Uno Flashcards
What is environmental science?
The study of the impacts of human activities on environmental systems.
What types of human activities are included in environmental science?
- Large-scale actions like clearing land for agriculture
- Fishing the oceans for food
- Mining for minerals and fuels
- Changing the planet’s climate through greenhouse gas emissions
- Everyday individual actions like driving a car and using containers
Define ‘environment’.
The sum total of all the conditions and living and nonliving factors that surround an organism.
What is a local environment?
The area immediately surrounding an organism or person.
What is a system in environmental science?
A set of living and/or nonliving components connected in such a way that changes in one part affect other parts.
List the six categories of environmental indicators.
- Biological diversity
- Human population growth
- Food production
- Resource consumption
- Global temperature and atmospheric greenhouse gas levels
- Pollution levels
What does overall biological diversity describe?
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.
How many known species are estimated to exist on Earth?
Approximately 1.8 million species.
What is the estimated background extinction rate for mammals?
Two mammal extinctions per 10,000 species per one hundred years.
True or False: Human activities have accelerated species extinction rates.
True.
What is the current global human population as of November 2022?
Eight billion people.
What is the projected world population by the year 2150?
Between 8 and 12 billion people.
What are food grains that provide more than half of the calories eaten by humans?
- Wheat
- Corn
- Rice
What does ‘intensity’ in agriculture refer to?
How much food is grown per hectare or acre of land.
What is sustainable use of resources?
Consumption that allows an adequate supply to remain for future generations.
What percentage of the world’s population consumes forty-five percent of all meat and fish?
Twenty percent of the people in developed countries.
What are greenhouse gases?
Gases that trap heat around the Earth, such as carbon dioxide and methane.
What human activity is the primary source of carbon dioxide?
Combustion of fossil fuels.
What is lead’s chemical symbol?
Pb.
Fill in the blank: An environmental indicator is a measure that reflects the _______ of a system.
environmental health
What is a keystone species?
A species of particular importance within an ecosystem that can cause a cascade of extinction of dependent species.
What factors regulate the temperature of the Earth?
- Incoming solar radiation
- Absorbed solar heat
- Surface area of ice caps and oceans
- Concentration of greenhouse gases
What has been the trend in global lead production over the past five thousand years?
Global lead production has increased.
What changes during the Industrial Revolution contributed to increased lead emissions?
Changes in refining techniques led to greater releases of lead into the atmosphere.
What role did coal and oil play in lead emissions?
Coal and oil contain small amounts of lead, which increased emissions as more of these fuels were burned.
How was lead used in automobiles?
Lead was used as an additive to gasoline to improve engine performance.
What legislation was enacted in 1975 regarding lead in gasoline?
Clean air legislation required new cars in the U.S. to use gasoline without lead.
What was the primary reason for the decrease in lead emissions in the 20th century?
The switch from leaded to unleaded gasoline.
True or False: The switch to unleaded gasoline completely eliminated lead emissions.
False.
What was a common use of lead in paint?
Lead was a major ingredient in paint.
What health risk is associated with lead paint in older houses?
Peeling paint can be ingested by young children, leading to lead pollution.
What is currently the major source of lead contamination in the U.S.?
Drinking water, particularly from lead pipes.
What happens to lead pipes over time, especially with acidic water?
They corrode, releasing lead into drinking water.
Define the scientific method.
An objective way to explore the natural world, draw inferences, and predict outcomes.
List the major steps of the scientific method.
- Observe
- Generate a hypothesis
- Test the hypothesis
- Accept, revise, or reject the hypothesis
- Report findings
- Replicate the experiment
What is a hypothesis?
A testable and falsifiable general statement about organisms or processes under observation.
What distinguishes an observational experiment from a manipulation experiment?
An observational experiment involves observing phenomena without interference, while a manipulation experiment involves changing an aspect of the environment.
What is the importance of sample size in experiments?
A large sample size ensures that data are representative of the entire population.
What happens if findings differ from the hypothesis?
The hypothesis is modified and retested.
What is a scientific theory?
A widely accepted hypothesis that has been tested and confirmed by many investigators.
What defines a universal law in science?
A theory that applies universally without exceptions.
True or False: Scientific findings are considered definitively proven.
False.
What is the role of repetition in the scientific method?
Repetition helps verify findings and build trust in observed phenomena.
What can affect the interpretation of scientific studies?
