Science Section 1 Flashcards
What is environmental science?
the study of the impacts of human activities on environmental systems
True or False: The earth is going through a mass extinction
True
What is the environment?
the sum total of all the conditions and living and nonliving factors that surround an organism
What do we use as an indicator of environmental quality
Species diversity
What is the global population
8 billion from November 2022
How many new inhabitant are there each day (number of births minus the number of deaths)
230,000
What are the conditions that inhabit an environment?
Others of a species, food sources, predators, weather, and landscape
Until what year was the world going through Exponential growth
1960s
True or False: Human population is going through exponential growth
False
What is a local environment?
the area immediately surrounding an organism
What is a global environment?
the sum of all aspects of the earth
For the more people on Earth there will be a greater demand for what
Finite resources (energy, food, water, land, pollution, wate)
True or False: Environmental science is interdisciplinary
True
What aspects go into environmental science?
Biology, earth/atmospheric sciences, fundamental principles of chemistry and physics, human population dynamics, and biological/natural resources.
What does the word “intensity” mean in terms of agriculture
how much food is grown per hectare or acre of land
Food Grains such as wheat, corn, and rice provide more than what eaten by humans
Calories
What is a system?
a set of living and/or nonliving components connected in such a way that changes in one part of a system affect the other parts
True or False: A system can’t be isolated or studied apart from other systems.
False
What does monoculture mean in agriculture?
one crop
what does polyculture mean?
multiple crops
What can High-Intensity agricultural practices lead too?
Soil erosion, runoff fertilizers, animal wastes into waterways, and buildup pesticde
More people regardless of their life or where they live means ____
a greater environmental impact.
What can cause resource use to vary?
Region, Economy, And Country
According to United Nations Development Program 20% of people in what kind of country consume 45% of all meat and fish?
Developed Countries
What percent of total energy do Developed Countries Consume?
58%
Developed Countries Consume What percent of paper?
84%
What causes Sustainable use?
When present-day consumption allow adequate supply to remain for future generations
What impacts our Grain Production?
The quality of Soils, Climate Conditions, Land Under Cultivation, Human Labor, Energy, and water expended
How much of Worlds automobiles and trucks are own by developed countries?
87%
What do layers of snow and ice contain?
Each layer contains bubbles of trapped gases in concentrations that reflect their atmospheric concentrations at the same time the layer was sealed off from the atmosphere.
What happens to ice cores after they are extracted?
It is kept frozen then is taken to a lab and a researcher assigns a date to each annual layer corresponding to the year when it was deposited on the surface as snowfall.
What is the chemical symbol for the metal lead?
Pb
What does metal lead do to humans, plants and animals?
Metal lead impairs human central nervous system function and is toxic to most plants and animals.
True or False. Metal lead is hard.
False
What is the amount of lead in the atmosphere, water, soils, and plants and animals an indicator of?
The amount of pollution that has been introduced into the natural environment.
What do things contain small amounts of lead in them?
Coal and oil
What is the scientific method?
An objective way to explore the natural world, draw inferences from it, and predict the outcome of certain events, processes, or alterations.
How many parts are there to the process of scientific inquiry?
6
If we don’t change our industrial society what will create more what?
pollution and waste
What three food grains provide more than half the calories eaten by humans?
Wheat, corn, and rice
Worldwide grain production is a result of the quality of what?
soils
What does the term intensity refer to in the context agriculture
The amount of food that is grown per hectare or acre of land.
High intensity agricultural practices often lead to what?
soil erosion
True or False: it is simple to determine the sustainability of a given society.
False
When the population increases what other thing also increases?
Consumption of resources
How is an observational experiment conducted?
By observing phenomena in the natural world without any interference by the researcher.
What’s the difference between an observational experiment and a manipulation experiment?
The person conducting an observational experiment doesn’t change anything.
What are the four steps of the scientific method
Observe, Generate a hypothesis, Based on existing info, Test the hypothesis
T/F The scientific is NOT an ongoing discussion among researchers.
False
What dose it mean to observe when doing the scientific method
Observe the natural world, without interference, and ask questions about the observations
Scientists have observed that species diversity, is affected by ___
The alteration of habitat.
What does it mean to generate a hypothesis when doing the scientific method
Make a general statement about the organism or prosses under observation, that could answer a question
What is 1 hectare converted to acres?
