Feeding the World

Global Undernutrition

As many as 24,000 people starve to death each year

Undernutrition- not consuming enough calories to be healthy.

Malnourished- a persons diet lacks the correct balance of proteins, carbohydrates, vitamins, and minerals even though they get enough calories.

Overnutrition- too many calories and improper foods that causes a person to become overweight.

Nutritional Requirements

Food Security- condition where people have access to sufficient, safe and nutritious food

Famine- a condition in which food insecurity is so extreme that large numbers of deaths occur in a certain region over a relatively short period of time.

Anemia- iron deficiency (most widespread nutritional deficiency)

Annual Meat Consumption

Grains including corn, rice, wheat and rye make up the largest component of the human diet.

Corn, rice & wheat make up 60% of human energy intake

Meat is the second largest component

Fish is the third

As income increases, people add more meat to their diet.

Poverty- unequal food distribution

Political and economic factors

Agricultural resources being diverted to feed livestock and poultry rather than people-results in low energy transfer

Reasons for Undernutrition and Malnutrition

More land required for agricultural production

Improve crop yields

Reduce consumption of meat

Harvest more from the world’s fisheries

Conventional agriculture- industrial agriculture where labor is reduced and machinery is used.

Traditional farming- still used in the developing world where human labor is used and not machinery.

Shifting agriculture- used in areas with nutrient poor soils. It involves planting an area for a few years until the land is depleted of nutrients and then moving to another area and repeating the process. (“Slash and Burn: within the tropical rainforest)

Nomatic grazing- moving herds of animals to find productive feeding grounds.

Farming Methods

New management techniques and mechanization as well as the triad of fertilization, irrigation, and improved crop varieties. This has increased food production dramatically.

Energy Subsidies- the energy input per calorie of food.

Greater for modern agriculture than for traditional agriculture.

Fossil Fuel Energy is the primary energy subsidy for large-scale food production.

The Green Revolution

Depletion of ground water- for example the Ogallala Aquifer

Waterlogging- when the soil remains under water for prolonged periods which impairs root growth because the roots cannot get oxygen.

Salinization- when the small amounts of salts in irrigation water become highly concentrated on the soil surface through evaporation.

Irrigation Problems

Organic fertilizers- organic matter from plants and animals. Typically made from animal manure that has been allowed to decompose.

Inorganic fertilizers (synthetic)- fertilizers that are produced commercially. This is usually done by combusting natural gas, which allows nitrogen from the atmosphere to be fixed and captured in fertilizer.

Fertilizers

Pros-

Increased Crop Yields

Easy application

Targeted toward specific crop needs

Enables us to feed the world

Cons-

Manufacturing requires fossil fuels

Runoff leads to eutrophication and hypoxia in adjacent waterways

Does not add organic matter to the soil

Growing a large amount of a single species of plant.

Monocropping

Pros-

Improves agricultural productivity

Allows large expanses of land to be planted, fertilized, treated with pesticides and then harvested

Cons-

Leads to soil erosion

More vulnerable to attack by pests

Loss of diversity

Over-use and depletion of soil

Pesticide- a substance that kills or controls organisms that people consider pests.

Insecticide- target insects

Herbicides- target plants

Pesticides

Broad-spectrum pesticides- designed to kill many different types of pests.

Selective pesticides- designed to kill a narrower range of organisms.

Pesticides

Persistent- pesticides that remain in the environment a long time.

Nonpersistent- pesticide that breaks down relatively rapidly, usually in weeks to months.

Pesticides

Bioaccumulation- some pesticides are found to build up over time in the fatty tissues of predators.

An example was DDT.

When an organism containing the pesticide is eaten, the chemical is transferred to the consumer.

This eventually leads to very high pesticide concentrations at high trophic levels.

Pesticides

Resistance- pest populations may evolve resistance to a pesticide over time. These are said to be resistant.

Pesticide treadmill- the cycle of pesticide development followed by pest resistance, followed by development of a new pesticide.

Pesticides

Desertification- When soil is degraded by agriculture to the point at which they are not longer productive.

Desertification

CAFOs (concentrated animal feeding operations)- large structures where animals are being raised in high density numbers.

High-Density Animal Farming

Pros-

Minimizes land costs

Improves feeding efficiency

Lowers the costs of meats

Cons-

Antibiotics given to animals to reduce disease is leading to antibiotic-resistant strains of bacteria

Waste

Unethical treatment of animals

Fishery- a commercially harvestable population of fish within a particular ecological region.

Fishery collapse- the decline of a fish population by 90% or more.

Bycatch- unintentional catch of non-target species.

Harvesting of Fish and Shellfish

Aquaculture- the farming of aquatic organisms such as fish, shellfish, and seaweeds.

Aquaculture

Pros-

Can alleviate some of the human-caused over fishing

Provide protein for undernourished people

Potential to boost economies in developing countries

Cons-

Waste water (pollution) can be pumped back into water systems

Fish may escape and breed with wild species or out-compete them

Sustainable agriculture- producing enough food to feed the world’s population without destroying the land, polluting the environment, or reducing biodiversity.

Intercropping- two or more crop species are planted in the same field at the same time.

Crop rotation- rotating crops species from season to season.

Agroforestry- intercropping trees with vegetables.

Contour plowing- plowing and harvesting parallel to the land to prevent erosion.

Sustainable Agriculture

No-till agriculture- helps to stop soil degradation by leaving crop residues in the fields and not tilling the land after each harvest.

No-till Agriculture

Greater yield

Greater food quality

Resistant to harsh conditions such as drought

Engineered plants with essential vitamins

Reductions in pesticide use

Reduction of world hunger by increased food production

Salmon engineered to grow to its full size in half the time

Increased profits

Benefits of Genetic Engineering

Safety for human consumption

Allergic reactions

Effects on biodiversity

Seeds don’t stay put!- breeding with wild relatives may eliminate wild species

Regulation of genetically modified organisms

Not mandated that items be labels

Organic food excludes GMOs but cannot be guaranteed

Concerns about Genetically Modified Organisms

Integrated pest management- using a variety of techniques designed to minimize pesticide inputs.

Crop rotation

Intercropping

Planting pest resistant crop varieties

Creating habitats for predators

Limited use of pesticides

Integrated Pest Management

Organic agriculture- production of crops without the use of synthetic pesticides or fertilizers.

Organic Agriculture