach Biogeochemistry 101 at CU Boulder. Its a map of soil organic carbon (SOC) turnover time: the amount of time it takes to fill or empty the carbon reservoir of an ecosystem (Schimel et al. 1994). ⠀

The carbon reservoir of any ecosystem is filled by plants absorbing CO2 out the atmosphere and emptied by microbes eating organic matter and exhaling CO2 back into the atmosphere. Temperature and rainfall are the overriding controls on these processes. The map shows fast turnover in tropical ecosystems because the climate is optimal for plant and microbial growth, whereas boreal and tundra ecosystems are slow to grow and decompose. In virgin ecosystems, the inflow and outflow of CO2 is roughly in balance. ⠀

Yet, the equation changes dramatically when we start cutting trees for pulp and lumber, tilling the soil, irrigating, removing or introducing animals to the land, and more often than not, using 'natural resources' releases massive amounts of soil carbon to the atmosphere. Now, the challenge is to figure out ways to get CO2 back into the ground. Doing this requires an understanding of what controls soil carbon storage, and lots of love and care. We've learned a lot since this map was published 23 years ago. Yet, this map is just the beginning; at finer spatial and time scales, all sorts of things matter: minerals, microbes, management regime, markets, etc. ⠀

Here are some brilliant folks (to name a few) bringing soil to the heart of humanity, where it belongs. ⠀

@soilsolutions @fibershed_@kissthegroundca @whiteoakpastures@kanedan29 @soil.life @noblegrainalliance@flyingplow @patagoniaprovisions@projectgrounded @wildfarmpermaculture@soil4climate @thehonestbison@theecologycenter @theperennialsf@projectdrawdown @rodaleinstitute@drbronner @stonebarns @jackalgiere@whendeesilver @ryals.agroeco.lab@emmerandco @tomkatref@homeplacepastures @belcampomeatco@modfarm @modesto_milling @ansonmills@centerforfoodsafety @civileats@jasperhillfarm @lineageseeds@justin.sandy @blackcatboulder@maxfields_organics @wsu_bread_lab@johnnys_seeds @singingfrogsfarm@vermontcompost @hawthornevalley@youngfarmers @youngagrarians

Philip TaylorComment