
A Speed Gun for Photosynthesis - lainon
https://www.nist.gov/featured-stories/speed-gun-photosynthesis
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jefflab
For those interested in this topic, you also might be interested in sensors
that can measure evapotranspiration (ET). ET is directly related to
photosynthesis and crop yield.

Here is a quick refresher from the textbook on plant water relations:

> Stomata are microscopic valves present in all leaves, formed by the pairing
> of specialized cells called guard cells on the leaf surface. Stomata are the
> main ports through which water vapor is lost. Of equal importance is the
> fact that stomata also are the main ports through which carbon dioxide gas
> moves from the air into the leaf and is photosynthesized into plant material
> and accounts for most of the plant dry matter produced. - Hsiao

Our company, Tule Technologies (YC S14) is the commercial vendor of sensors
that can measure evapotranspiration. We solve many of the problems mentioned
in this article.

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bullfightonmars
Interesting. Do you measure ET as the a residual energy balance of
radiative/sensible heat flux?

[http://www.plantphysiol.org/content/143/1/134#sec-11](http://www.plantphysiol.org/content/143/1/134#sec-11)

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jefflab
Yes, we measure ET through an energy balance approach. It is called surface
renewal.

Thanks for the link. I'll add it to my queue to read.

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sova
As a nature loving human and a person who is absolutely fascinated by plants,
chlorophyll, photosynthesis, and the stunning and elusive world right before
us, I'm really happy our technology is trending towards plants and
understanding them.

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agumonkey
plot twist: in 200 years, the most advanced humans will just be nomads in
nature. The difference is that with proper understanding in and out (as
opposed to "out" folk knowledge) they don't feel the need to rush for tech and
"modern comfort"

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BatFastard
This will revolutionize greenhouses and aquaculture. Now you can optimize
everything based on plant growth rate. Just need a few million data points and
we can sic the AI on it.

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tw1010
I don't think you're wrong, but I suspect the reason you're being downvoted is
because of the cliche AI-enthusiastic rhetoric.

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BatFastard
But it's a great application for AI, or would they prefer ML or DL? Its a
dataset with near real time response.

As for downvotes, I try to add to the discussion, if people don't like it, oh
well, it's only numbers. (unless there is a secret ritual for people who go
over 100,000??)

[ed] Speeling correction

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RosanaAnaDana
Well, we do use ML quite a bit in scene classification, but as I said earlier,
there is really nothing revolutionary about what was being presented in that
article. Its all old science and methods that have been in employ for decades.
LiDAR and hyperspec is the way to go, but as is ALWAYS the case, its all hand-
waving without good reference data.

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Joann121
We know that seeing nature reduces stress, cleans the air, etc., so this truly
is a matter of quality of life as much as it is about our environment. If more
people cared about the earth we would all be in better health.

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lostfile
that looks pretty cool

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RosanaAnaDana
Does it bother any one else that she is pointing the instrument at a glass
window, which is opaque to NIR? I mean I get it, they come in for a photo-op
and they want to see the instrument, but at least open the window.

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npk
It turns out that this wavelength of infrared is short enough that it sees
through windows just fine.

