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.
Little is known about sturgeon mortality sources outside management of the White Sturgeon recreational fishery. Mortality has been observed throughout the SFBDE with increased reporting over the past several years. Much of which is concentrated (but not exclusively) in the Carquinez Strait; a narrow strait linking known sturgeon feeding grounds and vital corridor which all SFBDE sturgeon must pass to access spawning grounds. Adult sturgeon populations in the SFBDE are difficult to estimate in part due to unknown rates of mortality, outside the recreational fishery. Specific, non-angling mortality data and sources are needed to develop management strategies that that lead to robust abundance estimates ensuring persistence of these public resources. This project aims to dentify and enumerate non-fisheries sturgeon mortality in the San Francisco Bay Delta Estuary (SFBDE), specifically the Carquinez Strait. We plan to determine population characteristics of observed mortality, age structure and migration patterns/habitat use of collected sturgeon. We will also engage the local community through outreach efforts to investigate the public perception of sturgeon mortality in SFBDE and increase participation in our study.
Chinook Salmon (Oncorhynchus tshawytscha) populations in California are in decline due to the combined effects of habitat degradation, water diversions, and shifting climate regimes. This project uses archival tissues (otoliths, vertebrae) from modern and ancient spring-run Chinook Salmon to understand how shifts in migration timing and habitat use allowed salmon to cope with highly variable environmental conditions. We will learn how salmon responded to the recent drought and flood periods (2012-2020 CE), the California Gold Rush Period (~1835-1870 CE), the Little Ice Age (~1560-1780 CE), and the Megadrought Period (~1200-1410 CE). This effort will provide the insights needed for developing climate-adapted conservation actions to support salmon into the future.
The Sacramento-San Joaquin Delta (Delta) faces a serious threat from the recent proliferation of cyanobacterial harmful algal blooms (cyanoHABs), particularly due to the production of high levels of cyanobacterial toxins. These blooms jeopardize water quality and pose a significant risk to air quality when toxins are released as particles in a process known as aerosolization. When people inhale these aerosols, it can trigger an inflammatory response, yet the specific form in which toxins are aerosolized remains unknown. Thus, an improved understanding of cyanobacterial toxin aerosolization mechanisms has significant human health implications. To assess the public health risks associated with airborne cyanobacterial toxins, the project examined the size distribution of cyanoHAB aerosols and the factors influencing their aerosolization. They also investigated the role of nutrient enrichment in cyanoHAB growth, cyanobacterial toxin production, and cyanotoxin aerosolization through a combination of laboratory and field experiments.
Project Objectives
1. Investigate and quantify the production of primary spray aerosols during cyanoHABs
2. Assess the linkage of nutrient enrichment, phytoplankton community composition, toxin production, and cyanoHAB aerosol formation
This project addresses a pressing environmental and public health concern. The data can be used to protect vulnerable communities living near affected bodies of water and inform ways to mitigate the adverse impacts of cyanoHABs on the Delta’s environmental and public health.
This research improves Delta-specific human exposure guidelines to cyanoHAB aerosols by providing data essential for implementing effective public health measures, including recommendations on mask usage and understanding the expected way aerosols travel through the air from the shoreline. Their investigation into the relationship between nutrient availability, cyanoHABs growth dynamics, toxin production, and aerosol formation will offer valuable insights for management efforts aimed at regulating algal blooms to improve both water and air quality outcomes. Ultimately, this research will strengthen state agency responses to human illness associated with cyanoHABs and toxin exposure.
The foundation of conserving a species is monitoring its abundance and habitat. This proposed work has three objectives which will help monitor green sturgeon abundance and understand green sturgeon habitat selection. These objectives build on 12 years of work to support the recovery of green sturgeon. The first objective is to continue the annual green sturgeon spawner census, while also improving our methods. This census is the main piece of information used in monitoring and assessing the Delta resident green sturgeon population. The second objective is to assess spawner site selection and habitat use which will help better understand sturgeon environmental needs so that restoration can better target those needs. The third objective is to assess the relationship between spring flow rates, temperature, and number of spawners observed, which will help managers better understand sturgeon flow cues and improve the accuracy of our spawner census.
