A Speed Gun for Photosynthesis | Hacker News Reader

A Speed Gun for Photosynthesis

nist.gov

76 pointslainon15 comments

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.

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

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.

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.

I wonder if this sort of technology could become a standard for evaluating towns and quality of life. For instance, a drone or fixed cameras mounted throughout a town could provide an aerial view of how "green" that town is, both in terms of literal greenery and how much CO2 is being absorbed.

My personal belief is that towns/suburban life is dying by the very thing that made it: cars. Not only is pollution a huge problem, but at least with the towns that I've lived in, greenery is being torn down entirely and being replaced with a sea of cement, asphalt, shopping plazas, highways, etc. I'd love to use a tool like mentioned in the article to actually quantify and grade/score a town on this matter. Then codify in law certain "greenery standards".

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.

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"

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.

We already do remote sensing in these wavebands and chlorophyll fluorescence spectroscopy has been around a long time. The amount of signal due to chlorophyll fluorescence is very very small. I think if your going to spend the bucks on an advanced sensor to do this kind of work, you just go whole hog and do hyperspectral imaging.

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

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

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.

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.

that looks pretty cool

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.

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

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