Springs, seeps, and tinajas are critical surface water sources in the arid and semi-arid Sonoran Desert and Apache Highlands ecoregions. They are the primary connection between groundwater and surface water, and are important water sources for park plants and animals.
"Springs" are reliable perennial and quasi-perennial sources of surface water. "Seeps" emit water from underground that does not always reach the surface. Tinajas, or "small jars" in Spanish, are perennial and quasi-perennial surface waters found in bedrock. They are fed by springs and/or precipitation. Many seeps and springs feed tinajas and other surface waters.
Knowing about the status and trends of springs, seeps, and tinajas can provide park managers with early warning about potential threats to plants and animals that rely on these waters for survival. In some cases, identifying the condition of springs and seeps is also important for human health and safety. Knowing whether to expect surface water to be available at a given site is important to park visitors planning trips into the backcountry.
Understanding patterns in the amount and quality of water in springs, seeps, and tinajas—and their associated plants and animals—will help the Sonoran Desert Network to evaluate the overall status of water resources in network parks.
Measurements and ObjectivesAt selected sites, the network measures:
- Water depth
- Number of days spring is dry and wetted extent
- Benthic macroinvertebrates (aquatic insects)
- Core water quality parameters: water temperature, dissolved oxygen, instantaneous flow, specific conductance, pH, and turbidity
- Primary nutrients (concentrations of total N and total P)
- Biological condition (biochemical oxygen demand, E. coli)
- Metal concentrations
- Riparian plant communities
- Riparian plant species and lifeforms
The objectives of this monitoring are to determine the status and long-term trends in:
- spring discharge
- core water quality parameters
- community composition of macroinvertebrates
- persistence of water
- richness, extent, and abundance of common spring vegetation