ENVS Final Exam

Three potential destinations of precipitation

• runoff

• reabsorption by plants

• underground (groundwater)

BOD - what causes it to increase vs decrease?

Biochemical oxygen demand: a measure of how much oxygen is needed to break down organic matter (amount of which causes changes) in water

Greenhouse Effect

Part of global warming - describing the warming of the planet → CO2 acting as a greenhouse for the earth

A liter of ocean water has how much more H as a liter of ammonia? How many times higher?

• hydrogen concentration is -10 power

• 1000 times higher

Nitrogen fixation

convert stable nitrogen to a usable form of nitrogen.

The gas that can cause respiratory harm if breathed but can be a helpful barrier when it remains in the stratosphere

Ozone / o3

Population growth conditions

• birth rate > death rate - population growth

• high life expectancy

• positive net migration

Soil erosion

The gradual wearing away of the top layer of soil - caused by natural forces (water, air, etc) and human activities (farming)

Soil degradation

The decline of soil quality due to natural forces (animals, water, etc) or human activities (farming)

Principles of toxicology

• 'Dose Makes the Poison'

• 'No Agent Has a Single Effect'

• 'Toxic Response is Dependent Upon the Exposed Individuals + Species'.

• Smoking Gun Clause!

Food web

An interconnection of food chains forming complex webs of feeding relationships.

Carp…

produce a lot of waste and bacteria, which will deplete oxygen in the water

Uses of U-235 and U-238

Different isotopes of uranium

• Uranium-235: used in nuclear power plants and weapons

• Uranium-238 is used in breeder reactors

222Rn source and risk

Source: ground → natural decay of uranium 238 in soil and bedrock

Risk: increase health risks (lung cancer)

Guideline used in workplaces to protect workers from adverse health effects from exposure to toxicants

TLV-TWA

Guideline for AEGL and what it is used for

Acute Exposure Guideline Levels (Public Exposure Guideline) → designed to reduce health risks to the general public/sensitive people following exposure to a toxicant from major spill/release

PM2.5

Pollutant in NAAQS

The primary reason for good health and low incidence of bacterial infection in developed countries

unsafe drinking water

What causes anaerobic conditions?

Occur when dissolved oxygen (DO) is depleted due to high biochemical oxygen demand (BOD) → can happen b/c of pollutants have high BOD values

We don’t have to be concerved abt carincogens in drinking water b/c…

low concentration is regulated

Agricultural runoff are most likely cause of…

harmful algal blooms

Equation that determines level of risk in environmental health

Risk = hazard x vulnerability/exposure

Who monitors transmission of bird flu

The WHO and CDC

Global life expectancy trend over past 50 years has…

increase more than 20 years due to modern medicine

Greatest world killer according to WHO

poverty

What do hydroxyl radicals in the atmosphere do in the troposphere?

primary cleansing agent that removes common pollutants

What is the atmospheric brown cloud over much of the south and central Asa?

layer of pollution (black carbon + soot) that occurs year-round

What happens to atmospheric nitrogen when fossil fuels are burned at high combustion temps?

reacts with oxygen to form nitrogen oxides, which contributes to smog + acid rain

What part of the body COPD affects

lower resp system → the airways/passageways + alveoli of the lungs

A truck driver is most likely to be exposed to…

benzene aside from people who smoke tobacco

Effects of acidification on lakes + what results

• decline in fish pop → affects entire aquatic food chain

• be clear, blue, and have higher levels of metals

What size particulate matter has the greatest impact on human health

PM2.5 → smallest particulate matter

Two toxic agents that catalytic converters remove in cars…

• carbon monoxide

• nitrogen oxide

Who is most likely to develop cataracts?

farmer in Texas

CFCs contribute to the destruction of the ozone by…

breaking down in the stratosphere releasing chlorine atoms → one chlorine atom can destroy thousands of ozone molecules

pH of pure rain

5.6

Deductive vs Inductive reasoning

• Deductive → top down idea: that because we know this then we know this – large factual information  

• Inductive → bottom up idea: taking small piece of information to generalize something – i observed this so it must apply to a broader population 

Safe Drinking Water Act protects public from…

unsafe drinking water (aka public water supplies)

Dangerous indoor air pollutants

cigarettes, radon, formaldehyde, asbestos, etc

Denitrification + what happens in that step of the N cycle

microbial process → reactive N from detritus + wastes are converted back to N2 gas by bacteria

Spheres in the Phosphate Cycle

Involved: lithosphere, hydrosphere, biosphere

NOT involved: atmosphere

Most carcinogens

tobacco

If someone smokes in you house, everyone has an increased chance of…

cancer