The nexus of food, energy, and water.

The Earth's population is expected to exceed 9 billion by 2050, posing significant challenges in meeting human needs while minimally affecting the environment. To support this population, we will need secure and safe sources of food, energy, and water. The nexus of food, energy, and water is one of the most complex, yet critical, issues that face society. There is no more land to exploit, and the supply of fresh water in some areas of the world limits the use of land for food. All solutions must also deal with the overlay of global climate change. Meeting current and future populations needs will require security in food, energy, and water supplies. A nexus approach is needed to improve food, energy, and water security integrating the management of the limited resources while transitioning to a more "green" economy, which provides adequate food, energy, and water for the expanding human population.