Mapping Salinas River Riparian Habitat

This study documents the dramatic decline of riparian habitats along the Salinas River, with particular consequences for the predominantly agricultural and Latino communities of King City and South Salinas. Though comprising just 0.8-2% of western U.S. landscapes, these habitats are ecological lifelines - supporting over half of regional wildlife while providing critical water resources (USDA, 2011) . Our findings reveal a troubling paradox: the very communities maintaining California’s $8 billion agricultural industry face disproportionate environmental burdens, as expanding farmland consumes riparian buffers and contaminates groundwater with nitrates - a crisis prompting Monterey Waterkeeper’s leadership in the Clean Water Coalition.

This study addresses three key research questions:

1. 1. How has the extent of riparian areas along the Salinas River changed over time?
   2. How can aerial photography and remotely sensed data sets be leveraged to monitor these changes? and
   3. Which areas along the Salinas River are most in need of conservation efforts?

As revealed by the analysis of digitized aerial photography and remotely sensed data, the most severe habitat losses (32.6% in King City [1994-2002]; 30.6% in South Salinas [1984-1998]) correlate directly with disappearing green spaces that once provided cooling shade, flood protection, and recreational access for farmworker families. This represents both an ecological crisis and an environmental justice issue - while corporate agriculture profits, frontline communities lose vital natural infrastructure and face heightened exposure to pesticides and water contamination. The remaining riparian corridors, now narrowed by agricultural expansion, represent the last accessible natural spaces for these underserved populations.

It is important to note that the layers of the following maps take varying shapes due to the varying extents of the aerial photographs which were digitized to produce them.

Data layers before 2007 are digitized aerial photographs, while those from 2007 and after are classified LandSat data.

This interactive map displays historical riparian vegetation along the Salinas River in two locations: King City and South Salinas. The map shows vegetation extent across multiple time periods from 1931 to 2022. Layers are color-coded by year, with darker green representing older data (1930s-1940s) and lighter yellow-green representing more recent data (2017-2022). Use the layer control panel on the right side to toggle individual years on and off. Click on vegetation polygons to see the year and location. The color legend on the bottom right shows the year associated with each color for both King City and South Salinas locations.

 

These findings underscore the need for targeted conservation efforts to mitigate further loss. Recommendations include reinforcing riparian boundaries, extending existing habitats to enhance ecological functionality, and fostering collaboration among stakeholders—such as conservation organizations, local governments, and agricultural industries—to establish consistent definitions and management practices.

Student Team: Luke Davidson¹, Briana Guingona¹, Sophia Harvey¹, Ava Pape¹
Mentors: Iris Stewart-Frey¹, Natalie Herendeen², Chelsea Tu²
Santa Clara University Department of Environmental Studies and Sciences¹, Monterey Waterkeeper²

 

References

Aerial Photographs from UCSB’S FrameFinder 

LandSat data from NASS’s CropScape