Unit 1 Flashcards
Tundra
Coldest biome. Treeless, permafrost. Found in Russia, Canada, Scandinavia and Alaska. Low precipitation.
Boreal Forest or Taiga
Thick evergreens. Second coldest biome. 50 - 60 degrees north in North America, Europe and Asia
Temperate rainforest
Middle temperature, highest precipitation. Evergreen forests. Redwood forests. Found near warm ocean currents like Pacific coast in North America, southern Chile, New Zealand, Tasmania
Temperate Seasonal Forest
Moderate temperature and precip. Deciduous trees. Maple, beech, oak. Can also be pine forest. Not near an ocean. Eastern US and Canada. Also Europe and Eastern Asia.
Woodlands/shrublands
Moderate temperature, low precipitation. Hot, dry summers and mild, wet winter. Drought tolerant grasses and shrubs dominate. Mediterranean Sea, South America, Africa, Cali.
Temperate grasslands/cold desert
Moderate temperature, lowest precipitation. hot, dry summer and cold, harsh winter. Grasses, nonwoody flowering plants, drought-adapted shrubs. Utah, Colorado, central asia
Tropical Rainforest
Highest precipitation and temperatures. Multiple layers of lush vegetation. Understory, vines, highest species diversity. Central America, Amazon, Congo, Madagascar, Southeast Asia, Australia.
Tropical Seasonal Forests / Savannas
Highest temperature, moderate precip. Occurs 10 degrees N and S. Pronounced wet and dry seasons. Deciduous trees, thorn forest, dry forest, grasslands with occasional trees: acacia and baobab. Central America, South America, Africa, Australia. Good for agriculture
Subtroptropical desert
Highest temperature, lowest precip. Mojave desert, Sahara, Arabian, Great Victoria deserts. Creosote bush, cacti, succulents, shrubs. High species diversity.
What is ecology?
The science of studying organisms and how they interact in and with their physical environment
Who coined the term ecology?
Ernst Haekel
At what levels does an ecologist study?
Organism, population, community, ecosystem, biosphere
What is the fundamental unit in ecology?
The organism
Why is ecological study important?
To determine the best policies for managing our environmental support systems.
To solve or prevent environmental problems
To inform our economic, political and social thought and practice
How are ecological studies performed?
With the scientific model:
Observation, hypothesis or model, prediction, experiment
How do ecologists deal with ecological complexity in their studies?
They create microcosm experiments
What are microcosm experiments?
Experiments used to control certain variables that would be impossible to control in the field. Ex. in a greenhouse or fish tank
What are mathematical models?
Theoretical models used to map and predict natural processes such as population levels. Operates within explicit set of assumptions
What is autecology? Synecology? How does these differ from the other areas of ecological study?
Autecology- Study of individuals and interactions with environment
Synecology- the ecological study of whole plant or animal communities.
They differ in scale
Compare and contrast the following terms: ecology, environmental science, environmentalism, conservation
Ecology- a science, a study
Environmental science- is an applied science with a human focus
Environmentalism- a social and political belief system (human focus)
Conservation biology- a science committed to maintain biodiversity through human use
What constitutes the physical environment?
Light, temp, moisture, nutrients
What is light?
Light is photon radiation, in ecology its from the sun
Why is light an important part of the physical environment?
Because it is the source of energy for the earth. Primary producers are often photosynthetic
What is the nature of light? (i.e., spectral quality, intensity, duration, etc.)?
Spectral quality - Photosynthetically Active Radiation (PAR) 4% UV 44% visible, 54% infrared
Intensity - Solar constant = about 1400 W/m^2
What is the fate of light that reaches the earth’s surface?
Absorption
Reflection
Transmission
- How does light affect photosynthesis?
The more light, the more photosynthesis
- What is the fate of light in an aquatic environment? What is a photic or euphotic zone?
It travels through the euphotic or photic zone, but doesn’t reach past 200 m (Aphotic zone)
- What is heat? What is temperature? Compare and contrast these terms.
