Forests breathe. For real. Forest soils are collectively one of the largest sources and sinks of CO2 on the planet, absorbing and emitting millions of tons of the greenhouse gas each year.
While terrestrial ecologists have a good handle on anygiven forest's rate of respiration, its discrete sources of CO2 therein (e.g. autotrophic plant roots, heterotrophic microbes) and environmental variables to which they most respond (e.g. temperature, rain, time of day), were still somewhat of a mystery. How in-sync CO2 respired from respective tree "stems" (better known as trunks by non-biologists) had similar question marks ahead of it.
That is, until your boy came through. I designed a set of chambers that take around-the-clock measurements of CO2 and O2 being emitted by multiple natural sources of experimental forest. The patch was at Harvard Forest, and the research was based out of MBL in Woods Hole, MA.
Collecting respiration data every few minutes, from stem and soil sources at once, the chambers produced one of the world's most high-resolution glimpses at how forest's breathe. They also happened to be a thrill to design and build.
The chambers are mechanically actuated with pneumatic pistons. It was an easy design choice: I was already running tubing and solenoids for the gas samples from each chamber, I might as well do the same for their mechanics. From there, most of the system's design challenges revolved around the single problem of moving air.
The experiment's control box housed a custom manifold of solenoids and power relays for air control. I wrote my first ever piece of code to run the chambers' schedule, calling out air paths and batching my gas analyzers' respective data. One of the most haggard pieces of code ever created. Thought I was f@ing Steve Jobs when I wrote it.