Save Our Soils

Many researchers focus on how to intensify agriculture for a growing, hungry world. So far, they have largely dodged the question of how global soils will cope. Our planet’s soils are under threat, as witnessed in the past decade by dust-bowl conditions in northwest China, the desertification of grasslands in Inner Mongolia and massive dust storms across north-central Africa. Soil losses in some locations around the world are in excess of 50 tonnes per hectare in a year1: up to 100 times faster than the rate of soil formation. In other words, we are losing nearly a half-centimetre layer of this precious resource per year in some places (see graphic).At the same time, global growth in human population and wealth requires a major intensification of agricultural production to meet an expected 50% increase in demand for food by 2030, and possibly a doubling by 20502. These numbers do not bode well. Scientists need to develop a predictive framework for soil loss and degradation quickly, to evaluate potential solutions systematically and implement the best ones. There is a way forward. In the past four years, a global network of research field sites — Critical Zone Observatories — has been established. Multidisciplinary teams are focusing on the fundamentals of soil production and degradation, and aiming to create quantitative, predictive models. This programme has enormous potential. It can and should be accelerated, with stronger collaboration between national programmes and strong links to policy-makers.