2.47 acres
What will most likely happen to the diversity of species of small mammals and shrubs if the size of a natural area is reduced from ten hectares to 1 hectare?
Reducing the size of a natural area will result in a significant loss in small mammal and shrub species.
How can we judge whether a report is based on good science?
In order to conduct a scientifically sound study, the investigators must use a large enough sample size and have a distinct difference between the experimental group and the control group.
What is the biggest limitation of Environmental Science?
The greatest challenge is the fact that there is no undisturbed baseline with which to compare the contemporary Earth.
Why is it difficult to know the “original” levels of lead?
This is because humans have altered virtually every part of the Earth, which makes it difficult to know the levels of certain resources and species before human alteration.
What are joules?
The SI unit of work or energy, scientists primarily use this measurement along with calories.
Who does benzene pose a risk to?
People
Who does chlorine pose a risk to?
Organisms in a stream
From 1975 to 2021, fuel efficiency in the U.S has increased in most cars from an avg of 13 miles per gallon to more than 30 miles per gallon. Why didn’t the overall avg miles per gallon of vehicles in the U.S steadily increase?
Due to consumer preferences, people bought cars that often got less than 20 miles to the gallon, which brought the overall average fuel efficiency down in the 1990s.
What does the phrase, “A butterfly stirring the air in Beijing can affect weather patterns in New York a month later” mean?
It is a poetic way of describing how the systems of Earth are interconnected.
All environmental systems involve the exchange of ___ or ___
Matter or energy
Name one of the most important materials involved in environmental systems?
Water/Oil/Coal/Oxygen
What is an open system?
An open system is one where the exchange of matter or energy between it and other systems occur.
What is a closed system?
In a closed system, exchange does not occur.
Is the Earth a closed or open system?
The Earth system is open with respect to energy, but the Earth system is closed with respect to matter.
When solar radiation enters the Earth system, what happens?
Energy leaves it in the form of heat and reflected light.
Are there any major inputs or outputs of matter in the Earth system?
No
Which areas of human endeavor are the most important?
Economics, Social structures and institutions, Law, Policy, and Environmental advocacy and action.
What affect would new scientific data on global warming have on polices and laws?
It would affect new policies and laws related to greenhouse gas production, as well as ways to adapt to a changing climate.
What is a system analysis compared to?
An analysis that you would perform on your checking account to figure out your financial status.
What do systems analysts call a balance.
They call that balance a pool.
What is a flux in the context of the packet?
The inputs (what goes in) and outputs (what goes out) of any given system.
What is a flux rate?
A flow per unit of time.
What happens when the inputs are greater than the outputs?
You get a positive flux.
How can all types of balance analyses be represented?
Net Flux = Inputs - Outputs
Why is a system analysis referred to as a mass balance analysis?
Because it was designed to be done for materials that have mass.
What is another name for a joule
a calorie
What is the most important aspect of conducting a mass, energy, or monetary analysis?
The most important aspect of conducting a mass, energy, or monetary balance analysis is learning if your system
is in steady state.
What is steady state?
Steady state—that is, if input equals output and the size of the pool does not change over time.
Water in the atmosphere is in a steady state. What Greenhouse gas is NOT in a steady state?
Carbon Dioxide
Most “pools” are in a steady state. T/F
True
“4 Interconnected environmental systems are critical to the Mono Lake Story.” What are those 4 systems?
Natural Water System, Salt Balance, Ecological, & Water Use
Mono Lake is called a “terminal lake” because of what Unique Geography about it?
It is the lowest point in the area, water flows in, but it cant flow out.
The salt concentration in Lake Mono slowly… Increases or Decreases?
Increases
How much saltier does Lake Mono get every year. (Hint, mg per day)
5000 mg per day
What big City is Lake Mono located by?
Los Angeles
The Oceans warming is an example of a +/- feedback loop
Positive feedback loop
What animal is the base of the food chain near lake Mono.
Algae
What year was the draining of Lake Mono finally regulated
1983
What is the formula for the Mean Residence Time in a steady state?
MRT = (Pool) Divided by (Flux In Or Out)
Tsavo National Park gets how much rain per year?
500 mm
Out of 20 habitats how many meet the require 1,000 miles for a habitat for an elephant?
