Agroecology can be defined as a range of agricultural practices that are based on applying ecological concepts and principles to optimize interactions between plants, animals, humans, and the environment. Agroecology also places strong emphasis on the social and ethical aspects of food production. Its advocates tend to have a preference for organic practices (e.g. the avoidance of mineral fertilisers and chemical inputs, and instead prefer the use of biofertilisers, natural pesticides and crop rotation), it also emphasises the need for a ‘multifunctional’ farm system to produce both food and non-food outputs, and for smallholder and indigenous, as opposed to large scale farming. Agroecology has been interpreted in different ways: it also refers to a social movement and field of science.