Marine Pollution Midterm

Energy Imbalance

if incoming and outcoming energy don’t match, planet is warming or cooling

• earth receives energy (radiation) and emits energy (radiation)

Guy Callendar

• discovered rising global temperatures (by 0.3 degrees C)

• said CO2 emissions from industry were responsible

• largely ignored

Charles David Keeling

• took measurements of CO2 in atmosphere

• most widely recognized time series of atmosphere CO2

• linked rising levels of CO2 to warming of planet

Methane

• natural and human-related sources

• contributes 30% of global warming

• remains in atmosphere for ~12 years

• MH4 → ground level ozone harms health, crops and ecosystems

Natural Methane

wetlands (microbial breakdown), lakes, rivers, permafrost, ocean sediments, wildfires, geological seepage (natural gas seeps), termites, animal digestion

Human-Related Methane

oil/natural-gas, coal mining, landfills, wastewater treatment, livestock, rice cultivation, burning of biomass and fossil fuels

*biggest is fossilfuels, agriculture and waste management

Methanogenesis

• carried out by archaea under oxygen-free conditions

• produces methane

• hydrogenotrophic = CO2 is reduced using hydrogen

• acetoclastic = acetate is split

*typically used in wetlands, sediments, landfills, and animal digestion

Photosynthesis

autotrophs use inorganic substances to produce organic matter

• PRIMARY PRODUCTION

Chemosynthesis

oxidize reduced inorganic substances to gain energy which is used to fix inorganic CO2 to produce organic matter

• PRIMARY PRODUCTION

Redfield Ratio

found that in open ocean phytoplankton, carbon, nitrogen and phosphorous occur in ratio 106:16:1

Macronutrient

element necessary in greater than 500 ppm for growth of plant

EX. nitrogen and phosphorus

Micronutrients

element necessary in small amounts <50 ppm for growth of plants

EX. iron

Primary Source of Nutrients

atmosphere (N2, CO2) and rock weathering (P, Fe)

Secondary Source of Nutrients

• dissolved sources in oceans, river water, organic matter and waste water

*coasts receive nutrients from atmosphere, river, land run-off, groundwater, ocean and ground

Nitrogen Fixation

• diazotrophs fix atmospheric dinitrogen gas into ammonia (NH3)

• cyanobacteria fix nitrogen (eccessible to foodweb)

Nitrogen Pollution

• most common causes of water quality impairment of inland and marine waters

• nitrogen introduction to ocean is increased by 50% by humans

• anthropogenic fixed nitrogen results in 30# fo ocean’s non-recycled N supply and 3% of annual new production

• nitrifying bacteria convert nitrogen runoff into mobile NO3, leading to eutrophication of coastal waters (hypoxic zones) - also increases amount of CO2 pulled into ocean

Anthropogenic N sources

• industrial processes (agricultural practices and fossil fuel burning) reduce N2 to NH4

• contribute double natural rate of terrestrial N fixation

Haber-Bosch Process

• Atmospheric nitrogen (N2) reacts with hydrogen to produce ammonia (NH3)

• adsoption → separation (rate limited) → adsoption → separation → reaction → desoption

• used to make fertilizers

  • increased the amount of excess nutrients in runoff and atmosphere (denitrification)

N2O Greenhouse Gas

• denitrification forms N2O under anoxic conditions which releases to atmosphere as greenhouse gas

• marine and terrestrial sources

• 120 atmospheric lifetime

• heat traps more than 310x better than CO2

Phosphorous Pollution

• naturally comes from weathering of rocks/soil

• anthropologically comes from sewage and transported to ocean

• 3 formes: dissolved inorganic, dissolved organic, particulate organic

• increases in summer due to anoxic conditions in sediments releasing phosphate

Phosphorous Cycling

• egestion and excretion of protozoan/metazoan consumers mineralizes phosphorous

• anaerobic conditions from release of iron and magnesium remobilizes it

Eutrophication

body of water becomes enriched in dissolved nutrients that stimulate growth of aquatic plant life

• can generate hypoxia (low oxygen), anoxia (no mesurable oxygen) and hydrogen sulfide