Heat- total quantity of kinetic energy of a substance. Depends on size and kinetic energy
Temp - measure of the avg kinetic energy of molecules. Doesn’t depend on size
- What are the modes of thermal energy exchange? Why is the thermal environment important?
Modes: radiation, convection, conduction, evaporation
It affects amount of available water, and how much metabolic energy organisms must produce
- What are the structural and physical properties of water?
structural - hydrogen bonding, 2 H, 1 O. Polar.
Physical- spec. heat 1 cal / 1C / 1 g, cohesion, adhesion, capillarity, viscosity
Why is water an important part of physical environment?
All living things need water to survive. Solvent of life.
- How is water distributed in the biosphere?
Oceans- 97.25%
Ice- 2%
Groundwater- 0.7%
Atmosphere, rivers, lakes, soil moisture- less than .05%
What is the water cycle? Can you trace the water cycle?
Evaporation, condensation, precipitation
no
- What is an adaptation? How does that differ from acclimation?
An adaptation is genetic and its a change that occurs over many generation. Acclimation is a change that occurs within an individual
- What is homeostasis? Explain a negative feedback loop.
The maintenance of a relative internal balance in an organism. A negative feedback loop has sensors that trigger a reaction that counteracts the sensed trigger
- What is PAR? What are plant adaptations to variation in PAR?
Photosynthetically Active Radiation
Adaptation- C3 - plants cannott undergo photorespiration at high temp (Rubisco has 02 affinity at high temp) CO2 transferred to bundle sheath
C4 adaptation high temp
CAM adaptation for high temps and low water
How does the periodicity of light affect plant processes? What are short-day vs. long-day plants?
The length of the day determines when a plant flowers.
Short-day plants flower when days are short
- What is a photosynthetic response curve? Can adaptations to low or high light environments be seen in these curves?
It shows how photosynthetically active a plant is at different intensities of light. Yes, shade tolerant plants reach saturation point sooner than shade intolerant ones
What are C4 and CAM photosynthesis? In what ways do these alternate photosynthetic pathways constitute adaptations? What is PEP carboxylase?
C4 adaptation for high temps. CO2 transported to bundle sheath (O2 and Rubisco seperate)
CAM adaptation for high temp, low water. Stomata remain closed during the day.
PEP Carboxylase imortant in c4 and CAM, binds CO2
- What are plant adaptations to the thermal environment (i.e. high temperatures, freezing temperatures)? For example: What are sunken stomates? What are trichome filled pits? What role do glycoproteins play in freezing avoidance?
Sunken stomates- for dry, high temp environment. Stomates found within pit in leaves
Trichome filled pits - for dry, high temp environment. Sunken stomates with hairs in the pit
Glycoproteins- for freezing temps. They act as antifreeze
- How do plants uptake water? What is adhesion-cohesion theory for water uptake in plants? What is water potential? What is the field capacity of soil? What is the soil matrix potential? What is the permanent wilting point? Available water capacity? How does a root pull water from the soil? How does water move to the top of a tall tree? Describe the water potential differences from soil, root, stem, leaf, atmosphere that would facilitate the movement of water into a root and up the plant to the leaf?
Soil to roots - higher concentration of salts in roots than soil
Stems to leaves- cohesion and adhesion as water evaporates from stomata
Field capacity of soil - When a soil is saturated and gravitational water drains (-.1 atm)
Permanent wilting point - (-15 atm) point at which most plants wither. Soil matrix potential is more negative than plant matrix potential.
Soil matrix potential - how strongly the water is attracted to the soil
atm < leaf < root < soil
- What are plant responses and adaptations to short and long-term variations in water stress? How are root to shoot ratios affected by water stress?
The more water stress, the greater the root to shoot ratio will be.
Adaptations - succulence, reflective surfaces, diffuse leaves, hairy leaves, few leaves, sunken stomata, closed stomata
- What are plant adaptations to flooding or standing water? What are pneumatophores? Aerenchyma?
