INB 373 Exam 1

Tundra

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ polar (canda, greenland, russia)

2. temperature→ cold

3. precipitation→ wet or dry

4. vegetation→ no trees, small woody plants

5. diversity→ low

6. fire→ rare

7. human uses/threats→ climate change thawing permafrost— oil and gas extraction

Boreal Forests

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ above 50 deg N but south of Tundra

2. temperature→ cold (freezing half year)

3. precipitation→ wet or dry (permafrost maintains high water availb)

4. vegetation→ coniferous trees

5. diversity→ low

6. fire→ common

7. human uses/threats→ lumber, thaw permaforst GW

Temperate evergreen forest

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ 30-40 degrees N,S (western WA, OR, SE, Australia)

2. temperature→ cold winter and warm summers

3. precipitation→ variable (characterized by low nutrient status

4. vegetation→ coniferous trees

5. diversity→ low

6. fire→ common

7. human uses/threats→ beautiful hiking

Temperate deciduous forest

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ 30-50 deg from equator (mostly N hemisphere)

2. temperature→ cold winter, warm summers

3. precipitation→ year round percp, more than grasslands

4. vegetation→ cold-deciduous broad-leaved trees

5. diversity→ moderate

6. fire→ rare (higher moisture)

7. human uses/threats→ logging, urbanization, agriculture

Temprate Scrubland and Woodland

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ California and mediterranean

2. temperature→ seasonal

3. precipitation→ wet in winter

4. vegetation→ shrubs, grasses, trees (no multilayer forest)

5. diversity→ moderate to high

6. fire→ common

7. human uses/threats→ grazing, agriculture, urbanization

Temperate grassland

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ 30-50 deg from equator (OK, TX, Australia)

2. temperature→ intermediate

3. precipitation→ intermediate

4. vegetation→ grasses and herbs (forbs), very few woody plants

5. diversity→ moderate

6. fire→ common

7. human uses/threats→ agriculture !!

Desert

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ 30 deg N/S (Australia, Sahara, Arizona)

2. temperature→ hot

3. precipitation→ little

4. vegetation→ succulents, annual herbaceous plants

5. diversity→ low to moderate

6. fire→ rare (not enough vegetation to keep fire going)

7. human uses/threats→ grazing, recreation, urbanization

Tropical seasonal forest + Savanna

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ 20 deg N/s (close to edge of tropics— Costa Rica, South Africa)

2. temperature→ hot

3. precipitation→ seasonal, heavy rains when ITCZ passes overhead

4. vegetation→ drought-deciduous trees, savanna-continuous grass layer with trees

5. diversity→ moderate to high

6. fire→ common

7. human uses/threats→ grazing and agriculture

Tropical rainforest

1. geographical location

2. temperature

3. precipitation

4. vegetation

5. diversity

6. fire

7. human uses/threats

1. geographical location→ near the equator

2. temperature→ hot

3. precipitation→ lots

4. vegetation→ broadleaf evergreen trees

5. diversity→ high

6. fire→ rare (high humidity)

7. human uses/threats→ logging, agriculture, grazing

define nitrification and denitrification

nitrification→ biological process where ammonia is converted to nitrate

• ammonium converted to nitrite then to nitrate all by bacteria

• provides nitrate for plant uptake

denitrification→ biological process where nitrate reduced to nitrogen bass or nit-oxide

• removed nitrogen from ecosystem by bacteria

permafrost

→ permanently frozen ground for 2+ years, mainly in polar regions

• thawing permafrost releases GHG from decomposing organic matter

• stores tons of carbon

• maintains ecosystem water flow

eutrophication

→ the excess of enrichment of water bodies with nutrients

• nitrogen and phosphorus abundance

• leads to oxygen depletion

• how? agriculture runoffs, sewage, industrial waste, detergents

**a natural process but still influenced by humans

State 3 Micro-evolution forces critical to ecology

1. Genetic drift: random changes in allele frequencies in populations

   • Larger effect on smaller populations→ fixation of bad alleles

2. Gene flow: introduction of new alleles through movement of organisms

   • Ex. 1980s Africa mosquitos became immune to pesticides and resistance spread

3. Natural selection: ecological selective pressures and adapting to new environments

   • Ex. pocket mice and volcanic eruption

positive feedback loop of global temperature rise

1. increased GHG’s like CO2 increased global temps

2. polar ice caps melting

3. less ice reflecting sunlight

4. less heat back to atm/space

5. more uptake of radiation by darker ground and water→ Earth temp increased

Freshwater zones

• photic (light) zone→ upper layer where sunlight penetrates so supports photosynthesis

