Reports

This report is to compare respiration results of soil respiration from a forced diffusion chamber and ecosystem respiration partitioned by our L3 flux gap-filling/processing.

We installed an Eosense forced diffusion chamber sn FD20160001 at Bouldin Alfalfa on 2018-07-12. It is installed under the tower (white sensor in photo below), where the alfalfa is trimmed by hand as close to mow date as possible. The sensor has been brought back to the lab a few times for testing because it did not seem to be turning on properly after power-cycling.

The alfalfa field is generally mowed by tractor (maybe a rotary mower) 5-7 times March through October. The mowing on 2019-01-30 was done by sheep on the field for a few days.

Figure 1. Daily averages of ecosystem respiration and soil respiration. Dots indicate mowing dates of the field. In general, ecosystem respiration decreases after mowing, and there is a spike in soil respiration.

Figure 2. 30-minute values of ecosystem respiration and soil respiration. Dots indicate mowing dates of the field.

Figure 3. We tried three different partitioning methods for calculating ecosystem respiration: linear, Reichstein, and ANN night. We partitioned 30-minute data, and I've graped daily averages here. Dots indicate mowing dates of the field.