Flooding - pneumatophores shunt oxygen to roots
pneumatophores- root knees
aerenchyma- plant tissue with air pockets found inside pneumatophores
- What are macronutrients? What are micronutrients? What are plant adaptations for limitations in nutrient availability? How are root to shoot ratios affected by nutrient stress? What is nutrient translocation?
Macronutrients- organisms need a lot of them (CHOPKINS CaFe Mg) (Na,Cl)
Micronutrients- Mn, B, Co, Cu, Mo, Zn, I, Se
Adaptation: more root, less shoot; leaf longevity; nutrient translocation; tolerance
- What is a halophyte? What are the two problems that saline environments pose? What are plant adaptations to high salinity?
Plants adapted to high saline environments.
Osmotic regulation and direct toxicity
Salt exclusion, succulence and salt secretion
- How do animals vary in acquisition of energy and nutrients?
Not sure
- What is a poikilotherm? What are the advantages and disadvantages to being a poikilotherm? What is an ectotherm? What influence does ectothermy have on body size? How do ectotherms respond to high and low temperatures?
Poikilotherm- variable internal temperature
Low energy demand, utilize extreme niches, small elongate bodies, starvation resistance, slow moving in cold
Hibernation
- What is a homeotherm? What are the advantages and disadvantages to being a homeotherm? What influence does homeothermy have on body size? What is an endotherm?
Homeotherm- constant internal temperature
Enzymes for lactate recovery, muscle contraction, oxygen release, advantageous for rapid growth, digestion and movement
endotherm- generates heat internally
- What are some of the temperature adaptations of homeotherms (i.e. gular fluttering, countercurrent heat exchange, retes, torpor, hibernation, etc)? What are some adaptations of animals to the cold environment? Hot environments with moisture stress?
gular fluttering- cooling behavior, birds flap membranes in throat to increase evaporation
countercurrent heat exchange- veins and arteries (retes) pass each other and exchange heat going to the feet
torpor- mild hibernation for one night
hibernation- decrease of metabolic needs for extended periods of time, sleep, lower body temperature
Hot adaptations- nocturnal, burrowing, shade seeking
cold adaptations- insulation, huddling, non-shivering thermogenesis
- What is facultative temperature regulation or facultative endothermy?
Organisms that exhibit both poikilothermic and homeothermic conditions
- What does it mean to be poikilosmotic or homeosmotic? How do marine and freshwater fish deal with osmotic regulation? How do sharks and rays accomplish osmotic regulation?
Sharks and rays- retention of urea makes equal concentration between organism and environment
freshwater fish- lots of urine, gills actively transport solutes in
marine fish- drink lots of water, actively transport solutes out
poikilosmotic - salt concentration varies with environment
homeosmotic - constant salt concentration through regulation
- How does the Kangaroo rat deal with temperature and terrestrial water limitations?
Several adaptation: nocturnal, burrow to low temp and high humidity, no sweat glands, turbinates, highly concentrated urine (3.8x)
What are circadian rhythms? Biological clocks?
Biological clock is the broader term for when you mature, grow, age and die
Circadian rhythm- innate rhythm of activity and inactivity covering about 24 hours
- What is solar radiation? How much solar radiation actually strikes the earth? How much is reflected by atmosphere?
Solar radiation- electromagnetic radiation from the sun
45% absorbed by the earth
29%-30% is reflected by the atmosphere
- What is the greenhouse effect? How does the burning of fossil fuels and depletion of ozone layer contribute to the greenhouse effect?
The greenhouse effect is caused by greenhouse gases in the atmosphere, which reflect electromagnetic radition from the earth off the atmosphere and back to the earth
The burning of fossil fuels introduce more greenhouse gases, and holes in the ozone let in more radiation
- Why don’t the sun’s rays strike the earth uniformly? What is annual insolation? How does it vary across the globe?