7 habitats
What is a set point?
the stable value for the parameter under examination
What is it called when the set point is exceeded?
the overshoot (happens when there are delays transmittance of information)
What is the carrying capacity?
the number of organisms that can be sustained indefinitely without the habitat becoming degraded
According to Figure 15, after an overshoot occurs and the parameter starts to decrease again what happens to the carrying capacity?
it becomes degraded (the carrying capacity is lessened because the resources have been too exploited and overconsumed)
What are the two inputs and two outputs regarding the size of the population?
number of births and amount of immigration (input) and the number of deaths and the amount of emigration (output)
What type of feedback is seen in a typical wolf-deer system in which the amount of predation increases as the number of prey increases?
Positive feedback
What are the two main reasons for the decline of elephants in central and southern Africa?
loss of habitat as humans have cultivated the land for agriculture and poaching them for their ivory
Who passed a ban on ivory because of the African elephants’ population decline in 1989?
CITES (Convention on International Trade in Endangered Species)
True or False? The ban on ivory the Convention on International Trade in Endangered Species was effective.
False, illegal trade in ivory still continues along with using the elephants’ land for farming
In what area of Africa is poaching a more sever problem for elephants?
Kenya, east Africa
Approximately how many millions of elephants were killed for their tusks during the 1970s’ ?
1.5 million elephants
What type of feedback loop is the Human-Elephant population system? Describe it as well
It is a positive feedback loop. As demand for ivory and poaching increases the elephant population decreases which causes their ivory to become scarce and further increases the demand and leads to more poaching; invertedly having the same effects
What is population density?
the number of animals per kilometers squared
What three types of density-dependent feedback loops (meaning they change with the population density and are negative feedback loops like the human-elephant population)?
1). increase in death rates or decrease in birth rates due to a shortage of food 2). increase in death rates due to increases in predation, parasitism, or disease 3). increase in death rates or a decrease in birth rates due to increased intensity of social interactions within a population
What is parasitism?
a biological relationship involving one species obtaining nourishment from a host, usually without causing its death
What has happened to elephants’ food resources in Kenya?
it is being reduced through the conversion of natural savannas to farmland or to deserts
What is the name of the national park in south eastern Kenya that houses most of the elephant population and it gets less then 500 mm of rain a year so it doesn’t have as much vegetation?
Tsavo National Park
What are Red Spruce Trees primarily used for?
making pulp and paper
What is acid rain?
acid deposition that results when rain combines with the air pollutants sulfur dioxide and nitrogen oxides to produce rain with a pH value of 4.0, instead of the pH of 5.0 to 5.5 of normal rain
What did the surveys taken in 1964 and 1982 at Whiteface Mountain in New York revealed the Red Spruce Trees?
that the their population had decreased by almost 70% in eighteen years (the cause was not because of natural factors i.e. droughts and diseases) meaning it was caused by human caused pollution
True or False? At a higher elevation, Red Spruce Trees were more likely to survive.
False, at a higher elevation the temperature is colder, higher winds, thinner soil, and fewer nutrients in the soil. But there is also more pollution as elevation increases.
What was happening in the fossil fuel industry at the same time the Red Spruce Trees population were declining (1960-90)?
Large amounts of sulfuric dioxide were released into the atmosphere with the combustion of oil and coal, this would lead to the formation of sulfuric acid which is a component of acid rain
True or False? Red Spruce Trees do not need calcium
False, calcium deficiencies adversely affect trees’ ability to withstand cold temperatures
What did the system analysis of the Red Spruce Trees conclude about their decline?
it was a combination of cold temperatures (natural factors) and a pollutant (sulfate)
How do scientist know that global temperatures, and atmospheric concentrations of carbon dioxide and methane have fluctuated frequently?
Looking at ice cores
Each layer of ice sheets and glaciers contain what? (apart from snow and ice)
bubbles of trapped gases
In the last 800,000 years what year did both Co2 and Ch4 start to rapidly increase?
Mid 1900
Before recent years had Co2 and Ch4 amounts been declining or increasing?
Declining
How do scientist test ice for elements and gases?
drilling into the layers of buries ice and carefully remove an ice core
What is chemical Pb?
lead
What does lead impair in humans?
central nervous system
Lead is a major ingredient in what material?
paint
What is the major source of lead contamination in America?
drinking water
True or False: Elephants are very social within their groups even in overcrowded situations they don’t fight.
