Human impacts on marine ecosystems (Pollution (Endocrine disruptors (PCB,…
Human impacts on marine ecosystems
Non-natives that may or may not do harm.
(no natural predators, voracious predator themselves, fast reproduction).
Ballast/ boat hull
should have most invasive species in the world >250 species. (Introduced from ships)
only has 6 invasive species from ships
bay >150 invasive species, difficult to find native species
50% of population living within 100km of coast
Prevent erosion of reclaimed land
Protection against storm surge
Sea level rise
SG 20% coastline with seawalls
Turned into prawn farms
Biggest cause of destruction? Agriculture creep, reclaiming mangrove 80%
Damming of rivers
no release of sediments to mangroves, ultimate loss of coastal habitat.
PCB, PBDE (fire retardants), POP (persistent organic pollutant)
Smothering of benthos
Not a good substrate
LAFG (lost and abandoned fishing gear), ghost fishing.
Mostly come from land ~80%, shipping industry
Ships (150 – 190db)
Impairs health and physiological development
• Harmful algal bloom (poison, bioaccumulation in marine animals eg shellfish
• Biomagnification in higher trophic level
• Dead zones
• Macroalgae growth
Affects coral spawning which requires moonlight
Waste products of minerals exploitation is dumped in intertidal or near-shore.
Pumps warm water into ocean
Non renewable resource
eg oil, natural gas, sand/gravel (dredging), tin, salt, metallic nodules
Releases toxic, nutrients
All other methods of fishing
Limiting time at sea
Leading edge: introduction and expansion into new habitat
Limited by light and temperature
Temperature affects conductivity of echolocating organism
Range shift in terms of geography and depth.
Increase in sea level, some species can move upwards (range shift) and settle on seawalls etc
Trailing edge: localised extinction, species no longer found in its original habitat
Reduction in O2 in ocean
Sea level rise (thermal expansion).
Melting of polar ice, ice shelf (already floating in water, volume contributed to sea level rise is little).
Melting of terrestrial glaciers, ice sheet contribute significantly to sea level rise.
Permafrost methane underneath ice sheet and glaciers. Melting releases methane!
Physio-thermal regulation (energetically intensive, diversion of resource away from reproduction etc)
Coastal squeeze of mangroves
Via flooding, generates more sediments
Reduction in terrestrial land, especially islands
Increase in CO2 from combustion
Thinning of ozone layer from release of CFC, HFC
Unrelated process (erosion and calcification). Separate processes.
Photosynthesising organism benefit from ocean acidification
eg Seagrass (need CO2,increase in productivity…)
-phytoplankton (dinoflagellates, coccolithophores) Different groups different responses
Blast fishing and cyanide fishing
Restocking giant clams
Enhancing biodiversity on seawalls
International Coastal Cleanup