P. K. Ramachandran Nair is an Indian American agricultural scientist, Distinguished Professor of Agroforestry and International Forestry at the School of Forest Resources and Conservation, University of Florida. He is known for his pioneering contributions to the science of agroforestry, for which he received global recognition including the Humboldt Prize (2006). The specific areas of his research include: agroforestry in the tropics and subtropics, integrated farming systems, soil carbon sequestration and climate change mitigation, ecosystem services, and soil fertility management. He has written over 200 peer-reviewed articles, 17 books and over 75 book chapters.