apes all chapters

Producer/Autotroph

organisms that make their own food. Photosynthetic life (plants).

Trophic Levels in Food Chains

producers → primary consumer → secondary consumer → tertiary consumer.

Photosynthesis

plants convert CO2 (atmospheric carbon) into complex carbohydrates (glucose C6H12O6).

Equation for photosynthesis

CO2 + H2O + sunlight → C6H12O6 + O2

Respiration (Aerobic)

oxygen consuming producers, consumers & decomposers break down complex organic compounds & convert organic carbon back into CO2.

Equation for respiration

C6H12O6 + O2 → CO2 + H2O + energy

Energy Flow through Food Webs

Only about 10% of usable energy is transferred from one trophic level to the next. Reason: usable energy lost as heat (2nd law of Thermodynamics), not all biomass is digested & absorbed, predators expend energy to catch prey.

Biotic

the living components of an ecosystem.

Abiotic

the nonliving components of an ecosystem.

CHNOPS

Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorous, Sulfur (mnemonic for the six most abundant elements in living organisms). Each is part of important biogeochemical cycles.

Nitrogen Fixation

atmospheric nitrogen (N2), which cannot be used directly by plants, is first converted into ammonia by bacteria.

Nitrification

ammonia is converted to nitrate ions (NO3-).

Assimilation

inorganic nitrogen (nitrate) is converted into organic molecules such as DNA/amino acids & proteins. (uptake)

Ammonification

decomposers convert organic waste into ammonia.

Denitrification

bacteria convert ammonia into atmospheric nitrogen (N2).

Phosphorus

does not exist at the Earth's surface as a gas; released into ecosystems through the weathering of phosphate rocks, it is a major limiting factor for plant growth. The phosphorus cycle is relatively slow, without an atmospheric step.

Primary succession

development of communities in a lifeless area not recently inhabited by life (ex. lava flow, retreating glacier).

Secondary succession

life progresses where soil remains (ex. clear-cut/burned forest, old farm, vacant lot).

Mutualism/Symbiosis

symbiotic relationship where both organisms benefit.

Commensalism

symbiotic relationship where one organism benefits & the other is unaffected.

Parasitism

relationship in which one organism (the parasite) obtains nutrients at the expense of the host.

Carrying Capacity

the number of individuals that can be sustained in an area.

r-strategist

reproductive strategy in which organisms reproduce early, bear many small, unprotected offspring (ex. insects, mice).

K-strategist

reproductive strategy in which organisms reproduce late, bear few, and care for offspring (ex. humans, elephants).

Natural Selection

organisms that possess favorable adaptations pass them onto the next generation.

Humus

organic, dark material remaining after decomposition by microorganisms.

Loam

perfect agricultural soil with equal portions of sand, silt, and clay.

Leaching

the removal of dissolved material from soil by water as it moves downward (percolates) through soil.

Soil Conservation

Methods include conservation tillage, crop rotation, contour plowing, terracing, windbreaks, no-till.

Soil Salinization

in arid regions, water evaporates leaving salts behind. (ex. fertile crescent, southwestern US)

Waterlogging

water completely saturates soil starves plant roots of oxygen, rots roots

Watershed

all of the land that drains into a body of water.

Aquifer

underground layers of porous rock allow water to move slowly.

Saltwater Intrusion

near the coast, overpumping of groundwater causes saltwater to move into the aquifer.

ENSO

El Nino Southern Oscillation, trade winds weaken & warm surface water moves toward South America. Diminished fisheries off South America, drought in western Pacific, increased precipitation in southwestern North America, fewer Atlantic hurricanes.

La Nina

A "normal" year, easterly trade winds and ocean currents pool warm water in the western Pacific, allowing upwelling of nutrient rich water off the West coast of South America.

Doubling Time (rule of 70)

the doubling time is equal to 70 divided by the percent rate of growth. (ex. a population growing at 5% annually doubles in 70 ÷ 5 = 14 years)

Replacement Level Fertility

the number of children a couple must have to replace themselves (averages 2.1 in more developed nations, 2.7 in less developed nations).

