Carbon evolution and active carbon in soil (measurement methods)

General Discussion

Thumb educators

Andriy Herts, Nataliia Herts

submitted 9 months ago.

Hello! I want to start the study of soil. Do I understand correctly: 1. I can measure carbon evolution from soil - soil (on the field, for example)+ chamber+CO2 sensor. After this converts CO2 ppm in kg C m-2 day (don't need of calibration ) 2. I can measure active carbon - example of the soil + chamber+CO2 sensor + potassium permangenate solution (need in calibration) Thanks!

Thumb sam 0645   copy   copy  2

Dan TerAvest

submitted 9 months ago.

1) Using a closed chamber and a CO2 sensor you can measure the rate of CO2 evolution from soils. Using the change in CO2 ppm over a known time, the ideal gas law, and the headspace of the chamber and surface ares of the soil in the chamber, you can calculate the rate of C evolution from soils (kg C ha-1 day-1). It is important to remember that soil moisture content, air temperature, and soil temperature will have significant affects on C evolution rates. It is best to also collect this metadata so that it can be included into data analysis models.

2) You can use the MultispeQ has a spectrophotometer to measure soil active C using a Potassium Permanganate solution. This method will require you to run blanks (protocol: Active Carbon in Soil blank II) and a calibration project (https://www.photosynq.org/projects/active-soil-c-calibration-calibracion-para-c-activo?hl=Soil+Active+C). Directions for sample preparation can be found here: https://www.photosynq.org/projects/new-nuevo-soil-active-c-c-activo-de-suelos?hl=Soil+Active+C

Default avatar

Itay cohen

submitted 8 months ago.

Hi Dan, which CO2 sensor can be attached to the multispeQ? thanks Itay

Thumb sam 0645   copy   copy  2

Dan TerAvest

submitted 8 months ago.

The best CO2 sensor that we have found to connect to the MultispeQ is the K-30 sensor (http://www.co2meter.com/products/k-30-co2-sensor-module). It has a quicker response time than other sensors we have tried and is pretty inexpensive.

Default avatar

Itay cohen

submitted 8 months ago.

thanks!

Thumb educators

Andriy Herts, Nataliia Herts

submitted 9 months ago.

Dan, thank you. I will be waiting of PQ V.1.0 for spectrophotometer measure of active CO2 and continue to create the chamber for carbon evolution from the soil.