[Extensive plant production: Environmentally sound activities: the autumn conference 1993 [biodiversity]]

agricultural policies agriculture biologique agriculture extensive chemical control ciencias forestales crop yield danemark denmark dinamarca extensification extensive farming fallow systems faune et flore sauvages foresterie forestry landscape leaching lessivage du sol lutte chimique organic farming paisaje paysage plant production politique agricole rendement des cultures rendimiento de cultivos sistemas con barbecho vida silvestre wildlife