been transformed from almost closed, self-sufficient systems with few locally produced inputs geared to satisfy local requirements, to intensive, open systems, utilizing large quantities of energy-rich inputs such as fossil fuel for manufactured agro-chemicals, water distribution and imported animal feedstuffs to produce a range of sophisticated products, often for export, which in tum require many energy-rich inputs for their marketing. This industrialization of agriculture has proved to be very successful in many respects and indeed was accepted as a general model for agricultural development allowing increased productivity and efficiency per unit land, labor and water, even in areas with limited natural resources.