Environmental Science Section 3 Part 2

For most of human histroy, how did humans subsisted?

By hunting and gathering

When did agriculture and domestication develop?

Roughly 12000 years ago

Why was the creation of agriculture considered a good and a bad thing?

Because 1. It allowed us to move beyond mere subsistence but it also caused exponential growth and also led to the degradation of the environment

What do some people say is the most harmful human endeavor in terms of the environment?

Agriculture

Where did Agriculture develop simultaneously

1. Fertile Crescent (Middle East),

2. China,

3. Mesoamerica (southern North and Central Americas),

4. Southeast Asia,

5. Africa and

6. lowland South America.

Traditional agriculture methods (3)

1. normal agriculture in nutrient rich places like the floodplain along the Mekong River in SE Asia.

2. Nomadic herding in semi-arid places like the Serengetti ecosystem in Tanzania, because intensive use of the soil would lead to desertification

3. Slash and burn agriculture in places where most of the nutrients are in vegetation such as rainforests of Central and South America. (Europeans, now in Amazon Basin and Central America). The ash acts as fertilizer, but it can be washed away by rain very easily, and it can also contribute to air pollution, can be used for subsistence but not commercial. The farmers often have to move around plots.

4. Intercropping/ crop rotations in Kenya, India or Thailand + using animal waste as fertilizer.

Burnt ash from trees/wood is rich in what?

Ca, Mg, K

What crop requires a great deal of nitrogen, and what crop is a nitrogen fixer?

corn, peas

What is being revived in organic agriculture in US and Europe?

Organic agriculture: traditional practices such as crop rotations, intercropping, etc.

Describe the start of the Green Revoltuion?

In the 1940s a US crop scientists Noman Borlaug created disease-resistant crops by crossing Mexican wheat with a Japanese dwarf variety. This, coupled with irrigation and fertilization, led to a lot of wheat, so much that Mexico became an exporter.

In 1970, Norman Borlaug received teh Nobel Peace Prize

Continuance of the Green Revolution

After Mexico, in Phillipines, a similar project was developed with rice, and from the 1950s through the 1970s, many countries also developed their own practices: combining better varieties of domestic animals and crops with intensive use of synthetic fertilizers, management techniques and machinery to increase food production rates

Between when and when did food production increase by how much?

Between the mid-1960s and the mid-1980s, food production increased by a factor of 2

By when were there how many centers promoting the Green Revolution?

By the 1990s, thee were at least 18 centers

How many farms were there in1960, and how many today?

4 million, half now

Downsides of the Green Revolution

1. It decreases the variety of crops

2. The production of synthetic fertilizers is a major source of water pollution (non-source) and the use of fossil fuel

3. It only benefits large scale commecial farms and excludes small farms

How much of the world is classified as agricultural land?

5 billion hectares (50 million km2) or 38% of the surface area of the earth

Land used for agriculture has decreased since when

1950

How much of agricultural land is livestock and how much is food

1/3 is food, 2/3 is grazing for livestock

What limitations of food production are we facing

limitations of arable land and water, because Green Revolution's benefits have been largely realized

Currently, how many species provide how much of the human diet?

30 provide 95%

6 provide 80%:

1. Wheat

2. Rice

3. Corn

4. Potatoes

5. Sweet potatoes

6. Manioc

Besides the 6 crops, what other crops are important to the diet?

1. Sugarcane

2. Sugarbeet

3. Beans

4. Soybeans

5. Barley

6. Sorghum

7. Coconut

8. Bananas

What are the grass crops?

1. Wheat

2. Rice

3. Corn

4. Barley

5. Rye

6. Oats

What are the fruits of the grasses called?

Cereals

What do cereals contain?

Carbs, protein, oils, vitamins, minerals.

Potatoes are

tubers

The type of crop grown in a country depends on the country's

temperature, moisture, sunlight,

The WHO estimates how many people lack access to adequate food

828 millionn people in the world

How many calories does an average person need and what deficit lead to bad functioning?

