Lecture 9 Flashcards
Climate & Biomes
________% of Earth’s total global water is fresh water, but most of it is ________ or ________.
2.5%, frozen (glaciers, ice caps, permafrozen), underground
shallow vs. deep coral reefs
- shallow coral reefs are a natural barrier from storms, and home corals and symbiotic algae (Zooxanthellae)
- deep sea reefs build slower due to a lack of algae, and are found in colder, deeper waters
lotic vs. lentic systems
- lotic system (flowing water): water flows consistently in one direction, with an upstream and downstream driven by gravity (flowing water; e.g. rivers)
- lentic system (still water): water flow varies over time due to wind and temperature, with no fixed direction (e.g. wetlands, ponds)
permafrost
frozen soil
Coral reefs are part of the ________ system.
neritic
the Great Ocean Conveyor Belt
the global system of deep-ocean currents
climograph of major biomes in North America
- annual precipitation and temperatures dictate where most terrestrial biomes are found, but some biomes can overlap
- which biome is present depends on disurbances
the five divisions of lakes
divided based on water depth and light level
- littoral zone: shallow waters along the shoreline
- limnetic zone: offshore waters
- benthic zone: bottom of the lake
- photic zone: areas that receive light
- aphotic zone: areas that don’t receive light
ocean gyres
large circulating ocean currents, driven by surface winds (and hence, insolation and the Coriolis effect)
Hydrothermal vents are part of the…
deep sea
the impact of water speed on oxygen and nutrient availability
- fast water is more oxygenated, but less nutrients accumulate near the shore
- slow water is less oxygenated, but more nutrients accumulate near the shore
________ are the largest ecosystem.
Oceans
the impact of topography on climate
- as air rises over a mountain, it cools, releasing moisture as precipitation
- as air descends down a mountain, it warms, taking up moisture
________% of Earth’s surface is covered in saltwater, with ________% of all water found in oceans.
71%, 96.5%
The benthic zone is often rich in…
nutrients
the direction of surface waters
- surface winds push surface ocean currents around Earth
- water currents move heat away from the equator, as water carries more heat than air
rain shadow
a patch of land that is dry due to being covered (e.g. via mountains) during precipitation
biome
broad, ecologically uniform area whose characteristic species reflect regional climate
Intertidal zones are part of the ________ system.
neritic
climate vs. weather
- climate is long-term average weather, determined by solar radiation, global patterns of wind/ocean circulation, and topography
- weather is current conditions (temperature, rainfall, etc.) of an area
the impact of abiotic conditions on evapotranspiration
- evaporation is higher in warmer soil
- transpiration is low in arid environments (lack of water)
the six divisions of lakes
divided based on water depth and light level
- intertidal zone: beach exposed to air at low tide, but underwater at high tide
- neritic zone: from intertidal zone to a depth of 200 m (edge of the continental shelf)
- pelagic zone: open ocean beyond continental shelf
- benthic zone: bottom of the ocean
- photic zone: areas that don’t receive light
- aphotic zone: areas that don’t receive light
the impact of nutrient availability on primary production in marine biomes
- primary production is highest in coastal areas and areas of upwelling
- primary production is lowest in central ocean gyres with little nutrients
terrestrial biome
- large terrestrial communities defined by the dominant vegetation type which is largely based on abiotic conditions (e.g. climate, soil)
- plants can have similarities due to shared history (divergent evolution) or independent evolution (convergent evolution)
the Coriolis effect
- the Earth rotates at the equator faster than at higher latitudes; this rotation causes the bending of winds and waters
- winds bind to the right in the Northern hemisphere, and bind to the left in the Southern hemisphere
the impact of tides on intertidal zones
- rocky shores have narrow littoral zones with compressed zones (organisms attach to rocks)
- sandy shores have wider littoral zones (organisms survive by burrowing in substrate or moving with the tide)
upwelling
- deep, cold water rises to the surface, bringing its nutrients with it
- occurs when winds blow parallel to the coastline, pushing surface waters away from the coast
the most important factor to determine the type of terrestrial biome
water availability (plays a role in the dominant vegetation type)
ten major terrestrial biomes
- tundra
- alpine
- boreal (tiaga) forests
- temperate coniferous forests
- deciduous forests
- temperate grasslands
- deserts
- temperate shrublands and woodlands (chaparral)
- tropical seasonal forests/savannas
- tropical rainforests
three major challenges for organisms living in intertidal zones
- waves
- dessication
- extreme temperatures
Aquatic biome distribution is impacted by… (in order)
- sunlight availibility (very limiting)
- nutrient and oxygen availibility
- water depth and climate (water is not limiting)
the most diverse oceanic biome
coral reefs (home 25% of all fish species)
the impact of thermohaline circulation on water density
- thermo-: hot water is less dense than cold water
- -haline: fresh water is less dense than saltwater
the impact of climate on primary production in terrestrial biomes
global patterns of precipitation and evapotranspiration are similar to global patterns of primary production
- primary production is highest in warm, wet, tropical climates
- primary production is lowest in cold, dry climates
evapotranspiration
- water vapour that enters the atmosphere as evaporation directly from the soil or bodies of water, and as transpiration from plants
- evapotranspiration rates are higher in warm, moist climates
- the ratio between precipitation and evapotranspiration is a major determinant of the dominant vegetation type
the Coriolis effect and hurricanes
- in the Northern hemisphere, hurricanes spin counter-clockwise; winds moving towards the storm’s eye deflect to the right, causing the spin
- in the Southern hemisphere, hurricanes spin clockwise; winds moving towards the storm’s eye deflect to the left, causing the spin
