APES Unit 5

Tragedy of the commons (and how it applies to land use)

Definition: Individuals use public resource in their own interest, thereby depleting the resource

Individuals that use land for their own interest would deplete the land's resources without regard for sustainability

Sustainability

Practice of sustainable practices that can support future generations

Ecological Footprint

The amount of impact an individual has on the environment through their consumption and energy use

Best Management Practices

A variety of land management techniques designed to sustainably use the land in a way that protects water quality, biodiversity, aesthetics, and recreation

Ex: Habitat corridors, Biosphere reserves

Types/categories of land use

Urban/Suburban

Rural/Exurban

Commercial/Industrial

Transportation

Agriculture/cropland

Rangelands/grazing

Mining

Forest & Timber production

Recreation & wildlife conservation

Multiple-use land

A mix of uses of land(timber, ecological services, recreation, mining)

Categories/Types of protected public land

Ex: National Parks, Wildlife Refuge, Wilderness Area, National Forest

About 14.8% of the world's land is protected for conservation (up from only 8.2% in 1990)

But, protected lands might still be used for various human activities (timber, mining, grazing, energy extraction)

Loggers, miners, and wildlife poachers deplete natural resources.

Many are too small to sustain large animal species.

Many suffer from overuse, pollution, climate change, invasive species.

Types of forests & examples of resources provided by forests

Old-growth forest: uncut or regenerated forest that has not been seriously disturbed for several hundred years.

22% of the world's forest.

Hosts many species with specialized niches.

Second-growth forest: a stand(group) of trees resulting from natural secondary succession.

Tree plantation: planted stands of a particular tree species.

Logging techniques (advantages and disadvantages of clear cutting, strip cutting, selective cutting)

Clear cutting- Cheap, efficient, but not good for environment due to entire forest being cut(water erosion)

Strip cutting- Cheap, efficient, leave most forest in tact(not much water erosion), but takes long time to gain timber

Selective cutting- Environmental friendly, takes long time(human needed), most costly(economic disadvantageous)

Causes and effects of deforestation

Building roads into previously inaccessible forests paves the way for fragmentation, destruction, and degradation.

Losses are concentrated in developing countries (mostly for BIOMASS fuel).

Large areas of ecologically and economically important tropical forests are being cleared and degraded at a fast rate(provides 20% of Earth's oxygen and holds 50% of Earth's biodiversity; also is a carbon sink)

Large areas of tropical forest are burned to make way for cattle ranches and crops such as palm oil (this practice is known as "slash-and-burn" farming).

Methods to mitigate deforestation (such as reforestation)

emphasizing...

best management practices

maximum sustainable yield(harvesting trees no faster than they are replenished)

economic value of ecological services

afforestation(make new forest)

reforestation

protecting old-growth and vulnerable areas

using alternatives to wood

Forest fires and strategies to mitigate/reduce fires (such as prescribed burn)

Depending on their intensity, fires can benefit or harm forests. Small, naturally-occurring fires can(ground, surface):

Burn away flammable ground material.

Release valuable mineral nutrients.

Control pests and invasive species

Crown fires- are big fires that spreads quickly(bad)

To reduce fire damage(fire management):

Set controlled surface fires (PRESCRIBED BURN)

Allow fires to burn on public lands if they don't threaten life and property.

Clear small areas around property subject to fire.

Rangelands/Grasslands (why are they important, how are they used) Overgrazing

Almost half of the world's livestock graze on natural grasslands (rangelands) and managed grasslands (pastures).

Grasslands account for 70% of our agricultural land

Overgrazing occurs when too many animals graze for too long and exceed the carrying capacity of a grassland area.

Overgrazing compacts the soil, destroys natural vegetation, and leads to soil erosion, desertification

In US, public grazing lands are managed by the Bureau of Land Management

Taylor Grazing Act of 1934

Federal Land Policy & Management Act of 1976

Mining and mineral resources

Mineral resource or ORE: is a concentration of naturally occurring material in or on the earth's crust that can be extracted and processed into useful materials at an affordable cost.

A variety of methods are used based on mineral depth.

