This is part 1 of A Climate Counternarrative.
Land stewards often understand that topsoil loss contributes significant amounts of carbon dioxide to the atmosphere. Soil emissions dwarf industrial ones, after all. But farmers have been disturbing soil since long before the industrial era, so they’re hard pressed to precisely explain what changed around then.
Topsoil loss is a concern irrespective of the climate narrative. It matters if you value healthy food grown in thriving ecosystems. It makes sense to promote gardening, urban agroecology, and regenerative farming on that basis alone, in fact. Climate activists would be more effective promoting these, because doing so has no downsides and depends on no one.
Prompting climate activists to promote these activities is also a great way to make them (unwittingly) work against those who advocate eating bugs. Activists are typically on board with gardening and regenerative farming already. Teaching gardening at schools or getting into urban or peri-urban farming are very effective ways to promote using less fossil fuels. Simply bring that up. More food sovereignty won’t hurt your community. And as we’re about to discuss, regenerative farming is enough to turn around the rise in atmospheric carbon dioxide.
At the same time, regenerative farming can build soil without addressing the key reason topsoil ends up in the atmosphere. Research on forestry emissions inadvertently reveals what that is.
Briefly, a cleared forest releases a slow-motion plume of carbon dioxide as forestry waste decomposes. Researchers detect these using instruments that monitor net flows above the canopy. This continues until the new canopy has grown enough to soak that up. By contrast, thinning a forest leaves the canopy intact. That avoids these releases to begin with.
This highlights three things that happen when you clear a field. (1) You remove the canopy above ground. (2) You leave behind organic waste that decomposes. (3) Plants soak up the resulting soil emissions.
Land stewards have been removing the plants that offset these soil emissions since the industrial era.
Loggers adopted clear-cutting at the turn of the 20th century. A cleared forest is a wide open field. The soil fungi, which need plants for sugars, eventually die. The wind takes the soil emissions up in the atmosphere before nearby plants soak them up.
From the 19th century onward, farmers began managing ever larger fields as family farms vanished, land changed hands, and factory farming took off. They removed hedgerows that limited tillage erosion while keeping the soil fungi alive, breaking the wind, and soaking up the soil emissions.
Changes also happened in places that had little or no tree canopy to begin with. American settlers moved West just as steel plows made it practical to till the Great Plains, for instance. Wide open farm fields and overgrazed paddocks soon replaced large swaths of prairie. Dead waters might also be emitting their soil carbon in shallow areas — if only as methane.
Curbing these plumes of carbon dioxide is straightforward. When you clear a field, leave plants around to soak up the soil emissions. A simple way to do that is alley cropping. The alleys can be wide enough to not block sunlight, if the ancient fields that dairy cows continue to graze in Normandy are an indicator. Planting directly into clover and other well designed intercropping systems would work too.
It follows that farmers could stick with planting rows of coppice trees on contour to avoid these plumes. Doing so offers many benefits. Trees act as windbreaks, which slows down pests. Trees on contour help water soak in, which reduces the need to irrigate. Leaves and tree roots release nutrients when they decompose. Short-cycle coppicing ensures the trees won’t burden nearby crops. Biomass is a renewable energy source. The diversified revenue and the lower input costs typically make alley cropping profitable. And it’s a stepping stone for farmers to go regenerative.
Better yet, farmers could restore wildlife habitat by semi-managing narrow bands around these trees like roadsides. There are better ways to address biodiversity loss, like food forest gardening, syntropic agroforestry, or mob grazing. At the same time, rewilded gardens, roadsides, creeks in logged areas, and other examples show that small patches and narrow bands left to nature, while far from ideal, are good enough. They’re the ecosystem equivalent of feeding a caged animal just enough to not starve.