False: In overcrowded situation the elephants do tend to fight with each other with can lead to increase death rates, emigration rates, and reduced birth rates.
True or False: In Kenya, elephant food is decreasing due to the conversion of natural savannas to farmland or to deserts.
True
Where do Red Spruce trees grow?
They grow in some forests in the eastern United States along the Appalachian Mountain chain from New England to Georgia.
True or false: Red Spruce is a needle-bearing tree that can live for 300 years or more.
True
Why did the red spruce system in the northeastern US become important in the 1980s?
The trees started to have an unexplainable decline in number and health
When did red spruce in North America start to have unexplainable deaths?
There has been reports dating back to 1870
In 1980 what phenomenon of pollution led environmental scientists to suspect there was a link to red spruce damages.
Acid rain
True or False: There is no single indicator that effectively assesses the whole planet
True
True or False: One environmental indicator can only indicate one thing
True
Are rates of change important when considering environmental indicators?
Yes
How might the importance of a measurement be best understood?
in context of a pattern of measurements
How is human population measured?
by individuals
How is ecological footprint measured?
hectares of land
How is per capita food production measured?
kg of grain/person
How is total food production measured?
kg of grain/hectare of land
How is carbon dioxide measured?
concentration in air (ppm)
How is global temperature measured?
degrees Centigrade
How is sea level change measured?
mm
What Unit of Measurement is used to measure annual precipitation?
mm
How is species diversity measured?
number of species per functional group
How are fish consumption advisories measured?
present or absent; or number of fish allowed per week
How is ambient water quality (toxics) measured?
concentration
How is ambient water quality (conventional) measured?
concentration; presence or absence of bacteria
How are atmospheric disposition rates measured?
quantity per unit area per time
How is fish catch/harvest measured?
weight of fish per annum or weight of fish per effort expended
How is extinction rate measured?
number of mammal species per 10,000 species per 100 years
How is habitat loss rate measured?
land cleared or “lost” per year
How is the infant mortality rate measured?
number of deaths of infants under age 1 per 1,000 live births
How is life expectancy measured?
average number of years a newborn infant can be expected to live under current conditions
What are the six environmental indicators?
biological diversity, human population growth, food production, resource consumption, global temperature and atmospheric greenhouse gas levels, and pollution levels
What does biological diversity entail?
the diversity of genes, species, habitats, and ecosystems on earth
What is a species?
a group of organisms that is distinct from other groups in morphology, physiology, or biochemical properties
What is morphology?
body type
How many ‘known’ species are there on Earth?
approximately 1.8 million
What defines “known”?
identified and catalogued species
How many more species might there be?
somewhere around 10x that known number, due to most species, especially microbial ones, aren’t identified or catalogued
What percent of species that have lived on Earth are extinct?
roughly 99.9%
What are quiet periods?
time periods with no massive environmental or biological upheaval
What is the estimate for background extinction rates?
two mammal extinctions per 10,000 species per 100 years
True or False: Human beings have greatly accelerated species extinction rates.
TRUE ; by up to 100x than background extinction rates
How many species per year are currently going extinct?
40,000
What are the matter inputs for humans
Food and Drinks
What are the matter outputs for humans
Waste
are individual countries open or closed systems
Open system
What Mountain’s snowmelt flows into the Mono lake river?
Water flows into the lake from tributaries bringing water from snowmelt in the Sierra Nevada Mountains,
Why is it important to determine the net flux of a pollutant?
If a pollutant is accumulating in a drinking water reservoir, it may be valuable to know the time when pollutant concentrations will become toxic to organisms in the reservoir or to humans drinking the water in the reservoir.
What year did LA start withdrawing water from the Mono lake?
1942
How many gallons of water a day were remove from the Mono Lake each day?
80.4 million gallons/day.
How many feet did the lake level dropped in 40 years?
40 feet
What is MRT in the context of air pollutants?
MRT is the period that an average molecule will remain chemically active in the atmosphere.
How old is the Mono lake?
Between 1 and 3 million years old, making it one of the oldest lakes in North America.
What is the residence time for Carbon dioxide in the atmosphere?
100 years
What is the residence time for Hydrofluorocarbons in the atmosphere?
