"The Reference Genome Of The Kidnapper Ant, Polyergus Mexicanus".

Polyergus kidnapper ants are widely distributed, but relatively uncommon, throughout the Holarctic, spanning an elevational range from sea level to over 3000 m. These species are well known for their obligate social parasitism with various Formica ant species, which they kidnap in dramatic, highly coordinated raids. Kidnapped Formica larvae and pupae become integrated into the Polyergus colony where they develop into adults and perform nearly all of the necessary colony tasks for the benefit of their captors. In California, Polyergus mexicanus is the most widely distributed Polyergus, but recent evidence has identified substantial genetic polymorphism within this species, including genetically divergent lineages associated with the use of different Formica host species. Given its unique behavior and genetic diversity, Polyergus mexicanus plays a critical role in maintaining ecosystem balance by influencing the population dynamics and genetic diversity of its host ant species, Formica, highlighting its conservation value and importance in the context of biodiversity preservation. Here, we present a high-quality genome assembly of P. mexicanus from a sample collected in Plumas County, CA, USA, in the foothills of the central Sierra Nevada. This genome assembly consists of 364 scaffolds spanning 252.31 Mb, with contig N50 of 481,250 kb, scaffold N50 of 10.36 Mb, and BUSCO completeness of 95.4%. We also assembled the genome of the Wolbachia endosymbiont of P. mexicanus - a single, circular contig spanning 1.23 Mb. These genome sequences provide essential resources for future studies of conservation genetics, population genetics, speciation, and behavioral ecology in this charismatic social insect.

A genome assembly for the Chryxus Arctic (Oeneis chryxus), the highest butterfly in North America.

We describe a highly contiguous and complete diploid genome assembly for the Chryxus Arctic, Oeneis chryxus (E. Doubleday, [1849]), a butterfly species complex spanning much of northern and western North America. One subspecies, the Ivallda Arctic (O. c. ivallda), is endemic to California's Sierra Nevada and of particular biogeographic interest and conservation concern. Extreme alpine habitats occupied by this subspecies include the summit of Mt. Whitney, California, representing the highest elevation butterfly population in North America. The assembly presented here consists of two haplotypes, 738.92 and 770.85 Mb in length, with contig N50 values of 10.49 and 10.13 Mb, scaffold N50 values of 25.35 and 25.69 Mb, scaffold L50 values of 13 and 14, and BUSCO completeness scores of 96.5 and 98.3%, respectively. More than 97% of the assembly is organized into 29 scaffolds, which likely represent whole chromosomes. This assembly is the first major genomic resource for Oeneis, providing a foundational reference for future genomic studies on the taxonomy, evolutionary history, and conservation of the genus. As part of the California Conservation Genomics Project, we will use this assembly in conjunction with short-read resequencing to resolve patterns of evolutionary differentiation, adaptive genomic variation, and gene flow among remaining O. c. ivallda populations. These data can and will be used to inform the subspecies' conservation as warming climatic conditions continue to lead to the loss and fragmentation of alpine habitats. We also provide genome assemblies for the O. chryxus mitochondrion and a Wolbachia endosymbiont.

Per- and polyfluoroalkyl substances (PFAS) in drinking water in Southeast Los Angeles: Industrial legacy and environmental justice.

Per- and polyfluoroalkyl substances (PFAS) are persistent chemicals of increasing concern to human health. PFAS contamination in water systems has been linked to a variety of sources including hydrocarbon fire suppression activities, industrial and military land uses, agricultural applications of biosolids, and consumer products. To assess PFAS in California tap water, we collected 60 water samples from inside homes in four different geographic regions, both urban and rural. We selected mostly small water systems with known history of industrial chemical or pesticide contamination and that served socioeconomically disadvantaged communities. Thirty percent of the tap water samples (18) had a detection of at least one of the 32 targeted PFAS and most detections (89 %) occurred in heavily industrialized Southeast Los Angeles (SELA). The residents of SELA are predominately Latino and low-income. Concentrations of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) ranged from 6.8 to 13.6 ng/L and 9.4-17.8 ng/L, respectively in SELA and were higher than State (PFOA: 0.007 ng/L; PFOS: 1.0 ng/L) and national health-based goals (zero). To look for geographic patterns, we mapped potential sources of PFAS contamination, such as chrome plating facilities, airports, landfills, and refineries, located near the SELA water systems; consistent with the multiple potential sources in the area, no clear spatial associations were observed. The results indicate the importance of systematic testing of PFAS in tap water, continued development of PFAS regulatory standards and advisories for a greater number of compounds, improved drinking-water treatments to mitigate potential health threats to communities, especially in socioeconomically disadvantaged and industrialized areas.

