Flashcards
BIOL 276 Part 2
Cards in this deck (68)
- 1What is the difference between renewable resources and mining?The rate of regeneration must be greater than the rate of harvest, otherwise it is mining.
- 2What is more important to protect: a resource itself or the system that produces it?The system.
- 3What does the hydrological cycle consist of?Atmospheric circulation, Hadley cells, Earth rotation, etc.
- 4How does marine water move inland?Via atmospheric water vapour, which is then condensed into precipitation, which results in:
1. Runoff, such as returning to the ocean via rivers.
2. Infiltration, such as entering into groundwater aquifer pools.
3. Evaporation, such as transpiration from the soil to the atmosphere. - 5Why are most cities developed near large local water masses?1. Role of transportation and communication.
2. Resource supply, such as a habitat for food species.
3. Non-consumptive uses for industry, such as heating and cooling.
4. Consumptive uses for agriculture, irrigation, and domestic water use, such as drinking.
5. Waste disposal systems. - 6What effect does water solubility have on pollution?It results in the mass transport of pollutants via the hydrological cycle.
- 7What are Canada's consumptive and non-consumptive uses of water?Non-consumptive: power cooling, hydroelectric dams, municipal use, household use.
Consumptive: mining, agricultural use, ingestion. - 8How do humans manage water treatment?1. Water from rivers, lakes, or reserves is piped out of the surface source into a treatment plant.
2. Cl is added to kill bacteria, and Al is added to coagulate dissolved organic matter.
3. Water is filtered through sand.
4. Chemistry and pH levels are adjusted to make it more palatable.
5. Distributed through subterranean pipe network to processing centres, industrial for grey water and septic for waste.
6. Nutrients, organic matter, and biological pollution are removed.
7. Released to new location in hydrosphere. - 9How are new wastewater treatment plants more effective?They can collect multiple other substances such as methane or nutrients while simultaneously cycling water.
- 10What are some drawbacks of wastewater treatment plants?1. Issues can occur with pipes such as bacteria buildup or leaks.
2. Goal is to return to same water quality as source, but this is rarely done due to expenses.
3. Difficult to remove all concentrated material since separate treatments are needed for each different substance. - 11Why is groundwater a non-renewable resource?Fills naturally through slow seepage downward of mountains, replenished by snow melt at 1 mm a year, but extracted at 1000 mm a year. 50 year expected lifespan. More economically sound to let it run dry than to consider alternatives.
- 12What does hydroelectric energy depend on?A reliable water source.
- 13What are some concerns with alternative forms of energy?1. Hydroelectric: silt retention and biodiversity, such as the extinction of the Chinese river dolphin.
2. Geothermal: limited capacity.
3. Tidal: can only be used in specific areas.
4. Wind: biodiversity, such as mortality rates in birds and bats. - 14How is solar polar formed?Electricity generated by a photovoltaic effect, photons excite electrons into higher states of energy. Currently on small, individual scales.
- 15What are alternative forms of energy?1. Hydroelectric.
2. Solar.
3. Geothermal.
4. Tidal.
5. Wind. - 16What is an environmental stressor?A factor that can constrain productivity, reproductive success, and ecological development. Can be natural, such as competition, predation, or disease; or unnatural, such as pollution or habitat destruction.
- 17What are the three types of environmental stressors?1. Disturbances: intense and short-lived, substantial and sudden with large magnitude of impact, such as clear cutting or volcanic activity.
2. Natural constraints: slow, gradual changes that place an organism at the edge of tolerance, such as burrowing owls moving from Mexico to Saskatchewan.
3. Pollutants and contaminants: no natural source, entirely human in origin, cause change in environments beyond scope of natural variation, such as lake eutrophication. - 18Which two types of affects can stressors have?1. Acute: cause immediate effects.
2. Chronic: accumulate over longer periods of time. - 19What is the difference between exposure, response, and damage?1. Exposure: the interaction between an organism and a stressor.
2. Response: a biological or ecological effect provoked by intense levels of exposure.
3. Damage: unacceptable levels of degradation from response. - 20What do responses depend upon?1. Cumulative dose.
2. Rate of exposure. - 21What are some examples of responses?Increased death rates, decreased species diversity, biogeochemical disruption, negative net production, shift in dominant species, selection for stress-tolerant genotypes, loss of top predators, and disruption of ecosystem services.
- 22What are the two types of disturbances?1. Community-replacing: reversion to primary or secondary succession.
2. Microdisturbances: small and local scale disturbances. - 23What is pollution?Exposure to chemicals or energy at an intensity that exceeds tolerance. Can result in toxic responses, such as poisoning. Toxic algal blooms, insect outbreaks, and metal-rich soils all occur naturally but are exacerbated by humans.
- 24What are the three fields of pollution studies?1. Toxicology: the study of toxic substances or poisons, may have harmful immediate or long-term effects on the environment, primarily physiologists and chemists.
2. Environmental toxicology: environmental factors that influence exposure rates including pathways and transportation, transformation into other substances, and quantification of sinks.
3. Ecotoxicology: studies direct and indirect poisonous effects of chemicals, changes in structure, and functioning of ecosystems. - 25What is toxicity in terms of biological sensitivity?When a compound supply rate exceeds the ability of the organism to repair or detoxify.
- 26What is biological sensitivity?LD50 is a dose that kills half the population of experimental organisms, levels can be compared between species, sex, and route of exposure. Effects can be acute or chronic. Organismal differences and range of responses dependent on excretion, metabolism, and physiology. The dose determines the poison.
- 27What are indirect effects?Negative effects on non-target organisms, such as birds relying on insects killed by pesticides.
- 28What are the four steps of environmental risk assessment?1. Hazard assessment.
2. Dose-response relationships.
3. Exposure assessment.
4. Risk characterization. - 29What is hazard assessment, the first step of environmental risk assessment?The source of the problem is determined, possible carcinogens, possible causal factors. Historical data is assessed for possible cause-effect relationships. Basis for evaluation of toxicity is identified. Epidemiological studies and animal testing are often used.
- 30What are dose-response relationships, the second step of environmental risk assessment?Move from LD50 to ED50, the effective dose at which 50% of the population shows a response, and rank them. Small is bad, because the lower the dose, the more effective the chemical.
- 31What is exposure assessment, the third step of environmental risk assessment?The likelihood of exposure. Identify possible pathways and define biogeochemical cycling.
- 32What is risk characterization, the fourth step of environmental risk assessment?Characterizes risk and associated uncertainties, conduct series of cost-balance analyses.
1. Cost of action.
2. Risk-benefit analysis.
3. Public preference. - 33What is the precautionary principle?When an activity raises possible threats, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. Pushbacks to this principle are always jobs and the economy.
- 34What is air pollution?A change in the prevailing composition of the atmosphere that directly affects biogeochemical cycling or ecological systems.
- 35Which elements make up atmospheric composition?N2, O2, Ar, CO2, H2O, and 40 trace gases.
- 36What are aerosols?Fine, microscopic liquids and particles dissolved in the atmosphere, such as pollen, microbes, and virus particles.
- 37What are cleansers?Substances which naturally remove pollutants from the atmosphere, usually oxidants.
- 38How do cleansers work?UV radiation broken into O2 and a free atom O. Free O reacts with water to produce hydroxy ion, which cleans most atmospheric pollutants. Pollutants accumulate when cleansers are overwhelmed, results in smog.
- 39What are the two types of smog?1. Industrial: coal-fired energy releases atmospheric particles which quench cleansers and let pollutants accumulate; Need damp conditions and high particle load.
2. Photochemical smog: byproduct of petroleum combustion, volatile organic carbon compounds, post-WWII. - 40What is thermal inversion?A warm inversion layer between two layers of cool air which traps pollutants.
- 41What are the types of air pollutants?1. Suspended particle matter: liquids, dusts, smoke, haze, soot. High surface area sticks to other pollutants, lung irritant.
2. Volatile organic compounds: evaporate into atmosphere, suppress cleansers.
3. Carbon monoxide: incomplete oxidation, replaces O2 in respiration, toxic.
4. Nitrogen oxides: become acid rain in excess, oxidized during combustion.
5. Sulfur oxides: directly toxic to many organisms.
6. Lead: gasoline additive until 1980s, caused brain damage in children.
7. Ozone: ground level, not stratospheric. Produced in photochemical smog.
8. Rare toxins: often radioactive. - 42What are primary and secondary air pollutants?Primary: direct result of combustion and evaporation, 1 through 6.
Secondary: indirect result of air pollution, 7 and 8. - 43What is acid precipitation?Fossil fuel combustion produces NOX and SOX, oxidized forms of N and S. Interact with water vapour and hydroxy cleansers. Normal rain is acidic at 5.6 pH, but contaminants can drop this to 4.5 pH due to strong acids decomposing completely into ions. Kills algae and invertebrates, impacts food web structure, lake productivity, and fish communities.
- 44How did Sudbury deal with H2SO4 production?1883: gold and other metals discovered.
1883-1930: region deforested to burn wood, remaining vegetation killed, erosion and loss of soil.
1930: smaller smoke stacks to dissipate SO2, results in H2SO4 production 100s of kilometres away.
1972: superstack built, wider and higher range of dispersion, accounts for 4% of total global SO2 emissions.
1980: electrostatic scrubbers installed remove SOX, but not NOX.
