Chapter 19 Food Resources: A Challenge For Agriculture

Overview of Chapter 19 Food and Nutrition World Food Problems Principle Types of Agriculture Challenges of Producing More Crops and Livestock Environmental Impact of Agriculture Solutions to Agricultural Problems Fisheries of the World

Food and Nutrition Carbohydrates Sugars and starches metabolized by cellular respiration to produce energy Proteins Large, complex molecules composed of amino acids that perform critical roles in body Lipids Include fats and oils and are metabolized by cellular respiration to produce energy Vitamins and Minerals Inorganic elements such as zinc & iron Vitamins are complex molecules need in small amounts

Human Foods

World Food Problems Feeding growing population is difficult Annual grain production (left) has increased since 1970 Grain per person has not (right)

Food Insecurity Regions in the world with greatest food insecurity are South Asia and Sub-Saharan Africa low income = food deficits in countries Problem is not producing enough food but distribution and intermittent problems such as famine and politics. 1. Undernourished – fewer calories than needed 2. Mal-nourished – getting food, but not enough specific essential nutrients (e.g. protein) 3. Over nourished – eat in excess of required for general nutrition 4. Famine – severe food shortage

2 Diseases of Malnutrition Kwashiorkor- resulting from protein deficiency (big stomach) Marasmus- emaciation from a diet low in calories and protein

World Food Problems Famine Failure of crops caused by drought, flood or catastrophic event Temporary but severe shortage of food Maintaining World Grain Carryover Stockpiles Amounts of rice, wheat, corn and other grains remaining from previous harvest Provides measure of food security Decreased each year since 1987 UN feels carryover stock should not fall below 70 days

World Grain Carryover Stock Why the decline? Rising temperatures Falling water tables and droughts Ethanol production More grain is going towards feeding livestock Animal products are 40% of diet in developed counties. 5% in developing

World Food Problems Poverty and Food 1.3 billion people are so poor they cannot afford proper nutrition More common in Rural than urban areas Infants, children and the elderly Economics and Politics Cost money to store, produce, transport and distribute food Getting food to those who need it is political Cultural Acceptance – what is food for one culture is not for another

Types of Diets Omnivores – eat both animals and plants Vegetarians 1. Lacto ovo – milk, eggs and food from milk 2. Lacto-vegetarians – no eggs, milk and milk products ok 3. Vegans – no milk, eggs or their products

Principle Types of Agriculture Industrialized agriculture Modern agriculture methods that require large capital input, and less land and labor

Principle Types of Agriculture Subsistence Agriculture Traditional agricultural methods, which are dependent on labor and large amounts of land Examples: Shifting cultivation Slash and burn agriculture- clearing small patches of tropical rain forests to plant crops Nomadic herding – livestock on land to arid for crops. Herds moved to find grazing Intercropping

Challenges of Producing More Crop and Livestock Domestication and Genetic Diversity Domestication of crops and livestock causes a loss of genetic diversity Farmer selects and propagates animals with desirable agricultural characteristics Many high yielding crops are genetically uniform High likelihood that bacteria, fungi, viruses, etc. will attack and destroy entire crop

Challenges of Producing More Crop and Livestock Increasing Crop Yield Food production increased in developed countries (wheat (left) Pesticides Selective breeding

Green Revolution High Yielding Rice Varieties Production of more food per acre of cropland using modern methods and new high yielding varieties High Yielding Rice Varieties

Food Additives Sugar & salt are the 2 most common food additives Common preservatives- sodium propionate & potassium sorbate Other food additives- anti oxidants, nitrates/nitrites Food & Drug Administration- responsible for monitoring food additives

Food Processing Manual alteration via drying, canning, freezing, irradiation, curing & refrigeration Food additives to enhance taste & color or texture, improve nutrition, reduce spoilage &/or extend self life

Challenges of Producing More Crop and Livestock Increasing Livestock Yields Hormone supplements US and Canada do this Europe does not citing human health concerns Antibiotics 40% of antibiotics produced in US are used in livestock operations Problems with increased bacteria resistance

Antibiotic Use and Resistance

Genetic Engineering Manipulation of genes by taking specific gene from a cell of one species and placing it into the cell of an unrelated species

Issue with Genetically Modified Organisms (GMOs) Determined to be safe for human consumption Concerns about GMO seed or pollen spreading in wild Backlash against GMOs GMOs are not currently labeled FDA finds it would be counterproductive and expensive to label

Environmental Impacts of Agriculture High use of fossil fuels and pesticides Air pollution Untreated animal wastes and agricultural chemicals Water pollution Harms fisheries Insects, weeds, and disease-causing organisms developing resistance to pesticides Contaminate food supply

Environmental Impact of Agriculture Land degradation Decreases future ability of land to support crops or livestock Habitat fragmentation Breakup of large areas of habitat into small, isolated patches Cultivating marginal lands Irrigating dry land Cultivating land prone to erosion

Solutions to Agricultural Problems- Sustainable Agriculture

Sustainable Agriculture Examples: Natural Predator-prey relationships instead of pesticides Crop selection Crop rotation and conservation tillage Supplying nitrogen with legumes Organic agriculture Integrated Pest Management (IPM) Limited use of pesticides with sustainable agriculture practices

Fisheries of the World- Problems No nation lays claim to open ocean Resource susceptible to overuse and degradation Overharvesting Many species are at point of severe depletion Cod (right) 62% of world’s fish stock are in need of management action

Fish/Aqua culture Fish/Seafood popular cause they are a source of high quality protein (5% of human diet is seafood) 4 Main categories 1. Fish 2. Crustaceans 3. Mollusks 4. Algae

Fisheries of the World- Problems Overharvesting (continued) Sophisticated fishing equipment Bycatch killed off Magnuson Fisheries Conservation Act

Magnuson Fishery Conservation Act Regulates U. S. Fishing Established 8 regional fishery management councils. Magnuson-Stevens Fishery Conservation and Management Act. Requires regional councils and National Marin Fisheries Service

Fisheries of the World- Problems Ocean Pollution - dumping ground Oil Heavy metals Deliberate litter dumping Stormwater runoff from cities and agricultural areas Aquaculture (mariculture) Growing of aquatic organisms for human consumption Great potential to supply food

Fisheries of the World- Problems Aquaculture (continued) Locations of fisheries may hurt natural habitats. Potential for release of invasive exotics Produce waste that pollutes adjacent water