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Environment Tenth Edition

Raven

Chapter 18

Food Resources

Overview of Chapter 18

• World Food Security

• Food Production

• Challenges of Producing More Crops and Livestock

• Environmental Impacts of Agriculture

• Solutions to Agricultural Problems

• Fisheries of the World

Urban Agriculture

• Increases food availability for urban communities

• Does not require large swaths of land

• Ex: Rooftop gardens o Helps clean water, reduce

flooding/runoff

o Work experience

o Connects city residents to where food comes from

World Food Security • 842 million people lack

access to food for healthy, productive life

• Feeding the growing population is difficult

• Annual grain production (right) has increased from 1961–2008

o Due to increase in population, amount of grain per person has not increased

Food Security and Overeating

• Food security - goal of all people having access to sufficient, safe, nutritious food at all times

• 182 million children under age 5 are underweight worldwide o Malnourished – not receiving specific essential nutrients

• Overeating on poor nutritional food becoming widespread problem

• Nutrition transition in developing nations o Emergence of overeating in countries that also have

widespread hunger

Famines

• Temporary, but severe shortage of food

• Occurs usually when natural event, such as drought or flood, is accompanied by political instability

• Developing nations of Africa, Asia, and Latin America are most at risk

• More people die from endemic malnutrition rather than starvation during a famine

Maintaining Grain Stocks

• Grain stocks provide measure of food security

• Amounts of rice, wheat, corn, and other grains remaining from previous harvest

• All time highs in mid-1980s and late-1990s

o 86 days’ supply (2016)

• Fluctuations in supply, food prices, and political instability can result in food riots

Decline in Grain Stocks

• Environmental conditions affect stocks o Rising temps

o Falling water tables and droughts

• Competition for produced food o Ex: corn used for ethanol production rather than food

(green energy demand)

• Food choices o Grain goes toward feeding livestock

o Increased meat consumption in developing countries calls for more feed

Economics, Politics, and Food Security

• Leading cause of famine is type of government o Cost money to store, produce, transport, and distribute

food

o Getting food to those who need it is political

o Observation by Amartya Sen (Nobel Prize 1998)

• Globalization – process of people increasingly linked through economics, communication, transportation, governance, culture

• Governments may focus on producing food for exports rather than food for population

Food Insecurity

• Enough food is produced, but not shared equally

• Food insecurity - state of fear of not being able to acquire sufficient food o 1.3 billion people are so poor they cannot afford proper

nutrition

• Women particularly useful in food production o Some regions, women grow 80% of basic nutritional

foods

o With increase in women’s wages, money goes toward food

Undernourished People

• Chronic hunger more common in: o Rural than urban areas

o Infants, children, and the elderly

• Most in Asia

• Highest proportion of population in Sub- Saharan Africa

Food Sources (1 of 2)

• Few species provide majority of our food o Large variety does

exist, but few used

• 3 cereal grains provide 50% of all calories

o Disease or other factor in these crops could cause massive food shortages

Table 18.1 The 15 Most Important Food Crops In Terms Of Production

Plant Crop Type of Crop

2012 World Production* (1000 tons)

Sugar cane Sugar plant (stem) 2,020,031

Corn (maize) Cereal grain 961,289

Rice, paddy Cereal grain 793,376

Wheat Cereal grain 739,513

Potatoes Ground crop (tuber) 402,133

Sugar beet Sugar plant (root) 297,476

Cassava Ground crop (root) 289,451

Soybeans Legume 266,585

Food Sources (2 of 2)

Plant Crop Type of Crop 2012 World Production* (1000 tons)

Tomatoes Fruit (annual herb) 178,347

Barley Cereal grain 146,482

Watermelons Fruit (vine) 116,153

Sweet potatoes Ground crop (root) 113,698

Bananas Fruit (tree) 112,428

Onions, dry Ground crop (root) 91,328

Apples Fruit (tree) 84,193

*Based on the 20 highest-producing countries for a specific agricultural commodity.

Source: World production data from FAO.

