Agriculture and other resources 10-15% of AP questions Resource - A supply of something that can be drawn on as needed Tragedy of the commons – Garry Hardin.

Agriculture and other resources

10-15% of AP questions

Resource - A supply of something that can be drawn on as needed

Tragedy of the commons – Garry Hardin – 1950s

Dependent on population, areas of high population put strain on resources

“Food for China”

Conservation

Management and regulation of resources

Renewable vs. Nonrenewable

• Natural Resources – describe as resource, it has value (economic) - ecosystem capital

• Renewable resource – can be regenerated quickly, less likely to run out

• Non renewable resource – typically formed by slow process (geological), incapable of being regenerated during human existence

Food and the environment

• Food production impacts environment.

• 77% of food comes from agriculture, 16% comes from grazing lands, 7% from the ocean

In need of food..

Agriculture

• Farms are getting larger, employs 15% of workforce in US (mechanized, uses fossil fuels)

• Traditional Subsistence Agriculture – Produce enough food for family (42% of world’s population). Most use Slash and burn to build soil• Subsistence Crops –- used directly for food• Cash Crops – sold or traded for food

• Green Revolution – time after industrial revolution where farming has become mechanized and maximize crop yields

Fertilizers

• Native Americans planted fish with corn crops; manures and other organic materials used frequently

• Fertilizers increase nitrogen, phosphorous, and other limiting factors that may get depleted in soils

• Green Revolution relies on fertilizers

• Fertilizers not used, food production drops 40%

• Downside:• Energy to produce• Energy to transport• Dangerous pollutants – lead to eutrophication

Eutrophication (over enrichment)

Pesticides

• Green Revolution relies on Pesticides

• Decreases/Kills pests – insects, fungi, rodents, birds

• Harms environment - Biomagnifies in food chain

• Species become immune; new pesticides are needed

• 1947 – Federal Insecticide, Fungicide, and Rodenticide Act (FIRFA) – EPA approves all pesticides

Irrigation

• Green revolution relies on irrigation

• Dust Bowl – Ogallala Aquifer

• Excessive Irrigation leads to salt build up, farmers flood lands to move salt deeper.

GM Foods

• Green Revolution relies on GM foods

• Foods where the DNA is modified to produce different compounds that are resistant to pests/droughts – even some that work with certain fertilizers $$$

• Golden Rice – Has vitamin A and Iron

• Problem – pollen mixes with non GM foods – make hybrids – leads to evolution

• Problem #2 (maybe)– we evolved with foods, we did not evolve with modified foods.

MEGA GRAINS

• Rice, Wheat and Corn – half total calories consumed in the word

• GM has made plants that make more food biomass, rather than plant biomass

• Potatoes, sweet potatoes, manioc, sugarcane, sugar beets, beans, soybeans, barley, sorghum, coconuts, and bananas – provides most food (95%)

SOIL Degradation

• Soil breaks down – erosion occurs/nutrients deplete

• Soil Conservation Act of 1935 – made National Resource Conservation Service to educate farmers about techniques that reduce soil erosion/depletion:• Contour Plowing – rows planted across hillside• Terracing – flat platforms are level - prevent runoff• No – till methods – no plowing, reduced carbon loss• Crop rotation – crops are cycled to return nutrients, legumes

are usually planted, alfalfa, soybean…corn, other crops• Intercropping – bands of different crops, helps prevent erosion

• And I have noticed…farmers leave corn husks in over winter to reduce wind erosion on farms

ORGANIC??

• https://www.organicconsumers.org/organlink

• http://www.beyondpesticides.org/organicfood/health/

RANCHES

• Changes in agriculture have affected changes in livestock – more grazing land, more livestock

• Among of grazing animals cannot exceed the time it takes for grass to re-grow – overgrazing

• Overgrazing leads to erosion and soil compaction – solution: rotate grazing lands

• The Bureau of Land Management is responsible for designating and managing federal grazing land

• Another problem is waste products from cattle effecting water – leads to eutrophication

FROM BUREU OF LAND MANAGEMENT: YELLOW IS FEDERAL

GRAZING LAND

FORESTS AS A RESOURCE

• Number of trees growing in forest is the same at 100 years ago, but only 5% of forests are left – most of the trees have been replanted and are young

• Deforestation – removal of trees from , happening more in developing countries: made into farmland and pastures and being exported to developed countries

• Deforestation depletes the soil

• Deforestation of Tropical Rain Forests reduces biodiversity – some biodiversity not yet identified

Where are we gaining/losing forests?

