Lecture 4: The Physical and Chemical Environment-Part 3

Latitudinal

How far north or south of the equator, "diversity" meaning the number of species, and "gradient" meaning the transition between high and low

Elevation

The height of land above sea level

Continentality

Effect of extreme variation in temperature and very little precipitation within the interior portions of a landmass

Microclimate

Climate within a small area that differs significantly from the climate of the surrounding area

Depth

Downward measurement from a surface

Diurnal

Active during the day

Isotherm

Line drawn on a weather map that connects points having equal temperature

Allen's Rule

Mammals living in the cold have shorter faces and limbs than mammals living in warmer areas

Bergmann's Rule

Warm-blooded animals that live in cold areas are bigger than those that live in warm areas

Solar Radiation

Transmission of energy from the sun in the form of electromagnetic waves.

Photons

A quantum, or discrete quantity, of light energy that behaves as if it were a particle.

Chlorophyll a

A photosynthetic pigment that participates directly in the light reactions, which convert solar energy to chemical energy.

Chlorophyll

A green pigment found in the chloroplasts of plants, algae, and some bacteria

Accessory Pigment

Compound other than chlorophyll that absorbs light at different wavelengths than chlorophyll

Photosynthetically Active Radiation (PAR)

Wavelengths of light between 400 and 700 nm that photosynthetic organisms use as a source of energy

Stomata

Small openings on the underside of a leaf through which oxygen and carbon dioxide can move

Photosynthesis

Conversion of light energy from the sun into chemical energy.

Phosphoglycerate

The product of the spontaneous split of an unstable 6-carbon intermediate formed by CO2 fixation.

C3 Photosynthesis

The most common form of photosynthesis in which atmospheric CO2 is used to form 3-phosphoglycerate, a three-carbon sugar.

C4 Photosynthesis

process that first converts CO2 into a 4-carbon molcule in the mesophyll cells, converts that product to malate and then shuttles it to the bundle sheath cells, where the malate releases CO2 and rubisco picks it up as if all were normal

CAM Photosynthesis

The photosynthetic pathway in which carbon fixation takes place at night, and the resulting carbon acids are stored until daylight when they are broken down into pyruvate and CO2.

Hydrosphere

All the water at and near the surface of the earth, 97% of which is in oceans

Lithosphere

A rigid layer made up of the uppermost part of the mantle and the crust.

Biosphere

Part of Earth in which life exists including land, water, and air or atmosphere

Residence Time

The average time a given particle will stay in a given system

Leaches

Water moving down through soil carrying dissolved nutrients with it

Troposphere

The lowest layer of Earth's atmosphere

Stratosphere

The second-lowest layer of Earth's atmosphere.

Ozone Layer

Protective layer in atmosphere that shields earth from UV radiation.

Water Cycle

The continuous process by which water moves from Earth's surface to the atmosphere and back

Carbon Cycle

The organic circulation of carbon from the atmosphere into organisms and back again

Calcifying Organisms

•Corals
•Coccolithophore algae
•Coralline algae
•Foraminifera
•Shellfish
•pteropods

Biogenic Carbonate

Living creatures create calcium carbonate shells

Eutrophication

A process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria.

Chemosynthesis

Process in which chemical energy is used to produce carbohydrates

Primary Producers

The first producers of energy-rich compounds that are later used by other organisms

Gross Primary Production

The total primary production of an ecosystem.

Net Primary Production

The gross primary production of an ecosystem minus the energy used by the producers for respiration.

Secondary Production

Amount of chemical energy in consumers' food that is converted to new biomass.

Herbivores

Consumers that eat only plants

Primary Consumers

Animals that feed on producers; ex. herbivores

Secondary Consumers

Carnivores that eat herbivores

Tertiary Consumers

Carnivores that eat other carnivores

Detritus

Dead organic matter

Detritivores

Feed on plant and animal remains and other dead matter

Saptotroph

Type of decomposer such as a fungus or protozoan that feeds on any remaining organic matter that is left after other decomposers do their work.

Decomposers

Organisms that break down the dead remains of other organisms

Trophic Level

Each step in a food chain or food web

Horizon

A layer of soil

A Horizon

Has much organic matter, including undecomposed plant litter and partially decomposed humus; also contains mineral particles; contains shallow plant roots; highly soluble substances are somewhat depleted by leaching.

Plant Litter

Dead plant material, such as leaves and twigs, that has fallen to the ground.

Leaching

Removal of dissolved materials from soil by water moving downwards

Humus

Material formed from decaying leaves and other organic matter

B Horizon

Contains more mineral matter, including clay minerals formed reactions with bedrock minerals; substances from above often deposited here; contains some humus and plant roots.

C Horizon

Contains primarily weathered bedrock minerals, formed by oxidation or by deposition of evaporites in dry climates; has fewer plant roots.

Evaporites

Sedimentary rocks formed from minerals left after water evaporates

R Horizon

The bedrock, which lies below all of the other layers of soil.