222 years
T/F Residence time is valid only if the system is in steady state.
True
How can we calculate accumulation or depletion rates?
We can calculate accumulation or depletion rates by using the formula for net flux.
What is the formula for net flux?
Net Flux = Inputs – Outputs
What is negative feedback?
A negative feedback loop is the behavior in which the system variable is brought back to a starting point.
What is positive feedback?
A positive feedback loop is where a system variable is continuously moved away from the stable point that is often called a vicious cycle.
How does water vapor contribute to global warming?
Warmer temperatures at the Earth’s surface lead to greater evaporation from oceans and lakes. The additional moisture in the atmosphere from evaporation enhances the layer of heat-trapping gases, including water vapor, that cover the Earth, which makes the Earth warmer, which leads to greater evaporation, and more warming, creating a positive feedback loop.
Are oceans in steady state?
Yes, the oceans are also at steady state; the water that enters from rivers and streams is roughly equal to the water that evaporates.
How did the increase in salinity in Mono lake affect algae and the population that depended on it?
Higher salinity slows the uptake of nitrogen from the decayed animals and their excretions. Since nitrogen is a critical element for growth, slower nitrogen uptake led to slower growth of the algae population and less food for the flies and shrimp and thus eventually for the birds. By the early 1980s, Mono Lake and the populations that depended upon it were dying.
What are the two notable effect from lowering water levels in ecosystem of the Mono lake?
First, lower water level expose Tufa tower which is the habitat of shrimp and flies. Because they were expose their predator (gulls) could prey on them easily. This led to over predation and a decline in shrimp and flies which eventually led to a decline in gulls because they had little food. Secondly, as the lake level went down, alkaline dust was exposed, leading to vast dust storms affecting bird and other nearby wildlife populations.
Environmental scientists aim to understand how
humans influence the natural environment
An environment consists of
all biotic and abiotic factors in an organism’s surroundings
Predators, prey, and weather are all part of
the environment
Environmental science is BEST described as
interdisciplinary
Which of the following characteristics is NOT a defining part of an environmental system?
a. A system consists of both biotic and abiotic components.
b. Systems require formal recognition before being studied.
c. The size of a system can vary widely, from a beehive to the Earth.
d. A system can be studied independently from any other system.
e. Systems are interconnected.
Systems require formal recognition before being studied.
How does measuring environmental health differ MOST from measuring human health?
Environmental systems have more complexity than the human body.
An environmental indicator
assess how healthy an environment is
Which of the following factors is NOT an important consideration in how environmental indicators should be interpreted?
a. time of measurement
b. rates of change
c. contextual patterns
d. location of measurement
e. public opinion
public opinion
Which environmental indicator is commonly used to measure global environmental health?
species diversity, human population size, atmospheric carbon dioxide concertrations
Ecological footprint is measured in
hectares of land, it is the combined land and sea area needed for a human population to obtain the resources it needs
What characteristics define a species?
body types, physiology, biochemical characteristices, reproduction/offspring viability
What percentage of species in all of Earth’s history have experienced extinction?
99.9 percent
The current primary cause of extinction is
human-caused habitat deterioration
The American bison, peregrine falcon, and California condor are species that
have been the target of restoration efforts
What conclusions can be drawn from modern species diversity?
Current declines in species diversity indicate that changes to environmental quality are worsening.
In which decade did the global human population stop growing exponentially?
1960s
In how many years did the human population grow from three billion to four billion?
14
As an environmental indicator, the human population size suggests that
environmental health will decline because of greater resource needs and pollution caused by population growth
Over half of global human caloric consumption consists of
grains, including wheat, corn and rice
Which of the following concerns is NOT associated with high-intensity agriculture?
a. fertilizer runoff
b. pesticide buildup
c. soil erosion
d. waterway pollution
e. low initial yield
low initial yield
A key condition of sustainable use is that
current resource use does not excessively deplete resources needed for future generations
What characteristics influence resource consumption?
regional economies, population size, patterns of energy use, national lifestyles
The twenty percent of the population in developed countries uses
fifty-eight percent of total energy
The majority of human-created carbon dioxide comes from
fossil fuel combustion
Increasing carbon dioxide levels are BEST described as
anthropogenic
Between 1960 and 2020, carbon dioxide levels increased by approximately
100 ppm
One of the hardest challenges for environmental scientists is
determining ancient levels of chemicals
Lead has an especially adverse effect on
developing brains
Lead concentrations indirectly imply that
human activity can cause environmental harm
What has contributed to lead pollution
increased automobile use, coal burning for energy, historic mining practice, advances in refining techniques
How did clean air legislation in 1975 decrease lead emissions?