Defining long COVID using a population-based SARS-CoV-2 survey in California.

BACKGROUND: More than four years after the start of the COVID-19 pandemic, understanding of SARS-CoV-2 burden and post-acute sequela of COVID (PASC), or long COVID, continues to evolve. However, prevalence estimates are disparate and uncertain. Leveraging survey responses from a large serosurveillance study, we assess prevalence estimates using five different long COVID definitions among California residents. METHODS: The California Department of Public Health (CDPH) conducted a cross-sectional survey that included questions about acute COVID-19 infection and recovery. A random selection of California households was invited to participate in a survey that included demographic information, clinical symptoms, and COVID-19 vaccination history. We assessed prevalence and predictors of long COVID among those previously testing positive for SARS-CoV-2 across different definitions using logistic regression. FINDINGS: A total of 2883 participants were included in this analysis; the majority identified as female (62.5 %), and the median age was 39 years (interquartile range: 17-55 years). We found a significant difference in long COVID prevalence across definitions with the highest prevalence observed when participants were asked about incomplete recovery (20.9 %, 95 % confidence interval [CI]: 19.4-22.5) and the lowest prevalence was associated with severe long COVID affecting an estimated 4.9 % (95 % CI 4.1-5.7) of the participant population. Individuals that completed the primary vaccination series had significantly lower prevalence of long COVID compared to those that did not receive COVID vaccination. INTERPRETATION: There were significant differences in the estimated prevalence of long COVID across different definitions. People who experience a severe initial COVID-19 infection should be considered at a higher probability for developing long COVID. FUNDING: Centers for Disease Control and Prevention - Epidemiology and Laboratory Capacity.

Factors Associated with Patient Engagement in a Health and Social Needs Case Management Program.

INTRODUCTION: Many patients offered case management services to address their health and social needs choose not to engage. Factors that drive engagement remain unclear. We sought to understand patient characteristics associated with engagement in a social needs case management program and variability by case manager. METHODS: Between August 2017 and February 2021, 43,347 Medicaid beneficiaries with an elevated risk of hospital or emergency department use were offered case management in Contra Costa County, California. Results were analyzed in 2022 using descriptive statistics and multilevel logistic regression models to examine 1) associations between patient engagement and patient characteristics and 2) variation in engagement attributable to case managers. Engagement was defined as responding to case manager outreach and documentation of at least 1 topic to mutually address. A sensitivity analysis was performed by stratifying the pre-COVID-19 and COVID-19 cohorts. RESULTS: A total of 16,811 (39%) of eligible patients engaged. Adjusted analyses indicate associations between higher patient engagement and female gender, age 40 and over, Black/African American race, Hispanic/Latino ethnicity, history of homelessness, and a medical history of certain chronic conditions and depressive disorder. The intraclass correlation coefficient indicates that 6% of the variation in engagement was explained at the case manager level. CONCLUSIONS: Medicaid patients with a history of housing instability and specific medical conditions were more likely to enroll in case management services, consistent with prior evidence that patients with greater need are more receptive to assistance. Case managers accounted for a small percentage of variation in patient engagement.

Cross-Sectional Study Assessing Management Practices and Udder Health in California Sheep Flocks and Seroprevalence of Small Ruminant Lentivirus.

(1) Background: Information is lacking on small ruminant lentivirus (SRLV) status, prevalence, risk factors, and control measures for mastitis in California ewes. The goal of this survey was to outline characteristics of the sheep industry in California related to udder health and mastitis management. (2) Methods: An online survey consisting of 48 questions was completed by respondents between April 2022 and February 2023. Descriptive analysis and chi-squared tests were conducted to evaluate associations between variables. A multiple correspondence analysis (MCA) of general management practices, udder health management, and flock demographics was performed to assess clustering. A subset of respondents (20) participated in SRLV serology testing. (3) Results: Seventy-one completed surveys were submitted. The MCA showed two clusters. Larger flock sizes, the use of breeding ewes for meat or wool production or contract grazing, and extensive management practices were more closely related to >5% udder abnormalities per lactation and ≥5% orphan lambs. The flock-level seroprevalence of SRLV was 75% (15/20), and ewe-level seroprevalence was 14.1% (183/1106). (4) Conclusions: The results of this study highlight areas that need further research, such as exploring differences in mastitis and SRLV incidences among management systems, the efficacy of mastitis treatments, and education on critical timepoints for mastitis diagnosis and control.

Upwelling Enhances Mercury Particle Scavenging in the California Current System.

