Fish that are harvested, but which are not sold or kept for personal use, including economic and regulatory discards
Marine Protected Areas (MPA)
Areas where human activity has been placed under some restrictions
not necessarily off limits to all commercial use
Name 3 Aquaculture recommendations for fisheries sustainability
farming species lower on food web
improve feed management, efficiency
develop integrated fish farming systems
promote environmentally sound practices and resource management
Name 3 Negative impacts of aquaculture
destruction of mangrove forests, coastal wetlands
use of wild caught fish to stock operations (increases bycatch)
increased pressure on small ocean fish for fish meal (increases bycatch, depletes food source for wild fish)
transport of fish diseases, non-native fish to new waters
nutrient pollution of coastal waters
DDT
Persistant Organic Toxin
Persistent pollutants
Pollutants that remain in the environment for many years
heavy metals
persistent organic compounds
PCB
Persistant Organic Toxin
National Marine Fisheries Service (NOAA Fisheries)
science-based conservation and management, promotion of healthy ecosystems
Classifying an overfished fishery – 2 main components
fishing mortality rate (F)
stock biomass (B)
If F is > maximum fishing mortality threshold (MFMT)
the stock is being overfished
If B level has fallen below the minimum stock size threshold (MSST)
the stock is being overfished
Corrective measures to overfishing
Prohibit all harvest (i.e., all sources of fishing mortality) of the overfished stocks
Allow harvest in accordance with a rebuilding program
Benefits of Marine Reserves: Name 3
increases in the abundance, diversity and productivity of marine organisms
decreased mortality, decreased habitat destruction and to indirect ecosystem effects
reduce the probability of extinction for marine species resident within them
increased reserve size results in increased benefits, but small reserves beneficial, too
full protection is critical to achieve this full range of benefits
Ecological effects outside reserve boundaries
increase in size and abundance of exploited species in adjacent area
replenishment of regional population by larval export
Ecological effects of reserve networks
greater protection for marine communities than a single reserve; buffers against vagaries of environmental differences
provide a stable platform for the long-term persistence of marine communities when networks encompass large areas
Coral Bleaching
zooxanthellae expelled
stress due to:
Temperature
light
nutrients
pH
Risks to coral reefs: Name 3
Poaching
Sedimentation
Pollution
Coastal development
Overfishing
Water quality objectives for the Chesapeake Bay TMDL include criteria for:
E. Dissolved oxygen, chlorophyll a, and water clarity
A watershed approach to assessment and management of pollution sources is:
C. Total Maximum Daily Load
Nonpersistent pollutants – 2 general categories
Biodegradable
Decompose due to inorganic chemical or physical reactions
Biodegradable pollutants
changed to non-toxic form by an organism (usually decomposers such as bacteria or fungi)
Decomposition due to inorganic chemical or physical reactions:
Sunlight/UV radiation
Chemical oxidation
Reaction with water
Reaction with atmosphere
Dichlorodiphenyltrichloroethan (DDT)
Highly effective pesticide
Persistent organic pollutant
Low solubility in water
Highly lipophilic - accumulates in fat
Bioaccumulates and biomagnifies in food webs
DDT world use
first used in WWII for malaria, after the war for agricultural pests
banned in most western countries
usage in the world today is roughly the same as it was prior to the ban by most of the Western countries
DDT – Health effects
chemically similar enough to estrogens to trigger hormonal responses in animals
exposure occurs from inhalation, skin contact and ingestion of contaminated food
can cross the placenta
associated with increased risk of breast cancer
Polychlorinated Biphenyls (PCBs)
no natural sources
Used as coolants and lubricants in electrical equipment
Environmentally stable
Accumulate in sediments and animal tissues
Manufacture in U.S. banned in 1977
PCBs – Health effects
humans at risk of exposure through air, water, food
possible carcinogen
Developmental effects
Reproductive effects
Neurobehavioral effects
Acne-like skin conditions
Immune system disorders
Endocrine Active Compounds (EACs)
