APES Unit 5: Land and Water Use

Tragedy of the commons

When individuals use shared resources in their own self-interest rather than in keeping with the common good, thereby depleting the resources

Solutions to the tragedy of the commons

Regulate use: hunting/fishing licenses, land use permits, quotas, selective cutting
Replenish after use: replant trees, throw back gravid fish, rotate grazing grasslands
Ensure compliance: treaties, laws, fines, incentives (subsidies, debt forgiveness)

Subsidy

Money for work equipment, cheaper expenses

Tragedy of the commons can't occur on \_________ lands

private (has to be on a COMMONS)

Tragedy of the commons can't be...

accidental

One way a local community might regulate a shared and limited resource and reduce the tragedy of the commons is to...

divide the resources into parcels and assign them to individuals

Albedo

Ability of a surface to reflect light

Clearcutting

The process of cutting down all the trees in an area at once

Impacts of clearcutting

Loss of ecological/economic services, reduced biodiversity, more invasive species from roads, decreased soil albedo, more water evaporation, desertification, soil erosion

How does clearcutting affect nearby aquatic environments?

Soil compaction from equipment and vulnerability to wind \= less infiltration \= soil erosion and sediment runoff into nearby waterways \= increased turbidity \= decreased albedo \= higher water temperatures \= less dissolved oxygen \= decreased fish biodiversity

Green revolution

A shift to new agricultural strategies and practices in order to increase food production for a growing population

Parts of the green revolution

Mechanization, monoculture, artificial fertilizers, artificial pesticides, irrigation, GMOs

Pros of mechanization

No human labor, can be specialized, easy to use, efficiency\=profits

Cons of mechanization

Fossil fuel use

Pros of monoculture

Easy to plant, high yield, efficient

Cons of monoculture

Loss of habitat and biodiversity, loss of ancestral varieties, less adaptations for catastrophic events, degrades soil

Haber-Bosch process

N2 + 3H2 --\> 2NH3

Pros of artificial fertilizers

Can be customized, mass produced, easy to ship/store, ensures a higher crop yield due to max growth

Cons of artificial fertilizers

Can easily dissolve in runoff, eutrophication, disrupts nitrogen cycle

Pros of artificial pesticides

Same conveniences as fertilizers (quick, easy), ensures a higher crop yield due to minimized loss from pests

Cons of artificial pesticides

Possible extermination of nontarget species, persistence, possible human health effects (can contaminate groundwater), evolution of pesticide-resistant pests

GMOs

Human directed evolution that selects beneficial traits in a species by inserting genetic material of normally incompatible species into its DNA, thus creating new traits in the species (genetic engineering)

Pros of GMOs

Crops can be drought, heat, and salt tolerant, can create their own insecticide, can become herbicide-resistant

Cons of GMOs

Weeds can become herbicide-resistant, insecticide producing crops could kill nontarget species, can lead to insecticide-resistant pests, reduction in genetic diversity, pesticide treadmill

Which of the following statements best identifies the author's assumptions in terms of a new green revolution? (AP)

Current agricultural practices and strategies need to be evaluated in order to meet the demand for increased food production

Which of the following statements best identifies the author's perspective in terms of government funding for future agricultural research?

More funding is continually needed because the agricultural research programs have never been completely financially supported

Which of the following statements best identifies the author's perspective in terms of utilizing science technology for future agricultural advances?

The only way to meet the global demand for more food is to fully utilize new science technologies to advance agriculture

Arable land

Land suitable for growing crops

Cons of tilling

Leads to bare soil and erosion, eutrophication, turned soil \= worse soil structure and sequestered carbon released as CO2

Slash and burn agriculture

Method of cultivation in which forests are burned and cleared for planting, ash is used as fertilizer (typically found in developing countries in tropical rainforests where there is low soil nutrients)

Slash and burn agriculture is bad for the environment because it's

unsustainable

Cons of slash and burn agriculture

Desertification, soil erosion, decreased albedo, increased evaporation, decreased infiltration, releases CO2

Organic fertilizer comes from...

animal waste

Pros of organic fertilizer

Improves soil structure and health

Cons of organic fertilizer

Must be gathered, nutrient levels unknown, harder to use, eutrophication

Synthetic fertilizers are made using the...

Haber-Bosch process

Pros of synthetic fertilizers

Customizable macronutrients and easy application

Cons of synthetic fertilizers

Water soluble, overused, doesn't improve soil structure, can cause eutrophication

Too many pesticides can result in a...

pesticide treadmill

Pesticide treadmill

A cycle of pesticide development, followed by pest resistance, followed by new pesticide development (constantly having to develop new chemicals)

Pesticides DON'T cause \__________________, unlike fertilizers

eutrophication

Flood irrigation

Flooding an entire field with water by diverting waterways

Pros of flood irrigation

Easy, inexpensive, mechanization NOT required

Cons of flood irrigation

Requires nearby water, not for all plants, land has to be graded, levees needed*, 20% of water lost to evaporation, waterlogging/salinization, not great on sandy soil

Pros of furrow irrigation

Easy, inexpensive

Cons of furrow irrigation

Not efficient on SANDY soil, difficult to apply small amounts, 33% of water lost to evaporation, soil erosion

Which of the following is NOT an issue with water diversion for agriculture?

Decrease of sedimentation upstream

Cons of water diversion

Disruption of fish migration, decrease in water availability for riparian zone organisms downstream, increase in salinity in estuarine habitats downstream (estuary is where freshwater meets saltwater, and diversions for ag reduce freshwater flow)

Which of the following statements correctly pairs an irrigation method with an advantage or disadvantage? (AP)

Flood irrigation is often used in agricultural fields, however, it increases surface erosion and salinization of the soil

Which of the following irrigation methods is most likely to result in salinization of the soil, especially if the agricultural fields are located in a warm climate with consistent sunlight?