A transition from leaded to unleaded gasoline caused a decrease in lead pollution from automobile use.
Lead is often present in houses built before 1960 because of its use in
paint
Lower-income communities are more commonly affected by lead pollution in water because of
plumbing fixtures
The first step of the scientific method is to
observe the world
Which of the following experimental designs is an example of a manipulation experiment?
a. To understand predator-prey interactions, scientists play recordings of different bird species and analyze the resulting frog behaviors.
b. Scientists survey 500 homes in different socioeconomic levels to understand the demographics associated with living in homes with asbestos.
c. The migration patterns of 500 birds are observed. Scientists attempt to predict future changes in these patterns.
d. Recordings of fifty dolphins are analyzed to understand how other species communicate.
e. Air quality measurements are taken around ten refineries. Conclusions from the data are used to promote environmental policy.
To understand predator-prey interactions, scientists play recordings of different bird species and analyze the resulting frog behaviors.
A research group collects data on ten forests before a dry season in which several wildfires are predicted. After wildfires occur in three forests, the group collects additional data in each forest. The controls for this study are the
seven forests without a wildfire
Water acidity is measured in twenty locations across one river. Ten locations are adjacent to a coal refinery, and ten locations serve as controls. The experimental variable for this experiment is
location next to a refinery
According to the USAD Science Resource Guide, the sixth major step of the scientific method is to
report finding
Unlike scientific theories, scientific laws are
thought to hold true in all conditions
To gain credibility, a scientific finding must be
replicated
Which of the following characteristics is NOT a requirement for a scientific study?
a. proposed mechanisms for results
b. sufficient sample size
c. distinct control and experimental groups
d. correlation between events
e. causal relationship between variables
correlation between events
The PRIMARY limitation facing environmental scientists is the
missing baseline for comparison, humans have altered the entire planet so there is no baseline
What unit do scientists use to measure energy?
joules
An advocate for paper bag use instead of plastic bags would MOST likely support the value judgment that
benzene is more harmful to the environment than chlorine
benzene is used to make plastic bags and chlorine is used to make paper bags
How many years passed before the average fuel efficiency of U.S. cars increased from thirteen miles per gallon to over thirty miles per gallon?
46
In the 1990s, average fuel efficiency
decreased because of consumer preferences for vehicles with lower fuel efficiency
How are systems defined?
A researcher chooses a system of study
All environmental systems exchange
matter or energy
Which description BEST defines an open system?
a. the easiest system for environmental scientists to study
b. a system that lacks the environmental policy regulations of closed systems
c. a system that constantly gains energy from other systems
d. typically a biological or physiological system
e. a system that allows matter or energy to enter or leave respective to other systems
a system that allows matter or energy to enter or leave respective to other systems
In terms of systems analysis, how does the Earth differ from an ecosystem?
The Earth is a closed system with respect to matter
System analysis is analogous to
managing a checking account
Info: The balance of the account is analogous to the pool of a system, while deposits and expenditures are considered the inputs and outputs.
All elements of a system make up the system’s
pool
Flux calculations for materials in a system are used for
mass balance analysis
A system with 85 joules of energy input has an output of 20 joules of energy. The flux of this system is
65 joules
In systems analysis, a system with equal inputs and outputs is in
steady state
Which of the following systems has a flux of zero?
a. a flooding river
b. atmospheric carbon dioxide
c. melting ice caps
d. plastic in the ocean
e. water in the atmosphere
water in the atmosphere
Info: Atmospheric water has a flux of zero because rates of evaporation are approximately equal to rates of precipitation
Which of the following mass balance statements BEST expresses the flux of the salinity of Mono Lake?
a. Positive output and no input lead to a positive net flux of salt into the lake.
b. Positive output and no input lead to a negative net flux of salt from the lake.
c. Positive input and no output lead to a negative net flux of salt into the lake.
d. No input nor output of sodium leads to a net flux of zero for the salt in the lake.
e. Positive input and no output lead to a positive net flux of salt into the lake.
