Determining Water Residence Time for Large Mesocosms in Utah Lake Using Field Measurements and a CSTR Model
Abstract
We use large, 10-meter diameter mesocosms called "limnocorrals" in Utah Lake to study nutrient cycling and ecological processes. To better understand and characterize the behavior of these mesocosms, we designed a study to quantify water residence time and dilution in the corrals. For this experiment, we used rhodamine as a conservative and instantaneous signal measured with spectrofluorometry, which is sensitive to to a few parts-per-trillion (ppt). This approach provides dilution data over a large range. We modeled water residence time in the corrals using a continuous stirred-tank reactor (CSTR model). We introduced rhodamine to our limnocorral mesocosms and measured concentrations over a period of seven days. Soon after rhodamine introduction, we experienced a storm with high winds and significant wave action that reduced the residence time in the mesocosms. To determine residence time, we fit a CSTR model to the data and found a residence time of less than two days. At the time of submission, we are performing a second experiment hopefully without storm impact. These data inform researchers about the behavior of the mesocosms and how well they isolate their interior water column from the lake. This information, generated using rhodamine tracers and spectroflourometry, is critical for understanding mesocosm environments and experiments.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.H12K0829B