In a world of 9.5 billion people, global demand for food, fiber, and biofuels has to be met with minimal possible increases in land, water, fossil fuels, and the minerals used to produce fertilizers. The problem is debated at three levels: first, that agriculture will not be able to produce enough because it will come up against both biophysical and environmental limits that restrict yields; second, that the need to expand and intensify agriculture will destroy the broader environmental values of forests, wetlands, marine systems, and their associated biodiversity; and third, that there are institutional obstacles to the diffusion and adoption of the innovations that could solve these problems.
Although there is debate on these issues, there is also strong consensus that we are witnessing unprecedented changes in our major agricultural systems. Major shifts are occurring in the way food and other agricultural commodities are produced, in the scale at which this happens, in the geographical locations of agriculture, and perhaps most notable, the agencies and actors driving these processes. Growth in demand for agricultural products will mainly occur in markets of emerging economies, particularly in the most populous countries of Asia and Sub-Saharan Africa. Therefore, the ways in which China, India, Indonesia, Bangladesh, Nigeria, Ethiopia, and South Africa respond to growing food demand will be major determinants of environmental change at a global scale.
The papers in this special feature of PNAS highlight innovations in agriculture that could contribute to producing more food without increasing environmental pressures. The papers are based on some of the more exciting ideas that emerged from a forum in Beijing in October 2011 that brought together agricultural and environmental scientists from China with their peers from the rest of the world.