Differences in control and experimental groups, sample size, and cause-and-effect relationships.
Define system dynamics.
The interactions of systems and components within systems.
What is an open system?
A system where the exchange of matter or energy with other systems occurs.
What is a closed system?
A system where no exchange of matter occurs.
How is the Earth system characterized in terms of matter and energy?
Open with respect to energy; closed with respect to matter.
What is an open system?
An open system is one where the exchange of matter or energy between it and other systems occurs.
What is a closed system?
In a closed system, exchange does not occur.
How is the Earth system characterized with respect to energy?
The Earth system is open with respect to energy.
How is the Earth system characterized with respect to matter?
The Earth system is closed with respect to matter.
What are the main areas of human endeavor that influence environmental systems?
- Economics
- Social structures and institutions
- Law
- Policy
- Environmental advocacy and action
What is system analysis?
System analysis involves determining what goes in, what comes out, and what has changed within a given system.
What is a pool in system analysis?
A pool refers to the balance or amount of a substance within a system.
What are inputs and outputs in the context of system analysis?
- Inputs: Additions to the system
- Outputs: Expenditures or withdrawals from the system
What is net flux?
Net Flux = Inputs – Outputs
What does steady state mean in a system?
Steady state means that input equals output and the size of the pool does not change over time.
Give an example of a system that is in steady state.
The water in the atmosphere is an example where input from evaporation equals output as precipitation.
What happens when a resource is decreasing in a system?
It indicates that the system is not being utilized sustainably.
What is accumulation in the context of environmental systems?
Accumulation refers to the rate at which a system is gaining material.
What is depletion in environmental systems?
Depletion refers to the rate at which a system is losing material.
What is a feedback in environmental systems?
Feedbacks are adjustments made by a system in response to behavior or events.
What is a negative feedback loop?
A negative feedback loop is where behavior brings the system variable back to a starting point.
What is a positive feedback loop?
A positive feedback loop continuously moves the system variable away from the stable point.
What is overshoot in system dynamics?
Overshoot is exceeding the stable set point of a system due to delays in response.
Define a population in environmental science.
A population is a group of individuals of a single species.
What are the inputs and outputs that control population size?
- Inputs: Births, Immigration
- Outputs: Deaths, Emigration
What is the formula for net population change?
Net Population Change = Input (Births + Immigration) – Output (Deaths + Emigration)
How can abiotic factors regulate a population?
Abiotic factors can impact the availability of resources, influencing birth and death rates.
What is an example of a negative feedback mechanism in a predator-prey system?
In a wolf-deer system, increased predation as prey increases drives the prey population back down.
What is the current estimated human population on Earth?
Approximately 8 billion people.
How has the rate of human population growth changed since the 1960s?
The rate of growth has been steadily decreasing.
What is the estimated background rate of extinction?
Two mammal species per 10,000 species per one hundred years.
How many species are estimated to be going extinct each year?
Perhaps as many as 40,000—maybe more.
What significant environmental event are we currently in?
A sixth mass extinction event.
What has caused the increase in atmospheric concentrations of carbon dioxide?
Human activity.
What has been the trend in global temperatures since the 1900s?
Global temperatures have risen, with a rapid increase since 1980.
What effect do stricter pollution regulations have on emissions?
Emissions decreased after the early 1970s in the U.S.
What is sustainability?
The consumption of resources in the present that allows an adequate supply to remain for future generations.
What factors influence the environmental impacts of resource consumption?
The number of people and the type and quantity of resources they use.
What is a system in environmental science?
A set of living and nonliving components connected in such a way that changes in one part affect the other parts.
What are open and closed systems?
Open systems exchange matter, energy, or both; closed systems do not.
What is a system analysis?
Determines what goes in, what comes out, and what has changed within a given system.
What does mass balance analysis calculate?
Inputs and outputs to the system pool and the rate of flux through the pool.
What indicates a system is in steady state?
No overall change to the pool.
What is negative feedback in a system?
Changes in the system variable bring the system back to its stable set point.
What is positive feedback in a system?
Changes in the variable lead to further changes, bringing the system further away from the set point.
What can happen if there is too long a delay in a feedback system?
The system may experience overshoot.
What can overshoot lead to in some systems?
Exceeding the carrying capacity.
Fill in the blank: Biological diversity gives a negative indication of the state of the Earth and shows that we are in a _______.
sixth mass extinction event.
