Food Resources Chapter 13 Were not in Kansas

Food Resources Chapter 13

We’re not in Kansas anymore ¬New technology for Kansas Prairies ¬Polyculture – Plant perennial grasses – Legumes (return nitrogen to the soil) – Sunflowers – Grain crops – Plants that provide natural pesticide

This makes Toto very happy ¬Perennial polyculture blended with monoculture helps in the following way ¬Less plowing – lower soil erosion ¬Less pollution from pesticide use/fertilizer ¬Less need for irrigation (deep root systems)

How is the world fed? ¬ Cropland (produce grain mostly) ¬ Rangeland (livestock) ¬ Oceanic fisheries ¬ Food production has increased to keep up with the growing population ¬ Machines, inorganic fertilizers, irrigation, pesticides, high-yield varieties of wheat/rice, increased density in feedlots, aquaculture

What are the implications of increased food production ¬Environmental degradation – Soil loss, lost habitat, contaminated water ¬Pollution – nitrogen, phosphates, pesticides ¬Lack of water – diminishing water table ¬Overgrazing – reducing grassland productivity ¬Overfishing – reducing fish stocks (? ) ¬Loss of ecological services

What do we really eat ¬ (other than Mc. Donalds, of course) ¬ 15 plants and 8 animals make up 90% of the food we consume ¬ Big 3 grains – wheat, rice, corn ¬ Big 3 meats – beef, pork, chicken ¬ Fish – important food source for more than a billion people ¬ What, no tofurkey?

Types of Agriculture ¬Industrialized or high input – Uses high amounts of: – fossil fuel energy – Water – Commercial inorganic fertilizer – Pesticide use – monocultures

Types of Ag continued ¬Plantation Agriculture (a variety of industrial) – In tropical areas – Growing cash crops (tobacco, coffee, sugarcane, cocoa, bananas, soybeans)

Types of Ag continued ¬Traditional Subsistence Ag – Uses mostly human and animal labor – Low use of inorganic fertilizer – Low pesticide use – Usually food for family only, small surplus – Includes shifting cultivation in tropical areas and nomadic livestock

Types of Ag continued ¬Traditional Intensive Ag – High labor – High fertilizer/pesticide use – High yield (able to sell for profit) – Typical of rice production

Green Revolution ¬ High input monocultures to the rescue? ¬ Three steps – Developing high yield monocultures – Using large inputs of fertilizer/pesticide/water – Increase the frequency and density of farming First green revolution –US and Europe Second green revolution – Tropical areas especially rice in Asia

The US and Food ¬ With only 0. 3% of the farm labor force, the US produces 17% of the worlds grain ¬ US spends only about 10 -12% of their income on food (18% Japan, 40 -70% developing countries) ¬ In the US it takes 10 units of fossil fuel to produce 1 unit of food ( as compared to intensive which takes 1 unit to produce 10)

Growing Techniques ¬ Monoculture – only one plant type ¬ Interplanting – several monocultures on one plot of land (including) – Polyvarietal cultivation – several varieties of the same plant – Intercropping – two or more plant types grown at the same time – Alley cropping – plants and trees together – Polyculture – several types of plants on one plot at one time harvested at different times usually

Increase in food production ¬Since 1950 grain production has tripled ¬Average food price dropped 25% ¬Food traded worldwide quadrupled ¬Meat production has risen for 41 years

Problems with production ¬Areas with 2 billion (sub-Saharan Africa) growth is surpassing food production ¬Grain production has leveled off – Limits to irrigation, fertilizer, pesticide – Loss of topsoil, agricultural land, and salinization of the soil

Nutrition ¬ Nutrition affects life expectancy, disease resilience, and life quality ¬ Undernutrition – do not get enough food ¬ Malnutrition – do not get enough key nutrients (vitamins and minerals) ¬ WHO says that 10 million die annually (most under 5) from poor nutrition and diseases associated with it

Effects of Food Production ¬Biodiversity loss – clearing land, pesticide runoff, lack of predators ¬Soil degradation- erosion, loss of fertility, salinization, desertification ¬Air pollution- fossil fuel emissions, dust ¬Water- sediment, fertilizers, pesticides, aquifer depletion, increased runoff ¬Human Health- nitrates in water, pesticides, bacterial contamination of meat

GMO ¬Genetically Modified Organisms ¬Faster than crossbreeding, less costly, unlimited combination ¬Nearly 2/3 of US food in supermarkets contains GMO’s ¬Do not know all the long term effects on the environment

Meat Production ¬Rangeland – 40% of the planet’s ice free land, mostly grasslands ¬Pasture – managed grasslands and meadows, often irrigated, normally fenced ¬Rangeland plants- anchor soil, extract deep water (survive drought), store nutrients ¬Most grasses can have the top eaten and grow back easily

Problems with meat production ¬Concentrated production facilities – Foul odor, water pollution (wastes) (+ aquifer) ¬Overgrazing – Lower productivity of grasses – Reduces plant cover (soil erosion wind/water) – Compacts soil – Increase amount of woody shrubs – Major cause of desertification

Pesticide and pest control

Do you know What are the problems with pesticide? What are the different types of pesticide? When should pesticides be used? How are pesticides part of a negative feedback loop?

Pesticide problems Kills many other organisms Only about 2% reaches target species Kills genetically weak species, strengthening the species overall Often the toxin has a long life span Creates birth defects Kills natural predators

Types of pesticide Herbicides – weed killers Fungicides – fungus killers Nematocides – worm killers Rodenticides – rat and mouse killers DDT – first of the second generation pesticides and world’s most used pesticide in 1948. In the US most pesticide is used on corn and cotton (90% of insecticide and 80% herbicide)

Pros for pesticide Human lives are saved by killing disease carrying pests (mosquitoes) Increased food supply Increased profit for farmers Pesticides work quickly to remove pests When used appropriately the health risk to humans is low compared to the benefit (ACSH)

Pesticide info Insecticide Chlorinated hydrocarbons – DDT, aldrin, diedrin, chlordane, toxaphene, mirex These are the bad ones Long lasting Biologically magnified

Pesticide info continued Most other types of pesticide are relatively safe – low persistence (up to a few weeks) and are not biologically magnified Organophosphates – malathion, DDVP Carbamates – aldicarb Botanicals – extracted from plants Micro botanicals – fungi, bacteria, protozoa Synthetics – “lasso, ” “roundup”

Bad types continued Fumigants are generally bad. Not only do they last a long time, and biomagnify, they often are spread vast distances with the wind Carbon tetrachloride Ethylene dibromide Methyl bromide

Positive feedback loop Pesticides increase genetic resistance making bugs stronger each generation Natural predators are also killed New pest populations can explode when predators are killed Leads to pesticide treadmill – having to use more and more pesticide to kill the pests because of the feedback loop

First pesticide awareness Rachel Carson – Silent Spring, opened the publics’ eyes to the danger of pesticide. Linked birth defect rise in population back to pesticide use.

The real problems Pesticides linger in the air and on foods Workers are exposed to high levels Animals are exposed to toxins while pregnant Tolerance levels are not set based upon health concerns, but upon crop concerns There is little enforcement of use of pesticides