Types of mineral resources and how we use them

fossil fuels (coal, oil), metallic minerals (copper, iron), and nonmetallic minerals (sand, gravel)

Used for energy, consumer items, and roads/buildings

Processing/separating of mineral resources (smelting, gangue)

These vocabs are in like "steps"; smelting is when materials is transferred to factories, previous steps are done at the digsite

Overburden - the layer of soil and/or rock material that sits on top of the target material

Spoils - once the overburden is removed, it is placed in large piles or heaps, now known as spoils

Gangue - the worthless material that is found around and/or mixed with the desired material and must be removed

Smelting - the extraction or separation of the target mineral from its ore through heating and melting; chemicals can also be used to dissolve the unwanted material (such as cyanide in gold production)

Tailings - The waste material left over after the target mineral is separated from the ore; sometimes known as slag

Different types of mining

Placer mining- Traditional, miner looks for resource in river sediments, dredging(modern)

open-pit mining- Machines dig holes to remove resources

area strip mining- Miners strip away overburden, giant shovels removes minerals

contour strip mining- Strip away mountains(for coal seam(layer of coal))

mountaintop removal- Machines remove mountaintops for coal

subsurface mining- Used when resource are deep

underground, miners go underground into mine shafts with elevators

Consequences/Effects of mining (including spoils/overburden, subsidence, acid mine drainage, etc.)

Placer mining- can damage river with dredging; damage ecosystem with toxic substance(cyanide)

Area strip mining- causes spoil banks(easily erodible rocks) that can cause river blockage/damage water sources

Contour strip mining- causes highwall(easily erodible rocks) that can cause landslides

Open pit mining- Can contaminate groundwater with toxic materials

Mountaintop removal- Waste are dumped into water sources near the mountain

Subsurface mining- Dangerous for miners, lead to subsidence(cave-ins after mine shaft reinforcements degrade), damage groundwater, acid mine drainage(when resources like sulfur mix with water to create acidic water that damages water sources)

Reclamation

Restoring a piece of land after mining

Mining laws: General Mining Law, Surface mining control and reclamation act

Mining Law of 1872(General Mining Act)- Regulates mining of resources and allowed individuals to mine resources from federal land to encourage economic growth

Surface Mining Control and Reclamation Act of 1977- Regulates mining of resources, land needs to "minimally disturbed" with mining process, land needs to be reclaimed(restoring land) after mining

Impacts of Urbanization and urban/suburban sprawl (water use, resource consumption, pollution, etc)

Air pollution (and associated health problems)

Habitat destruction and fragmentation

Loss of biodiversity

Waste management

Increased consumption of goods

Energy consumption

Noise and Light Pollution

Access to water and food

Housing

Economic inequality

Urban (and suburban) sprawl

More paved (impervious) surfaces- not water permeable

Heat islands

Increased runoff and risk of flooding

Solutions for urbanization (SMART growth strategies, zoning, NEPA and Environmental Impact Statement -EIS, etc.)

Cities and suburbs should use zoning, laws, etc. to employ principles of SMART GROWTH

Seeks to make cities sustainable, while also encouraging economic development

National Environmental Policy Act (NEPA)

Requires Environmental Impact Statement (EIS)

Solutions can also use strategies for REMEDIATION and/or MITIGATION

Remediation - to make better or repair

Mitigation - lessen or reduce the risk or damage caused by human activity

Distinguish between undernutrition, malnutrition, and overnutrition

Undernutrition- People that can not meet their basic energy needs or protein

Malnutrition- People that can not meet their key nutrient needs

Overnutrition- People eating more required needs

Global food security/food distribution(government policies and food production)

Food security means that every person in a given area has daily access to enough nutritious food to have an active and healthy life.

Government...

Control prices to keep prices artificially low.

Provide subsidies to keep farmers in business.

Let the marketplace decide rather than implementing price controls.

We can increase food security by slowing population growth, sharply reducing poverty, and slowing environmental degradation of the world's soils and croplands.

Solution towards global food security- People in urban areas could save money by growing more of their food (rooftop gardens, green roofs, vertical farming, community gardens).

⅓ of world's food is wasted; wasted food accounts for 25% of water use

Famine (as well as reasons for famine and malnutrition)

Main cause for malnutrition/hunger is poverty

Causes for famine- poverty, climate change, high food prices, agriculture degradation, natural disasters, food shortages, disease, Lack of crop diversity making crops susceptible to disease(MAIN CAUSE)

Food consumption

Humans...

Need large amounts of macronutrients (protein, carbohydrates, and fats).

