Agricultural operations are sustainably managed, they can preserve and restore critical habitats, help protect watersheds, and improve soil health and water quality. Negative externalities include the pollution of water bodies from nitrate leaching and human health impacts, such as pesticide poisoning. On the other hand, positive externalities from farming, such as community cohesion and the maintenance of livelihoods for smallholder farmers, are often undervalued.The impact of so many humans on the environment takes two major forms: consumption of resources such as land, food, water, air, fossil fuels and minerals and waste products as a result of consumption such as air and water pollutants, toxic materials and greenhouse gases. Environmental factors that influence the extent of crop agriculture are terrain, climate, soil properties, and soil water. It is the combination of these four factors that allow specific crops to be grown in certain areas.