and many experts considered it unrealistic to try to be. Due to North Korea's terrain, farming is mainly concentrated among the flatlands of the four western coastal provinces. This allows for a longer growing season, leveled land, substantial rainfall, and well-irrigated soil which permits the high cultivation of crops. Along with the western coastal provinces, fertile land also runs through the eastern seaboard provinces. However, interior provinces such as Chagang and Ryanggang are too mountainous, dry, and cold to support farming. In the 1980s, the Soviet Union embarked on political and economic reform. It began to demand that North Korea repay the Soviet Union for all of the past and current aid which it sent to North Korea – amounts which North Korea could not repay. By 1991, the Soviet Union dissolved, ending all aid and trade concessions, such as cheap oil. Without Soviet aid, the flow of imports to the North Korean agricultural sector ended, and the government proved to be too inflexible to respond. Energy imports fell by 75%. The economy went into a downward spiral, with imports and exports falling in tandem. Flooded coal mines required electricity to operate pumps, and the shortage of coal worsened the shortage of electricity. Agriculture reliant on electrically-powered irrigation systems, artificial fertilizers and pesticides was hit particularly hard by the economic collapse. Most North Koreans had experienced nutritional deprivation long before the mid-1990s. The country had reached the limits of its productive capacity, and could not respond effectively to exogenous shocks. North Korea's state trading companies emerged as an alternative means of conducting foreign economic relations. From the mid 1980s, these state trading companies became important conduits of funding for the regime, with a percentage of all revenues going "directly into Kim Jong-il's personal accounts... [which have been] used to secure and maintain the loyalty of the senior leadership". The country soon imposed austerity measures, dubbed the "eat two meals a day" campaign. These measures proved inadequate in stemming the economic decline. According to Professor Hazel Smith of Cranfield University: Without help from these countries, North Korea was unable to respond adequately to the coming famine. For a time, China filled the gap left by the Soviet Union's collapse and propped up North Korea's food supply with significant aid. By 1993, China was supplying North Korea with 77 percent of its fuel imports and 68 percent of its food imports. Thus,