The Sustainability of Rice Farming
Rice is the world’s most important crop. It has supported more people for more years than any other cereal. The great civilizations of Asia emerged in the broad river deltas of China. Southeast Asia and the Indian subcontinent because high yields of rice sufficient to support more than the food demands of those who produced it could be sustained. The importance of rice in Asia is such that it has become deeply entwined with the cultures of the region. The terraced systems by which water is channelled to the small fields in which rice is grown have characterized the Asian landscapes for many years.
The reasons why rice has been able to support so many for so long are due to the physical environment in which rice is grown. The high rainfall of the monsoon lands, and the fact that nutrients and fertile sediments are carried with the floodwaters that seasonally flow into these areas, provided the essential requirements of the crop from the time that it was first cultivated several thousand years ago until recently. But now the burgeoning population of Asia has outstripped the natural capacity of the rice areas to produce the flow of nutrients and water that are the essential requirements of the crop. Nutrients now have to be supplied using heavy dressings of inorganic fertilizers, and flood waters stored behind huge dams for later release to the rice fields. Rice varieties able to produce greater yields than any grown before have been bred. These changes have averted the famines which afflicted India, China and other densely populated parts of Asia in the past and which were predicted to do so on an even wider scale in the 20th century. While the earlier methods of rice production proved sustainable for millennia the sustainability of the new methods of production. giving much greater yields, has still to be established.