Environmental Science Exam 1

Describe how photosynthesis works

(water + CO2 + energy -> glucose + O2)

The Vanishing Oysters of Chesapeake Bay

1. Nitrogen and phosphorus input 2. Phytoplankton flourish @ the surface 3. Dead phytoplankton and their waste drift to the bottom, providing more food for bacteria to decompose 4. Microbial decomposer population grows and consumes more oxygen 5. Insufficient oxygen suffocates oysters and grasses, fish and shrimp at the bottom; dead zone (hypoxic zone) forms

Variables

1. scientists use a control to assess the influence of potential factors, called variables 2. conditions stay the same in the control in comparison to the variable condition

Natural

A natural cause (mechanism) must be used to explain why or how the naturally occurring event happens. Scientists may not use supernatural explanations as to why or how naturally occurring events happen because reference to the supernatural is outside of the realm of science.

Ecosystem

All interacting living and nonliving matter in a region

Ecosystem Services

Arise from the normal functioning of natural services and allow us to survive Examples: Purify air and water, cycle nutrients, regulate climate, pollinate plants, recycle waste

Major Component of: Carbon cycle: Nitrogen cycle: Water cycle: Phosphorous cycle:

Carbon cycle: CO2 Nitrogen cycle: N2 Water cycle: Phosphorous cycle: PO4^3-

Particle: Neutron Charge: Location:

Charge: Neutral Location: inside nucleus

Particle: Electron Charge: Location:

Charge: negative Location: outside nucleus

Particle: Proton Charge: Location:

Charge: positive Location: Inside the nucleus

CONPTT stands for

Consistent Observable Natural Predictable Testable Tentative

Human Impact on the (hydrologic cycle) water cycle

Damming rivers increases evaporation and can cause infiltration of surface water into aquifers. Altering vegetation increases surface runoff and erosion. Agricultural irrigation depletes water sources and increases evaporation. Climate change increases evaporation and the water holding capacity of the air Rainfall intensity is increased Droughts are intensified because evaporation occurs more quickly

Laws of Thermodynamics 1st Law:

Energy cannot be created nor destroyed, but can be transformed

Laws of Thermodynamics 2nd Law:

Entropy (state of disorder) always naturally increases.

Environmental Justice

Involves the fair treatment of all people with respect to the environment, regardless of income, race, or ethnicity

Know this: In a positive feedback loop, output acts as input that moves the system further in the same direction.

Know this: This magnification of effects destabilizes the system.

Sustainability

Living within our planet's means Leaving our descendants with a rich, full world by: Conserving resources for future generations Developing solutions that work in the long term Keeping fully functioning ecological systems

Tentative

Scientific theories are subject to revision and correction, even to the point of the theory being proven wrong. Scientific theories have been modified and will continue to be modified to consistently explain observations of naturally occurring events.

Human Impact on the nitrogen cycle

Since chemists devised a way to fix nitrogen artificially, synthetic nitrogen fertilizers have boosted agricultural production. Today we are fixing as much nitrogen artificially as the nitrogen cycle does naturally.

Ecological Footprint

The area of biologically productive land and water to provide resources and dispose/recycle waste

Observable

The event under study, or evidence of the occurrence of the event, can be observed and explained. If the phenomenon cannot be reproduced through controlled conditions, natural evidence of the event's occurrence must be available for investigation.

Predictable

The natural cause (mechanism) of the naturally occurring event can be used to make specific predictions. Each prediction can be tested to determine if the prediction is true of false.

Testable

The natural cause (mechanism) of the naturally occurring event must be testable through the processes of science, controlled experimentation being essential. Reference to supernatural events or causes are not relevant tests.

Consistency

The results of repeated observations and/or experiments concerning a naturally occurring event (phenomenon) are reasonably the same when performed and repeated by competent investigators.

True or False: Humans are currently using the earth's resources and services at a rate that cannot be sustained over time.

True

How are we impacting our environment?

We are using renewable resources 50% faster than they are being replenished!

Human Impact on the Carbon Cycle

We have increased CO2 in the atmosphere by burning fossil fuels and deforesting. Atmospheric CO2 concentrations may be higher now than they have been in the last 420,000 years. This is driving global warming and climate change.

