Castle Lake Limnological Research Station
in the Shasta-Trinity National Forest, Northern California, USA Contents
Current weather
CA - Mount Shasta
- Clear sky
- Temperature: 7 °C
- Wind: Variable, 5.6 km/h
- Pressure: 1015 hPa
- Rel. Humidity: 57%
- Visibility: 16.1 kilometers
Fri, 2008-05-09 00:56
Dissolved Inorganic Carbon (DIC)
The DIC measurement is used to determine the original 12C concentration so the Primary Productivity Rate (PPr) can be calculated. In order to calculate primary productivity, the researcher needs to know both how much 14C was added and how much 12C is available to the algae. A water sample for each depth is injected into a vacuum test tube of known volume. A small amount of acid is then injected to convert all inorganic carbon into carbon dioxide. Back in the laboratory at UCDavis, carbon dioxide concentration is measured with an infrared detector. The absorbtion of infrared light is proportional to the amount of carbon dioxide present.
There are many possible carbon contaminants, including air, skin, and many other substances in the lab, so one must be careful while doing this analysis.
