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PNNL-PREMIS / bc-incubation2018

Aditi's 2018 Beaver Creek incubation
MIT License
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Where is core dry weight data? #9

Closed bpbond closed 4 years ago

bpbond commented 4 years ago

Need to normalize fluxes by dry weight (I assume).

bpbond commented 4 years ago

I see the wet_weights.csv file, but nothing for dry end-of-experiment weights.

AditiGit commented 4 years ago

Yes. I only have dry weights for the end of the experiment when the cores were harvested. I planned to apply moisture content values to the wet_weights throughout the experiment. These won't be the exact numbers since the cores lost moisture, were wet-up to the field weight, lost moisture again, and so on. Wanted to ask you if this is standard procedure where end-of-experiment moisture content is applied as an average to the entire experiment. This does not sound right to me and I am open to suggestions about addressing this.

bpbond commented 4 years ago

Normally I think people normalize by dry mass regardless of anything else they do. Ignore the fluctuating wet weights for a moment; even if they were perfectly constant, we'd still have different amount of soil medium in each core, and want to know flux/g normally, where g is g dry mass, not just flux.

AditiGit commented 4 years ago

Okay, should be able to get this to you by end of work day. heading into the lab right now for some on and off lab work but will get this to you when i have down time in between.

AditiGit commented 4 years ago

Added dry weight values to "BeaverCreek_2018Incubation_PICARRO_Metadata.csv" file. I used the dry gravimetric moisture content from cores harvested at the end of the experiment. Since I sub-sampled for 2 heights, I used the average moisture content of two depths to represent moisture content of the core.

bpbond commented 4 years ago

I don't see a commit 😕 feel free to email if easier. Thanks!

AditiGit commented 4 years ago

yikes...updated the file on shared drive. I tried pushing the file but I don't seem to have permissions. Just emailing it to you to save time.

bpbond commented 4 years ago

Hi @AditiGit - looking at the file you sent and I'm quite confused. What I was expecting was a list giving one entry per core: its dry weight as measured at the end (typically) of the experiment.

Instead, there's one entry per measurement, with a dry weight that varies, sometimes by by a LOT. 😕 How can the dry weight vary? I guess you're computing it from gravimetric water content (though no formula is visible). Why? How is gravimetric wc computed? The crazy-varying dry weight values will wildly throw off normalized fluxes, which is why I'm concerned.

Anyway, can you explain the steps that produced these values please?

AditiGit commented 4 years ago

Fixed. we were on the same page. Calculated gravimetric moisture content from the the core initial core moist weight (logic being that we ideally maintained weights throughout the experiment). Used formula Dry weight = moist weight/(1+wd) where wd is dry gravimetric moisture content. Emailed the file to you.