What is “The Tragedy of the Commons”?
The tragedy of the commons is the idea that when individuals will only use shared resources for personal gain, leading to collective depletion (e.g., overfishing, groundwater overdraft).
What is sustainable yield?
The maximum amount of a resource that can be used without reducing its ability to regenerate in the future.
What is strip mining?
What is the environmental impact?
Removal of large surface layers of soil/rock to expose ore.
Environmental impacts: habitat loss, erosion, acid mine drainage.
What is subsurface mining?
What are the impacts?
Extraction of minerals deep underground.
Impacts: dangerous for workers, acid drainage, sinkholes.
What is acid mine drainage?
When sulfide minerals exposed to air + water produce sulfuric acid, contaminating waterways and lowering pH.
What is reclamation?
Restoration of mined land to natural or economically usable state (soil replacement, re-vegetation).
What is clearcutting?
What are the impacts?
Removal of all trees in an area.
Impacts: habitat fragmentation, increased erosion, warmer streams, decreased biodiversity.
What is selective cutting?
Removal of only certain trees.
Impacts: less erosion, more sustainable, maintains forest structure.
What is deforestation’s global impact?
Increased CO₂, loss of biodiversity, soil degradation, altered water cycles.
What is overgrazing?
Livestock eating vegetation faster than it regrows.
Impacts: desertification, soil compaction, erosion.
How can rangeland sustainability be improved?
Rotational grazing, limiting herd size, restoration reseeding.
what are some Green Revolution products?
Synthetic fertilizers, pesticides, high-yield varieties, irrigation technology, mechanization.
What is monocropping?
What are the impacts?
Growing one crop on the same land repeatedly.
Impacts: soil degradation, pest vulnerability, reduced genetic diversity.
What is slash-and-burn agriculture?
What are the impacts?
Cutting vegetation then burning it to clear land.
Impacts: nutrient-rich ash short term → long-term soil depletion + carbon emissions.
What is desertification?
Loss of productivity in arid/semi-arid lands due to overgrazing, deforestation, poor agriculture.
What is salinization?
How do you fix it?
Salt buildup in soil from evaporation of irrigation water.
Fix: flush soil, switch to drip irrigation.
What is waterlogging?
What is the cause?
Soil saturation that starves roots of oxygen.
Cause: over-irrigation.
What are some irrigation teqniques?
- Furrow irrigation: Trenches filled with water.
Efficiency: low (lots of evaporation/runoff).
– Flood irrigation: Field flooded.
Issues: salinization, waterlogging.
- Sprinkler irrigation: Sprayed from overhead.
Efficiency: moderate; high cost. - Drip irrigation: Tubes drip water directly to roots.
Efficiency: highest; reduces salinization.
Broad-spectrum pesticide
Kills many species, including beneficial ones.
Pesticide treadmill
Pests evolve resistance → farmers use more or stronger pesticides.
IPM (Integrated Pest Management)
Uses biological control, habitat manipulation, limited chemicals.
Goal: minimize environmental damage.
What is a fishery collapse?
90% population decline (often due to overfishing).
What is bycatch?
Unintended species caught (turtles, dolphins).
Aquaculture benefits?
High efficiency, reduces wild fish depletion.
