Projecting the Multiple Benefits of Land Cover Change in the Sacramento-San Joaquin River Delta • DeltaMultipleBenefits

Introduction

The DeltaMultipleBenefits R package serves as an open-source, science-based framework for estimating the net impacts of scenarios of landscape change on multiple metrics of interest. It is intended to support land use planning, management, conservation, and community engagement in the Sacramento-San Joaquin River Delta by identifying potential benefits and trade-offs of proposed or anticipated changes in land cover.

Your help is needed! We are currently seeking input on approaches to developing tidal wetland restoration scenarios. Please see our recent article for more information.

Installation

You can install the development version from GitHub with:

# install.packages("devtools")
devtools::install_github("pointblue/DeltaMultipleBenefits")

How to use

This package provides tools for evaluating land cover rasters supplied by the user to estimate the magnitude of the benefits associated with each landscape and the differences in benefits among landscapes, such as between current baseline land cover and a proposed or anticipated alternative land cover.

Benefit Categories and Metrics

The benefit categories currently addressed include: Agricultural Livelihoods, Water Quality, Climate Change Resilience, and Biodiversity Support. Each category is represented by multiple metrics:

All metrics are currently one of two types:

simple metrics: quantitative values or qualitative scores assigned to each land cover class and summarized over the entire landscape
spatial models: models that require information about the spatial distribution of land covers to estimate a total value, such as the total suitable habitat estimated from a species distribution model

All simple metrics and species distribution models that have already been developed for this framework are available for download:

Metrics Data for Quantifying Multidimensional Impacts of Landscape Change in California’s Sacramento–San Joaquin Delta. DOI: 10.5281/zenodo.7504874 (also included in the DeltaMultipleBenefits package)

Distribution models for riparian landbirds and waterbirds in the Sacramento-San Joaquin Delta. DOI: 10.5281/zenodo.7531945

This framework is still in development and designed to readily incorporate additional species, models, data, and metrics. Please contact us to collaborate on incorporating additional metrics or data.

Scenarios & Alternative Landscapes

By comparing landscape totals for each metric estimated from a baseline landscape and alternative landscapes representing proposed or anticipated changes, the expected direction and magnitude of the net change in each metric is estimated. In the initial development of this framework, we built simple alternative landscapes representing changes driven by one or two individual drivers of landscape change, allowing evaluation of their individual impacts. However, more complex and realistic scenarios of future landscape change can also be evaluated.

All landscapes that have already been developed for this framework are available for download, including a baseline landscape, a restoration landscape representing Delta Plan restoration targets for non-tidal wetlands and riparian habitat, a perennial crop expansion landscape, and a combination of restoration and perennial crop expansion.

Baseline and projected future land use and land cover in the Sacramento-San Joaquin Delta (including predicted presence of focal taxa under baseline conditions)

Evaluating New Scenarios

This package includes a vignette that serves as a tutorial outlining the major steps of analyzing alternative Delta landscapes and comparing them to each other, including:

Preparing new landscape scenarios for analysis
Summarizing the net change in the total area of each land cover class
Estimating the net change in simple metrics
Estimating the net change in metrics informed by spatial models

Supporting Information

Dybala KE, Sesser K, Reiter M, Hickey C, Gardali T. 2023. Final Project Report: Trade-offs and Co-benefits of Landscape Change Scenarios on Bird Communities and Ecosystem Services in the Sacramento-San Joaquin River Delta. Point Blue Conservation Science, Petaluma, CA

Dybala K, Sesser K, Reiter M, Shuford WD, Golet GH, Hickey C, Gardali T (2023) Priority Bird Conservation Areas in California’s Sacramento–San Joaquin Delta. San Francisco Estuary and Watershed Science 21(3). DOI: 10.15447/sfews.2023v21iss3art4

Dybala KE, Reiter ME, Hickey CM (In press) Multiple-benefit Conservation in Practice: A Framework for Quantifying Multi-dimensional Impacts of Landscape Change in California’s Sacramento–San Joaquin Delta. San Francisco Estuary and Watershed Science.

Supplemental Spatial Data for Quantifying Multidimensional Impacts of Landscape Change in California’s Sacramento–San Joaquin Delta. DOI: 10.5281/zenodo.7672193

Funding Statement

These data were originally developed as part of the project Trade-offs and Co-benefits of Landscape Change on Bird Communities and Ecosystem Services in the Sacramento–San Joaquin River Delta, funded by Proposition 1 Delta Water Quality and Ecosystem Restoration Program, Grant Agreement Number – Q1996022, administered by the California Department of Fish and Wildlife.

A second phase of development is currently underway, Trade-offs and Co-benefits of Landscape Change in the Sacramento-San Joaquin River Delta: Phase II Tidal Wetlands and Restoration, funded by the Water Quality, Supply, and Infrastructure Improvement Act of 2014 (Proposition 1, CWC § 79707), grant agreement number Q2296017, administered by the California Department of Fish and Wildlife.