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Food and Agriculture. Ms. Hubbuch Chapter 15 The Howard School. How do we feed the world?. A diet is the type and amount of food that a person eats. Our bodies use food as both a source of energy and as a source of materials for building and maintaining body tissue .
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Food and Agriculture Ms. Hubbuch Chapter 15 The Howard School
How do we feed the world? • A diet is the type and amount of food that a person eats. • Our bodies use food as both a source of energy and as a source of materials for building and maintaining body tissue. • We receive carbohydrates, proteins, lipids, vitamins and minerals from our diet.
How do we feed the world? • People worldwide generally eat the same major nutrients and the same basic kinds of food. • In more developed countries people consume more food and a larger proportion of protein and fats. • The planet Earth could support 10 billion people on a strictly vegetarian diet!
How do we feed the world? • Poverty often leads to malnutrition, a condition that occurs when people do not consume enough calories or do not eat a variety of foods to fulfill needs. • A famine occurs when there is widespread starvation caused by a shortage of food. • Famines can be cause by lack of rain, loss of soil or war.
How do we feed the world? • In determining food efficiency, we measure the quantity of food produced on a given area of land. • Efficient foods higher yield with less negative impact on the environment. • Yield- the amount of food that can be produced in a given area. • Plants are for more efficient foods than animals.
How do we feed the world? • Subsistence farmers grow only enough food for local use. • They are generally restricted by limited resources and only grow enough to feed their family.
How do we feed the world? • Between 1950-1970, Mexico increased its production of wheat and India doubled its production of rice without using more land. • The Green Revolution improved lives and reduced the price of food. • This resulted from new varieties of grains that required more water, fertilizer and pesticides.
Agricultural Practices • In traditional agriculture, plows are pushed by the farmer or pulled by livestock, organic fertilizers are used, fields are irrigated by ditches and weeds are removed by hand. • Modern agriculture utilizes machinery powered by fossil fuels to plow, synthetic chemical fertilizers, drip systems for irrigation and synthetic chemicals to kill weeds.
Agricultural Practices • Topsoil is the surface layer of soil, rich in organic matter . • Erosion is the movement of rock and soil by wind and water. Farming increases erosion. • Desertification is when land in dry areas becomes desert like.
Agricultural Practices • Adding organic matter to the soil is enriching it. • Compost, partially decomposed organic material, is added to soil to enrich it. • Salinization is the accumulation of salt in soil.
Agricultural Practices • In America, pests eat about 13% of crops. • Worldwide, pests destroy about 33% of crops. • Most use pesticides, chemicals used to kill pests.
Agricultural Practices • Pesticides are an effective way to kill pests and have been used heavily in the past. • Over time, they have shown to be harmful to plants, insects, wildlife and people. • Sometimes pests can develop a resistance and render the pesticide useless. • Many pesticides are persistent and can remain in the environment for a long time.
Agricultural Practices • Biological Pest Control is the use of living organisms to control pests. • Types include: • Pathogens • Selective breeding for resistance • Use chemical from plants • Use growth regulators • Use pheromones
Agricultural Practices • Integrated Pest Management is a modern method of controlling pests on crops. The goal is to reduce pest management to a level that causes minimal economic damage.
Agricultural Practices • Genetic engineering is the modification of genetic material to yield a better crop. Desirable traits are transferred between plants. • Although prevalent in the United States, Europe has stringent laws evaluating all gm crops that are sold.
Agricultural Practices • Sustainable agriculture is a new movement that conserves natural resources and helps keep the land productive indefinitely.
Animals and Agriculture • Animals require more resources than plants to harvest but have more protein and essential amino acids. • Most humans include some animal products in their diet. • A domesticated animal is bred and managed for animal use.
Animals and Agriculture • Many animals are overharvested. • Over 23% of all seafood is from aquaculture, the raising of aquatic organisms for human use.
Animals and Agriculture • Livestock are animals that are raised to be used on a farm or ranch or to be sold for profit. • Ruminants are cud chewing mammals that have three or four chambered stomachs. • Domesticated birds raised for meat and eggs are called poultry.
At the end of this chapter you should… • Understand the struggle of feeding the human population now and in the future. • Be able to compare modern and traditional agriculture. • Understand agricultural challenges with soil and how they are overcome. • Be able to discuss pests and the many types of control available. • Be able to define all of the bold terms in this presentation.