New and growing demands for sustainable use of natural resources are having a serious impact on agriculture, as the sector struggles to feed a growing world population, according to Louise Fresco, Assistant Director-General of the UN Food and Agriculture Organization (FAO). Speaking at the opening session of a major pan-African conference on water for food and ecosystems, Ms Fresco said: "The history of agriculture is characterized by a progressive and increasing control of the biological processes for the sake of increased food production."