Which finding from the researchers' study, if true, would most direct…

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Permafrost in Alaska has been degrading, potentially enabling increased carbon dioxide (

C O_{2}

) absorption through greater productivity of bristle-pointed iris (Iris setosa) plants and other vegetation, but also potentially enabling increased

C O_{2}

output through greater heterotrophic respiration (

C O_{2}

generated by the activity of soil microorganisms). Hydrologist Yonghong Yi and her colleagues modeled seasonal changes in net

C O_{2}

in Alaska in a landscape grid of

1 km^{2}

cells and again in a grid of

10 km^{2}

cells, which are finer resolutions than most models of net

C O_{2}

have achieved. The researchers concluded that variations in the landscape affect net

C O_{2}

in ways that most models are too coarse to capture.

Which finding from the researchers' study, if true, would most directly support the researchers' conclusion?

Lower average heterotrophic respiration rates were found for autumn months when modeled using a grid of

1 km^{2}

cells than when modeled using a grid of

10 km^{2}

cells.

When seasonal fluxes in average

C O_{2}

absorption and heterotrophic respiration were modeled using a grid of

1 km^{2}

cells, much more data were generated than when seasonal fluxes were modeled using a grid of

10 km^{2}

cells, though the two models reported identical net

C O_{2}

Higher average heterotrophic respiration rates were found for summer months than for winter months when modeled using either a grid of

1 km^{2}

cells or a grid of

10 km^{2}

cells.

No correlations between seasonal variations in average heterotrophic respiration and

C O_{2}

absorption by I. setosa and other plant species were found when modeled using either a grid of

1 km^{2}

cells or a grid of

10 km^{2}

cells.