Science for sustainable agriculture

Modern agriculture, which underwent revolutionary progress to achieve its twentieth-century form, can be defined in a single phrase as “petroleumdependent agriculture”. Inexpensive fossil fuels are used to operate large machinery, which enables large-scale cultivation, mono-cropping, standardization and high-volume transport; and the synthesis of fertilizers and agricultural chemicals permits the improvement of soil fertility and simplified management of ecosystems. Until the nineteenth century, agriculturalists were basically forced to engage in stable sustainable agriculture that took maximum advantage of nature’s functions. But during the twentieth century, by taking full advantage of the energy sources provided by inexpensive fossil fuels, “using natural functions” gave way to “applying technology to transform nature”. This form of agriculture is referred to as the modern agricultural revolution because its basic technologies were established at the start of the twentieth century, permitting a great leap in production. The modern agricultural revolution is characterized by (1) the mechanization and increased scale of agriculture, with high-volume transport made possible by motorization using fossil fuels (petroleum) to power internal combustion engines; (2) the management of soil fertility and ecology using chemical fertilizers and agricultural chemicals; (3) the development of high-yield varieties; (4) advanced water management in some regions; and (5) remarkable increases in labour productivity as a result of the first four characteristics. During the late nineteenth and early twentieth century, the basic technologies for motorization through the use of gasoline to power internal combustion engines were established. Also, Fritz Haber and Carl Bosch developed the technology to produce ammonia by fixing atmospheric nitrogen gas. The Haber–Bosch process is a method of producing ammonia using an iron oxide catalyst to trigger a reaction of nitrogen gas and hydrogen gas under supercritical conditions, 300–550°C and 15–25 MPa. Thanks to this process, it is now possible to manufacture the nitrogen fertilizers that play a crucial role in agriculture. In this way, the fundamental technologies for modern agriculture were almost entirely established in the late nineteenth and early twentieth century. One more important factor in the development of petroleum-dependent agriculture was crop yield improvement technologies based on large-scale fertilization and the breeding of extremely highyielding varieties. These varieties included Norin 10 wheat and Yukara rice, which were bred by Japan in the 1950s and successfully contributed to heavier yields of tropical wheat and rice, an event called the Green Revolution.

الموضوعات ذات الصلة: Environment and Climate Change