lecture 6 Primary Production

where does energy come from? how much is absorbed & how much reflected? what happens to light absorbed into water? what is adding to increased heat energy?

All energy from sun -some gets to surface -50% absorbed into surface or atmosphere -20% absorbed in water and then evaporates into atmosphere at heat energy 30% of light is reflected 70% of light is turned into heat energy adding to heat energy by burning fossil fuels

comparisons of C3, C4, and CAM plants. what type of plants are in each category? which is most energy efficient? which is best at water conservation?

C3 = most plants C4 = grasses (corn/sugarcane) CAM = succulents, pineapple, agave C3 most energy efficient C4 half way between the two CAM is best at water conservation C3 loses water through photorespiration C4 loses less water than C3 CAM lose the least water

advantage of C4 plant? does C3 or C4 produce more overall carbon?

C4 can take in CO2 at extremely low concentrations (normal is 400 ppm in air) C3 down to 50 ppm & still get synthesis C4 down to <0.1 ppm (500X lower concentration) & will produce sugar --> can produce more overall carbon due to this

(C3/C4) more tolerant to hot, dry, and special water stressed conditions. why (2)?

C4 more tolerant Stomata are fewer per cm2 of leaf area -Less across leaf surface C4 plants open stomata less often to take in CO2

C3 vs C4 leaf structure. how are C4 plants grouped?

C4 plants --> cells containing chloroplasts are grouped around vascular bundles in bundle sheath. This separation from the epidermis is the only way the 4 carbon acids can perform their function -Store C4 compounds in bundle sheath where photosynthesis occurs (more efficient) C3 = grouped randomly

what do dinoflagellates do in response to sunlight? are they autotrophs or heterotrophs? give an example of a dinoflagellates

Can migrate vertically (up/down water column) in response to sunlight Can be autotrophs and heterotrophs (need to eat) example = Zooxanthellae, symbionts in coral reefs --> part of coral that photosynthesizes = zooxanthellae = dinoflagellates!! many odd shapes

Carbon turned into organic matter; reserves for . . . (3)

Carbon rich soil Peat deposits Fossil fuel deposits

what is the endosymbiotic theory?

Chloroplasts were bacterial cells Engulfed by larger eukaryotic cells! we know this because chloroplasts have their own DNA lots of evidence for this -also proposed for evolution of mitochondria

examples of phytoplankton (4)?

Coccolithophores Diatoms Dinoflagellates prochlorophytes plankton = drift; phyto = uses photosynthesis

why can mangroves live in water?

Complex roots so can live in water --> no air so must deal with submergence

what are lichens?

Composite symbiotic organism consisting of a fungus and an alga (usually green)

which phytoplankton are mobile?

Dinoflagellates usually have two flagella to make them motile still being moved by currents mostly but this helps with slight movement (not like fish movement)

what do coccolithophores have that are distinctive? what does this allow? what do coccolithophores form? will they respond well to increasing CO2?

Distinctive calcite plates -Makes them heavy -Large component of carbon export to deep ocean --> will take carbon and sink to bottom of ocean Forms limestone over long time period May respond well to increasing CO2

are estuaries, algae beds, and reefs good at primary production? do they contribute a lot to the total productivity percentage?

Estuaries, algae beds, reefs good at primary production but less than 1% of earth surface so do not contribute much to total percentage this is why its important to save these areas - contributes to primary production!

what do mangroves export to adjacent waters? how do they obtain this material? what are mangroves an important buffer for?

Export organic matter to adjacent waters Fix carbon from atmosphere into biomass and then exported into coastal waters (900g carbon per year) Important buffer between ocean and land! (storms)

lichens are a composite symbiotic organism made of a fungus and an alga. what does the fungus do (3)? what does the alga do?

Fungus provides substrate, source of water, and nutrient base Alga synthesizes food carbons through photosynthesis

Global Primary Productivity: where is it the highest? moderate? the lowest?

Highest = eastern boundary coastal regions (upwelling areas) -Green areas -Deep water being brought up so nutrients brought up Next highest = coastal regions -Nutrients from land run off Moderate = open ocean Lowest = subtropical gyres -Pink on graph -Very low primary productivity -Large part of the ocean

what characteristics do macro-algae have (3)? what do each do?

Holdfast (anchor) --> nonvascular! are not roots Stipe (stem-like) blade (leaf like) --> used for light collection

what are prochlorophytes? what do they fix? why is this important? where do they dominantly live? why are they globally important?

Marine cyanobacteria (Phytoplankton) Many fix N2 (nitrogen) from atmosphere into biomass --> fertilizes system so nitrogen can enter food web Dominate in oligotrophic waters (low nutrients aka areas of low productivity) Important globally: ~20% of O2 in atmosphere from these bacteria!

is there cellulose in algae carbon containment structures?

NO

can diatoms be successful out of water? why or why not?

NO due to silica shell

Productivity: Ocean vs Land. what are open oceans similar to? what are upwellings & near-shore zones (marshes/estuaries) similar to?

