Automated sample combustion in cover crop studies
27/01/2025
At a glance
> The Hidex 600 OX has been used to study the fate of 14CO2 in cover crops to investigate carbon capture.
> Using the automated sample oxidizer, the University of Copenhagen was able to prepare samples of released 14C for liquid scintillation counting.
> The oxidizer can combust up to six samples in sequence, providing higher throughput than manually fed models.
Investigating the eFate of 14CO2
Cover crops are used between main crops to improve soil health, trapping carbon from the air, which can fight climate change by storing carbon in the soil. However, not much is known about how different types of cover crops affect the amount of carbon captured. A study by Engedal et al. at the University of Copenhagen used the Hidex 600 OX to investigate the fate of 14CO2 in four cover crops with different root morphologies and carbon-to-nitrogen ratios: winter rye, oilseed radish, chicory, and hairy vetch.
Preparing samples of 14C for liquid scintillation counting
The Hidex 600 OX is a fully automated catalytic combustion unit designed for sample preparation. Many older models of oxidizers require samples to be manually fed into the chamber for combustion, but through automation, the 600 OX efficiently manages the combustion process of six samples in sequence at 900 °C (1600 °F). The released 14C is automatically collected, sealed, and aspirated into vials for liquid scintillation counting, eliminating manual user input to increase productivity.
The study measured how much carbon entered the soil through the roots and through other processes like root excretions. To measure the activity of 14C, the samples were first combusted in the 600 OX to capture 14CO2 for counting. Results found that the amount of carbon lost through roots varied. Cover crops with more branching roots lost 22 % of their carbon through root activity in the topsoil compared to those with less. It was also found that certain crops are more efficient at forming organic carbon in the topsoil than others.
Find out more
To read the whole study by Engedal et al., click here. To learn more about the Hidex 600 OX, click the button below to speak to a product specialist directly.