How do we classify wetlands in California?
The California Aquatic Resource Classification System or CARCS is used to classify wetlands in the California Aquatic Resource Inventory (CARI). Wetland managers and scientists from across the state developed CARCS to support effort to track changes in the diversity, distribution, abundance, and condition of wetlands throughout the state. CARCS is based on existing federal classification systems that have been tailored to fit the needs of California. CARCS recognizes 6 classes of wetlands among 2 major categories. CARCS allows wetlands to be further classified based on their landscape connection, naturalness, vegetation, hydrology, and substrate. CARCS can be translated into federal and regional classification systems. For more information on the development of CARCS and wetland definitions visit the CARI info page.
- The first step in CARCS is to digitize a given feature using remotely sensed imagery (ex. aerial or satellite photos) and ancillary data (ex. slope, soil) and decide which major category and class it belongs to. Landscape connection (position in landscape relative to other areas) designation is highly recommended if discernible from the data sources.
|REQUIRED CLASSIFICATION OBTAINED THROUGH REMOTE SENSING|
|Non-wetland Open Water||LACUSTRINE||Same as Associated Wetland|
|MARINE||Intertidal||Cove, Embayment, Exposed Shoreline|
|Subtidal||Cove, Embayment, Exposed Shoreline|
|Wetlands||DEPRESSIONAL||Floodplain||Defined outlet, Undefined outlet|
|Non-floodplain||Defined outlet, Undefined outlet|
Break in slope
River Valley Mouth
|Structural Basin||Embayment-Rocky Headland,
Lagoon, Dune Strand/Dammed
- The next step is to collect more specific information on land use and vegetation characteristics. These data are recommended, but not required as it may be difficult to discern from the imagery or other data.
|REMOTE SENSING, RECOMMENDED|
|ANTHROPOGENIC INFLUENCE||VEGETATION MODIFIER|
|WATER SOURCE / HYDROPERIOD|
Ditched / Drained
|SUBSTRATE AND BANK|
|Filled / Graded
|AGRICULTURE OR OTHER USE|
Harbors / Marinas / Ports
Row or Sown Agriculture
- The final step is to collect, if possible, hydrology and substrate data that help further characterize the wetland. These data are also difficult to interpret based on the imagery, though indicators can be used and can sometimes be found in other data sources. If these resources are not available, field methods are likely necessary.
|HYDROLOGY MODIFIERS||SUBSTRATE MODIFIER|
|TIDAL||RIVERINE OR FLOW-THROUGH|
|FLOWING||LENTIC OR CLOSED-BASIN|