Agriculture is now entering a 'third wave of modernity'. The first wave took place in the late 19th century, with the abolition of the Corn Laws and the Navigation Act in Britain. This began an era of free trade and a rapid development of agronomic science, involving new technologies and methods in agriculture. A second wave of modernity began after World War II – again based on the ideals of free trade within Europe and bringing further technological advance. This second wave continued until recent years – perhaps until the 1992 CAP reform and the last GATT agreement. The third wave, which is now gathering speed, consists of the rapid adoption of new bio-technologies, globalisation of agriculture and the growing move towards international free trade.
All agricultural production represents an intervention to the natural ecosystem in order to provide food and fibre in a productive and cost-effective manner. To be sustainable, production systems must prove their ability to maintain a certain level of productivity without the threat of long-term damage or degradation to the environment or resource base.
Climate change is likely to result in considerable global shifts in farming practice. Planning for these changes should also consider water demands, which will inevitably change with climate change, increased human populations, and increased water use. In areas of anticipated severe shortages, restoring natural habitats that do not require irrigation might be a sensible means of reducing demand. In return, appropriate soil management and forestry can sequester carbon and reduce the production of greenhouse gases.