Systems thinking on intensification and sustainability: systems boundaries, processes and dimensions

‘Sustainable intensification’ is gaining popularity among academics and donor agencies without much examination of the ambiguities in both terms, made worse by combining them. The terms can be made more serviceable by distinguishing between definitions by extension and definitions by intension . Difficulties with the term ‘intensification’ are addressed by considering the System of Rice Intensification (SRI). This reverses Green Revolution thinking about intensification as a matter of increasing material inputs. Changes in crop management can raise food output by reducing such inputs, with increased reliance on knowledge and management that use available resources more productively and sustainably. Its initial increases in labor inputs are usually transitory. Conjunctions of different disciplines and different levels of analysis and action are considered with reference to the factors of nestedness and contingence . Subjects bearing on sustainable intensification which can benefit from disciplinary convergence include: biogeochemistry to address problems of climate change; part-time farming to adapt to changing economic opportunities; and symbiotic endophytes that can enhance crop health and growth. The concept of ‘causation’ is disaggregated to consider ‘processual’ as distinguished from ‘mechanistic’ causation. Systems thinking is likely to be more productive for addressing interactions within and between subsystems rather than for theorizing about systems as a whole.