Four reasons:
- The earth is a sphere (varying angle of incidence)
- The earth is tilted on its axis
- The earth rotates on its axis
- The earth orbits ecliptically
Annual insolation- The amount of solar radiation an area receives in a year
Equator has highest insolation, decreasing steadily towars the poles
- Why do we have pronounced seasonality at high latitudes? What causes this seasonality?
That’s where seasonal solation varies the most due to the tilt of the earth
- Why do we have circulation of heat energy from equatorial regions to the poles?
Because of the temperature differential, the air moves from high pressure high temp to low pressure low temp
Who was George Hadley and what did he propose regarding thermal circulation?
George Hadley proposed that the temperature differential between poles and equator would create two large convection cells
What is a Hadley cell? What are the names of the circulation cells as you move from equator to the poles?
Hadley cells are the convection cells along the equator
Hadley, Ferrel, Polar
- What are the prevailing winds? What determines the direction of these winds (easterlies and westerlies)? At what latitudes do we find these different winds? What determines the strength of these winds?
NE Trades, SE Trades
(0-30), Mid-latitude westerlies (30-60), Polar easterlies (60-90)
Direction determined by Coriolis effect
Strength determined by angular velocity
What is the Coriolis Effect and how does influence winds and circulation patterns?
It causes everything to shift clockwise in the Northern hemisphere and counter-clockwise in the Southern
- Do we see circulation of ocean currents? If so, why do they circulate and in what direction? What are the major currents of the Northern and Southern Hemispheres?
Yes, they circulate clockwise in the Northern hemisphere and counter-clockwise in the Southern because of the Coriolis effect
Northern- north equatorial current, gulf stream
Southern- south equatorial current, Peru current
- What is an ENSO event? What happens to regional and global climate during an ENSO event?
ENSO (El Nino Oscillation Event) reversal of equatorial current (going now from Aus to South America), signaled by deepening of warm water off coast of Peru.
What are climatic conditions like during El Nino and La Nina events? When are hurricanes most common in the Atlantic Ocean?
Fewer Atlantic hurricanes. Wetter in America, dryer in Australia during El Nino (ENSO)
La Nina, extreme reversal of El Nino, extreme weather in much of the world, increase in Atlantic hurricanes
What controls regional climates? What are topographical effects?
Ocean currents, atmospheric movement, continental location, nearness to large bodies of water, topographic features
Topography can created rain shadows and rain-ward sides of mountain ranges
What are the wet and dry adiabatic rates? Could these be used to determine the change in temperature with rise in elevation? What is Hopkin’s law?
Wet- 0.6 C / 100 m
Dry- 1C / 100 m
Yes in part
Phenological dates are retarded 1 day for each 100 m raise in altitude and 1 day for each 15’ latitude change
- Compare and contrast the windward vs. the leeward side of mountains.
the windward side of the mountian will have much more loisture than the leeward side
- What is an inversion? How are inversions formed? What are the common types of inversions?
An inversion is where the typical temperature gradient of air is reversed (cool air is trapped beneath hot air)
It forms in valleys where cool air slides down from the mountains under the hot air in the valley
Coastal inversion, canyon winds, subsidence inversion
- What is a maritime climate? What are the maritime effects on regional climate?
Maritime climate- climate near the coast
Maritime climates have much less variation in temperature due to the buffering effects of water
- What are cold and warm fronts? Why are there tornados in the Midwestern US?
Warm fronts are warm air moving in, they slide overtop cold air (stringy clouds)
Cold fronts are cold air moving in, they move below the warm air (thunder heads)
Tornadoes form when cool, descending air mixes with warm, ascending air. It happens in the Midwest because there are no mountain ranges to break up these patterns
- What is a microclimate? What effects do aspect, soil characteristics, and type of vegetation have on microclimates?
Microclimate- the climate conditions within an organisms habitat
Aspect- south facing slopes have more sun and less moisture and trees
Soil- the available nutrients
vegetation- Vegetation prevents the soil from heating up and deflects wind
- What are the ecological differences associated with slope aspect (i.e. north and south-facing slopes)?
