C4.2 Transfer of energy and matter

C4.2.1 Ecosystems (open+closed syst)

Ecosystem: all of organism + abiotic factors in area

Open system: both matter and energy can enter/exit (also in ecosyst)
Closed system: energy can enter/exit, matter can’t

C4.2.2 Sunlight

Primary energy source for most ecosystems: producers convert solar→chemical E

C4.2.3 Food chains

Producer (show feeding relationships): primary consumer → 2nd → 3rd …

Arrows symbolize flow of energy

C4.2.4 Food webs

Food webs more realistic: show all possible food possibilities in community.
Can be classified per trophic level

C4.2.5 Decomposers

Energy supplied to them as carbon compounds in organic matter from dead organisms

recycle nutrients - VERY necessary

saphrotroph: digest externally: fungi, detrivores:digest internally

C4.2.6 Autotrophs

Producers. make organic out of inorganic: make carbs, a.a., fatty acids, steroids…

Plants, algae, cyanobacteria

C4.2.7 Energy sources

Photoautotrophs use light to build molecules

Chemoautotrophs: oxidation reactions: oxidize Iron for own energy

C4.2.8 Heterotrophs

Receive carbon compounds by feeding on other organisms.
Digestion: chemical breakdown of molecules into different molecules

Can be digested & absorbed internally/external

C4.2.9 Oxidation of carbon compounds in respiration

All organisms need ATP: use cell resp to get it. oxidize carbon compounds to do so.
Auto: use own, Hetero: use consumed

C4.2.10 Trophic levels

where organism is in food chain

primary producer → primary consumer → secondary consumer (dependent on path)

C4.2.11 Energy pyramid

pyramid shows amount of energy gained per area per year (kJm^-2yr^-1)

10% rule: stepped pyramid!!!

Label with trophic levels

C4.2.12 Reduction in energy per succesive stage

90% of energy is lost in each trophic level → limit height of food chain
cell respiration, incomplete consumption, incomplete digestion + heat loss

C4.2.13 Heat loss

In both auto/heterotrophs bc of conversion chemical → heat in cell respiration.

Helps warm blooded, but not useful in trophic levels.

To sustain ecosystem: need constant energy flow

C4.2.14 Restrictions on nr of trophic levels

maximum 4

biomass is limited: with energy pyramid, similar in #

C4.2.15 Biomass

Need lots of autotrophs, less 1-consumer, even less 2-consumer etc…

Increase biomass of primary producer → increase rest as more food.

C4.2.15 Primary production of carbon compounds

GDP: gross primary production: total biomass made (GPP>NPP)
NPP: net primary production: available to consumers bc of loss of biomass (resp)

gCm^-2yr^-1 (grams of carbon per area per year)

Different biomes = diff production capacities

C4.2.16 Secondary production

Heterotrophs biomass: less and less as you go up trophic levels: need less plants if you eat vegetarian as less energy is lots if you are a secondary vs a primary consumer so need less…

C4.2.17 Carbon cycle

Pool: reserve (box), Flux: transfer of 1 pool to another (arrow)
Atmosphere → (photosynthesis) producers → (eaten)consumers → (respi) atmosphere
consumers/producers → (death) dead matter →^(resp)atmos/_{(fossilization)fossfuel →(comb)atmo}

Labelled stuff…

C4.2.18 Carbon sinks and sources

Fluxes of carbon = photosyntesis + respiration (+ decomposition & now combustion)

Sink; take up C: lot of photosynthesis, less respiration
Source: release C: less photosynt, more respiration

C4.2.19 Fossil fuel combustion

Fossilization: carbon sink: peat, coal, oil, natural gas…: burn = release carbon

Need equilibrium w uptake/releasing: right now, not, so atmospheric C is increasing

C4.2.20 Keeling curve

Show CO₂ levels over time

Annually up-down: up in autumn/wint, down in spring/sum: photosynthesis rates
Overall up: anthropogenic activity

C4.2.21 Aerobic respiration and photosynthesis

Depend on each other. Product of 1 is substrate of the other, vice versa

Lots used/produced 10¹⁵ grams (1 gigaton) per anything…

C4.2.22 Recycling chemical elements

C, H, O, N, P, (others)
All of those have cycles; quantities limited so need to be recycles/returned for reuptake