The first agricultural revolution took place between 10,000 and 200 BC. The first group of people to settle in one place for a long period of time , took place in the middle east. Humans began to settle in one place and started to cultivate the land by planting crops and raising livestock. The crops became domesticated. The shift from hunting and gathering transformed into agriculture and started the revolution of what was now the new civilization.
The second agricultural revolution began around 1815 and ended around 1880. There was Improved food production to feed more than a family or village. New fertilizer and artificial seed was introduced. Farming became much faster, easier, and more efficient once all of the newly invented machines were introduced. A lot of the new machines helped reduce human and animal labor and turn it into machine labor. http://hunterston.weebly.com/second-agriculture-revolution.html
The Third Agricultural Revolution occurred approximately 250 years after the second agricultural revolution. More intensive mechanization, chemical applications, and biotechnology. Gas and diesel engine tractors were introduced to made it easier and faster to plant and harvest crops. Machines used for farming have became larger, more powerful, and more efficient since the Second Agricultural Revolution. Reduced number of laborers, increased land and monoculture happened during the Third Agricultural Revolution.http://apcentral.collegeboard.com/apc/members/courses/teachers_corner/8651.html