APES U5

APES Unit 5

Tradedy of the Commons: 

Common resources which are available for ALL humans to use 

• Often exploited at unsustianable rates 

• You may benefit economically but at a price (depleted resource)

• Groundwater depletion is a good example! 

Water Resources:

• You should be familiar with the Ogallal Aquifer; found kind of in the middle of the United States. This is the largest aquifer in the US and one of the biggest ones in the world. This aquifer has been overrated and is nearing depletion due to human use only.

• Only a small percentage of accessible water is freshwater.

• Ground Water: aquifers 

• Aquifers are often over drafted - more water is removed than able to recharge (cant recharge fast enough)

• Review cone of depression

• Impacts:

  • Subsidence (land water sinks down) -> Over time, the land will actually sink down where were pull water out 

  • Saltwater Intrusion

Irrigation:

TOP = MOST EVAPORATION

• Furrow

• Floors

• Spray (lawn beeing water)

• Drip (holes drip water-> least)(but is the most effective)

IMPACT: Salonation, avoid with drip, fix with flushing 

Issues with agricultural practices;

1. Tillage is preparing land for crops by loosening and mixing the top inches of solid, which can lead to erosion. This is bad because it can lead to the loss of topsoil it will be hard to grow plants. 

2. Deserfitfication; loss of soil produtcity (used it so much and does not have anything left to provide)

3. Salinization: caused by irrigation evaporation leaving behind salt and minerals in the soil 

Mining

Ore- rock which contains prfotitable amounts of minerals (like iron)

Reserves - source we can mine from

Overburden - soil removed when mining 

Spoils - waste created by mining 

Taillibs - reduce frpm mining operations 

What is bycatch

Knowing urban blight 

Review:

Clearcutting & Deforestation;

• Definition: Clearcutting is when all of the trees in an area are cut at the same time. 

• Direct Effects of Clearcutting;

  • Soil erosion, removes organic material, decrease in biodiversity, changes temeperates, and flooding & landslides, and change in CO2 level

• Deforestation is the act of taking forest areas and making them into non forested areas by removing trees & remaining organisms. 

  • CONSEQUENCES: reduces air filtering and carbon storing services, cutting trees down releases CO2, Slash & Burn technique method of land agriculture where cutting trees and burning thek releases CO2, N2O, and water vapor into the atmosphere (GHGs) 

  • It allows runoff, changes local climate patterns, and decreases soil fertility. 

The Green Revolution; 

• Shift from small, family operated farms to use of technology and industrial-scale agribusiness 

  • The first green revolution involved the use of inorganic fertikizers, synthetic pesticides, new and more efficient methods of irrigation, and the begging of developing high - yielding crop seeds that were also disease resistant and more tolerant of changing climatic conditions. (summed up; herbicides, pesticides, and inorganic fertilizers) 

  • The second green revolution involved the free-trade agreement and the use of new GMOS. 

  • These revolutions did lead to soil erosion, biodiversity loss, and ground & surface water contamination. 

• Vocab word: Mechanization is the increased use of factors and tilling fields and harvesting. It leads to increased yields and profits. BUT also increases reliance on fossil fuels.

• Vocab: HYV (High Yield Variety) Crops - hybrid or genetically modified crops that produce a higher yield (amount of crop produced per unit of area)

Pesticides 

• Chemicals that are toxic to pests

• Examples;

• Rodenticides kill rodents

• Fungicides kill fungi

• Insecticides kill insects

• Herbicides kill plants

• Can cause pests to become resistant to pesticide overuse 

  • Genetic biodiversity gives some pests resistant traits to pesticide overuse 

• Increase in use of synthetic pesticides 

Integrated Pest Mangement (IPM)

• Basic: Uses variety of pest control methods that control env.disruption and pesticide use

• Bio control (bringing in a natural predator or parasite to control the pest)

• Crop Rotation

• Intercropping ; “push-pull” system can be used 

• + reduces death and mutation

• + reduces effects of  human consumers of produce 

• + reduces contamination of  surface and groundwater 

• - can be more time consuming and deadly 

Imapcts of Oversfishing

• Fisheres: populations of fish used for commercial fishing

• Fishery collapse: when overfishing causes 90% population decline in fishery 

• Leads to decreased biodiversity in fish and lost income for fisherman 

• Bottom trawiling: harmful fishing method that involves dragging a net on the ocean floor 

Vocabulary: 

Monocroping; growing one single species of crop

Bycatch: unintended species like dolphins whales and turtles caught in nets

IMPORTANT MINING:

Basic Information You must know: