Untitled Flashcards Set

ENV-1600 Final exam study guide

1.     Advantages of Living in Water

Physical support from water buoyancy, fairly constant temperature, nourishment from dissolved nutrients, water availability, less exposure to harmful UV radiation

2.     Disadvanatages of Living in Water

Cannot tolerate a wide temperature range. Exposure to dissolved pollutants, fluctuating population size for many species, many aquatic offspring separated from parents by dispersion

3.     What is one super important substance that is rarely if ever limiting on land but can be limiting in water?

Phosphorus

4.     What is a euphotic zone?

Upper layer of a body of water, such as an ocean or lake, where enough sunlight penetrates for photosynthesis to occur. This zone typically extend from the surface down to a depth where light levels are too low for most plants and algae to grow. Nutrient levels are low except around upwellings, and levels of dissolved oxygen are high. Large, fast swimming predatory fish such as sharks populate this zone.

5.     Where would we find the pelagic zone?

refers to the open water area of an ocean or large bodies of water, away from the shore and seafloor. It is divided into different layers based on depth

6.     Where would we find the benthic zone?

The bottom layer of a body of water. Refers to the seafloor. This zone includes the area from the shore (intertidal zone) down to the deepest parts of the ocean floor.

7.     What is an estuary?

A partially enclosed area of coastal water where sea water mixes with fresh water and nutrients from rivers, streams, and runoff from land. Typically shallow, nutrient-rich environments that support a wide variety of plants and animals.

8.     Why are coral reefs important?

Highly productive and diverse ecosystem. Remove CO2 from the atmosphere. Protect shorelines from erosions. Support fishing, tourism.

9.     Benefits of coral reefs

Support biodiversity, protect coastlines from erosions and storms, boosting local economies through tourism and fishing, offers medicinal resources for drug development

10.  What is causing ocean acidification?

Occurs when excess CO2 is absorbed by seawater, forming carbonic acid, which lowers pH making it more acidic. This harms marine life, especially shell-forming organisms like corals and mollusks, and can affect fish and other marine species

11.  What is the bicarbonate buffer system?

Helps maintain stable pH by balancing carbonic acid and bicarbonate ions, which absorb or release hydrogen ions to prevent drastic changes in acidity. When Co2 is added, the system shifts to produce more hydrogen ions, making the water more acidic. When Co2 is removed, the system shifts to reduce hydrogen ions, making the water more basic (alkaline).

12.  What happens to ocean chemistry and the calcium carbonate shells of marine organisms when we add more carbon dioxide to the atmosphere?

When we add more carbon dioxide to the atmosphere, the ocean absorbs some of it, forming carbonic acid. This lowers the oceans pH, making it more acidic. The increased acidity reduces the availability of calcium carbonate, which marine organisms like corals, mollusks, and some plankton need to form their shells and skeleton. As a result these organisms struggle to build and maintain their shells, threatening marine ecosystems

13.  List 4 human impacts on the world’s marine ecosystems

(1)  Half of coastal wetlands lost to agriculture and urban development. (2) Over one-third of mangrove forests lost since 1980 to agriculture, development, and aquaculture shrimp farms. (3) About 10% of the world’s beaches eroding because of coastal development and rising sea level. (4) About 75% of the world’s coral reefs threatened.

14.  What kind of habitat would we find in the littoral zone and how does it differ from the limnetic zone or pelagic zone?

The littoral zone is the shallow, sunlit area near the shore of a body of water, where plants like bulrushes, cattails, and water lilies thrive. It has high biological diversity and plenty of nutrients from bottom sediments. It differs from the limnetic zone as this zone is the open water further from shore, where sunlight still reaches and supports photosynthesis. It is the primary area for producers, like algae, which supply oxygen and food for the lake’s ecosystem. The littoral zone is more plant-dense and close to the shore, while the limnetic zone is the deeper, open water way from the shore.

15.  Describe how lakes (that are deep enough) stratify in the summer

in the summer, most lakes are affected by thermal stratification. The warm surface layer, called the epilimnion, is heated by the sun and mixed by wind and waves, creating well-oxygenated water. Beneath it lies the thermocline, where temperature drops rapidly, acting as a barrier that prevents mixing of nutrients, oxygen, and organisms between the warmer upper layer, and the colder deeper layer. The colder, denser hypolimnion below has lower oxygen levels because it is isolated from the surface by the thermal stratification of the lake

16.  In a productive (somewhat eutrophic lake) what tends to happen to the concentration of dissolved oxygen in the water as you get close to the sediments? Why?

Dissolved oxygen tends to decrease as you get close to the sediments. This happens because the high levels of nutrients in the water lead to increased decomposition at the lake’s bottom. As decomposers break down organic material, they consume oxygen, which depletes the oxygen levels in the deeper water.

17.  What is a watershed?

An area of land that delivers water (sediment and dissolved substances) to a stream/river/lake.

18.  Why do rivers tend to become more nutrient rich the further removed they are from their source?

They collect nutrients from various sources along their course. As the river flows, it picks up organic matter, soil, and nutrients like nitrogen and phosphorus from surrounding land, including agricultural runoff, urban areas, and wildlife.

19.  What kind of “ecosystem services” do wetlands provide?

They absorb pollutants, improve water quality, slow soil erosion, provide flood control, and store greenhouse gases they also yield recreational benefits, economic spinoffs (such as wild rice, fish, fur, cranberries, and peat).

20.  What happened to most of the wetlands in the prarie provinces? Why?

Most have been drained or converted for agricultural use. occurred primarily for farming and urban development to create more land and accommodate growing human populations. Drainage of wetlands helped improve soil for crops like wheat.

21.  How does the amount of water on the planet moderate climate?

By absorbing and releasing heat. Water has a high heat capacity, meaning it can absorb large amounts of heat without significantly changing temperature. This helps stabilize temperatures, particularly in oceans.

22.  Of the total amount of water on the planet, about how much is fresh?

0.014%  

23.  What state is most of the world’s freshwater in?

about 97.4% of the worlds total volume of water is found in the ocean and saline lakes and is too salty for drinking, irrigation or industry.

24.  What is groundwater?

Water that exists beneath the earth’s surface, filling the spaces between particles and rocks. It is found in the zone of saturation, where the soil is completely saturated with water, and the top of this layer is called the water table.

25.  How much groundwater is there in comparison to the amount of freshwater in lakes and streams?

Ground water found within 1 km of the earth’s surface contains more than 100 times all the water found in the world’s rivers, streams and freshwater lakes

26.  What is an aquifer?

A layer of rock, sand, or gravel underground that holds water. It acts like a natural water storage system, where water can flow through and be stored for long periods.

27.  How are aquifer’s recharged?

By precipitation and percolation and by nearby streams

28.  What is subsidence?

When too much water is remove the sand and rock in the aquifer can collapse causing the land above it to sink

29.  What casues subsidence?

Caused by removal of underground water, oil, or gas. When large amounts of groundwater are pumped out of an aquifer, the ground can collapse or compact, leading to a drop in elevation.

30.  Globally, how much of the world’s water goes to agriculture, industry, and domestic use?

70% Agriculture

19% industrial

11% domestic

31.  Even though we are getting better, globally there are still one in ____ people who lack access to safe, clean water.

1 in 11

32.  There are over ___ people who lack access to improved sanitation.

2 billion

33.  What happened to the Aral Sea? How has this affected the surrounding area and its people?

The Aral sea has largely dried up due to the diversion of rivers that fed it for irrigation purposes, primarily for cotton farming. This caused the sea to shrink dramatically, leading to loss of fishing industries, increased salinity, and dust storms. The surrounding area suffered from environmental degradation, poorer air quality, and health issues.

34.  Why does the Colorado River often not reach the ocean in the dry season?

Because of human withdrawals of water for irrigation and industry.

35.  How can we increase our access to freshwater?

Building dams and reservoirs to store runoff for release as needed. Bring in surface water from another area. Withdraw groundwater and convert salt water to fresh water (desalination), reducing water waste and importing food to reduce water use in growing crops and raising livestock.

36.  Disadvantages/environmental/social effects of creating dams and reservoirs

Flooded land destroys forests or cropland and displaces people. Large losses of water through evaporation. Deprives downstream cropland and estuaries of nutrient-rich silt. Risk of failure and devasting downstream flooding. Disrupts migration and spawning of some fish.

37.  One of the best ways to gain access to more water is to conserve it – name some ways that water is currently wasted and what we can do to improve it

Water is wasted by leaky toilets and taps – repair leaks and invest in modern, efficient water systems

Over-irrigation in agriculture- excessive watering leads to runoff and waste

Solution: use drip irrigation and soil moisture sensors to optimize water use

Excessive lawn watering

Solution: replace lawns with drought-tolerant plants or use smart irrigation systems that adjust based on weather conditions

38.  While Canada has ~ 20% of the world’s total freshwater resources we only have about ____ of the world’s renewable supply?  What is considered renewable supply?

6.5% of the global renewable supply. Renewable supply refers to the portion of freshwater that is replenished through processes like precipitation and surface runoff, which is available for use on an ongoing basis.

39.  In Canada, nearly all of our water drains in this direction?

Northward into the Arctic Ocean and Hudson Bay

40.  How is the price of water that a country pays related to the per capita water consumption of their citizens?

The price of water in a country is negatively correlated with per capita water consumption. Countries where water is inexpensive, people tend to consume more water. When water is cheap, there is less incentive for people to consume it, leading to higher consumption. In countries where water is more expensive, people are more likely to conserve it due to high costs.

41.  How do Canadians use water at home and how much do they consume on average per capita daily?

65% from toilets/showers, 20% laundry, kitchen 10%, cleaning 5%. Consume about 251 L/person/day.

42.  Explain what a water footprint is

The amount of water that is used in everything you do. Includes not only the water used at home, but the water that goes into making everything you eat, use, and wear.

43.  why is the water footprint much larger than the amount of water used in the home daily?

Because it includes all the water used to produce goods and services. Includes water for food production, manufacturing products, and generating energy, and water used in the production of imported goods.

44.  Why is pollution a factor in calculating the water footprint?

Because grey water represents the amount of water required to dilute and assimilate pollutants in water to maintain water quality standards.

45.  Where does Winnipeg get its drinking water from and how does that water get here?

From Shoal lake. It gets here by gravity through an aqueduct in the city where it gets treated.

46.  After we flush our toilet or do our laundry – where does our water go? 

Lake Winnipeg. From there it heads north down the Nelson river to Hudson bay and the Atlantic and Arctic Oceans

47.  If we look at the water footprint of various food items, we find that this food group (____) has the smallest water footprint, while this food group has the highest (______)

Fruits and vegetables- smallest

Meat and dairy- highest

48.  How could you reduce the amount of water you consume in your own home?  List 8 ways

Install a low flow or dual flush toilet, time your showers, check toilet for leaks, only use a small amount of soapy water for dishes, only do full loads of dishes in dishwasher, eat less red meat, eat more vegetables, don’t waste food.

49.  Does light penetrate deeper in an oligotrophic or a eutrophic lake?

Oligotrophic lakes are clear, with low nutrient levels, allowing more sunlight to reach greater depths. Eutrophic lakes have high nutrient levels, leading to more algae growth, which reduced water clarity and limits light penetration.

50.  When we clear cut a forest, how might this affect adjacent aquatic systems within the watershed?

Can affect adjacent aquatic systems by increasing erosion, which leads to sediment runoff, raising water temperatures, and causing nutrient runoff that can result in algae blooms. Can also disrupt natural water flow leading to extreme flooding or droughts.

51.  What is eutrophication?

The natural nutrient enrichment of lakes over time, mostly from runoff of plant nutrients they receive from surrounding land. As lakes age, they naturally become more nutrient rich over time.

52.  What is cultural eutrophication?

The acceleration of eutrophication by human activities that add plant nutrients to a lake

53.  What does Liebig’s Law of the Minimum tell us about the growth of biological organisms?

An organism’s growth is limited by the smallest amount of an essential resource. Even if everything else is abundant, if one thing is in short supply, it will limit growth. Example; a plant cant grow well if it is missing one important nutrient, even if it has enough water and sunlight.

54.  Which nutrient tends to be most limiting for phytoplankton in freshwater aquatic ecosystems?

Phosphorous.

55.  Name two unique features of Lake Winnipeg that may reduce the negative effects of nutrients on the system

relatively shallow and very large, so a lot of waves/mixing  = better aeration which reduces dead zones due to a lack of dissolved oxygen and a relatively low residence time

56.  How many outlets does Lake Winnipeg have?

Only one- the nelson river

57.  What was the effect of Lake Winnipeg Regulation on water levels within the lake?

Reduces peak and increases minimal water levels within the lake.

58.  What 2 key experiments at the Experimental Lakes Area did they do to determine that it is phosphorus that is the key to solving most freshwater eutrophication problems?  Why can’t removing nitrogen solve the problem?

Lake 227 (phosphorus addition experiment):  researchers added phosphorus to lake 227. The result was a significant increase in algal blooms, demonstrating that phosphorus is the primary limiting nutrient in freshwater lakes and that its addition directly causes eutrophication . Lake 226 (phosphorus removal experiment): phosphorus was removed from lake 226 by using chemical treatments to reduce phosphorus levels. As a result, algae growth dramatically decreased, further confirming that phosphorus is the key nutrient driving eutrophication in freshwater lakes. Nitrogen cant solve the problem, because phosphorus is often the limiting nutrient in freshwater lakes. Even if nitrogen us removed, algae will still grow if there is enough phosphorus.

59.  Name 5 (or more) factors that contribute to the cultural eutrophication of Lake Winnipeg.

Increased runoff from city surfaces and inputs directly from sewage treatment plants without proper tertiary treatment to effectively reduce nutrient levels, draining of the majority of wetlands in the Red River Valley, use of fertilizers and spreading of manure on fields, increased runoff from fields and possibly through tile drainage systems, poor health of Netley-Libau marh, climate change.

60.  Name 3 reasons for the poor condition of the Netley Libau Marsh at the south end of Lake Winnipeg.

The netley cut- caused significant erosion and altered water flow, allowing 1/3 od the red river to flow through the marsh.

Introduction of common carp- their foraging behaviour uproots submerged plants, increases water turbidity, and impedes the growth of native vegetation.

Reduce drawdown from hydro

61.  What can certain species of cyanobacteria do that most other phytoplanktonic organisms cannot, (with respect to nutrients)? 

Some can perform nitrogen fixation. This allows cyanobacteria to convert atmospheric nitrogen to a usable form, like ammonia, which they can use for growth. This enables them to thrive in environments with low levels of nitrogen.

62.  What kind of effects might be expected from very large algal blooms on lakes?

Be unsightly and produce toxins, reduce usability of water, reduce property values, cause anoxic conditions and potentially fish kills.

63.  List a few steps we could take to help reduce the eutrophication problem in Lake Winnipeg?

Keep water on the land, conserve the boreal forest, setting the standard for wastewater treatment, monitoring our waterways, managing our shorelines

64.  What makes species invasive?

Out-compete native species for resources, tend to have 0 or few natural predators, can usually multiply quickly, can have economic, social, environmental and human health implications.

65.  What is the primary way that aquatic invasive species are spread to new waterways?

Boating, and fishing, interconnected waterways, un-cleaned fishing equipment and gear, release of live bait and bait water.

66.  Name 3 aquatic invasive species in Manitoba

Common carp, spiny waterflea, zebra mussels

67.  Zebra mussels are different from all of our native mussels because they attach to hard surfaces using _____  _____.

Byssal threads

68.  One female zebra mussel can produce up to _____  eggs per year.

1 million

69.  Zebra mussel eggs hatch into free-floating _____ larvae that are microscopic.

Veliger

70.  How long are they in this free-floating larval stage until they attach to a substrate?

2-3 weeks, veligers start to form shell, attach to substrate and grow.

71.  While we don’t know exactly what will happen in Lake Winnipeg, list 6 impacts that zebra mussels have had on other lakes?

1.     Increased water clarity and aquatic vegetation growth

2.     Increase in toxic algal blooms

3.     Altered aquatic food webs

4.     Decrease in lake whitefish and walleye populations

5.     Reduce recreational potential

6.     Clogged intake structures

72.  When and where in Canada (which lake) were zebra mussels first discovered?

1986 in Lake Erie

73.  What three things do you have to do with a boat or other watercraft or water toys etc. to prevent transfer of zebra mussels from one location to another?

Clean, drain and dry

74.  Name 3 ways mercury can become elevated in bodies of water

Burning of coal, flooded land, metal refining (especially gold)

75.  The conversion of elemental mercury to ______ mercury results in it becoming much more bioavailable and bioaccumulating in organisms and biomagnifying up the food. chain.

Methyl

76.  Define bioaccumulation

The buildup of toxic substances in an organism’s body over time. These substances, like mercury, are absorbed faster than the organism can get rid of them, leading to higher concentrations in its tissues.

77.  Define biomagnification

Animals higher in the food chain wil have higher concentrations than those lower in the foodchain

78.  There are two fish of the exact same species, but one is twice the size of the other – which will have more mercury, the small or large fish?

The larger fish will have more mercury. Mercury accumulates over time, so a larger fish, being older, has had more time to accumulate mercury in its tissues compared to a smaller, younger fish. Even though they are the same species, the larger fish has likely been exposed to mercury for a longer period, resulting in a higher concentration.

79.  The concentration of mercury would be (higher or lower) in zooplankton than it would be pike (fish).

It would be lower. Mercury biomagnifies up the food chain, meaning that as predators consume prey, the concentrations of mercury increase. Zooplankton, being at a lower trophic level, have lower mercury concentrations compared to pike, which are higher up the food chain and accumulate more mercury over time.

80.  The amount of mercury released when land is flooded in the creation of reservoirs is dependent on the amount of land flooded and its_______ ________ content. 

Organic matter

81.  It takes about 10 years for mercury concentrations in fish to peak after flooding and between 10-20 years or even longer after that for mercury concentrations in fish to drop down to levels experienced prior to flooding. 

Correct

82.  How much mercury did The Reed Paper Company in Dryden Ontario dump into the Wabigoon River (upstream of the Winnipeg River) between 1962 and 1970?

9 tonnes

83.  Even though the mercury contamination entered the river prior to 1970, 90% of the people in Grassy Narrows still have symptoms of mercury poisoning 50 years later.

Correct

84.  List 5 symptoms of mercury poisoning

Numbness in extremities, numbness around mouth and nose, constriction of visual field, impaired hearing, slurred speech

85.  What did recent research on the concentration of mercury in sediments upstream and downstream of The Reed Paper Company show? 

High concentrations of mercury in the sediments at sites adjacent and downstream of the former chlor-alkali plant, where there is shown to be recent sedimentation, is strong evidence of an ongoing point-source of mercury to the river from the former chlor-alkali plant site. The warrants further investigation of the former chlor-alkali plant site and its surroundings.

86.  Over 300 million tons of plastic is produced every year and it is estimated that _________ tons enter the world’s oceans each year.

8 million metric

87.  List two reasons why microplastics are bad for aquatic organisms?

Ingestion: aquatic organisms like fish and plankton, can mistake microplastics for food, leading to ingestion. This can cause physical harm, block digestive systems, and reduce the ability to absorb nutrients

Toxicity: microplastics can absorb and carry harmful chemicals, such as pesticides or heavy metals, causing long-term health issues like reproductive problems or even death.

88.  Globally, to date, it is estimated that this percentage _______ of plastic that has been produced has NOT been recycled.

91%

89.  If we keep on our current path, by 2050 there will be more plastic in the ocean (by mass) than what?

fish

90.  Plastic in the world’s oceans tends to accumulate in one of 5 regions known as __________. 

Gyres

91.  Recent research by The Ocean Cleanup has revealed that the North Pacific Garbage Patch is roughly this size?

2 times the size of Texas or 3 times the size of France

92.  In their research, what percentage of ocean plastic is considered to be microplastic and what percentage is made up of much larger pieces that will eventually break down into microplastics?

92% is larger plastic that eventually breaks down

93.  A variety of marine animals are harmed by plastic – name two ways that plastic can harm marine animals.

Ingestion and entanglement

94.  List 5 things you can do to reduce the likelihood of plastics ending up near our waterways?

Use reusable beverage containers, don’t use straws (use a resuable one), purchase items with less packaging, avoid products with microbeads, quit smoking,

95.  The layer of atmosphere closest to the earth is called the __________. it extends from the surface of the Earth up to about _____ km.  As you move upwards in this layer of the atmosphere temperature _____ about 6^oC for every 1000 m increase in elevation.  This is the layer where all of our weather occurs.

Troposphere, 17km, Cools

96.  The second layer of the atmosphere extends from about 17 km upwards to about _____ km.  It is called the _________ and is where we find the largest concertation of ________ that protects us from harmful UV radiation.  In this layer of the atmosphere, temperature _________ as you move up in elevation. 

48 km, stratosphere, ozone, increases

97.  More than 99% of the gases in the atmosphere are composed of these 4 gases?

Nitrogen, oxygen, argon, water vapour

98.  This gas makes up about 78% ___________ , this about 21% ____________________, this a range from 0.01 to up to 4% ________________ and this one a little under 1% ___________

Nitrogen, Oxygen, water vapour, argon

99.  O₃ is most concentrated in the stratosphere between ______ and ______ km in altitude.

17 and 35 km

100. What’s the difference between a primary and secondary pollutant?

Primary pollutants are emitted directly to troposphere in a harmful form. Secondary pollutants are when some of these primary pollutants react with one another or with the basic components of air to form new pollutants

101. Identify 5 types of air pollution?

Carbon monoxide, nitrogen dioxide, sulphur dioxide, photochemical oxidants, radioactive substances

102. A major contributing factor to air pollution and acid deposition...is burning things such as…

Powerplants, ore smelters, and other industrial plants

103. What is smog? Photochemical vs. industrial...

Smog is a mixture of smoke and fog. Photochemical smog is a mixture of air pollutants formed by the reaction of nitrogen oxides and volatile organic hydrocarbons under the influence of sunlight. Industrial smog is a mixture of sulphur dioxide, droplets of sulphuric acid, and a variety of suspended solid particles emitted by burning coal and oil

104. List some effects of acid deposition – this is a good example of how all things/organisms are linked to their abiotic environment and to each other. 

Respiratory diseases (asthma, lung cancer, chronic bronchitis), more acidic pH results in leaching of toxic metals, reduces aluminum availability to plants/trees, calcium deficiencies in plants passed up the food chain, fish toxicity due to lower pH and aluminum.

105. Compare and contrast types of indoor air pollution in developed and developing countries

Four most dangerous indoor air pollutants in developed countries are cigarette smoke, formaldehyde, radioactive radon-222 gas, and very small and ultrafine particles. In developing countries, indoor air pollution from open fires and leaky and inefficient stoves that burn wood, charcoal, or coal could be reduced if governments gave people inexpensive clay or metal stoves.

106.   Why is indoor air pollution near the top of the list for cancer risk compared to outdoor pollution?

Levels of 11 common pollutants are 2-5 times higher in indoor air. The health risks from exposure to such chemicals are magnified because people typically spend 70% to 98% of their time indoors or inside vehicles

107. List some air pollution solutions for both stationary and mobile sources

Stationary: burn low-sulphur coal, remove sulphur from coal. Shift to less polluting fuels, remove pollutants after combustion

Mobile: mass transit, bicycles and walking, less-polluting engines, less-polluting fuels, improving fuel efficiency

108. What about air pollution solutions for indoor air quality?

Cover ceiling tiles and the lining of AC ducts to prevent release of mineral fibres, ban smoking, prevent radon infiltration, use office machines in well-ventilated areas

109. How have atmospheric levels of carbon dioxide fluctuated with temperature the past 400,000 (years ago?)

Temperature has shifted due to volcanic emissions, changes in solar energy input, continents moving as a result of shifting tectonic plates, strikes by large metorites, and other factors

110. What are three most notable greenhouse gases and what has happened with their concentrations in the last 100 years?

Carbon dioxide, water vapour, methane. Humans have increased these concentrations by burning fossil fuels, clearing and burning forests and grasslands, raising large numbers of livestock such as cattle, and using inorganic fertilizers

111. The current president of the U.S. likes to point the finger at China and say they are the largest carbon emitter – why is this not entirely accurate?  Why is finger pointing not helpful?

China has been producing large amounts of Co2 for a relatively short time and is estimated to have contributed about 5% of the world’s cumulative Co2 emissions compared to 25% generated by the United States.

112. What is happening to ice in the Arctic?  Why should this increase the amount of warming in the Arctic?

Sea ice in the arctic region has declined in area and volume because of climate change. As ice melts, the darker ocean surface absorbs more sunlight, which increases the amount of heat in the arctic. Less ice means more heat absorption, leading to more climate change.

113. How do we expect weather systems to be affected in a warmer climate (which has, by definition) more energy?

Warmer temperatures create more clouds that could warm or cool the troposphere. Warmer temperatures increase evaporation of surface water and create more clouds. These additional clouds can have a warming effect, by absorbing and releasing heat into the troposphere, or a cooling effect by reflecting more sunlight back into space

114. What do we expect is going to happen with respect to forest fires in Canada in the next century as a result of climate change?

Increase frequency and severity, greater area burned.

115. List 6 other potential effects of climate change

Sea level rise, loss of biodiversity, ocean acidification, food and water insecurity, spread of diseases, economic disruption

116. What are some things you can do as an individual to reduce your carbon footprint...and what kinds of solution to global warming are provided in your textbook (Page 577)? 

To reduce carbon footprint; eat less meat, reduce food waste, recycle more, drive less, reduce energy consumption. Solutions to global warming: cut fossil fuel use, shift from coal to natural gas, improve energy efficiency, shift to renewable energy resources, reduce poverty, slow population growth.

117. Ozone is a component of photochemical smog, is highly reactive and is a lung irritant...but in the stratosphere, it is very important for protecting the planet from ultraviolet radiation__.

118. In the stratosphere, how is ozone naturally formed and degraded?

It is formed when the ultraviolet radiation from the sun splits oxygen molecules into oxygen atoms, which then react with other oxygen molecules to form ozone. The greatest amount of ozone production occurs in the tropical stratosphere

It is degraded constantly by other gases in the stratosphere, such as those containing nitrogen and hydrogen. These gases convert ozone back into oxygen

119. What happens to the degradation rate of ozone when we add CFCs?

CFCs would damage the ozone layer. Can increase the amount of harmful ultraviolet energy reaching the earth by reducing ozone levels in the stratosphere

120. What are CFCs?

Are chloroflurocarbons, which are highly stable, non-toxic and used as propellants in aerosol spray, in Styrofoam production, and in refrigeration and air conditioning units

121. What are some of the effects on living organisms from elevated UV?

Skin cancer, sunburn, premature aging, eye damage, immune system suppression

122. Populations of organisms share resources and interact with one another.  Population ecology looks at the distribution of populations; there are three basic distribution patterns – they are ______, _______ and ________ and the most common is _________.