South facing slopes have more sunlight, less moisture, less trees (in the Northern hemisphere)
- What are the characteristics of an urban climate?
They create hot spots, inverstion, winter fog, more cloud cover, more calms, less sunshine
- What has been the pattern of historical climate change? What are the long-term astronomical cycles that help give rise to the observed, cyclical pattern of climate change?
Fluxuation between glacial and interglacial periods, on a 100,000 year cycle. Quick heatings and slow coolings.
- Variable tilt of the earth (41,000)
- Variable eccentricity of earth’s orbit (100,000)
- Precession of equinoxes (21,000)
- How have humans modified climate? How do organisms respond to climate change? Will organisms adapt to future climate change?
We have introduced more greenhouse gases into the atmosphere
Organisms respond independently of each other (varying ranges)
Doubtful, because we have decreased their populations
- What is soil? What are the physical properties of soil? What is the available water capacity of soil?
Soil is complex, loose terrestrial surface material
Color, texture, depth, moisture
The difference between the field capacity and wilting point
What is the cation exchange capacity of soil?
Negatively charged clay and humus retain cations due to isomorphos substitutions (ex. Al3+ substituted for Si4+)
- What are the soil horizons? What determines soil structure? What are the types of weathering?
Horizons- the different layers in the soil
O- surface layer of fresh organic material
A- accumulation of organic material, loss of some clay and soluble matter
E- zone of maximum leaching- formation of granular, platelike, or crumblike structures
B- zone of illuviation, collection of leached material.
C- weathered material
R- unweathered bedrock
Structure determined by climate (precip), parent material, age of soil, topogrophy, vegetation
What are the soil development processes?
- Mechanical - glaciers, freeze/thaw cycles, waterways
2. Chemical- oxidation / reduction, dissolution, hydrolysis, carbonation
How are soils classified? Describe the following soil orders: aridisol, pedocal, mollisol, pedalfer (alfisol), spodosol, and oxisol. Where would you find these soil orders?
Classified based on their soil horizons
Aridisol- soils in arid areas, A horizon only, Great Basin
Pedocal- soils with calcium carbonate (caliche or hardpan) layer in B layer, also Great Basin
Molisols- good, rich soil, prairie ecosystems, big A and O layers
Pedalfer (alfisol)- Soil high in Al and Fe oxides found in B layer, deciduous forests caused by podsolization.
Spodosol- shallow leached horizon and deeper layer of deposition.
Oxisol- found in tropical rain forests, nutrient poor, huge E (leeching) horizon, sandy, red
- Describe podsolization and laterization.
Podsolization- small clay particles break down and are leeched into E layer where they cannot be used by plants
Lateralization- produces red soil, lots of water makes the soil leech rapidly and soil tends to be acidic, found in rain forests
- What is the biome concept? What are ecological tolerances? How did Whittaker define biomes? What environmental factors are used in Whittaker biomes?
Nature of plant and animal life is determined by climate, topography, and soil. Because of convergence, similar dominant plant forms occur under similar conditions
Defined by temperature and precipitation
- What are aquatic biomes? How are they categorized?
Underwater biomes
Categorized by flow, depth and salinity
- Describe circulation ponds and lakes. What is stratification?
Deep and shallow waters mix in spring and fall by wind, waters stratify in Summer and Winter
The layering of different temperatures
Define the following terms: epilimnion, hypolimnion, thermocline, limnetic zone, benthic zone, profundal zone, photic zone and aphotic zone.
epilimnion- surface layer of water with distinct temperature
hypolimnion- deeper layer of water with distinct temp
thermocline- middle water that experiences rapid temperature change
limnetic zone- photosynthetically active zone away from the shore
benthic zone- sediment at the bottom of the lake
profundal zone- water column without sunlight in lakes
photic zone- zone in open ocean where sunlight is plentiful
aphotic zone- zone in ocean where no light is present