Meat Consumption

• Constitute 40% of the calories consumed in developed countries

• 5% of calories consumed in developing countries

• Livestock inefficient converter of plant food o For every 100 calories

of food cow consumes, 86 burned off

Principle Types of Agriculture

• Industrialized agriculture o Modern agricultural methods, which require a large

capital input and less land and labor than traditional methods

o Also called high input agriculture

• Subsistence Agriculture o Traditional agricultural methods, which depend on labor

to produce enough food to feed oneself and one’s family

o Shifting cultivation, slash and burn agriculture, nomadic herding, intercropping

Energy Inputs in Industrialized Agriculture

Subsistence Agriculture

• Renewing interest in subsistence or growing a lot of your own food

• Polyculture o Type of intercropping that

grows plants together each maturing at different times

o Ex: three sisters (corn, beans, and squash)

Decline in Plant and Animal Variety and Diversity

• Industrialized agriculture has created more uniformity (domestication)

• Domestication decreases genetic diversity o Farmer selects and propagates animals with

desirable agricultural characteristics

o Process of taming animals or adapting wild plants to serve humans markedly altering characteristics of the organisms

• Genetic diversity is the variation of traits in a population’s genes that can be inherited

Scientific Advances Have Increased Yields • Increasing yield mostly in

developed nations

• Greater knowledge and use of: o Pesticides

o Selective breeding

• Green Revolution o 1960s transition of food

production toward higher-yielding varieties

Average U.S. wheat yields, 1950-2010

Grow Appalachia

• Mountains in this area are primarily forested

• Fossil fuel dependent economy

• Big gap between wealthy and poor

• Grow Appalachia Project in 2009 to address food insecurity through large- scale gardening and small farm investment

Supplements for Livestock

• Hormones increase animal growth rates o Regulate bodily functions and foster growth

• U.S. and Canada, banned in Europe (due to health concerns)

o Antibiotics • 40% of antibiotics produced in U.S. used in livestock

operations

• Problems with increased bacterial resistance- some bacteria are resistant to every antibiotic known

Evolution of Antibiotic 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

• Used to produce Genetically Modified (GM) food o Ex: golden rice - rich in beta carotene (prevent Vitamin A

deficiency in developing countries)

o Plants that are tolerant to insect pests, heat, cold, drought, or acidic soils

o More productive farm animals

The Genetic Engineering Process

GM Foods in the U.S.

• 50% of GM foods planted in U.S.

• Proportion of crops planted has increased since first introduced

Backlash Against GM Foods • Determined safe for human

consumption

• Concerns about GM seed or pollen spreading in wild o Currently does not appear to be an

issue

o Long term unknown

• European Union has approved only one GM crop (2014)

• Cartagena Protocol on Biosafety lessens the threat of gene transfer from GM organisms to wild relatives by requiring appropriate handling procedures

Environmental Effects of Industrialized Agriculture

Agricultural Effects to Land

• Land degradation reduces potential productivity o Natural or human-induced process that decreases the

future ability of the land to support crops or livestock

• Clearing grasslands and forests for farms results in habitat fragmentation o Breakup of large areas of habitat into small, isolated

patches

Some Goals of Sustainable Agriculture

• Agricultural methods that maintain soil productivity and a healthy ecological balance while having minimal long-term impacts

Sustainable Agriculture

• Examples: o Natural Predator-prey relationships instead of pesticides

o Crop selection, rotation, and conservation tillage

o Supplying nitrogen to soil with legumes

o Organic agriculture

• Integrated Pest Management (IPM) o Limited use of pesticides along with sustainable

agricultural practices

• Rise of a second green revolution focused on long-term sustainability?

Problems of World Fisheries Fish provides highly nutritious protein (15% of human protein from fish and seafood)

• No nation can claim open ocean o Resource susceptible to overuse

and degradation

• Overharvesting - Many species severely depleted o Declines of 90% of large

predatory fish

o 30% of world’s fish stock are overexploited

Modern Commercial Fishing Methods

• Overharvesting results from: o Sophisticated fishing

equipment

o Bycatch killed off

• Magnuson Fisheries Conservation Act (1977)

Aquaculture

• Growing of aquatic organisms for human consumption o Great potential to supply food,

huge industry

o Location may hurt natural habitats (wastes, built in natural habitats)

o Fish grown on antibiotics may escape and interbreed with wild populations

• Mariculture – cultivation of marine organisms

Aquaculture Can Decrease Sensitive Habitats • Shrimp farm in coastal mangrove forest

• Shrimp aquaculture single largest factor for mangrove habitat loss

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