World Population

approximately 7.9 billion (in 2022)

US Population

approximately 335 million. (in 2022)

Preindustrial stage

birth & death rates high, population grows slowly, infant mortality high.

Transitional stage

death rate (infant mortality) lower, birth rates remain high, better health care, population grows fast.

Industrial stage

decline in birth rate, population growth slows.

Post Industrial stage

low birth & death rates.

Age Structure Diagrams

broad base = rapid growth; narrow base = negative growth; uniform shape = zero growth

Most Populous Nations

(1) China; (2) India; (3) U.S.; (4) Indonesia

Composition of Water on Earth

97.5% seawater, 2.5% freshwater.

Aquaculture

farming aquatic species, commonly salmon, shrimp, tilapia, oysters.

Point Source

source from specific location such as pipe or smokestack

Non-Point Source

source spread over an area such as agricultural/feedlot runoff, urban runoff, traffic.

Eutrophication

rapid algal growth (algal bloom) caused by an excess of nitrogen & phosphorus (phosphorus usually limits), blocks sunlight, causing the death/decomposition of aquatic plants, decreasing dissolved oxygen (DO), suffocating fish.

Hypoxia

water with very low dissolved oxygen levels, the end result of eutrophication, for example.

Primary Sewage Treatment

first step of sewage (wastewater) treatment; eliminates most particulate material from raw sewage using grates, screens, and gravity (settling).

Secondary Sewage Treatment

second step of sewage treatment; bacteria break down organic waste, aeration accelerates the process.

Tertiary Sewage Treatment

final step of sewage treatment; ponds/wetlands used to remove nutrients nitrogen & phosphorus.

BOD

Biological Oxygen Demand, amount of dissolved oxygen needed by aerobic decomposers to break down organic materials.

Turbidity

a measure of the cloudiness of water, caused by suspended solids (sediment).

Water Hardness

the result of dissolved calcium ions (Ca2+) and magnesium (Mg2+).

CAFE standards

Corporate Average Fuel Economy standards enacted into law in 1975, established fuel efficiency standards for passenger cars and light trucks. The fuel economy ratings for a manufacturer's entire line of passenger cars must currently average at least 27.5 mpg for the manufacturer to comply with the standard. Revised in 2012 to 54.5 mpg by the year 2025.

Primary Air Pollutants

produced by humans & nature (CO, CO2, SO2, NO, hydrocarbons, particulates).

Secondary Air Pollutants

formed via the atmospheric reaction of primary air pollutants.

Particulate Matter (PM2.5 & PM10)

sources include burning fossil fuels and car exhaust. Effects include reduced visibility, respiratory irritation. Methods of reduction include filtering, electrostatic precipitators, and using alternative sources of energy.

Photochemical Smog

formed by chemical reactions involving sunlight (NOx, hydrocarbons, O2).

Ozone

Secondary pollutant, NO2 + UV → NO + O; O + O2 → O3, with VOCs. Causes respiratory irritation and plant damage. Reduced by reducing NO emissions and VOCs.

Nitrogen Oxides

(NOx) Major source is auto exhaust. Primary and secondary effects include acidification of lakes, respiratory irritation, leads to smog and ozone. Reduced using catalytic converters.

Equation for acid formation: NO + O2 → NO2 + H2O → HNO3 (nitric acid)

Acid Deposition

caused by sulfuric and nitric acids formed from NOx and SOx resulting in lowered pH of surface waters

Sulfur Oxides

(SOx) Primary source is coal burning. Primary and secondary effects include acid deposition, respiratory irritation, plant damage. Reduction methods include: scrubbers, burn low sulfur fuel.

Equation for acid formation: SO2 + O2 → SO3 + H2O → H2SO4 (sulfuric acid)

Carbon Dioxide

(CO2) Sources include the combustion of fossil fuels. Effects: greenhouse gas-contributes to global warming. Reduction accomplished by increased fuel efficiency (gas mileage), mass transit (reduction).

Carbon Monoxide

(CO) Sources include incomplete combustion of fossil fuels. Effects: binds to hemoglobin reducing blood's ability to carry O2. Reduction accomplished by catalytic converters, oxygenated fuel, mass transit (reduction).