2017: Now down from 2.25 million to 0.25 million per year. - 45How do ozone holes form?Due to increased rate of O3 degradation, fridge gas when compressed into liquid and expanded into gas. Cl reservoirs stick to ice crystals and get concentrated all winter, formed by descending water at the poles. In spring, all of the Cl crystals melt and get dumped into the atmosphere en masse. CFCs have since been replaced with HFCs.
- 46What are RAGs?Radiatively active gases that retain energy before it is lost, some also stop it from entering the atmosphere entirely.
1. Carbon dioxide: 60% of all atmospheric heat retention, build up since the start of the industrial age, most important due to high concentration.
2. Methane: 15%, 4X more effective per molecule of CO2.
3. Ozone: 8%, mainly in stratosphere.
4. Nitrous oxide: 5%, 300X more effective per molecule of CO2.
5. Chlorofluorocarbons: 12%, 1400X more effective per molecule of CO2. - 47What are the reasons for the increase in CO2?1. The conversion of fossilized C to CO2 via combustion.
2. Reduction of CO2 surface sinks including oceans, soil, and forests via deforestation. - 48What are the consequences of atmospheric warming?1. Rises in sea levels due to melting of continental glaciers and oceanic thermal expansion.
2. Changes in thermohaline circulation. - 49What is the basic scientific consensus to date?Increase of greenhouse gases will reduce rate of heat loss and increase atmospheric temperature on Earth. Humans are a cause of increased greenhouse gases. Significant reductions will take decades and full recovery will take centuries.
- 50What are the methods of dealing with climate change?1. Cap greenhouse gas emissions by limiting fossil fuel use.
2. Encourage alternative energy sources.
3. Save carbon sinks by reducing rates of deforestation.
4. Government regulation to improve energy efficiency.
5. Impose taxes and penalties for CO2 use.
6. Reduce energy demand via social intiatives and decreasing population size. - 51What were the effects of the past summit meetings for climate change?1. 1992 Rio Earth Summit: hold greenhouse gases to 1990 levels by 2000. No incentives, no penalties. Failed.
2. 1997 Kyoto Protocol: reduce greenhouse gases to 1990 by 2012. 38 countries signed except for China and India, would still see a 30% increase. Canada pulled out in 2012.
3. 2009 Denmark COP: failed to replace Kyoto.
4. 2016 Paris COP: hold temperature increase to below 2° C. Increase adaptation without threatening food production. Finance low greenhouse gas technology and climate change resistance. Nationally-determined goals, but still only incentives and no penalties, so less effective.
5. 2017 Bonn COP: finalize details of Paris Accord, how to ensure changes will occur. - 52How are dams constructed?Terrestrial environment is flooded and plants are drowned. Inundation of soil increased methyl Hg contamination via bioaccumulation. Flow regimes are changed, peak of reservoirs reduced and spread out. Obstruction restricts movement of aquatic species. Decrease in biodiversity, loss of top predators, increase in greenhouse gas emissions from reservoirs since soil degradation of organic matter creates methane.
- 53What are the two types of water pollution?1. Point sources or discrete: a specific outpouring.
2. Nonpoint sources or diffused: general agriculture. - 54What are the different types of water pollution?1. Biological: introduction of non-native species into new habitats. Profound alteration on food webs and displace native species, such as zebra mussels.
2. Pathogen: bacteria and viruses from waste. Effect on water potability, such as salmonella.
3. Organic: strips oxygen from water which favours solution of toxic metals, constrains animal growth, causes shifts in community biogeochemistry composition.
4. Chemical: osmotic stress on invertebrates and fish, impairs aquatic ecosystem functioning, such as de-icing salt seeping to lake bottoms.
5. Sediment: erosion increases silt input in water bodies, smothers bottom plants and animals, reduces photosynthesis and covers habitats.
6. Nutrient: excess supply of P or N, unnatural increase in productivity, kills fish, changes in phytoplankton community composition, such as toxic algal blooms. - 55How can eutrophication be treated?1. Harvesting of aquatic weeds.
2. Artificial aeration or inserting bubbles in stagnant areas. - 56How is wastewater treated?1. Preliminary screening to remove objects collected in landfill.
2. Primary treatment to remove organic matter by sedimentation and flotation. Trying to decrease substrate and increase O2 in receiving waters. Sludge is collected and retained for later steps or fermented to remove metals and recycle as compost.
3. Secondary treatment uses microbes to remove dissolves organic matter. Strategies include an aeration tank or lagoon to increase O2 and a clarifier to remove bacteria.
4. Tertiary treatment precipitates nutrients with non-soluble lime, fire, and Al particulates.
5. Polishing step to disinfect and remove microbes via UV radiation. Can collect bacteria as fertilizer and capture methane as an energy source. - 57How is wastewater transformed at a molecular level?1. Convert organic matter N into NH3 via ammonification in an anaerobic environment.