Open oceans are similar to deserts on land in terms of total primary productivity Upwelling & near-shore zones (marshes, estuaries) are similar to agricultural fields on land --> high productivity Ocean productivity is ~ 50% of global productivity -Terrestrial is other 50% Salt marches have really high productivity --> these are regions at risk

how do C4 plants handle low moisture environments?

Open stomates during day but not as frequently as C3 plants -Store some carbon in C4 form -Specialized metabolism to deal with loss of water during hot, dry day

define autotroph. what do they form?

Organisms capable of synthesizing their food from inorganic compounds form the basis of all food webs

Rates of production comparison: tropical rainforest vs deciduous forest. which has seasonal production? which has a larger surface?

Rates of production comparison from tropical rainforest to temperate deciduous forest -tropical rainforest has greater average net primary production -Deciduous forest not too bad in comparison (seasonal) --> More primary production in summer Percentage of surface -Tropics are large part of surface so contribute a lot of net primary production

all grasses are (C3/C4). all desert plants are (C3/C4). can one genera have both types of plants?

Virtually all grasses are C4 Most desert plants are C4 Some genera have both types, i.e. saltbush - Atriplex patula is C3 - Atriplex rosea is C4

what does the xylem do? the phloem?

Xylem moving water up system --> has cell walls which had rigid cellulose compounds to store carbon Phloem moves carbon (energy sugars) to sinks throughout plant aka where it is needed (Apical meristem, leaf surfaces)

can UV damage cell organelles? what occurred due to this?

YES Lots of UV light from sunlight -Problem on terrestrial surface Plants adapted structures/compounds to deal with solar radiation --> flavonoids, phenolic compounds, photolyase

how does a savannah compare with areas of dry/wet seasons?

about the same net production

which factor has the greatest influence on limiting diversity (limiting factor) and is the best predictor of species richness in terrestrial plants and animals?

ambient energy! temperature, water, sunlight

what are flavonoids? how do they help with radiation? what does radiation stimulate in these cells?

associated with plant pigments can protect against excess UV radiation (100-400 nm wavelength) --> UV light cannot get through leaf surface bc of these compounds but visible light can still pass through to get to chloroplast and be used UV also stimulates enzymes to make more of these compounds to protect from UV light

chloroplasts are the basis for what? what do these allow? how many chloroplasts in each leaf mesophyll cell? in each leaf?

basis for nearly all the photoautotrophs --> photosynthesis provides nourishment (C) for nearly all of the living world 30-40 per mesophyll cell --> thousands of chloroplasts in a plant leaf

what are harmful algal blooms termed? why are these harmful? which type of phytoplankton produced red tides?

called "red-tides" due to pigmentation of algae can produce harmful toxins that impact human health (can cause death, amnesia, paralysis) Most red tides are produced by dinoflagellates

what are carbon fluxes? give examples

carbon flux = carbon going into different forms -Soil respiration, burning fossil fuels, plant respiration photosynthesis then capturing that carbon and putting back into plant to produce sugars carbon moving back and forth between storage areas

where is carbon mostly stored (2)?

cellulose & woody fibers

what is the major component of wood? what does this store?

cellulose (plant cell wall structure) good for storing carbon!

what do phenolic compounds do?

compounds in epidermis absorbs UVB and protect plant cells

how have plants adapted to protect themselves against herbivores ranging from microorganisms to large vertebrates? give 5 examples

compounds that give plants a bad taste Flavonoids Tannins Terpenoids Alkaloids Glycosides Many algae also have secondary compounds!!

what does CAM stand for? what do these plants do to deal with low moisture environment? what do they create from CO2? what is CO2 stores as? what is limited by the way these plants act?

crassulacean acid metabolism stomata stay closed during the day and open at night -Prevents water loss during day -Allows CO2 entrance at night Create C4 carbon compound that they store into malic acid/malate and then during day with light, take C4 compound and break it down into C3 and then into calvin cycle etc In between C3 and C4 plants Limits water loss but also limits CO2 that diffuses into the leaf for photosynthesis

Importance of estuaries?

diversity is driven by productivity high productivity in these areas so high diversity!

why did C4 and CAM plants evolve?

evolved adaptations for alternative ways to fix carbon in hot, arid (low moisture) climates converts CO2 to a 4 carbon sugar

what is the primary production in carbon sinks?

fixing carbon into other things like sugars

how can carbon capture be increased?

grow more trees/forests to increase storage areas and reduce carbon in atmosphere

what are true plants (3 characteristics)? give examples (4) x

have true roots, stems and leaves flowering plants, seagrasses, marsh grasses, mangroves

is chlorophyll's DNA dependent or independent from the cell?

independent member of a cell with its own DNA

how much sun energy do foliage aka living organisms get?

less then 1%!

what do woody plants have that give structure and is a carbon polymer?

lignen Gives woody plants carbon storage and rigidity

where can diatoms live (fresh or salt)? what is their shell made of? what do they require? what do they look like? what is their dominant pigment?