Geomaterial Plastic

• magnitude of plastic pollution means plastic is considered a geomaterial

• chemistry no previously seen in earth’s history

• quantities of plastic present rivals quantity of natural organic carbon

• provides geological record of humanity’s rise to global prominence

Organic Carbon

• fuels life and forms elemental backbone of biomolecules

• stored in fossil fuels

• raw material for plastic

• warms planet through combusion

Leo Baekeland

made first synthetic plastic

Alexander Parkes

• made first manmade plastic

• derived from natural cellulose and predecessor to celluloid

Plastic-Carbon Cycle

• industrial production of high-molecular-weight polymers

• plastics degrade into low-molecular-weight, nonpolymeric compounds (dissolved and gas products)

Plastic Production

• large-scale production began in 1950s and is accellerating

• plastic-carbon has accumulated and exceeds human and animal biomass

• carbon loading in soil and water alters biogeochemical cycles (primary production and nutrient cyfcling)

Plastic Photodegradation

degredation of plastics in environments through radiation

• often accelerates removal the longer plastics reside in sunlit environments

  • migharise from accumulation of photoreactive oxidized groups and increase in surface area-to-volume ratio of plastics fragment

Plastic Biodegradation

intestinal microbes of insect larvae and free-living microbes degrades C-C bonds of plastics using special enzymes (evolved to degrade component of wood)

• took long time for enzymes to evolve

• reside in landfills and dumps

Ocean Plastics

• small, urbanized rivers export more plastics than biogenic carbons

• 40% of plastics entering ocean sink

• microplastic carbon contributes to large amount of nonliving OC in surface waters

Crude Oil

• large industry

• formed by decay of organic matter from jurassic period plankton being exposed to heat and pressure

• made of many chemicals

• measured by barrels (bbl/bo) = 42 gallons

Oil Pollution Act of 1990

• placed liability on responsible parties

• required phasing out of older vessels and implemention of new technology and safety procedures

Deepwater Horizon

• oil rig exploded and produced largest spill of oil in marine drilling operations (750000 m3 of oil released)

• located near mississippi canyon area in northern gulf

• oil and gas spilled for 87 days

• sweet crude oil was spilled (low in sulfur; high in gasoline)

• contaminated over 92000 square miles of surface water

• declined barataria bay bottlenose dolphin population by ½

• killed sea turtles, shorebirds, and oysters were killed ( sustainability of gulf oysters at risk)

Exxon Valdez

• tanker struck Prince William Sound’s Bligh Reef

• spilled 11 million gallons of crude oil

• killed orcas, harbor seals, sea otters, seabirds, bald eagles and salmon

Taylor Energy

• destruction of oil platform during hurricane ivan spilled off coast of louisiana

• ongoing

• 3.3 million barrels of oil released

• impact plankton, fish, invertebrates, birds, mammals, and turtles

• 2022 federal settment provided money for plugging wells (work not yet completed)

Halogenated Hydrocarbons

• burning releases vinyl chloride, phogene and combustile liquids

  • dioxin and dioxin-like compounds are created and released

• long lasting, conservative, pollutants in marine environment

• most contain chlorine

• common in pesticides, coolants, aerosol propellants, electrical insulation, plastics, adhesives

• cheap and easy to produce

• stable and long lasting

• effective against malaria and other diseases

• no visible imediate negative effect on humans or animals

• bioaccumulates in fish and marine animals

Dioxin

• most toxic anthropogenic chemicals

• cause cancer, reproductive and developmental problems, damage to the immune system, and can interfere with hormones

• no safe level of exposure

DDT

• chlorinated organic molecule

• first synthesized in 1874

• insecticidal effect discovered by Paul Hermann Muller (awarded nobel prize)

• used to fight against malaria

• cancelled by EPA in 1972 due to environmental effects and human health risk

• probable human carcinogen (breast cancer)

• WHO supported indoor use in african countries for malaria

• not broken down rapidly, bioaccumulated in fatty tissues (toxic in animals)

• mobile in soils and aquatic sediment

• live pu to 15 years in soils and 150 years in marine

Polychlorinated Biphenyls

• special class of electrically insulated compounds

• used in transformers, capacitors, and epoxy paints

• limited by toxic substances control act (1976)

General Electric Company

• discharged lots of PCBs into hudson rivers from two capacitor manufacturing plants

• about 200 miles of river is superfund site

PCBs

• 20% of pcbs present in upper layers of ocean

• high vapor pressures which volatilze when spread over large surface area (soil/water)

• atmospheric residence time = few months

• limited by toxic substances control act (1976)

Tetrachlorodibenzo-p-dioxin

• byproduct of chlorinated phenyl compounds (herbicides)