2200 kilocalories, deficit of 100-400 kilocalories

How much do we have to scale food production for 2050?

60%, according to the UN

How many people starve to death everyday?>

24000

Half of the grain in the world goes to feeding whom?

Livestock

In the US, what are fed to animals?

Corn and Soybeans

People in the US eat how much meat?

270 pounds or 123 kg of meat peryear

What plant mentioned is rich in protein?

Legumes

Grain multiplier for beef and chicken

7 and 2.7

What is the bright side about plowing and tilling

Aerate the soil, and loosen it.

light tilling alos allows a farmer to bury weeds

What is bad about plowing and tilling.

Large businesses usually uses tilling in a way that uncovers soil for a period of time, leaving it susceptible to erosion.

How much of soil is lost to erosion?

16%

What is compaction?

Use of heavy machinery compacts (tightens) the soil and counteracts the benefits of tilling/plowing

What has the greatest consequences of all agricultural practices?

Plowing.

What is SOC

Amount of organic carbon in soil

When do SOC build up?

SOC builds up again if a field is left alone.

How much of agricultural soil is impacted by what?

40% by erosion, compaction, waterlogging and salination

Example of irrigation reversing desertification

In the Imperial Valley of SE CA, 1 million acres of former desert become a source of fruits and vegetables, particularly in winter.

What does a 2016 report say about irrigation?

That only 20% of arable land is irrigated, but this 20% produces 40% of all food

Monocropping in Kenya

Good farmland in central Kenya for tea and new land in west Kenya for wheat

What is an example of a potato pest?

Colorado potato beetle.

What is the main advantage and disadvantage of monocropping?

It is economy of scale but it leads to less biodiversity and the resulting vulnerability to pests and diseases.

How are chemical fertilizers made?

Either through combustion in the air that fixes nitrogen or by breaking apart rocks with yummies

What elements are usually in fertilizers?

Nitrogen, Phosphorus and Potassium

What is the difference between natural humus and chemical fertilizer?

The speed at which they release nutrients and contribution to soil formation

Increase in chemical fertilizer from 1960 to 2020

From 20 miillion tons to over 200 million tons

What are the negatives of chemical fertilizers

1. It creates too much nutrient runoff as plants cannot take all the nutrients at once, and they leach

2. Fossil Fuels

What are the pesticides used by agribusinesses usually made from?

Petroleum: petrochemicals

What is an example of a broad-spectrum herbicide?

Roundup/glyphosate

In 2020, pesticide stats for US and Brazil

US: 400 thousand tons (most), Brazil: 375 thousand tons

300 million lbs of herbicide and 74 million lbs of insecticide

How many US agricultural workers (not farmers) and how many have pesticide poisoning?

3.8 million, 20k

How many animals are annually farmed in the US

10 billion, 9 billion are chickens

How do farmers create high-density feedlot farming?

Through the use of antibiotics and nutritional supplements,

What are the negative consequences of feedlot farming

1. Accumulation of waste is disposed of without caution. Eg. sometimes they are stored in Lagoons near the area, which can contaminate nearby waterways when raining.(Chicken waste in Maryland --> Chesapeake Bay)

2. Antibiotics are transferred to humans, leading to antibiotic-resistant bacteria in humans.

how much pollution has feedlot farming caused, according to the EPA?

35000 miles of rivers in 22 states and contaminated groundwater in 17 states

What are popular images of GMOs?

Frankenfoods, square tomatoes, animals that glow in the dark

Which chapter did Darwin mention artificial selection?

The very first chapter

Since when do GMOs exist and why?

10,000 through artificial selection

Artifically selected dogs

poodle and golden retriever

Describe some artificially selected GMO vegetables?

Cabbage, Brocolli, Collards

Difference between artificial selection and modern GMO

Artificial usually breeds between species within a kingdom or within a species to acquire traits. GMOs do this with non-related species

Plum and Apricot are members of what genus? What hybrid do they product

The genus prunus, plumcot and pluot

What is corn subject to attacks from?

