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EDmodel / ED2

Ecosystem Demography Model
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question about unit in reproduction.f90 #351

Closed Lo-hatch closed 2 years ago

Lo-hatch commented 2 years ago

the calculation of nplant of new recruitment cohort is as: rectest%nplant = csite%repro(ipft,ipa) / biomass In my opinion, the units of "repro" and "biomass" are "kgC m-2 polygon yr-1" and "kgC plant-1", so the unit of "nplant" is "plant m-2 polygon". However, the unit of "NPLANT" in ED should always be "plant m-2 patch" ? Is that a mistake or I misunderstand the units of these variables?

The link is the relevant code block: https://github.com/EDmodel/ED2/blob/master/ED/src/dynamics/reproduction.f90#:~:text=rectest%25nplant,rectest%25bstorage)

mdietze commented 2 years ago

As you note, csite%repro(ipft,ipa) is indexed by PFT and patch. Thus it has units "kgC m-2 patch yr-1" not "kgC m-2 polygon yr-1"

mpaiao commented 2 years ago

Just for future reference, if a patch-level variable (csite%variable(...,ipa)) has m-2 in its units, then you can always assume that it is "m-2(patch)".

The only exception is csite%area(ipa), which has units of m2(patch) m-2(site). Likewise, cpoly%area(isi) has units of m2(site) m-2(polygon).

Lo-hatch commented 2 years ago

@mdietze @mpaiao Thank you very much! I misunderstood the unit of repro.