can disrupt animal reproduction and development
biogenic hormones created in the body
synthetic hormones (such as those manufactured for birth control or menopausal supplement)
industrial/commercial compounds which can have some hormonal function (such as alkylphenols, pesticides, pharmaceuticals, and phthalates)
Sources of EACs
Many fossil fuel-derived plastics in use
Pesticides
Pharmaceuticals
EACs and Human Health
Can cause problems at extremely low doses
Can cause irreversible, lifetime disorders
May contribute to increased prevalence of many human disorders
Atrazine
Crop protection: Corn, sorghum, sugar cane, turf
Potential human health risk (endocrine disruptor)
Regularly found in ground and drinking water, as well as in sea water and the ice of remote areas
One of the world’s most heavily applied herbicides
European Union (EU) banned in 2003
Bisphenol A (BPA)
Present in many hard plastic bottles and metal-based food and beverage cans since the 1960s
Recently recognized as a potential health hazard
doesn’t readily biodegrade
known to have leaching capabilities (leaches from plastic drinking bottles)
Bisphenol A (BPA)
BPA in Mice (2)
feminized behaviors in adult males exposed during development
low-level, chronic exposure induces insulin resistance in adults. experimental link bet
Triclosan
antibacterial properties
Triclosan can be found in:
detergents, dish-washing liquids, soapsdeodorants, cosmetics, lotionsanti-microbial creamsToothpastesvarious plastics and textileshousehold items like toys, mattresses, toilet fixtures, clothing, furniture fabric, and paints
Triclosan Health Risks
similar structure to dioxins and PCBs
EPA gives triclosan high scores both as a human health risk and as an environmental risk, but human health effects not yet demonstrated
expected to be immobile in soil, water
Hg human health effects
Methylmercury most toxic, though not linked to cancer
For fetuses, infants, and children, the primary health effect of methylmercury is impaired neurological development
Impairment of peripheral vision
“pins and needles” sensation in hands, feet, mouth area
Impairment of speech, hearing, walking, and muscle weakness
Hg in aquatic food webs
In water, greater Hg mobility is associated with lower pH and high DOC, thus making it more likely to enter the food chain
MeHg in bacteria is consumed directly in sediments to enter food web, or released as MeHg and adsorbed onto phytoplankton, which then enter the food web.
Hg control in environment
EPA Clean Air Mercury Rule (CAMR - 2005) focuses on cap-and-trade program project to reduce Hg emissions from power plants by 70% by 2025
Toxicity of Metals
Many metals inhibit microbial decomposition processes – litter decomposition, methanogenesis, acidogenesis, nitrogen transformations, biomass generation, and general enzymatic activity
Examples of non-persistent pollutants that decompose due to inorganic chemical or physical reactions
Carbon monoxide
ammonia
Examples of Biodegradable Non-persistent Pollutants
Organophosphates
pesticides
Total Maximum Daily Load (TMDL)
Maximum pollutant load to a waterbody that still meets water quality standards
Allocation of maximum load (3)
Point sources (PS)
Non-point sources (NPS)
Margin of safety (MOS)
Point sources (PS)
Single identifiable localized source
Enters in a well-defined conveyance, such as a discharge pipe or channel
All point sources are under regulatory control and must operate under a discharge permit
Non-point sources (NPS)
Enters from a diffuse source, such as runoff or atmospheric deposition
Little regulatory control over non-point sources
Sum of all waste load allocations to point sources
Sum of all waste load allocations to nonpoint sources
Waste load allocation + Load allocations + Margin of Safety
Margin of Safety
Examples of Point Sources
Stormwater runoff from large urban areas
Runoff from Concentrated Animal Feeding Operations (CAFOs)
(In some rare cases) Agricultural runoff from commercial nurseries
Steps in the TMDL Process (5)
Define water quality objectives
Relate pollution load to objectives
Estimate existing pollution sources
Evaluate/select control alternatives
Allocate total pollution load among sources
Water Quality Standards
Numeric: Quantitative definition of the permissible level of a specific pollutant
Qualitative descriptions of the conditions of the water body
Watershed models
Compute export of water and pollutants from the land surface (and ground water) to the receiving water body