2. Convert NH3 into NO3 nitrate via nitrification in an aerobic environment.
3. Convert NO3 into N2 via denitrification in a low O2 environment.
4. Harvest bacteria to capture N and P and use as fertilizer. - 58What are the types of acid precipitation?1. Wet deposition: acid rain.
2. Wet deposition: acid fog, lowest pH, can burn leaves and decreases plant production.
3. Dry deposition: NOX and SOX absorbed by plants and react with cellular H2O.
4. Modification by vegetation: through flow down stems or leaves, chemistry changes as it moves toward the soil. - 59What are the effects of acid precipitation?1. Thin or poorly developed soils can experience an increase in acidic pH levels.
2. Change in solubility of basic cations, Ca, Mg, and K can be lost from soil.
3. Increase in solubility of other metals, such as Al, Fe, and Mn.
4. Excess SO4 can produce H2SO4 later under extremely acidic conditions. - 60What are sustainable management practices for livestock?1. Select breeds for high yield.
2. Develop converted pastures to assure feed supply.
3. Supplement food with protein from fish, legumes, and minerals.
4. Medicines and antibiotics to maintain health and hormones to increase yield.
5. Remove natural predators and competition.
6. Basic human animal treatment. - 61What is the first category of environmental impacts of intensive agriculture?Declining fertility of soil ecosystem: erosion of topsoil, decrease in organic matter, increase in weeds. Harvest removes nutrients from soil, must add nutrients back to sustain productivity. Plants need to be fertilized at fixed N ratio, but hard to guess so overfertilization occurs. Loss of soil organic matter due to excess cultivation and tillage leading to erosion. Management strategies include no-tillage seeding and harvest, adding crop residues back to the soil, and adding organic-rich waste inputs like manure or compost. Soil compaction from heavy machinery and livestock at high densities eliminates air spaces and constrains root respiration. Adapt by decreasing livestock density and runs of heavy equipment and larger tires to spread weight. Without proper drainage, soils can become saline and decrease plant growth.
- 62What is the second category of environmental impacts of intensive agriculture?Pollution of adjacent ecosystems: ground and surface water very susceptible, naturally nutrient rich, excess productivity due to N and P, pesticides are soluble and run off into water. Atmosphere also polluted by excess nutrients, CO2 increase due to soil respiration, hot exposed soil increases microbes, CH4 production from livestock, incomplete denitrification. Waste management needs improvement, better storage, conversion back to fertilizer, results in decreased importation of N and P into lake drainage area.
- 63What is the third category of environmental impacts of intensive agriculture?Conversion of adjacent ecosystems: problem in developing countries since all available land has already been converted in industrial countries. 50% of wetlands are gone, 90% decrease in native prairie habitat. Conservation measures to reestablish these.
- 64What are the four signs the Green Revolution is over?1. Most potential has been achieved, a production plateau.
2. More irrigation and fertilizers, chronic water shortages and pollution.
3. Propagation of social injustice, high yields are expensive and small or poor farms cannot afford them.
4. Many important crops are not high yield, not all cultures embrace wheat, corn, etc. - 65Which factors lead to the pesticide treadmill?1. Resistance: strong selection in rapidly reproducing pests.
2. Resurgence: secondary outbreaks, simplification of food webs leads to previously suppressed species coming back at higher levels.
3. Human health effects: pesticides as immunosuppressants and carcinogens. - 66What are alternative methods of pest control?1. Cultural controls: change behaviours to reduce pest outbreaks or impacts, such as allowing grass to grow to outcompete weeds or planting natural insect repellant plant species.
2. Natural enemies: conserve predacious to control pests without harming non-target species, such as beetle introduced to combat purple loosestrife.
3. Genetic controls: genetic modifications made through selective breeding or biotechnology, such as increasing nicotine concentration which is a natural insecticide.
4. Genetic modification: altering DNA or genomes explicitly to increase pesticide resistance, such as bacterial genes added to crops to kill insects. - 67How is environmental policy developed?1. Recognition: some form of discovery by scientist, usually uptaken by not critically thinking media, low public awareness, investigation begins but is disorganized.
2. Formulation: increased political weight and opposition, more serious and organized, government seeks input to form policy, role of media changes and opposing views are treated equally despite merit, increased media and public interest, policy must be effective, efficient, and equitable.
3. Implementation: regulatory agencies involved, how to apply formal policy, political and capital costs now evident, little media coverage or public interest.
4. Control: problem not gone, just reduced, monitoring continues, no more interest. - 68How are sustainable environmental changes made?1. Environmental monitoring: evidenced-based decision making in the long term.
2. Environmental education and literacy: be well-informed, encourage and support reporting by media.
3. Societal participation: NGOs, advocacy groups, governmental organizations.
4. Environmental citizenship: reduce, reuse, recycle.
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- Biology Flashcards on BIOL 276 Part 2, created by Carlie Hinz on 13/12/2017.
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