• non-biodegradable

• highly toxic to most mammals

• in incineration emissions and other waste disposal environments

Buckeye Paper Mill

• discharges toxic sludge (wastewater) into almost entire flow of fenholloway river

• dumped dioxins and nutrients

• worst polluters in state

• pollutes gulf of mexico delta (leaves 17 square miles lifeless)

• legal due to attempt to attracting industry

• FDEP made them attain a fishable/swimable status for fenholloway river

  • instead of cleaning up, polluted water is carried to gulf of mexico

• turned fish trans? maybe humans too

Mercury

• liquid at room temp

• produce 8 tonnes/year

• gold mining, electronics, batteries, fluorescent bulbs

• forms amalgams with other metals

Mercury Pollution

• naturally found in geothermal environments, transformed by microbs and weathering

• anthropogenically released by burning of coal

• can travel long distances as gas (stays in atmosphere for 6-24 months)

• atmospheric Hg deposited on terrestrial and aquatic ecosystems (main route to ocean)

Minamata Convention 2013

• signing led to halt of anthropogenic mercury production

• 170 states and EU have signed and ratified, accepted, approved, or acceded to convention

Methyl Mervury

• microbs convert Hg to methyl mercury

• absorbed quickly by organisms

• more toxic and bioaccumulative

• harmful to humans and fish-eating animals (cause reproductive issues)

• decreasing pH and increasing dissolved carbon = increase

• UV breaks down methyl mercury to release as gas

• white canned tuna 3x mercury levels than light canned tuna

Chisso Corporation

• released methyl mercury to industrial wastewater

• bioaccumulated in shellfish and fish

• caused mercury poisoning in local population

Qiu et al.

• global mecury increased 330% during 1960-2021

• mercury emissions declined since 1990s

  • declines offset by rapid growth of mercury emission in southern hemisphere countries

• countries in southern hemisphere produced 2/3 of global emission

• global emissions continue to rise

Kivenson et al.

• surveyed offshore california with underwater vehicles where MCC is located

• found discarded waste containers where DDT was dumped

  • srtill affects suboxic benthic environment

• DDE, DDMU frequently detected in environement

  • DDE is most abundant (result of abiotic/aerobic degradation of DDT)

• DDX/PCB ratio used to reveal local origin of DDX

• bulk DDT waste disposal peaked in 1950s (prior to regulation)

• contamination widespread across San Pedro Basin

• DDT transformed into less harmful compounds slowly

• evidence points toward bulk dumping

Blasius

• DDT and PCB analyzed in blubber of dead pinnipeds

• concentrations of DDT and PCB in sea lions and harbor seals in CA were highest among worldwide values

Dong et al.

• used satellite images to map oil slicks and sorces using microwave signals

• proportion of anthropogenic discharge was greater than natural seepages

  • contrast to previous estimate

• most oil slicks were close to shores

• many coincided with shipping routes

Hietbrink et al.

• nanoplastics measured from subtropical gyre to northern european shelf

• north atlantic receives plastic inputs from populated coasstlines

• water samples collected from 12 sites at mixed/surface layer, intermediate, and bottom layer

• mass spectrometry used to identify/quantify plastic polymer

• nanoplastics found throughout entire water column at all locations

  • mixed layer concentration had highest concentrations, bottom layer had lowest

  • largest concentrations near european continent

• found PET, PS, and PVC

• nanoplastics can be transported across large ocean distances

• nanoplastics boken down by UV sunlght and mechanical forces and bioaccumulated by microbs

• nanoplastics major component of ocean’s plastic composition

Hutchins

• tests for microbial adaptation and acclimation of thermal pollution and nutrient depletion

• warming and nutrient limitation affects responses of biogeochemically critical marine primary producers

• nutrient limitation being changed by warming effects phytoplankton optimum growth temps and efficiency

  • reflected by global poleward shift in phytoplankton if warming continues

Wang et al.

• antartctic mass increased between 2021 and 2023 in queen mary land and wilkes land (east antarctica)

• produced temporary slowdown in total antarctic mass loss due to global warming

• hypothesized that tropical warm-pool generated more moisture (snowfall) in this region (rossby-wave train)

• satellites were used to estimate changes in antarctice mass through gravitational field

  • measured precipitation, circulation, and ice records

• rossby-wave proved north-south pressure dipole moving moist air from indian ocean to east antarctica

• tropical warm-pool events recur approximately 1/decade