Need smaller amounts of micronutrients (vitamins such as A,C, and E).

Consumption has increased substantially over the recent decades with the exponentially increasing population

Three crops that make up majority of human diet

Wheat, rice, and corn provide more than half of the world's consumed calories.

Over-reliance on these 3 crops decreases biodiversity, makes more susceptible to disease

Meat consumption (how does meat consumption change as affluence changes?)

As world's population is becoming more affluent, meat consumption is increasing; more wealth = more opportunity to purchase meat

Green Revolution and history of human agriculture

Green Revolution refers to the modernization/mechanization of agriculture post-WWII

Since 1950, high-input agriculture has produced more crops per unit of land.

Food production has more than doubled since WWII

But, per capita food production is now leveling off

How has agriculture changed over time?

Modernization of agriculture allowed us to produce LOTS of food, but...

Lack of water, high costs for small farmers, and physical limits to increasing crop yields hinder expansion of the green revolution.

Since 1978 the amount of irrigated land per person has declined due to:

Depletion of underground water supplies.

Inefficient irrigation methods.

Salt build-up.

Cost of irrigating crops.

Modern agriculture has a greater harmful environmental impact than any human activity.

Loss of a variety of genetically different crop and livestock strains might limit raw material needed for future green and gene revolutions.

In the U.S., 97% of the food plant varieties available in 1940 no longer exist in large quantities.

Governmental agencies and laws related to food production and safety (USDA, FDA, FIFRA, Delaney Clause)

The Environmental Protection Agency (EPA), the Department of Agriculture (USDA), and the Food and Drug Administration (FDA) regulate the sales of pesticides under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA).

The Delaney Clause of the Food, Drug, and Cosmetic Act: "the Secretary of the Food and Drug Administration shall not approve for use in food any chemical additive found to induce cancer in man, or, after tests, found to induce cancer in animals."

Modern industrialized agriculture (agribusiness):

Advantages and disadvantages

Advantages - high food production

Disadvantages- Needs 17% of US's energy and 70-80% of US's water(high resources needed to sustain)

Energy subsidy (where does most of the energy in modern ag come from?)

Comes from cheap fossil fuels

About 10 units of nonrenewable fossil fuel energy are needed to put 1 unit of food energy on the table.

Mechanization

More machinery is being used to increase crop production efficiency

Resources used (water, fossil fuels, soil, pesticides, fertilizers, etc)

Pollution and environmental problems caused by modern ag (water pollution, antibiotic resistance, soil erosion, desertification, salinization, climate change, etc)

Due to high diseases, antibiotics is given frequently to animals= increasing evolution of diseases being immune to diseases(antibiotic resistance)

Animal waste can get washed to streams from floods- water pollution

Monocropping causes soil erosion as soil is repeated used for same crop

Overgrazing causes soil erosion and desertification

Constant watering of crops causes salinization due to the groundwater being used frequently to the point where ocean water merges with it(salt water intrusion happens only in coastal areas)

Constant usage of fossil fuels to power agriculture causes climate change

Monoculture (monocropping)

Single type of crop production

CAFOs

Concentrated animal feeding operation; bad for animal health

Pesticides:

Advantages and disadvantages of pesticides

Advantages: Save lives, increase food supplies, profitable to use, work fast, safe if used properly

Disadvantages: Promote genetic resistance, kill natural pest enemies, create new pest species, pollute environment, can harm wildlife and people

Types of pesticides

Insecticide: kills insects

Herbicide: kills plants

Rodenticide: kills rodents

Nematocide: kills worms

Pesticide resistance & pesticide treadmill

Pesticide resistance: Constant pesticide usage speeds up evolution in pests that become resistant to pesticides(superpests)

Pesticide treadmill: Humans trying to create pesticides that kill pests but pests evolve resistance simultaneously

Pesticide persistence and biomagnification, bioaccumulation

Pesticide persistence: How long pesticides last

Pesticide biomagnification: the buildup of a contaminant(pesticide) as it is passed up a food chain; organisms at the top of the food chain have the highest concentrations of contaminant

Pesticide bioaccumulation: the buildup of a contaminant(pesticide) in an organism over time

Integrated Pest Management (an other sustainable pest control methods)

Using a variety of methods for controlling pests; prioritizes the use of physical or biological methods instead of chemical pesticides; reduces use of potentially harmful chemical pesticides

Irrigation techniques (furrow, flood, spray, drip) and impacts of irrigation (on soil, aquifers, etc)

Furrow -dig trenches along crop rows and fill with water(no need for expensive tools); approx 35% water loss(need constant supply of water)

Flood - entire field is flooded with water(no need for expensive tools); 20-30% efficient, but can flood plants(need constant supply of water)

Spray - water is pumped into device with spray nozzles; expensive and uses energy, but 5-25% water loss

Drip - slowly dripping hose or pipe is laid on ground or buried below the surface; expensive to install, but only 5-10% water loss

Impacts of irrigation...