Random, Rare, most common is clumped

123. We discussed 2 basic types of growth in a population – exponential and logistic.

Exponential growth- a population grows at a fixed rate, such as 1% or 2%. The growth curve starts slowly and grows faster as the population increases because the base size of the population is growing

Logistic growth- involves rapid exponential population growth followed by a steady decrease in population growth with time, until the population size levels off

124. what is K? carrying capacity- when a population exceeds its resource supplies, many of its members die unless they can switch to new resources are move to an area with more resources

125. What is r?  Biotic potential? Environmental resistance?

R- intrinsic rate of increase: rate at which a population would grow if it had unlimited resources

Biotic potential: populations vary in their capacity for growth

environmental resistance: all the factors that act to limit the growth of a population

126. What can happen when carrying capacity is exceeded?  We looked at 2 examples. 

When a population exceeds its resource supplies, many of its members die unless they can switch to new resources are move to an area with more resources. They use up their resource supplies and temporarily overshoot, or exceed carrying capacity of their environment. This occurs because of a reproductive time lag: the period needed for the birth rate to fall and the death rate to rise in response to resource over-consumption. In such cases, the population suffers a dieback, or crash, unless the excess individuals can switch to new resources or move to an area with more resources

127. What are the characteristics of r and K species?  Provide some examples of each.

R- Species with a capacity for a high rate of population species. Have many small, offspring and give them little parental care. They reproduce early and put most of their energy into reproduction (example; algae, bacteria, rodents, most insects)

K- tend to reproduce late in life and have a smaller number of offspring with fairly long life spans. Offspring develop inside their mothers, are born fairly large, mature slowly, and are cared for and protected by one or both parents until they reach reproductive age. (large mammals; bears, whales, humans)

128. What is a survivorship curve and what does it tell us about the life history of animals (their reproductive strategy)?

They can be used to compare the survival of different species, different populations of a given species, or different genders of a given species. Survivorship curves show how the number of individuals in a population decreases over time.

129. List examples of species with Type I, Type II and Type III survivorship curves.

Type 1: humans and most mammals: have low infant mortality and provide a lot of care for their offspring

Type II: brids, small mammals, and small reptiles: have relatively constant mortality rates throughout their lifespan

Type III: trees, marine invertebrates, and most fish. They have very high juvenile mortality, but those that survive to adulthood are likely to have long lives

130. How do we calculate a change in population? 

(births+immigration) – (deaths+emigration)

131. When did the world achieve its maximum population growth rate and what was it (i.e. %)?  By 2014 the global rate of population increase had dropped to ____ %

1.2%

132. What is a crude birth rate?

The numbers of births/1000 people per year

133. What is a crude death rate?

The number of deaths per 1000 people per year

134. This continent has a crude birth rate twice that of other developing areas and 3 times that of Europe or Canada?

Africa

135. What is meant by a total fertility rate (TFR)?

The average number of children a women typically has during her reproductive years

136. As a globe, even if we reduce our rate of population growth over the coming decades our populations will continue to increase.  Why?

Because of population momentum. This is because many countries will still have a large number of young people entering childbearing age, which will continue to drive births even as fertility rates decline. Additionally, improvements in healthcare have reduced death rates, leading to longer life expectancy and continued population growth. High fertility rates will sustain population growth for decades.

137. What are 5 ways we can work to reduce the rate of human population growth? – Note – key is educating and empowering women!

138.  What is a population age structure?

Can be used to predict future population growth and also to assess the needs of those populations

139. What does a population age structure look like for a rapidly growing, slow growing and slow or negatively growing population?

A rapidly growing population: a broad base that narrows towards the top. A larger proportion is in younger age groups, indicating high birth rates. The population is expanding quickly, with many individuals entering reproductive age and contributing to future growth

Slow growing population: the base is relatively broad, but it is more uniform across age groups or has a slightly smaller base than in the rapidly growing population. There is still a fair number of young people, but birth rates have decreased, and the population is growing at a slower pace. The populations age structure is more balanced, with more individuals in older age groups compared to the rapidly growing population

Slow/negatively growing population: a narrow base with a larger proportion of the population in older age groups, and a relatively smaller number of young people. The population growth rate is either very slow or negative, which can be due to low birth rates, high death rates, or both. May be more elderly people than young people, and the proportion of the population in reproductive age is shrinking

140. In the year 2013, this percentage of people on the planet were under the age of 15? 

2 billion

141. What do we mean by a demographic transition?  Explain its four stages and how it works.

Occurs as countries become industrialized and more economically developed. It is a transition from high birth and death rates to low birth and death rates, with rapid population growth between as the death rate falls, but the birth rates remain high