Riparian Restoration Strategies at Jalama Canyon Ranch

Rebuilding the Hydrological Cycle and Monitoring Ecological Benefits

Riparian zones play a crucial role in the water cycle by connecting streams with upland areas where rainfall is cycled into surface and subsurface water. In water-limited regions such as California, these areas of hydrologic connectivity also tend to be the most ecologically productive. Healthy riparian zones, or belts of vegetation on the banks of rivers, streams, and other water bodies, are signs of a thriving watershed and provide an impressive suite of benefits to the ecosystem: habitat for a multitude of organisms, carbon sequestration from the increased plant biomass, bank stability, flood and fire mitigation, and more. However, it is estimated that over 70-90% of California's riparian vegetation has been lost [1]. The restoration and regeneration of riparian zones provides an opportunity to improve hydrologic function and increase the ecological vitality and resilience of agricultural watersheds. In 2022 White Buffalo Land Trust (WBLT) initiated a pilot restoration effort at Jalama Canyon Ranch (JCR) designed to expand the riparian zones and begin rebuilding the water cycle. The principles and practices being implemented at JCR are applicable throughout our region.

Pictured above within the blue boundary line is the riparian zone identified for restoration at Jalama Canyon Ranch. Riparian zones stand out from the surrounding landscape, as the presence of water creates unique soil characteristics and vegetation communities. These areas maintain healthy stream channels, and are essential habitat for terrestrial and aquatic biodiversity.

Jalama Canyon Ranch is a diverse 1000-acre landscape located in Santa Barbara County that serves as a living laboratory for WBLT to demonstrate, monitor, study, and teach the restorative potential of regenerative land stewardship. Like many agricultural landscapes in the region, JCR has experienced severe degradation of its riparian zones and now possesses insufficient vegetative cover, a lack of perennially flowing streams, and eroded stream channels. The cumulative effect of these impacts is loss of hydrologic function and diminished supply of onsite water availability for agriculture and native plant and animal communities.  

In October 2022, WBLT initiated restoration efforts at three key locations within the riparian zone in the North Creek watershed at JCR. Funded by the USDA’s Natural Resources Conservation Service Environmental Quality Incentives Program, WBLT received a grant to purchase equipment and material. In partnership with 7th Generation Design, a framework based on regenerative principles was used to design and implement three specific practices with the goal of rebuilding the hydrological cycle and supporting the complementary ecological benefits within the riparian zone.

Revegetation consisted of 17 regionally adapted species established within three zones in the North Creek riparian corridor.

Practices

1) Establishment of a diverse, multi-layered, native plant community:

Riparian vegetation includes a diversity of native plants including trees, shrubs, and grasses that are adapted to water rich environments. A healthy riparian zone consists of multiple ‘layers’ of vegetation, including low lying understory groundcover, an intermediate midstory of shrubs and small trees, and a higher overstory canopy of trees, all supporting increased habitat and shelter. With the help of graduate student volunteers from the UCSB Bren School, the WBLT team planted over 180 native and perennial saplings that will mature into a multi-layer riparian forest adapted to the regional climate.

2) Bank stabilization through vegetation establishment: 

In addition to providing biologically diverse habitats, the presence of perennial, deep rooted vegetation along stream channels holds the soil together, to stabilize stream banks and the adjacent riparian and floodplain soils during periods of high streamflow. We established 17 species selected for their extensive, deep root systems that are adapted to the water-limited climate of the region. To support the establishment of these plant communities prior to the dry season, we installed spring-fed supplemental drip irrigation that will run as needed throughout the rainy season, mimicking the natural patterns of rainfall these native plants are adapted to.

3) Contour plantings to slow overland water flow:

Water flowing down a slope can potentially cause flooding, erode soil, and create rills (shallow channels) and gullies. Planting along a contour, i.e., perpendicular to the slope, creates a natural break in flow patterns, and allows more time for water to slow, spread and sink into the landscape. We designed plant placement and spacing in line with the natural contours of the land to optimize water capture along natural drainage patterns.

Intended Outcomes

These practices were implemented with the intention to create the following ecological impacts:

Rehydrate The Landscape: As we experience climate extremes between drought and intense rainfall [2, 3], it becomes more important than ever that we work to improve the land’s capacity to absorb and store rainfall. Trees, shrubs and grasses slow surface water runoff, and roots create pathways for water to infiltrate deeper into the soil profile, eventually recharging local aquifers. The increase in perennial roots improves soil aggregation, which in turn increases soil’s water holding capacity. This soil-water-bank can serve as a source of water for vegetation during drier periods. During drier months, the deep roots of native vegetation can redistribute groundwater from deeper to shallow soils, creating a moist and cool environment for terrestrial and aquatic wildlife. Tree and shrub canopies release water vapor (evapotranspiration) helping to regulate regional precipitation. 