Furrow irrigation (because it is the least efficient, *remember more evaporation \= more salts left behind)

A farmer grows several crops on a farm that has mostly shallow, sandy soil. Which of the following irrigation methods would be the best suited for this farm?

Drip irrigation

Pros of spray irrigation

precision application, supplements can be added to water, efficient (25% or less lost to evap), can be programmed

Cons of spray irrigation

Expensive, uses fossil fuels, nozzels can clog with sediment

Pros of drip irrigation

VERY low evaporation rates (5%), reduces nutrient leaching, no land grading needed, great for sandy soil because water can't infiltrate as quickly

Cons of drip irrigation

VERY expensive, clogs easily

Which if the follow irrigation methods is the MOST efficient with water?

Drip irrigation

Waterlogging

Water saturation of soil that fills all air spaces and causes plant roots to die from lack of oxygen; a result of overirrigation (seen in flood irrigation)

Solutions to waterlogging

Add sand to soil to prevent saturation, using drip irrigation

Salinization

Accumulation of salts in soil that can eventually make the soil unable to support plant growth (causes desertification)

Solutions to salinization

Flush salt fields with water

Ogallala aquifer

World's largest aquifer; under parts of Wyoming, South Dakota, Nebraska, Kansas, Colorado, Oklahoma, New Mexico, and Texas (the Midwest); Holds enough water to cover the U.S. with 1.5 feet of water; being depleted for agricultural and urban use.

Which of the following irrigation related problems would NOT require large amounts of freshwater for remediation?

Waterlogging

GMOs cause loss of ancestral plant varieties. Which if the following is NOT an advantage of using GMOs?

Decreased genetic diversity in crops

Mining methods

Open-pit, strip, placer, mountaintop removal

Tailings

Rock and other waste materials removed as impurities when waste material is separated from the ore

Spoils

Unwanted rock and other waste materials produced when a material is removed from the earth's surface or subsurface by mining

Which of the following is LEAST likely to be an environmental problem associated with abandoned tailings?

Excess nutrient load in nearby bodies of water (not all runoff is nutrient rich, don't forget tailings can cause desertification)

A breach in tailings that leaks in water can cause...

acid mine drainage

Accessing lower-grade ores requires an \__________ use of resources that cause more fossil fuel emissions, waste, and pollution

increased

CAFO

Concentrated Animal Feeding Operation

Cows emit \________ through farts

methane (GHG)

Cons of manure lagoons

Leakage can cause:
Increased turbidity \= decreased \= albedo \= increased water temp \= decreased DO \= decreased NPP
Also:
Increased nutrient load \= increased decomposition by aerobic bacteria \= eutrophication \= decreased DO and aquatic NPP

Fecal coliforms

Bacteria like E Coli in animal waste which can leach into human drinking water causing sickness

Having animals clumped together in the same place can lead to...

soil compaction and erosion, no infiltration, and damage to riparian zones in local waterways

Reducing meat consumption will reduce which of the following greenhouse gases?

CH4 (methane)

Pros of CAFOs

Minimizes land costs and improves feeding efficiency

The DO levels of a river have dropped over the past week. There is a CAFO near the river. How might the CAFO have impacted the river's DO?

The CAFO's manure lagoon has leaked into the river

Pros of free range grazing

No antibiotics needed

Cons of free range grazing

Nonnative organisms in habitat can interfere with biodiversity, higher cost, no growth hormones

Overgrazing

Destruction of vegetation caused by too many grazing animals consuming the plants in a particular area so they cannot recover

If a consumer chooses free-range beef over CAFO beef, which of the following will be reduced as a result

Use of antibiotics

Types of fishing methods

Long-line, gillnet, purse seine, trawling, sonar

Bycatch

Nontarget species that are fished and aren't nicely thrown back

How to make fishing more sustainable

Catch limits based on MSY, limits on fish age/size, modified techniques to reduce bycatch, laws/treaties

Which of the following is NOT a benefit of living in an urban city?

Increased residential space per capita

Urbanization impacts on the hydrologic cycle

Increased need for water \= water diversion projects \= impacting organisms that live in that environment, upstream flooding and decomp problems, downstream there won't be enough sediment

Saltwater intrusion

Coastal areas get water from separation of freshwater aquifer where saltwater is separated by pressure. As you begin to draw more water than is recharged, saltwater intrudes into the freshwater aquifer

Impacts of impermeable surfaces

Water runoff instead of infiltration \= nonpoint source of pollution, loss of vegetation \= loss of water sink

Urbanization impacts on the carbon cycle

CO2 release \= worse climate change, release of impurities (air is a global COMMONS), respiratory illness

Urban sprawl

When people spread out into suburbs

Urban heat island effect

Roads, buildings, and impermeable surfaces have a LOW albedo which leads to higher temperatures day and night than surrounding areas, more vegetation \= cooler temps

Waste heat from fossil fuel emissions...

can't be dispersed as well in a city

Urbanization remediation

More vegetation (plants take up CO2), more public transportation, permeable pavement, urban planning, smart growth, remediate brownfields

I \=

PAT

MSY

Maximum sustainable yield (50% k)

Commercial fisheries often harvest more than 50% of the k of a fish population. What is the most likely scenario that will arise from this practice?

A higher percentage of fish harvested are younger and smaller in size

Which of the following is the independent variable in this study (AP pallet mcq)

The type of pavers used in the pallets

IPM

A combination of methods used to effectively control pest species while minimizing the disruption of the environment (includes phys, bio, and limited chem methods)

The goal of IPM is to...

reduce the amount of pesticides to reduce the pesticide treadmill and poisoning of nontarget species

Bio controls

introduction of natural pest predators