Agriculture is not what it was — and, given that the global population is also not what it was, that may seem a good thing. Since the middle of the last century, new crop varieties, new cultivation techniques and new technologies have brought about a revolution in productivity: the average hectare, for example, now yields three times the tonnage of cereals that it did in 1961, according to Our World in Data.
But whether this is sustainable is a different matter. The costs that the modern food system imposes — in terms of deforestation, greenhouse gas emissions, biodiversity and human health — are becoming clearer year by hotter year. Brazil provides a case in point: an agricultural powerhouse, it may also be nearing a catastrophic ecological tipping point beyond which its rainforest cannot regenerate.