Computes freshwater inflows and loads of nitrogen, phosphorus and sediment to bay
Non-point sources: Best Management Practices (BMPs)
Site-specific
Storm-specific
Maintenance-specific
Point sources: Wastewater treatment plants (WWTPs)
generally well-developed and have known degrees of effectiveness
TMDL Pitfalls and Uncertainties
No numeric water quality standards exist for nuisance plant growth
Insufficient data to develop reliable models
Difficult to monitor existing loads
Lack of knowledge on effectiveness of BMPs for non-point sources
Non-technical issues: Margin of safety, Cost-effectiveness, Social, Political issues
North Buffalo Creek “Impaired” Waters
Not safe for recreation
Fecal coliform standard exceeded
Recreational users at elevated risk of contracting water borne diseases, Typhoid fever, viral and bacterial gastroenteritis, hepatitis A
Not supporting aquatic life (biological impairment)
Buffalo Creek Loads from Non-point Sources
Pets
Sanitary sewer exfiltration (leaks)
Sewer system overflows (SSOs)
Septic systems
Wildlife
Unidentified, non-stormwater related sources(a.k.a. dry weather flow sources, illicit connections)
Direct damage to plants (especially due to acid fog)- erodes waxy coatings on leaves, leaches nutrients from leaves, harms buds
Large areas of forest are dead or dying in sensitive areas
Estimated cost to forests - $5 billion / year
Acid Damage to Fresh Water Systems
Surface waters have lost alkalinity (buffering capacity)
Fishes killed – acid mobilizes aluminum from watershed, lake sediments, or stream bed
Aluminum irritates fish gills, causing excess mucus production which interferes with O2 uptake – fish suffocate
Other organisms damaged at lower pH than fish (crawfish, snails, some insects)
Changes in algal and animal species
Acid Damage to Streams
Event based – pH drops during rainfall and snowmelt events
Kills fish
Many stream insects sensitive – changes species
Streams drain into lakes, acidifying them
SO2, NOx emmissions are...
declining
Coastal and Oceanic Acidification
NO3 deposition to estuaries and coastal waters contributes to eutrophication, harmful algal blooms, low O2, fish and shellfish kills
Current Status of Acidification
SO2 and NOx emissions are declining, and the allowance bank has declined.
Acid deposition has decreasedWater quality and forest recovery have been marginal (and are very region specific).
Air quality has not improved measurably
Urban impacts on biodiversity include
A. Decrease in mammal diversity
An effect of urbanization on groundwater is:
E. a and c only
Which of the following is important in the epidemiology of a species invasion?
E. All of the above
Mechanisms by which invasive species cause harm include:
E. a and c only
Marshes
wetlands that are frequently or continually inundated with water, characterized by emergent soft-stemmed vegetation adapted to saturated soil conditions.
Nontidal Marshes
Occur along streams in poorly drained depressions, and boundaries of lakes, ponds, and rivers.
Water levels vary from a few inches to two or three feet.
Some periodically dry out completely.
Wet meadows
Vernal pools
Prairie potholes
Playa lakes
Prarie Potholes
those of Canada, Minnesota and the Dakotas were formed by glaciers scraping over the landscape during the Pleistocene
Vernal Pools
are seasonal depressional wetlands that occur especially in Mediterranean climate conditions of the West Coast.
Covered by shallow water for variable periods from winter to spring; may be completely dry for most of the summer and fall.
Playa Lakes
Round hollows in the ground in the Southern High Plains of US.
Ephemeral, most fill with water only after spring rainstorms.
Some are saltwater, filled by groundwater which evaporates to leave salt.
Thought to be carved by wind or formed by land subsidence (sinkholes).
Swamp
any wetland dominated by woody plants
Shrub Swamps
Mangrove swamps are important tropical coastal ecosystems
Bog
Characterized by spongy peat deposits, a thick carpet of sphagnum moss, and acidic water
Pocasins
bogs densely vegetated with trees and shrubs. They are subjected to fire about every 10 to 30 years – Carolina Bay Lakes are pocosins
Fens
similar to bogs, and also are peatlands, but they are fed by groundwater and are not as acidic as bogs
Mangrove Swamps
Habitat for juvenile fishand shellfish-
Filter sediment that damages reefs and seagrass beds-