Greenhouse Effect

a vital process, required for life to exist on Earth. When accelerated, it leads to global warming.

Greenhouse Gasses

Most significant (not anthropogenic) - H2O. Also (and largely anthropogenic) - CO2, methane (CH4), and CFCs. Trap outgoing infrared energy (heat) causing earth to warm.

Effects of Global Warming

rising sea level (due primarily to thermal expansion, not melting ice), extreme weather, droughts (famine), and extinctions.

Albedo

The ability of a surface to reflect light. Snow reflects more light than rock.

Ozone Depletion

caused by CFCs, methyl chloroform, carbon tetrachloride, halon, methyl bromide all of which attack stratospheric ozone. Negative effects of ozone depletion include increased UV, skin cancer, cataracts, and decreased plant growth.

Municipal Solid Waste

is mostly paper and mostly put into landfills.

Sanitary Landfill

problems include leachate, which is solved using a liner with a collection system; methane gas, which may be collected and burned; and the volume of garbage, which may be compacted and/or reduced.

Incineration

Advantages-volume of waste reduced by 90% and waste heat can be used. Disadvantages-toxic emissions (polyvinyl chloride, dioxin), scrubbers and electrostatic precipitators needed, ash disposal.

Reduce

The best solution for the solid waste problem is to reduce the amount of waste at the source.

Reuse

A low tech, low energy solution for the solid waste problem.

Recycle

Superior to landfilling waste. Conserves resources, reduces the need for ongoing mining operations.

Brownfield

an abandoned industrial site.

Remediation

return a contaminated area to its original state.

Keystone Species

species whose role in an ecosystem is more important than others.

Indicator Species

species that serve as early warnings that an ecosystem is being damaged.

Insecticides

chlorinated hydrocarbons (ex. DDT); organophosphates (ex. Malathion); carbamates (ex. Aldicarb)

Pesticide Advantages

saves lives by preventing insect transmitted disease, increases food supply, and increases profits for farmers. Disadvantages: genetic resistance, ecosystem imbalance, pesticide treadmill, persistence in the environment, bioaccumulation, and biological magnification.

Natural Pest Control

better agricultural practices, genetically resistant plants, natural enemies, and biopesticides, sex attractants.

Genetically Modified Organisms (GMOs)

new organisms created by altering the genetic material (DNA) of existing organisms; usually in an attempt to remove undesirable or create desirable characteristics in the new organism.

Electricity Generation

steam, from water boiled by fossil fuels or nuclear energy, or falling water is used to turn a generator.

Petroleum (Crude Oil)

formed as microscopic aquatic organisms in sediments are converted by heat & pressure into a mixture of hydrocarbons. Advantages: cheap, easily transported, high-quality energy. Disadvantages: reserves depleted soon, pollution and land subsidence during drilling, pollution during transport and refining, burning produces CO2.

Coal Formation

prehistoric plants buried un-decomposed in oxygen-depleted water of swamps/bogs converted by heat and pressure.

Ranks of Coal

peat, lignite, sub-bituminous coal, bituminous coal, anthracite coal.

Nuclear Reactor

consists of a core, control rods, moderator, steam generator, turbine, containment building.

Alternate Energy Sources

wind, solar, waves, tides, biomass, geothermal, fuel cells

First Law of Thermodynamics

energy is neither created nor destroyed, but may be converted from one form to another.

Second Law of Thermodynamics

when energy is changed from one form to another, some useful energy is always degraded into lower quality energy (usually heat).

Ionizing radiation

radiation w/enough energy to free electrons from atoms forming ions, may cause cancer (ex. gamma, X-rays, UV).

High Quality Energy

organized & concentrated, can perform useful work (ex. fossil fuels & nuclear).

Low Quality Energy

disorganized, dispersed (ex. heat in ocean or air/wind, solar).

Hydraulic fracturing "fracking "

A technique that pumps pressurized fluids and sand into a well to propagate fractures in the rock and release oil and gas for extraction. Allows for the extraction of previously unavailable or economically depleted petroleum reserves. Controversial because it can contaminate groundwater and release air pollutants.