Groundwater(aquifer) depletion is a growing problem mostly from irrigation(Ogallala, largest aquifer in US)

Constant irrigation causes salinization(salt in soil) due to the groundwater being used constantly to the point where ocean water merges with it(salt water intrusion, only in coastal areas)

Constant irrigation causes waterlogging(water saturation in soil)

Irrigation causes groundwater over pumping leading to sinkholes(subsidence)

Constant irrigation causes high evaporation, poor drainage, salinization which means land can no longer be used

Soil erosion and degradation

Soil erosion is the movement of soil components, especially surface litter and topsoil, by wind or water.

Soil erosion lowers soil fertility and can overload nearby bodies of water with eroded sediment.

Soil erosion increases through activities such as farming, logging, construction, overgrazing, and off-road vehicles.

Soil is eroding faster than it is forming on more than one-third of the world's cropland.

About one-third of the world's land has lost some of its productivity because of drought and human activities that reduce or degrade topsoil.

Methods to protect soil (no-till, contour plowing,windbreaks, perennial crops, terracing, strip cropping, etc)

No-till/minimum till agriculture: Very narrow furrow is dug just big enough to plant seed; lessens soil erosion and nutrient loss; also maintains beneficial microbes in soil and lessens release of CO2 into the atmosphere

Contour plowing: Rows are plowed and planted so that they follow the shape of a hill(instead of up and down); slows runoff and reduces erosion

Windbreaks: Trees or shrubs are planted in long lines to help slow fast moving winds; lessens soil erosion

Perennial crops: comes up every year(does not need for replant)

Terracing: "Steps" are built into hillsides or mountains; commonly used in rice cultivation; prevent runoff of soil, nutrients, and water

Strip cropping: Planting alternating rows of 2 different crops(one is usually a more densely rooted crop) slows runoff and erosion

Riparian zones: A "buffer zone" of trees and shrubs is left along the banks of the stream; prevents soil/sediment from running into stream and decreases soil erosion and water pollution

Cover crops: Short or small plants(often perennials) are planted along/under other taller crops(like corn); reduces soil erosion, maintains soil biodiversity, and can also replenish nutrients(especially if legumes are used)

Rotational grazing: Only one portion of a pasture is used to graze animals at a time; the other parts "rest" so that grass and regrow; animals are moved from place to place; lessens overgrazing, soil compaction, erosion, animals can also be grass fed instead of corn fed

Regenerative agriculture: Using methods of soil conservation(like the ones listed above) to replenish soil nutrients and biodiversity, lessen erosion, and reduce climate change

Fish harvesting/Overfishing(Tragedy of the commons)

About 75% of the world's commercially valuable marine fish species are overfished or fished near their sustainable limits.

Big fish (such as cod, tuna) are becoming scarce; smaller fish are next.

We throw away 30% of the fish we catch (bycatch).

We needlessly kill sea mammals and birds because of fishing methods.

After many of the world's whale species were overharvested, commercial whaling was banned in 1960, but the ban may be overturned.

The International Whaling Commission (IWC) is the global intergovernmental body charged with the conservation of whales and the management of whaling.

Despite ban, Japan, Norway, and Iceland kill about 1,300 whales of certain species for "scientific purposes" or cultural heritage.

Meat is still sold commercially.

PROTECTING AND SUSTAINING MARINE BIODIVERSITY

Laws, international treaties, and education can help reduce the premature extinction of marine species (e.g. CITES, Endangered Species Act).

Since 1989 the U.S. government has required offshore shrimp trawlers to use turtle exclusion devices (T.E.D.).

There are a number of ways to manage marine fisheries more sustainably and protect marine biodiversity:

Fully protected marine reserves make up less than 0.3% of the world's ocean area.