live in fresh water AND salt water shell = SiO2 (frustule) -require silica in order to make the shell! single celled or chains, typically symmetrical (chains allows them to be bigger and get eaten less) dominant pigment = Fucoxanthin, a yellow-brown pigment that masks chlorophyll

are there high amounts of carbon stores in the forest? in grasslands? x

lots of carbon stored in forests (long standing trees) grasslands store some carbon but not as much as woody plants

what does CAM plants convert the 4 carbon sugar into in order to store it overnight and then use it during the day when light is available?

malic acid/malate during day with light, take C4 compound and break it down into C3 to enter calvin cycle

are algae true plants? where are algae found?

no macro and micro algae very important for marine systems found at relatively shallow depths

how are algae classified

on pigments and storage compounds

World Ocean Primary Productivity: give areas of highest productivity from most to least per unit area AND per total productivity

per unit area: upwelling --> coasts --> open ocean per total productivity: open ocean --> coasts --> upwelling open ocean has a lot more area so global productivity increased more by open oceans than upwellings (high productivity but very low area so do not contribute a lot globally) open oceans have considerably less primary productivity than upwellings -But upwellings are 0.1% of total ocean

photosynthesis (increases/decreases) with depth. what is the compensation depth? how does production change below/above the compensation depth? what is the oxygen minimum zone?

photosynthesis drops with depth due to lack of light Depth where rate of photosynthesis = rate of respiration --> compensation depth (net 0 production!!) Below compensation depth, brown sticks out further --> more respiration than photosynthesis -Net negative here Positive net production above compensation depth Oxygen minimum zone at bottom -Way less photosynthesis so less oxygen

what does photolyase do? how is it activated?

repairs damaged DNA pairs UV-A & blue activates photolyase

what is another name for macro algae? what can they proliferate to become?

seaweeds Can proliferate to become "nuisance" algae (big mats of algae)

are true plants restricted to shallow or deep areas? why (2)?

shallow areas bc need to put roots in ground somewhere and also get sunlight

Most of the Carbon on earth is where? is this accessible?

the mantle and the sediments unaccessible

what do C3 plants do?

use normal photosynthesis converting CO2 to 3-carbon phosphoglycerate that enters calvin cycle

is macro algae aka seaweed productive? do they contribute a lot or not much globally?

very productive but not globally up to 2000g per year but covers a proportionally small area of earth so does not provide a lot globally

what are oligotrophic waters?

waters with low nutrients aka low productivity prochlorophytes do well here

can photosynthesis occur in hydrothermal vents? what are they reliant on?

Too deep for photosynthesis (no sunlight) reliant on chemosynthesis --> bacteria use energy in chemical bonds of hydrogen sulfide to convert CO2 to sugar Many species have symbioses with bacteria to gain the sugar produced

Marine environment gets ___% of energy from sun

1-2

chemosynthesis equation. what is used at the energy source? how does it give energy and what does it do? what are the products?

6CO2 + 12H2O + 2H2S --> C6H12O6 + 3H2SO4 energy source = hydrogen sulfide! --> uses chemical bonds for energy (provides reducing power to reduce carbon dioxide over to fixed sugar) other chemicals can also be used that offer the same reducing power input = CO2, water, hydrogen sulfide (energy) product = sugar, sulfuric acid

photosynthesis formula. what are the products?

6CO2 + 12H2O + photons (light) --> CH2O + 6O2 + 6H20 input = CO2, water, energy produces sugar, oxygen, water

how much of the sun's energy escapes as heat energy?

70%

marine

Photo- and chemo- synthesis Hydrothermal vents Trends in primary production Marine Photosynthesizers Symbioses - Corals - Ingested chloroplasts Evolution of chloroplasts

terrestrial

Primary energy source Productivity in various communities Terrestrial photosynthesizers C3 and C4 plants Chloroplast in relation to symbiosis

what are seagrasses? what occurs when water becomes cloudy? why is this problematic?

Rooted, flowering plants (angiosperm) very sensitive to light availability --> when water is cloudy, phytoplankton will be lost (very problematic bc these are nurseries for juvenile fish and shellfish) take 4000g carbon out of atmosphere and fix it

how did plants adapt in high level UVR environments aka tropical/high altitude (6)? give an example of a plant

Shorter with denser branching Leaves smaller but thicker with different epidermal and cuticular structures Waxy leaves, leaf hairs and leaf bladders evolved to have high levels of phenolic compounds already in plant structures so do not need to spend energy activating enzymes Ex. succulents

Coral has a symbiosis with what other organism? how much algal production goes to coral? what does the algae get (3)? what does the coral get (3)?

Symbiont is a dinoflagellate = zooxanthellae Coral gets organic matter from photosynthate 90% of algal production goes to coral -Algae gets protection, CO2, nutrients coral gains = Algae draws down CO2-, raises pH, prevents dissolution of CaCO3

Plant growth patterns protects against excess UV (T/F)

TRUE!

Primary Productivity in Various Communities (marine vs terrestrial). which has a higher percentage of the earth's surface? do terrestrial or marine species contribute more to productivity?

Terrestrial enviro = 29% of earth's surface but is almost equal to marine in average net primary production Total percentage net primary production --> terrestrial contributes to a greater extent