1. Bollworm

2. European corn borer

What bacterium repels Bollworm and corn bearer?

The bacteria Bacillus thuringiensis (Bt)

How much of all corn in the US by 2002 is Bt

34% (all is fed to livestock)

What plants use Roundup Ready gene?

Corn, Soybean, and cotton plants

Monarch butterfly

Dies from the Bt corn pollen. concerns that the pollen can spread to milkweed plants, which are the Monarch butterfly's usual food. However, studies have shown little effect on caterpillars.

What is another fear about GMOs concerning its interaction with wild-type plants?

That the added genes will transfer to the natural plants through interbreeding, leading to the plantation of buffer zones, which are not effective because pollen is with wind. The only way is to make the GMOs sterile.

GMOs in commercal in 2002 and 2020

34% of corn

75% of soybeans

71% of cotton

90% for all in 2020

What does "sustainable agriculture" emphasize?

conservation and buildup of soil, integrated pest management, combine economic with environmnetal

What practices is sustainable farming similar to?

Trditional

Sustainable farming techniques

1. Intercropping

2. Agroforestry (East Afreica)

3. Contour plowing

4. Winter wheat so soil is not uncovered

5. Perennial Crops that do not have to be replanted every year

What does sustainable methods improve?

The ability of the soil to retain carbon.

What journal made it to CNN when and what did it say?

The journal Nature made the headlines in May 2003, saying many of the world's fish species are in danger of extinction,

Analysis of number of predatory ocean fish like swordfish and tuna caught in 13 fisheries, a dramatic decline over 50 years despite increases in tech and fishing efforts.

The first major study quantifying the decline for multiple fisheries across the globe.

Large scale fishing 50-60 years ago

Low yield methods using dories / schooners and baited hooks in Grand Banks off Newfoundland, Canada

Factory fishing ships these days can stay out at sea for ___ at a time

months, by processing and freezing their harvest

What is groundfish?

Fish that feed and are caught near the ocean floor

How are groundfish and shellfish caught?

By dredging with weighted trawler nets

Many commercial fish are _____ species?

Keystone (eg. large predatory fish)

What ocean habitats can trawlers damage/

Corals, rocks and sea plants

What is by-catch?

Loss of juveniles and non-commercial fish

Examples of bycatch

1. Sharks

2. Dolphins in tuna nets

3. Sea turtles caught and drowned in shrimp nets in the Gulf of Mexico

Why is international cooperation iportant in managing fisheries?

Because fish ecosystems span borders, and in international waters and fish migrate across borders

ITQ in Alaska

Salmon fishing since 1800s, with controls that recover the population

But by 1940, increased demand and better tech led to controls not being enough and by 1970, the fishing season was only 5-6 days long.

So in 1973, the fishery managers introduced ITQ (fixed or variable), distributed among long-term participators of the fishery.

Where else is ITQ used?

Large fishing companies in New Zealand

How big are most fishery zones?

200 miles

What zone did the US establish?

In 1976, the US established a 200 mile exclusive fishery zone around the US

Managed by National Marine Fisheries Service wthin the Department of Commerce and 8 regional councils advised by NMFS scientists.

When and where did a fishery collapse in the US?

In teh 1990s, the Northwest Atlantic region

Describe the Northwest Atlantic fisheries?

From NE US to SE Canada, except for a small area of Georges Bank, under US, historically among the world's most productive.

What fish depleted in the Northwest Atlantic fisheries? when

Cod and Pollock 1990s

How did the US and Canada respond to the depletion?

Imposed a mortarium on the region, passed the Sustainable Fisheries Act in 1996

Under the Sustainable Fisheries Act, what fishery was closed?

Cod

Endanger species under teh ESA's sustainable fishery means

no fishery

What kind of species are most targeted species?

Keystone