• aphotic (dark) zone→ deeper layer without sunlight, so low light and low oxygen (organic sinking)

• benthic zone→ bottom sediment layer, home to decomposers like bacteria

Marine Zones

• nearshore (coastal)→ shallow water, rich in biodiversity (nursery) so high productivity w/ nutrient flow from inland

• benthic (seafloor)→ shoreline to ocean trenches, home of coral, crab, deep-sea-fish, critical for decomp

• pelagic (open water)→ supports free-swimming organisms (fish, jellyfish, whales)

  • photic and aphotic zones

identify a temperature and precipitation graph of biomes

identify pools of carbon in organic and inorganic matter

• organic

  • living organisms (macromolecules)

  • detritus (dead living matter)

  • fossil fuels

• inorganic

  • CO2 in air/water

  • bicarbonate ion and carbonate ions is water

nitrogen cycle

1. nitrogen in air becomes fixed in bacteria/frankia and used by plants

   • lightening can also introduce nitrogen to soil

2. herbivores eat plants→ carnivores eat herbivores

   • detrivores eat nitrogen from soil and are also eaten by carnivores

3. detritus take in nitrogen by death, waste, decomp, and nitrification

4. denitrification and burning fossil fuels relased nitrogen back into air

Guilds vs Functional group

• guild→ species with similar roles in an ecosystem but different morphology

  • ex. nectar-feeders like hummingbirds and butterflies

• functional group→ species that have a similar function in an ecosystem and same morphology (look alike)

  • ex. grassland grasses all perform photosynthesis

keystone vs foundation species

• keystone→ disproportionate impact on ecosystem compared to abundance

  • fewer in # but sig control

  • ex. sea otters (control urchin pop)

• foundation→ important species in food web bc of high number

  • lots in # so usually primary producers

  • ex. grass eaten by bison

**keystone species CANNOT be a foundation species and vice versa

types of food chain controls

• bottom-up: amount of biomass is controlled by limited resources

  • GPP/NPP dependent

• top-down: top predators control food web

  • more common

  • ex. sea otter, urchins, and kelp relationship

Trophic Cascade

→ change in the population of a top predator in a food web indirectly impacts the abundance of species at lower trophic levels

ex. sea otters

Pools vs. Fluxes

• pools of matter→ compounds for a certain area

• flux→ how pools move from one form to another

carbon pools and fluxes

pools→ atm, oceans, fossil fuels, biomass, soils

fluxes→ photosynthesis, respiration, combustion, ocean exchange

nitrogen pools and fluxes

pools→ atm (largest), soil, biomass, water

fluxes→ nitrogen fixation, decomp, denitrification

phosphorus pools and fluxes

pools→ rocks (largest), soil, water, organisms

fluxes→ volcanic eruptions, fossil fuel combustion, decomp

GPP & NPP

GPP→ total photosynthesis area/unit time

NPP→ energy available to herbivores and detrivores/unit time (left over after plant uses E)

Global Circulation cells (3)

• hadley cells→ transports warm air from equator to 30o latitude, air rising to poles cools creating trade winds

• ferrel cells→ 30o-60o movies air in the opposite direction to transfer heat poleward

• polar cells→ circulate cold air from poles toward lower latitudes to complete global winds system

coriolis effect

→ phenomenon due to Earth’s (axis) rotation impacting ocean currents, atm circulation, weather systems, migration, climate

define ecology

→ scientific study of interactions between organisms and their environment

outline the levels of ecology (7)

• environment→ abiotic factors (air, water, detritus/waste, minerals)

• organismal→ single biotic

• population→ group of same species interact with each other

• community→ two species interacting (all biotic)

• ecosystem→ at least two biotic and one abiotic factor interact

• landscape→ multiple ecosystems

• global→ all ecosystems in planet

detrivores

→ eat detritus (waste) for energy

ex. earthworm