Positive input and no output lead to a positive net flux of salt into the lake.
The organisms at the base of Mono Lake’s food chain are
algae
From the 1940s to the 1980s, the flux of water levels in Mono Lake was
negative 40 feet
Changing water levels in Mono Lake lead to
exposure of tufa towers, alkaline dust storms, increases in salinity, slower algal growth, decreased nitrogen uptake
The first individuals to respond to the changes in Mono Lake included
ecologists and environmental scientists
Mean residence time calculations require that a pool
is in a steady state
A lake contains 32 million gallons of water. If one million gallons of water enter the lake and two million gallons exit the lake each day, the mean residence time of the lake
cannot be calculated — has to be in a steady state
Which of the following gases has the LOWEST atmospheric lifetime?
a. hydrofluorocarbons
b. methane
c. nitrous oxides
d. carbon dioxide
e. chlorofluorocarbons
methane, has a residence time of 11.8 years
The accumulation rate of a pollutant is its
net flux
Which of the following examples describes a negative feedback loop?
a. The salinity of Mono Lake increases when water enters the lake from surrounding tributaries.
b. As the number of brine shrimp in Mono Lake increases, the rate of predation by gulls increases as well.
c. As water is diverted from tributaries, the water level of Mono Lake decreases.
d. Evaporation from lakes increases levels of greenhouse gases, leading to more evaporation.
e. Increased lake salinity because of climate change causes rates of nitrogen uptake to slow down.
As the number of brine shrimp in Mono Lake increases, the rate of predation by gulls increases as well.
The ideal value for a parameter of an environmental system is its
set point, when the parameter of a system is in balance
Why does overshoot occur in environmental systems?
Responses to changes in a system are often delayed, allowing a system to outpace its set point.
Net population change is best described as
the flux of a population
Info: Changes in population size are determined by outputs subtracted from inputs. The inputs-outputs expression used to calculate net population change is the same expression used in flux calculations.
Which of the following policies resulted from the 1989 CITES?
a. subsidies for research on red spruce death
b. restrictions on diversions from Mono Lake tributaries
c. limits on habitat destruction
d. regulations on wastewater in the Florida Everglades
e. prohibition of the ivory trade
prohibition of the ivory trade
The relationship between elephant deaths and the value of ivory is a(n)
positive feedback loop
Inadequate habitat size leads to all of the following concerns in elephant populations EXCEPT
a. increased emigration
b. increased violence
c. increased birth defects
d. increased death rates
e. high disease rates
increased birth defects
Industries mainly use red spruce to produce
pulp and paper
In what decade did red spruce populations decrease excessively?
1980s
Environmental scientists noticed an association between red spruce deaths and
acid rain
What term describes the quantity and size of red spruce trees?
basal area
A system analysis of red spruce led scientists to conclude that
sulfate pollution increased red spruce’s vulnerability to cold temperatures
The Florida Everglades watershed measures over
50,000 km squared
Which of the following descriptions BEST explains the alligator hole subsystem?
a. small pools surrounded by marsh plants
b. underwater tunnels connecting alligator habitats
c. large marshy basins with biodiverse aquatic life
d. small caves housing alligators
e. saline lakes with mangrove islands
small pools surrounded by marsh plants
The Water Resource Development Act of 2000 included
plans to manage various subsystems of the Florida Everglades
The Everglades Landscape Model involved all of the following principles EXCEPT
a. preservation of wetland biodiversity
b. adaptive management of the ecosystem
c. sufficient clean water in the watershed
d. decreased human-caused wastewater
e. greater water flow through the watershed
preservation of wetland biodiversity
Which issue would an opponent of the Everglades Landscape Model MOST likely cite as a flaw in the plan?
a. complexity of large-scale management
b. threats to biodiversity
c. insensitivity to Floridian culture
d. political controversy
e. short-term economic development
short-term economic development
In what decade did population growth first slow down?
1960s
Scientists estimate a current extinction rate of
40,000 species per year
The present state of biodiversity confirms environmental scientists’ claims of a sixth
mass extinction
Air and water pollution in the United States first decreased in the
1970s
Populations have a maximum ideal number of individuals called the
carrying capacity
Environmental scientists can study red spruce in
the northeastern United States