Reduce Stream Channel Erosion: The changing climate is predicted to shift hydrologic regimes towards higher frequency of extreme flooding events [4], such as those experienced during the atmospheric river in January 2023. Restoring riparian zones may reduce the impacts of extreme flooding events on stream channels. In the absence of riparian vegetation, more runoff can reach the stream channel during storms, resulting in higher streamflows, with strong stream bank erosion and scouring, greater damage to wildlife habitat, and degraded downstream water quality. In addition to slowing surface runoff, riparian vegetation strengthens stream banks by aggregating the soil. Strongly aggregated soil is more resilient to physical erosion, creating structurally stable stream banks during periods of intense streamflows.

Increase Carbon Sequestration: Planting vegetation sequesters carbon by removing atmospheric CO2 through photosynthesis and creating above and below ground biomass. Plant roots secrete sugars, proteins, and other substances (known as root exudates) into the soil that feed a diverse array of microbes living in soil. A healthy and thriving soil microbiome converts discarded biomass into long term stores of carbon in the soil.

Pictured above is projected carbon sequestration from riparian restoration at Jalama Canyon Ranch. These values were obtained from the California Department of Conservation’s Carbon in Riparian Ecosystems Estimator for California (CREEC) tool. We will conduct field measurements to compare with the modeled results.

Improve Wildlife Habitat: We planted 17 regionally adapted species to revitalize the riparian zone, including fruiting natives such Blue Elderberry (Sambucus nigra ssp. cerulea), and Lemonade berry (Rhus integrifolia). By establishing a diverse stand of native vegetation in the upper reaches of JCR, we hope to support increased populations of insects, birds and mammals through increased canopy cover, and improved pollen and forage opportunities. The impact of the riparian areas being restored with native vegetation cannot be overstated. Native plants have evolved to be drought tolerant, have developed their own defenses against pests and diseases, and research [e.g., 5, 6, 7] shows that birds and insects display clear preferences for native plants.

Monitoring Protocol

Detailed observation and meticulous recording of carefully chosen indicators is key to understanding and quantifying the outcomes of these riparian restoration practices. Each plant placed in the ground was geotagged to create a spatial inventory of tree and shrub species and their locations in the riparian zone. This spatial record forms the basis for monitoring ecological impacts in the area. After a review of scientific literature, we have identified a suite of indicators to closely monitor our restoration efforts, beginning with the establishment of baseline conditions in Spring/Summer 2023.

The above table is a preliminary list of indicators we will monitor. The data collected will help quantify the ecological impacts of the restoration practices.

To support the monitoring efforts WBLT will use Irriwatch, a remote sensing platform, to quantify soil moisture, soil carbon and above-ground biomass on a daily basis at a 10m by 10m spatial resolution. This is an excellent, highly detailed dataset to monitor changes at the landscape level, and we are working closely with the Irriwatch team to ground-truth the data by collecting field measurements and data via a network of in-field sensors. We have identified the appropriate technology for this and are exploring research partnerships and funding opportunities to implement the next stage of monitoring in the riparian zone.   

Additionally, in partnership with Grizzly Corps, our team will lead and implement bird counts in partnership with local bird watching groups. With the assistance of our academic partners, we are exploring multiple techniques to monitor insect populations including sweep netting, malaise traps (tent-like traps made of fine mesh) and DNA metabarcoding.

Stay Tuned

Restoration of riparian areas with native plants provides a myriad of positive ecological outcomes, in addition to playing a leading role in connecting people to place. This project gives us the opportunity to demonstrate the impressive resilience of native vegetation. In fact, in light of recent “atmospheric rivers”, we have already observed that the elderberry saplings in particular are taking full advantage of the higher than average rainfall. We are excited to further investigate the role these native trees can play in restoring agricultural landscapes in California through a multi-partner project funded through the USDA’s Climate Smart Commodities grant. We look forward to sharing the practices and carefully monitored resultant benefits through our education and training programs so that others may work to restore these significant areas on their own land, and we invite you to follow our restoration journey via our website and social media!

Riparian corridor plantings after 2023 “atmospheric river” rain events. All plants survived the heavier than average rainfall.