Standard List Example Developed by the States
Standard lists can provide a useful and consistent starting point, but you should keep in mind that no list is complete. Below is an example of a standard list of candicate causes used in Mississippi.
Table. Standard List of Candidate Causes Used for Stressor Identification in Bogue Homo, Mississippi
| Candidate Cause | Available Indicators |
|---|---|
| Oxygen concentration and oxygen demand | Alteration to photosynthesis/respiration balance Decrease in oxygen and increase in oxygen demand Temperature alteration Alteration to natural flow regime Increase in organic enrichment Disruption of nutrient cycles |
| Organic carbon | Increase in organic enrichment Change in food source Alteration to photosynthesis/respiration balance characteristics Decrease in oxygen and increase in oxygen demand |
| Nutrients | Disruption of nutrient cycles Alteration to photosynthesis/respiration balance characteristics Decrease in oxygen and increase in oxygen demand Change in food source characteristics |
| Temperature | Alteration to thermal regulation Alteration to photosynthesis/respiration balance characteristics Decrease in oxygen and increase in oxygen demand |
| Turbidity | Increase in amount and duration of suspended sediment Alteration to natural flow regime Decrease in suitable in-stream habitat Alteration to channel morphology Decrease in riparian vegetation |
| Habitat | Alteration to natural flow regime Decrease in suitable in-stream habitat Decrease in riparian vegetation Alteration to channel morphology Increase in suspended and deposited sediment Change in food source characteristics Decrease in suitable floodplain habitat Temperature alteration Alteration to groundwater interaction |
| Conductivity, total dissolved solids (TDS) and chloride | Increase ion concentrations Alteration to natural freshwater/saltwater interaction |
| pH | Increase in alkalinity or decrease in hydrogen ion activity Increase in acidity or hydrogen ion activity |
| Toxic Substances | Increase in toxic substance concentrations |
References
- Adapted from MSDEQ (2005) Stressor Identification for Bogue Homo. Mississippi Department of Environmental Quality, Jackson MS.