The proposed project is driven by the need to understand how land use has changed historically in California's Central Valley due to various drivers including environmental changes and socio-economic developments. Given the region's dependency on agriculture and its vulnerability to climate change—marked by shifts in precipitation patterns and water availability—it's crucial to model these dynamics accurately to forecast future conditions and plan effectively. Using Agent-Based Modeling (ABM) provides a sophisticated means to dissect past interactions between land use and environmental factors at a granular level. This historical understanding is pivotal as it sets the stage for projecting future scenarios. Additionally, the integration of future hydrology data generated from the CalSim3 model and socio-economic scenarios allows for a comprehensive analysis of potential future states. This analysis aims to explore strategic land use modifications that can meet future socio-economic goals under varying water availability scenarios.
This research supports several key science actions, making it highly relevant to current policy discussions. It provides actionable insights into large-scale experiments (Science Action 1C), assesses the impact of climate on ecosystems (Science Action 6A), and explores water allocation strategies (Science Action 6E), thereby equipping policymakers and stakeholders with the necessary tools for informed decision-making. These decisions are crucial for maintaining ecological flows and ensuring the longterm viability of both the agricultural sector and the natural ecosystems upon which they depend.
As source areas of snowmelt, Sierra Nevada headwater streams are the origin of water that feeds the Delta, but their response to climate change is not well understood. By utilizing long-term data and modeling future responses, we build a tool to reduce scientific uncertainty about Delta water supply and water quality in a changing climate. By incorporating indigenous cultural values, we create a fully integrated shared vison of the future of the Delta in a changing climate, including mapping which areas are most vulnerable and in need of conservation or restoration.
The project objectives are: 1. Utilize and expand on existing water quality and biological monitoring networks in Sierra Nevada headwaters streams to construct models of ecosystem dynamics with respect to climate induced stress impacts on benthic communities, water quality, and nutrients. 2. Construct an oral-history-derived framework of indigenous cultural values of Delta headwaters systems and how science and indigenous values can interact to improve management outcomes. 3. Utilize and expand on existing platforms for dissemination of forecasting tools and model outputs to water managers as well as both scientific and non-scientific communities in the Delta headwaters.
The primary objective of this project is to develop alternative rearing methods for the critically endangered Delta Smelt, endemic of the San Francisco Bay Delta (SFBD). Current hatchery practices have struggled to overcome domestication effects in captive-reared fish, resulting in reduced fitness and lower survival rates when released into the wild. Additionally, the resource-intensive nature of Delta Smelt rearing and the associated costs present challenges to scaling up production. While the UC Davis Fish Conservation and Culture Laboratory (FCCL) has made significant strides in producing Delta Smelt for supplementation, meeting long-term population recovery goals will require more efficient and effective rearing methods. This project aims to improve post-release survival rates and overall fish production by exploring more naturalized and cost-effective rearing environments.
To achieve this, we will investigate the use of local impoundments (enclosed natural environments that provide more variable and realistic conditions) compared to traditional hatcheries for increasing Delta Smelt production and fitness. We will rear Delta Smelt in enclosures placed within these impoundments and compare key fitness-determining traits, such as survival, growth, temperature susceptibility, hypoxia tolerance, and antipredator behavior, to those of fish reared under controlled conditions at the FCCL. Additionally, we plan to transfer practices developed in other successful fish supplementation programs (e.g. Razorback Sucker and Rio Grande Silvery Minnow) and develop methods for natural spawning within these impoundments by introducing spawning substrates and closely monitoring spawning activity during the natural season.
The California Department of Parks and Recreation, Division of Boating and Waterways (DBW) operates a control program for both floating and submerged IAV. This project is an IEP Synthesis effort that will integrate a historical and ongoing dataset of the Delta IAV coverage and DBW IAV treatment records for the past 14 years. This study seeks to determine if treatment efficacy differs across space (e.g., different habitat types) and time. It will assess the impact of IAV control effort on the distribution, growth rate, spread and persistence, and species richness and community composition of the IAV communities. Gaining such understanding on the relationship between IAV treatment and IAV distribution, coverage, and species composition is an urgent management issue for the Delta, given the sharp rise in coverage of IAV from 9000 acres in 2004 to 12,500 acres in 2014 and its likely impact on the shallow-water habitat.
The objectives of this study are:
1. What are the rates and patterns of spread for floating IAV? Do the rates of spread into water or marsh differ? Where do these floating IAV persist and what mechanisms can be linked to their ability of persistence? If there are specific locations that promote persistence, for example over-wintering nurseries, could they be targeted for removal?
2. Has treatment for both water primrose and water hyacinth been successful in reducing species cover over the last 15 years? If so, was treatment effective in reducing density, reducing growth rates, slowing down expansion, and therefore changing distribution of target species? Does treatment efficacy change over different habitats and through time?
3. Does herbicide control of target submerged IAV species reduce density, growth rates, slow down expansion and persistence, and change submerged community composition towards native species? Does treatment efficacy change over different habitats and through time? Does it change the patch size and distribution?