Studies show that fish populations double, size grows by almost a third, reproduction triples, and species diversity increases by almost one fourth.

Some fishing communities regulate fish harvests on their own and others work with the government to regulate them

Use of quotas and licensing can maintain fish harvest at maximum sustainable yield

Aquaculture(fish farming)

Breeding, rearing, and harvesting of animals and plants in water environments

Can produce a significant amount of protein in a relatively small space

Supplies more than 50% of all seafood produced

Fresh or saltwater

Environmental impact of fish farming varies widely, depending on methods used, farm location, species being farmed

Problems include:

Concentrated fish waste

Leftover feed pellets

Disease and parasites (can spread to wild fish)

Escaped fish become invasive

Damage coastal habitat

Use fossil fuels and other resources

When good practices are used, it is possible

to have minimal impact:

Limit habitat damage

Minimize disease

Use natural feed

Limit escape of farmed fish

Sustainable Seafood

Sustainable seafood has been harvested or farmed using methods that protect long-term sustainability of fish populations, habitat, and fisheries-dependent communities

Choosing sustainable seafood:

Eat fish that are low on the food chain to avoid impact of biomagnification

Limit servings of fish (1-2 per week for most varieties)

Look for ecolabeling (such as Marine Stewardship Council or Fishwatch from NOAA)

Choose local and in-season seafood when possible

Role of genetic engineering in agriculture

GMOs: know what they are, examples, advantages and disadvantages of use

To increase crop yields, we can mix the genes of similar types of organisms and mix the genes of different organisms.

Artificial selection has been used for centuries to develop genetically improved varieties of crops.

Genetic engineering develops improved strains at an exponential pace compared to artificial selection.

GMOS: Genetically modified organisms/food

Process: Genetic engineering involves splicing a gene from one species and transplanting the DNA into another species.

Controversy has arisen over the use of genetically modified food (GMF/GMO).

Critics fear that we know too little about the long-term potential harm to human and ecosystem health.

One of most common genetic modifications is pesticide resistance, such as "Round-Up Ready" seed (which leads to increased use of Round-Up)

It is nearly impossible to prevent cross-pollination of GM plants

There is controversy over legal ownership of genetically modified crop varieties and whether GMFs should be labeled

Alternatives to conventional/industrial agriculture

Agroforestry, polyculture, crop rotation, cover crops, intercropping, rotational grazing, free range, etc

Many farmers in developing countries use low-input agriculture (subsistence farming) to grow a variety of crops on each plot of land (interplanting) through:

Polyvarietal cultivation: planting several genetic varieties.

Intercropping: two or more different crops grown at the same time in a plot.

Agroforestry: crops and trees are grown together.

Polyculture: different plants are planted together.

Crop rotation: Different crops are planted in alternating years; at least one is a legume(beans and peas) to cycle nitrogen; replenishes soil nutrients, reducing the need for chemical fertilizers

Cover crops: Short or small plants(often perennials) are planted along/under other taller crops(like corn); reduces soil erosion, maintains soil biodiversity, and can also replenish nutrients(especially if legumes are used)

Rotational grazing: Only one portion of a pasture is used to graze animals at a time; the other parts "rest" so that grass and regrow; animals are moved from place to place; lessens overgrazing, soil compaction, erosion, animals can also be grass fed instead of corn fed

Free range: a method of farming husbandry where the animals, for at least part of the day, can roam freely outdoors, rather than being confined in an enclosure for 24 hours each day.

Organic agriculture: know what it is, examples of organic methods, advantages and disadvantages

Organic agriculture: Seeks to produce food without the use of chemicals/synthetic pesticides, fertilizers, hormones, antibiotics

Compost(and other organic fertilizers): Organic material made from partially decomposed plant material(food scraps, yard waste, etc.); contains lots of nutrients and can also improve water retention; reduces need for chemical fertilizers and can prevent erosion

Green manure: Cover crop is grown then uprooted or plowed, then plant material is left to decompose; replenishes soil nutrients, reduces erosion; reduces need for chemical fertilizers

Integrated pest management(IPM): Using a variety of methods for controlling pests; prioritizes the use of physical or biological methods instead of chemical pesticides; reduces use of potentially harmful chemical pesticides

Biocontrols: Using natural predators to control pests(such as ladybugs to eat aphids); reduces use of potentially harmful chemical pesticides