Mud Daubers and Wicked Storms; Researchers Battle the Elements to Make Sure Instruments Work Properly
This is the second in a series of field notes submitted by Benjamin Runkle, assistant professor of biological and agricultural engineering, and other members of his research team. This summer Runkle, a post-doctoral researcher and four students – two graduates and two undergraduates – are working in eastern Arkansas, where they have set up instruments to measure water use, soil and water chemistry and methane production from a rice field. They are seeking ways to reduce water consumption and reduce heat-trapping carbon emissions.
In my first field note I mentioned some of the natural sources of challenges to maintaining a continuous instrument record. We have birds ‘gifting’ us nutrients, paddy water to wade through, and natural wear and tear. In this note I will describe two more challenges we’ve encountered. These natural events influence our instruments by delaying and frustrating our maintenance visits.
In late May our group planned a big field day with a long to-do list. We needed to install a washer system for one of our gas analyzers, install some soil oxygen probes, start the undergraduate summer researchers on some field surveying methods, test a few broken pieces, move solar energy sensors away from other instruments to prevent interference, and install lightning rods onto the towers holding these instruments so they wouldn’t fry in a thunderstorm. We also had a few colleagues stop by to compare notes and work on other nearby systems. After a late lunch break – stretching everyone’s stomachs and energy reserves long enough – we came back to the field at 3 pm. The students were sent out with a pH probe to look at water quality in the rice field. A
ladder was installed by the tower to put up a lightning rod. Within an hour the sky grew darker and darker. I downloaded a weather radar App to my phone and wow – the storm comes closer and closer. The students were messaged – Get to the edge of the field! We had to quickly assess – no time for the lightning rod this field visit – despite the oncoming storm! We really had just enough time to gather all equipment, dash to the vehicle, and clear out of the open spaces. Fortunately nothing was hit – this time – by lightning and the rain and wind didn’t twist up any instruments.
Another challenge two weeks later – wasps in the instrument box! We have a few different monitoring points around our site. This scatter helps us take account of spatial variations in the field. Our wind-related sensors also record a signal from the direction they “see” – so the wind must come off the field. We therefore have one tower on each of the north and south sides of the field to make sure we see information about turbulence from the field no matter which way the wind blows. I went over to our southern tower with Kosana, my group’s post-doctoral researcher. We download data from a datalogger containing data storage cards and input wires helping to record temperature, wind, and soil numbers. Within the week since our previous visit, a group of “mud dauber” wasps set up a home the size of a baseball inside
our box. I carefully and quickly knocked it out of our box and dropped it into the paddy water. The wasps were too surprised to rise up and fight back. A great reminder to properly seal the box – where the wires come in there is often just enough space for insects to also enter. We’ll be looking our next visits for these nests – I’d much rather catch them young than mature!