Chapter Fifteen: Food and Agriculture

Section One: Feeding the World Humans and Nutrition Famine: widespread starvation caused by a shortage of food Malnutrition: a condition that occurs when people do not consume enough calories or do not eat a sufficient variety of foods to fulfill the body’s needs You need carbohydrates, fats, proteins, and amino acids Diet: the type and the amount of food that he or she eats Diets vary by regions and by what foods are available

Section One: Feeding the World The Ecology of Food How efficiently can it be grown? More energy, water, and land is used to create food from animals than plants Yield: the amount of food that can be produced in a given area

Section One: Feeding the World World Food Problems Poverty Malnutrition results from it Africa, Asia, and South America More Income and More Food If we can abolish poverty, we can abolish malnutrition

Section One: Feeding the World The Green Revolution Larger yield without more land usage Reduces the price of food and improves lives

Section Two: Crop and Soil Agriculture: Traditional and Modern Arable: land that can be used to grow crops Traditional Agriculture Plowing the land, manure as fertilizer, field are irrigated by rain and water in ditches, weeds are removed by hand Modern Agriculture Machinery is used for all processes and synthetic chemicals are used

Section Two: Crop and Soil Fertile Soil: The Living Earth Topsoil: the surface layer of the soil rich in organic matter

Section Two: Crop and Soil Soil Erosion: A Global Problem Erosion: the movement of rock and soil by wind and water Half of the topsoil is lost to erosion If we lose topsoil we cannot grow crops Land Degradation Happens when human activity or natural processes damage the land so that it can no longer support the local ecosystem Desertification: the process by which land in dryer areas becomes desertlike

Section Two: Crop and Soil Soil Conservation Building terraces to prevent downhill erosion Contour plowing: plowing across hill slopes No-till farming: harvesting without tilling the land Enriching the Soil Traditional farming used organic matter We now use fertilizers Compost: partly decomposed organic material Salinization The build up of salts in the soil Prevents plants from growing

Section Two: Crop and Soil Pest Control Insects eat 13% of crops Pests include insects, fungi, plants, and microorganisms Pesticides Chemicals used to kill insects, weeds, and other crop bests Pesticide resistance can develop Can be dangerous to humans Persistent pesticides do not break down rapidly and can build up in the water and soil

Section Two: Crop and Soil Biological Pest Control the use of living organisms to control pests Using a pest’s natural enemies Disrupting insect breeding Can use pathogens or building up plant’s defenses Can build up their physical characteristics or can use chemicals found in other resistant plants

Section Two: Crop and Soil Integrating Pest Management Reduce pest damage to a level that causes minimal economic damage Engineering a Better Crop Farmers use selective breeding Genetic engineering: the technology in which genetic material in a living cell is modified for medical or industrial use. Used to transfer resistance

Section Two: Crop and Soil Sustainable Agriculture Farming the conserves natural resources and helps keep the land productive Minimizes the use of energy, fertilizers, pesticide, and water

Section Three: Animals and Agriculture Domestication: the process of animals being bred and managed for human use Food from Water Fish are harvested Overharvesting: catching or removing from the population more organisms than the population can replace

Section Three: Animals and Agriculture Aquaculture The raising of aquatic organisms for human use or consumption Catfish, oysters, crayfist, salmon and rainbow trout Requires lots of water

Section Three: Animals and Agriculture Livestock Domesticated animals that are raised to be used on a farm or ranch or to be sold for profit Poultry Ruminants: cattle, sheep, and goats Have a three or four chambered stomach