“Taking planetary nutrient boundaries seriously: Can we feed the people?”
Nutrient flows in the earth system are instrumental to food security. Increase in the flows of nutrients is linked with climate change and the loss of biodiversity, those being the three human-induced shifts that have led to overstepping the ‘planetary boundaries’ (Rockström et al., 2009a and Rockström et al., 2009b) or ‘the upper tolerable limits’ (Carpenter and Bennett, 2011) of the regulatory capacity of the earth system. We cannot afford to risk the vital processes of the earth, but can we feed the world population within these boundaries?
The global demand for food is rapidly increasing. The world’s population has been projected to plateau at nearly ten billion people by the middle of this century and to peak at eleven billion by the end of the century (UN, 2011). Simultaneously, there is increasing competition for critical resources such as land, biomass, energy and phosphorus (P) reserves. The challenge of feeding the people is even more striking because it must be met when the critical biophysical boundaries for several earth system processes that determine elementary ecosystem services have been transgressed or are on the verge of becoming transgressed (Rockström et al., 2009a and Rockström et al., 2009b). Flows of reactive nitrogen (N) and P represent one such process; excessive nutrient flows cause eutrophication and exacerbate biodiversity loss and N flow exacerbates climate change…
To read the full study, please click here: http://www.sciencedirect.com/science/article/pii/S2211912413000540