Quick Answer. Neo-Malthusian theory holds that population growth is exponential and that human population growth can easily outstrip its food resources if not held in check with artificial birth control measures. It differs from traditional Malthusian theory in the proposed birth control solution.
Terrace farming is when farming is done on manmade terraces that have been built into slopes. When humans transform a slope into a series of flat surfaces, they form terraces. Crops are then grown on these flat surfaces rather than on the slope, preventing crops from sliding down the slope over time. The image below is of rice paddies grown on terraces. By building these terraces, water flows down and accumulates in each terrace. If the terraces did not exist, rainfall and water would flow from higher elevations down the hill/mountain, carrying important soil and nutrients with it. Building terraces prevents this from happening.
However farmers of Japan are the most productive farmers in the world because of their creative uses of the land, to maximize it's potential Industrial Age Urban-Rural Population Distribution: Urban populations:In countries like Japan undergoing the industrial revolution , people moved to cities to work in factories. In developing countries today, many people are moving to cities seeking (but not always finding) jobs and access to modern life, resulting in unmanageable cities and slums in many cases.