As discussed in previous chapters, it is expected that more than four-fifths of theincreased production to 2050 will come from existing land areas through increased productivity. Many systems are, however, already constrained either because of existing high productivity levels, or because there are technical, socio-economic or institutional constraints. In addition, as the intensity of farming increases, the risks and related tradeoffs discussed in the previous chapter become more pressing. 

This chapter reviews technical options for moving towards ‘sustainable land and water management’, that is - more intensive integrated management of soil, water, nutrients and other inputs to produce increased crop value whilst maintaining or enhancing environmental quality and conserving natural resources, both on-site and off-site.Even though the growth in the area of rainfed agriculture has remained static, rainfed agriculture is still projected to produce one third or more of the increase in global food output in the coming decades. Rainfed systems in temperate zones are already high yielding but face problems of nutrient and pesticide pollution. Smallholder rainfed systems in developing countries face far more problems of poor soil quality, soil moisture deficits, high levels of agro-climatic risk exacerbated by climate change. They are also hindered by the absence of profitable market outlets and the resources to invest in improving productivity.