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Support healthy, connected ecosystems.

The river is an important ecosystem that supports a variety of plant and animal life throughout the highly urbanized landscape of LA County.
KCET Departures, South L.A. Willow Street, 2010. Source License: CC BY-NC-ND 2.0.

The LA River watershed sits within one of the world’s most diverse Mediterranean biodiversity hotspots and along the Pacific Flyway.

Due to urbanization, the region has the largest number of endangered and threatened species and species of special concern in the contiguous 48 states.1USGS Western Ecological Research Center, Bioregions of the Pacific U.S. The river ecosystem has been altered from its historic state, first through agriculture and irrigation and later through channelization. In community meetings and surveys, 52% of participants said the issue most important was protecting vulnerable plants and animals. Planning and development efforts along the river must create habitat areas large enough to support native functioning ecosystems.


Steps that should be taken to achieve the goal

LA River Ecosystems Need
LA River Ecosystem Needs Ruler.
OLIN, 2019.

Needs: Ecosystems

In an urban environment like LA, sustaining healthy ecosystems requires protecting areas with high biodiversity; enhancing, expanding, and adding habitat in strategic locations; and creating linkages between habitat areas.

Need for ecosystems was evaluated by combining the need to protect and manage existing habitat areas, large areas with remaining native vegetation, with the need to expand these habitat areas through habitat buffers. Linkages, potential connections between habitat areas, such as LA River tributaries and confluences were also used to evaluate the need for ecosystem improvements. Like ecosystems themselves, data on existing habitats is always evolving and other areas may also be of high importance. Additional data should be included as it becomes available and site-by-site evaluation is needed to confirm existing ecological conditions. As the map shows, all areas have need in LA County for healthy, functioning ecosystems.
LA County Map
LA County Ecosystem Need.
OLIN, 2021.
CALVEG Regional Dominance types from the USDA Forest Service were used to classify existing areas as predominantly urban or barren, native or natural, or invasive vegetation. Areas with native or natural landcover were considered habitat areas and were designated as very high need due to the importance of managing these few remaining areas of native plant habitat. Areas that were agricultural or barren were categorized as general need and areas that were predominantly urban were categorized as having no need. Areas not categorized as habitat may still have an overall very high need if they are near a strategic location such as an existing habitat area buffer, linkage or confluence, or are unprotected. More locally, communities known to have less access to nature and a high potential for ecosystem improvements should be prioritized.
Areas closest to existing protected habitat areas (within 1,000 feet) that could help further buffer core protected habitat areas were categorized as having very high need. Areas further than 1,000 feet were categorized as general need.
Missing linkages are areas without connectivity, but based on their location, are critical to improving ecosystem connectivity. These linkages were identified by the 2008 South Coast Missing Linkages Project. Tributaries and confluences can also provide opportunities for species to move throughout the LA Basin. Areas closest to a missing linkage, tributary, or confluence were categorized as very high need. Areas up to 5,000 feet were categorized as general need, and areas further than 5,000 feet away were categorized as no need.
Unprotected areas are vulnerable to development and are less likely to sustain habitat areas over time. Ecosystems that are in areas that are unprotected have very high need. Protected areas, which were categorized as general need, were identified based on the California Protected Areas Database.

Case Studies

Atlantic Park De Las Llamas, Santander, Spain

Atlantic Park de Las Llamas is located in the center of Santander, Spain. This park space transformed a former trash dump site into an ecologically rich urban park. The park utilizes a three tier design strategy to create different habitat types throughout the project. These tiered ecosystems remove pollutants from the runoff and provide infiltration opportunities in the heart of the city.

Lessons Learned

  • Success came from the project’s ability to blend the public and urban uses with the necessary ecosystem functions
  • Highly designed public space has proven to operate successfully in terms of ecosystem functions
  • Providing access from all points of the surrounding neighborhoods and communities maximized its urban potential
  • The park successfully utilized geometric forms for waterway/waterfront design of public space
Photo of walkway and pedestrian bridge crossing wetland-inspired pools.
Atlantic Park de Las Llamas is comprised of multiple trails that meander through the different ecological pools where users can experience design elements that bolster ecosystem functions.
Tiia Monto, Parque de las Llamas in Santander, 2016. Source License: CC BY-SA 3.0.
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