FORESTS:

• Three types of forests:• Old Growth Forest – one that has never been cut,

contain incredible biodiversity• Second Growth Forests – areas where cutting has

occurred – this is a new younger forest• Plantations/Tree Farms – planted and managed;

usually harvested (Silviculture – management of plantations for harvesting)

• Methods of harvesting:• Clear-cutting – removal of all trees in an area• Selective Cutting – removal of selected trees in the

area

National Forest Policy

• Federal Government owns 35% of all land in US

• President Lincoln created first land grant at Yosemite national park.

• 1916 – National Park System was created – preserve forests and grasslands

• Federal Government passed laws to preserve public lands:• 1964 Wilderness Act – establish road free areas of

5,000 acres or more• 1968 – Wild and Scenic River Act – Protection of rivers

with scenic, recreational, fish and wildlife or others.

Natural Events that effect Forests

• Tree disease (“knots in trees) and pests (insects) – manage by removal of trees on purpose, pesticides, creating resistant trees

• Forest Fires• Surface Fires – burn underbrush and low trees,

leave mature trees – they can benefit the forest, recycle nutrients

• Crown Fires - high temperatures and burn most of forest, dangerous to wildlife

• Ground Fires – Can burn underground, difficult to detect and/or extinguish

Ocean Resources

• Fishery – Catching, processing, or selling fish

• 12-mile limit up to the 1960s – limited the national waters up to 12 miles off coast

• Expanded to 200 mile limit to be able to conserve national waters

• Capture fishing methods: caught in the wild

• By – catch: caught, but not the intended target – could be birds, mammals or other fish

• Fishing strategies that increase the by-catch:• Driftnets – floating nets that catch everything• Long lining – long lines that catch everything• Bottom trawling – ocean floor is scraped with large nets

AQUACULTURE

• Raising of farm fish, or bivalve etc… - raised in captivity

• Also called fish farming

• Problem – accidental release of farmed fish into wild, could reduce new genes/diseases into wild stock

Endangered aquatic ecosystems

• Most public outrage is about whales and dolphins – International Whaling Commission (1974) regulates international whaling – sets limits for Norway (food) and Japan (scientific use)

• Coral Reefs – made by Cnidarians in mutualistic relationship with algae, high water temperatures (kills algae) lead to coral bleaching. Somewhat normal with El Nino

Mangrove

• Coastal wetlands – where freshwater meets salt – water has a lot of nutrients from flowing freshwater, good for plants to grow

• Threatened by overfishing and changing of habitat

• Very delicate brackish water ideal for young life – becomes a breeding area, and hence a feeding area for wildlife

• Also plants help prevent erosion, and good to support coastline

El Nino?• Prolonged warming in Pacific Ocean in sea surface

temperatures – about .5 – 1 degree Celsius – happens every couple years (2 to 7 years, most commonly 5 years)

• Affects coral reefs, as well as developing countries that rely on aquaculture for food

Legislation to regulate Ocean resources

• 1965 – Anadromous fish act – protect fish that live in ocean/breed in fresh water (that is what anadromous means)

• 1976 Magnuson Fishery Conservation Act – Management of ocean fishing

• 1972 – Marin Mammal Protection Act – Conserve Marine Mammals

• 1973 – Endangered Species Act – Broad protection for species places on endangered or threatened list in US; either residing in US or outside US

• 1982 – UN Agreement for the implementation of the provisions of the UN convention of the law of the sea – set up provisions for international regulation of fish

• 1975 C.I.T.E.S - - agreement between different governments to ensure that trade of plants/animals toes not threaten species survival

Mining

• Metallic minerals – mined for metals, extracted during smelting (heat and chemicals are used to reduce ore)

• Nonmetallic – extracted from mineral state, in natural state

• Most environmental concerns, surround damage during the mining process• Strip Mining/Shaft Mining• Acid the leaches from water into environment• Needs a lot of energy to mine

Mining

• 1977 – Surface Mining Control and Reclamation Act – helps coal minds handle pollutants and abandoned mines

• 1972 – Mining Act – Governed mining minerals on public land

• 1920 – Mineral Leasing Act – Permitted Bureau of Land Management to make leases for land

• 1977 – Surface Mining Control and Reclamation Act – helps coal minds handle pollutants and abandoned mines

Economics oF Resources

• Cost – benefit analysis – weighing the potential profit with negative environmental impacts

• Marginal costs/benefits

• Externalities – consequences of using resources• Positives – more $$/jobs/etc…• Negatives – use of resources, resources

depleted