Which of the following statements best describes "carbon fertilization" ?

Explains that carbon (as CO2) moves from the atmosphere into green plants via photosynthesis, linking atmospheric CO2 to plant carbon uptake.

A student could infer that higher atmospheric CO2 might increase the raw substrate for photosynthesis and so could plausibly boost plant growth under some conditions.

States that CO2 is vital for production of carbohydrates through photosynthesis, emphasizing CO2 as a limiting input for plant organic matter production.

Combine this with knowledge that photosynthesis rates can respond to CO2 concentration to judge whether extra CO2 could increase plant biomass.

Describes how plants obtain CO2 through stomata for photosynthesis, showing the physiological pathway by which atmospheric CO2 reaches plant photosynthetic machinery.

A student could reason that if stomatal gas exchange supplies CO2 to leaves, higher atmospheric CO2 increases the gradient for uptake and may raise photosynthetic CO2 assimilation.

Notes that atmospheric CO2 has increased substantially over the last century, providing the environmental change that would be necessary for any 'carbon fertilization' effect to occur.

Use this trend plus known plant responses to higher CO2 to assess whether observed CO2 increases could drive detectable growth changes.

Mentions 'fertilization' in the context of ocean carbon sequestration (ocean fertilization), showing that the term 'fertilization' is used in carbon-management contexts to mean adding carbon or nutrients to stimulate biological uptake.

A student could extrapolate that 'carbon fertilization' might analogously denote stimulating biological (plant) growth by increasing available carbon (CO2) in the atmosphere.

Mentions 'ocean sequestration' via 'direct injection or fertilization', showing 'fertilization' is used as a carbon storage/mitigation technique, not as a description of warming.

A student could infer that 'fertilization' in this context is an active intervention to increase carbon uptake (e.g., adding nutrients to oceans) rather than a synonym for temperature rise.

Explains that higher atmospheric CO2 amplifies the greenhouse effect and causes Earth's surface temperature to increase, establishing the definition of CO2-driven warming.

Combine this with evidence that 'fertilization' is a sequestration tactic to argue that 'carbon fertilization' likely does not mean temperature increase but is a different concept.

States CO2 is responsible for the greenhouse effect and rising temperatures, reinforcing that 'global warming' is the accepted term for CO2-caused temperature rise.

Use this rule (CO2 → greenhouse effect → warming) to contrast terminology: if 'fertilization' appears in sequestration contexts (snippet 8), it likely refers to biological/chemical enhancement, not warming.

Describes CO2 as an 'efficient absorber of heat' that raises atmospheric temperature, again defining warming as CO2's climatic effect.

A student could use this to separate 'warming' (a radiative effect) from interventions labeled 'fertilization' (which aim to store CO2), supporting that the latter is not the temperature effect itself.

Explains that CO2 forms a cover that traps solar heat and increases Earth's temperature, giving a clear label for the warming phenomenon (global warming) associated with CO2.

A student can contrast the explicit label 'global warming' for CO2-driven temperature rise with the use of 'fertilization' in sequestration contexts to infer differing meanings.

Defines 'fertilization' as a method of ocean sequestration (carbon stored in oceans through direct injection or fertilization), showing 'fertilization' is treated as an active carbon‑storage technique rather than the chemical acidification process.

A student could use this to infer that 'carbon fertilization' is likely an intervention to increase biological uptake/store carbon, so check whether such interventions are distinct from the chemical reactions that cause acidification.

Explains phytoplankton consume CO2 during photosynthesis and transfer carbon into organisms, linking biological uptake (fertilization can stimulate this) to carbon removal from the atmosphere.

Use the biological uptake idea to distinguish terms: if fertilization boosts photosynthesis it reduces CO2 locally, which is different in mechanism from CO2 forming carbonic acid and increasing H+.

Gives a clear definition of ocean acidification as the chemical change (lowering of pH, rising H+ and lowered carbonate) driven by uptake of atmospheric CO2.

A student can contrast this chemical reaction definition with the biological/engineering notion of 'fertilization' to judge whether the two terms align or refer to different processes.

Describes the specific chemical reactions when CO2 reacts with seawater to form carbonic acid and release hydrogen ions – the mechanistic basis of acidification.

Combine this reaction detail with the idea of biological carbon uptake (snippet 7) to reason that 'fertilization' (stimulating biology) and 'acidification' (chemical proton increase) are distinct mechanisms.

Defines 'carbonation' as CO2 forming carbonic acid and carbonates in terrestrial weathering, showing a broader usage where CO2 + water → carbonic acid is a named chemical process.

Use this terrestrial example to generalize that CO2 producing carbonic acid is a chemical definition (acidification), separate from 'fertilization' which implies nutrient-driven biological responses.

Explains that atmospheric carbon dioxide moves into green plants via photosynthesis, i.e., CO2 uptake stimulates plant growth as part of the carbon cycle.

A student could infer that 'carbon fertilization' likely refers to CO2-driven increases in plant growth rather than a broad adaptation of all organisms, and check specialized sources on the term.

States trees, plants, and tiny ocean plankton absorb CO2 as they grow, highlighting organisms that directly respond growth-wise to higher CO2.

Extend by noting these examples (plants, plankton) are typical subjects of 'fertilization' and so the term probably targets growth responses in photosynthetic organisms.

Mentions 'ocean sequestration' through direct injection or fertilization, using 'fertilization' in the context of stimulating biological uptake in oceans for carbon storage.

Use this usage-pattern to suspect 'carbon fertilization' refers to enhancing biological uptake (e.g., algal blooms) rather than to a general adaptation of all life.

Describes how increased atmospheric CO2 traps heat causing climate change and notes disruption of ecosystems that plants, animals, and humans adapted to, separating CO2 effects into warming vs. biological uptake.

A student could use this to distinguish between (a) CO2 causing climate change (affecting adaptation) and (b) CO2 acting as a resource that may boost plant growth (fertilization).

States that rising greenhouse gases (CO2) amplify the greenhouse effect and raise temperatures, emphasizing the climate-change role of CO2 apart from any fertilization effect.

Combine with snippets about photosynthetic uptake to test whether 'carbon fertilization' denotes growth stimulation rather than global biological adaptation to warming.