We are looking for a field portable CH4 and CO2 analyzer for field custom chamber fluxes in peatlands at high elevation (~3000 up to ~4500 m), lower temperatures (as low as 5oC), with lots of rain in the Andes of Colombia. These two models (Picarro G4301 GasScouter and Los Gatos Research LGR-ICOS™ M-GGA-918 Microportable Greenhouse Gas Analyzer) are both field portable and manufacturers claim they will work at these elevations (LGR would need to add a larger pump). We would be using them with custom chambers to do NEE and ER measurements. Any experience with either or both of these under field conditions? I have heard that the pump on the GasScouter can produce small amounts of methane-- anyone seen sufficient flux for that to be a problem? Other strengths or weaknesses?
Hello Erik,
I’ve been working for 2+ years with the scouter and planning on doing so in LA. I’ve performed more than 400 chamber runs in different environments, including marshes, rivers, and forests. The scouter is both sturdy and versatile at the same time. I’ve operated if from canoes, boats, and the soil forest without major issues. High temperatures (+35C) may cause some operability issues (the internal cpu crashes because of the heat and the connectivity with the tablet got lost). I know up there in the paramo things may heat up quickly on a sunny day, so try to keep it in the shade. When it happened, it was just a matter of unplugged from the battery and restart the instrument.
Portability is indeed, a factor to consider. The Scouter is a backpack, whereas Los Gatos is like a business case. Wading through the peat bog cushions, while trying not to sink is probably more natural with the backpack. I don’t know if Los Gatos comes with GPS, which is something I liked a lot of the Scouter, especially if you want to sample multiple points. The SPF lite software from the Scouter is easy to work with and very useful to see real-time what is going during chamber runs, which is helpful to adapt to chamber deployment times or identify measurements that did not go well for x or Y reason. SPF allows you to chose from linear, Hutchinson and Moiser and exponential fittings. You can also work with the raw data and re-do field calculations if needed. In my case, I created a code to take a reprocess the raw data to fit my specific needs. Nothing too fancy. I will be happy to share it if you want.
One piece of advice, besides the thermometer for the chamber, get a stopwatch with a pressure sensor or another device with that capability because you’ll need to input barometric pressure as well into the software to proceed with the calculation of each chamber flux (or may need it for post-processing calculations).
I have not heard about the methane pump issue before but have not seen indications to suspect the measurements were compromised either. I have witnessed methane being uptake multiple times.
Please feel free to contact me if you want to know more details on the setup and data post-processing. I’ll be happy to share what I know about the instrument, chamber designs and how I used the system. Unfurtanetly, only one pub with the scouter (https://doi.org/10.1016/j.scitotenv.2020.136920), but others are the way.
Cheers,
Jorge
Hi Jorge A Villa Thanks very much for your detailed answer, and I hope you are doing well in your new position! Cheers, Erik .
You can also consider the LI-COR LI-7810 - https://www.licor.com/env/products/trace_gas/LI-7810 . This has an operating temperature range down to -25 C. Please contact me for further details.
Hi Graham Leggett, Thanks for the reply. We will be using the LI-COR LI7810 multiplexed for some lowland chamber work in peatlands. As I understand, the issue with the 7810 for high elevation work is that it can't function effectively at low pressures associated with very high elevations. Any new guidance on this from your technical team?
Hi Erik Lilleskov
methane emissions from the GasScouter pump are generally negligible for soil flux studies. The pump off-gassing is specified on the datasheet (