Changing the Farming Paradigm

Abstract

Two giants of the nineteenth century, Dokuchaev and Liebig, established very different approaches to the world of the soil: one in the field, the other in the laboratory. Dokuchaev’s idea of soil as an independent natural body developing in its own time according to its own laws, has resonance in James Lovelock’s Gaia hypothesis. Liebig’s acclaimed Theory of Mineral Nutrition was based on chemical analysis of plants and soil; later in life, he learned better but his followers did not. He also perceived a link between the health of the soil, the ecosystem and human health, followed up by Haeckel at turn of the century, Howard in the 1940s, and many others. Politics demands cheap food : there is nothing more expensive. After the Second World War, a deft sidestep by the chemical industry, from munitions to agrochemicals , brought fertilizers and pesticides to the fore: the Green Revolution was spawned not only by new crop varieties and hybrids but by cheap power, chemicals and expansion of irrigation . This paradigm depends on fossil energy to the point that it expends more energy than it produces. It is mining the soil organic matter that fuels life in the soil and maintains the architecture that allows infiltration of rainfall , water supply to plants and drainage to streams and groundwater . This loss cannot be made good by mineral fertilizers but only by annually returning enough fresh organic residues and farmyard manure . Food production is unequally spread: most countries rely on imports and the projected human population in 2050 will require a 50–70% increase in production. Farm-gate prices have been forced down while the cost of inputs rises. The response has been bigger farms, bigger machinery, indiscriminate use of agrochemicals , and a smaller workforce. Sustainability demands replacement of this broken system by a systemic approach mimicking natural ecosystems : organization of the landscape according to the shape of the land; the least possible soil disturbance, retention of crop residues as mulch , diverse crop rotations ; integration of crops and livestock ; and translation of science into action for rural communities. Long-term field experiments began at Rothamsted in 1843, others followed and painstaking measurements reveal the damage brought about by modern farming systems . But a different way of doing things arose not from formal experiments but from farmers themselves. In 1943, Faulkner had the gall to oppose ploughing but, from the 1970s, zero tillage was extended into Conservation Agriculture (CA) by farmers in Brazil—as a matter of survival. CA has now been adopted by some 14% of all cropland but lowering the barriers to adoption will need constructive policies and interdisciplinary research .

Scientific enquiry takes place in the context of the shared, the accepted … (the paradigm = normal science) punctuated by periods of hysteria out of which a new paradigm emerges—when normal science is resumed.

The structure of scientific revolutions. Thomas Kuhn 1962.