Anthropogenic Global Changes Flashcards
Definition of Marine Pollution
- The introduction by humans, directly or indirectly, of substances or energy into the marine environment, including estuaries
- This introduction can result in deleterious effects such as harm to living resources and marine life, hazards to human health, hindrance to marine activities, impairment of the quality of sea use, and reduction of amenities.
what are contaminants?
Contaminants are substances present at levels above natural, local background levels in the marine environment. These substances can be physical (e.g., salinity), chemical (e.g., metals, nutrients), or biological (pathogens, microbial activity).
What are the types of pollutants/ contaminants?
Degradable Wastes: Examples include sewage, food processing waste, paper waste, and oil.
Persistent Wastes: Examples include heavy metals, plastics, and radioactive materials.
Dispersive or Dissipating Wastes: Examples include heat and acidity.
What are the anthropogenic Global Changes?
Land-Sea Interface Changes: Decline in seagrass meadows, coral reefs, and mangrove forests due to human activities.
Ports and Industry-Associated Changes: Dredging, land reclamation, fishing, aquaculture, oil and gas industry activities, mining waste, and seabed mining.
What are the climate change impacts?
Increasing temperatures leading to coral bleaching and marine heatwaves.
Ocean acidification causing changes in water chemistry and affecting calcification.
Increased hypoxia due to warmer temperatures and eutrophication.
Sea-level rise causing coastal erosion, habitat loss, and infrastructure stress.
What is the Ocean Health Index (OHI)
- Measures how well coastal countries optimize ocean benefits across various goals such as biodiversity, clean waters, sense of place, carbon storage, food provision, and natural products.
- Considers present status, trend over the last five years, pressures, and resilience factors
What are the sustainable development goals?
- UN initiative to conserve and sustainably use oceans, seas, and marine resources for sustainable development.
- Aims to mitigate major pressures, including climate change, on marine ecosystems and resources
Land sea interface changes. Problems:
Population increased
1990 = 5.3bn
2024 = 8.1bn
2080 = 10 bn
Coastal waters accounts for just 5% of earth land area but 39% of pop lives within 100km
60% of megacities within 100km
More issues of land-sea interface changes
- Global extent of seagrass meadows is decreasing sharply (30% less than pre industrial estimates)
- 58% major reefs, 64% mangrove forests, 62% of major estuaries near urban centres
20% of coral reefs and 35% of mangrove forests have been lost within last 20 years
What is eutrophication ?
High input of nutrients promoting algal growth resulting is deoxygenation of coastal waters, increase of turbidity and loss of biodiversity
What are pesticides?
Manmade chemical compounds designed to kill pests
- Toxic
What is an example of a pesticide ?
Organochlorine
Organophosphate
What are trace metals?
Numerous compounds widely used in industry/ transport
- Cu, Pb, Hg
What are the impacts of trace metals?
Toxic effects at all trophic levels
evidence of sub-lethal effects on living organisms affecting behaviour
What are some other emerging contaminants?
PCPs, plastics, nano materials, pharmaceuticals and narcotics
Ports and Industry-associated changes
90% of goods transported by ships - 25% crude oil
Growth of ~7%/ year - port cargo = 57% by 2030
Ship size increases
What are the risks of ports and industry-associated changes?
Oil spills, noise, invasive species through ballast waters, antifouling paints and emissions of air pollutants and greenhouse gases
