Soil is the biggest brake on global heating. It holds more carbon than the atmosphere and all standing vegetation together but farmers have been burning off soil organic matter for 12000 years: they are responsible for one-third of greenhouse gas emissions. The best thing they could do for the planet is to put it back again, and the best place to start is the best soil in the world – the Black Earth of the steppes, prairies and pampas. Half of its organic matter has been pumped into the air and 35 years of satellite measurements reveal a significant loss of primary productivity across the steppes. Conservation Agriculture can haul back the carbon deficit, increase yields and save 60–70% on fuel, fertiliser and labour; the green biomass can support livestock and/or generate biogas. Ukraine and Moldova were set to adopt this system and phase out their coal-fired power stations when the Russian army invaded Ukraine. The best soil in the world is now being put to other uses; we face a global food crisis; and the world’s decision makers have yet another excuse to defer serious efforts to mitigate climate change.

Land degradation is holding back attainment of the Sustainable Development Goals and exacerbating global heating. Land degradation and improvement since 1981 have been assessed by proxy using remotely sensed Normalised Difference Vegetation Index (NDVI), translated into net primary productivity. The quantitative data show the extent and trends of changes over four decades and identify where further action is needed. During 1981–2021, 28.5% of land was degrading—most notably through megafires in boreal forests, land clearance and cultivation in sub-Saharan Africa and the East Indies and across the steppes. The degraded area increased by 4.5% compared to 1981–2003 yet affected fewer people—1.2 billion compared to 1.5 billion. Consistent policies on sustainability increased biological productivity on 26% of land (10.5% more than 1981–2003), particularly cropland in China, India and the European Union; 2.9 billion people now live in the improved areas compared with 0.8 billion in the improving areas of 1981–2003.

(2020). Advances in conservation agriculture. International Journal of Environmental Studies. Ahead of Print.