Human Impact on the phosphorous cycle

We mine rocks containing phosphorus for inorganic fertilizers for use on crops and lawns. Treated and untreated sewage discharge contains phosphates, as do some detergents. Phosphates that run off into waterways cause eutrophication, altering the structure and function of aquatic ecosystems.

Negative Feedback loop

a circular process whereby a system's output serves as input to that same system

An ethical worldview that focuses on rivers, plants and animals would be? a. Anthropocentric b. Ecocentric c. Biocentric d. Lemnicentric

b. Ecocentric

Which of these describes nitrogen fixation a. The formation of hydrogen gas from methane b. The transformation of nitrogen gas into Ammonium ions c. The transformation of nitrate ions into nitrogen gas d. The transformation of ammonia into nitrates

b. The transformation of nitrogen gas into Ammonium ions

A hypothesis is ________. a. a prediction about something that has not yet been observed b. a testable proposition that explains an observed phenomenon or answers a question c. a proven scientific fact d. the design of an experiment that can be used in scientific enquiry

b. a testable proposition that explains an observed phenomenon or answers a question

An example of a positive feedback loop is ________. a. a pond becoming more acidic as a result of pollution b. melting arctic snow exposing dark surfaces that heat up and cause further melting c. predators eating most of their prey and then declining in numbers d. a thermostat turning on the furnace as temperature drops

b. melting arctic snow exposing dark surfaces that heat up and cause further melting

River water held behind a dam is best described as a form of ________. a. kinetic energy b. potential energy c. chemical energy d. entropy

b. potential energy

Today (2019), there are about ________. a. 10 billion people on Earth b. 5.35 billion people on Earth, the same as for the past 6 years c. 9 billion people on Earth d. 7.5 billion people on Earth

d. 7.5 billion people on Earth

As permafrost warms it releases more methane and CO2 which increases planetary warming which in turn melts more permafrost. This is an example of? a. A negative feedback loop b. Tragedy of the commons c. A biological process d. A positive feedback loop

d. A positive feedback loop

Which of these is the stage of the scientific process that comes after a peer review that was unsuccessful? a. Writing a scientific paper b. Publication in a scientific journal c. Experiment to test hypothesis d. Rejection followed by revision of paper

d. Rejection followed by revision of paper

Kinetic energy & example

energy of movement (rushing water released from a dam)

Potential energy & example

energy of position ex. (water held behind a dam)

Hypothesis

is a proposition concerning the natural world that can be tested

Chemical Energy & example

potential energy held in the bonds between atoms (hydrocarbons of gasoline splitting to generate motion)

The nitrogen cycle

• Atmospheric N2 is fixed by lightning or specialized bacteria and becomes available to plants and animals in the form of ammonium ions (NH4+). • Nitrifying bacteria turn ammonium ions into nitrite (NO2-) and nitrate (NO3-) ions. Nitrate can be taken up by plants. • Animals eat plants, and when plants and animals die, decomposers consume their tissues and return ammonium ions to the soil. • Denitrifying bacteria convert nitrates to gaseous nitrogen that reenters the atmosphere.

The phosphorus cycle

• P is most abundant in rocks. Weathering releases phosphate (PO43- ) ions from rocks into water. • Plants take up phosphates in water, pass them on to consumers, who return them to the soil when they die. • Phosphates dissolved in lakes and oceans precipitate, settle, and can be incorporated into sedimentary rock.

The carbon cycle

• Producers pull carbon dioxide (CO2) from the air and fix it into organic compounds. • Consumers eat producers and return CO2 to the air by respiration. • Decomposition of dead organisms plus pressure underground forms sedimentary rock and fossil fuels. • Ocean water absorbs carbon storing it in sedimentary rock or providing it to aquatic plants.

The hydrologic cycle

• Water enters the atmosphere by evaporation and by transpiration from leaves. • It condenses and falls from the sky as precipitation. • It flows as runoff from the land surface into streams, rivers, lakes, and eventually the ocean. • Water infiltrates into aquifers, becoming groundwater, the upper limit of which is the water table.

The SECOND law of thermodynamics is . . . a. Things tend toward disorder and energy must be expended to create order b. Energy is stable c. Energy cannot be created or destroyed d. Potential energy is more powerful than kinetic energy

a. Things tend toward disorder and energy must be expended to create order