 | Term | Definition |
 | Biota | Data associated with biological organisms |
| Chemistry | Data associated with chemistry, chemical analysis or processes |
| Climate | Data associated with the climate, weather, or atmospheric processes |
| Geology | Data associated with geology or geological processes |
| Hydrology | Data associated with hydrologic variables or processes |
| Instrumentation | Data associated with instrumentation and instrument properties such as battery voltages, data logger temperatures, often useful for diagnosis. |
| Limnology | Data collected from lakes |
| Soil | Data associated with soil variables or processes |
| Unknown | The general category is unknown |
| Water Quality | Data associated with water quality variables or processes |