Coastal upwelling supplies nutrients supporting primary production while also adding the toxic trace metal mercury (Hg) to the mixed layer of the ocean. This could be a concern for human and environmental health if it results in the enhanced bioaccumulation of monomethylmercury (MMHg). Here, we explore how upwelling influences Hg cycling in the California Current System (CCS) biome through particle scavenging and sea-air exchange. We collected suspended and sinking particle samples from a coastal upwelled water parcel and an offshore non-upwelled water parcel and observed higher total particulate Hg and sinking flux in the upwelling region compared to open ocean. To further investigate the full dynamics of Hg cycling, we modeled Hg inventories and fluxes in the upper ocean under upwelling and non-upwelling scenarios. The model simulations confirmed and quantified that upwelling enhances sinking fluxes of Hg by 41% through elevated primary production. Such an enhanced sinking flux of Hg is biogeochemically important to understand in upwelling regions, as it increases the delivery of Hg to the deep ocean where net conversion to MMHg may take place.

Emergence of Recombinant SARS-CoV-2 Variants in California from 2020 to 2022.

The detection, characterization, and monitoring of SARS-CoV-2 recombinant variants constitute a challenge for public health authorities worldwide. Recombinant variants, composed of two or more SARS-CoV-2 lineages, often have unknown impacts on transmission, immune escape, and virulence in the early stages of emergence. We examined 4213 SARS-CoV-2 recombinant SARS-CoV-2 genomes collected between 2020 and 2022 in California to describe regional and statewide trends in prevalence. Many of these recombinant genomes, such as those belonging to the XZ lineage or novel recombinant lineages, likely originated within the state of California. We discuss the challenges and limitations surrounding Pango lineage assignments, the use of publicly available sequence data, and adequate sample sizes for epidemiologic analyses. Although these challenges will continue as SARS-CoV-2 sequencing volumes decrease globally, this study enhances our understanding of SARS-CoV-2 recombinant genomes to date while providing a foundation for future insights into emerging recombinant lineages.

Amelioration of fat clay treated with CNS and cohesionless soils.

The present study evaluates the amelioration of fat clay by blending it with cohesive non-swelling soil (CNS) and cohesionless silty sandy soil (Kassu). The fat clay sample with a liquid limit (LL) of 50 and a plasticity index (PI) of 26 was collected from Narowal, while CNS and Kassu samples were procured from Lahore's outskirts. Geotechnical tests on the virgin soil indicated its unsuitability for construction. Laboratory tests, including modified Proctor compaction, unconfined compression, California bearing ratio (CBR), and one-dimensional consolidation, were performed on samples blended with 0-35% CNS or Kassu in 5% intervals. The LL and PI of fat clay decreased significantly with the addition of 35% CNS (LL: 50-32%, PI: 24 to 13) and Kassu (LL: 50-29%, PI: 24-12). The CBR value increased from 4 to 7%, making the blended soil suitable for subgrade use. Unconfined compression tests showed a strength increase from 102 to 185 kPa with 35% CNS and up to 140 kPa with 25% Kassu. Compaction tests revealed improved maximum dry unit weight and reduced optimum moisture content. Swell potential decreased from 4 to 1.2 and 0.26% with CNS and Kassu additions. Regression models predict swell pressure and ultimate swell potential. The study concludes that blending fat clay with CNS and Kassu significantly improves its geotechnical properties, with CNS being more effective in controlling swell characteristics.

Geospatial Point-of-Care Testing Strategies for COVID-19 Resilience in Resource-Poor Settings: Rural Cambodia Field Study.

BACKGROUND: Point-of-care testing (POCT) generates intrinsically fast, inherently spatial, and immediately actionable results. Lessons learned in rural Cambodia and California create a framework for planning and mobilizing POCT with telehealth interventions. Timely diagnosis can help communities assess the spread of highly infectious diseases, mitigate outbreaks, and manage risks. OBJECTIVE: The aims of this study were to identify the need for POCT in Cambodian border provinces during peak COVID-19 outbreaks and to quantify geospatial gaps in access to diagnostics during community lockdowns. METHODS: Data sources comprised focus groups, interactive learners, webinar participants, online contacts, academic experts, public health experts, and officials who determined diagnostic needs and priorities in rural Cambodia during peak COVID-19 outbreaks. We analyzed geographic distances and transit times to testing in border provinces and assessed a high-risk province, Banteay Meanchey, where people crossed borders daily leading to disease spread. We strategized access to rapid antigen testing and molecular diagnostics in the aforementioned province and applied mobile-testing experience among the impacted population. RESULTS: COVID-19 outbreaks were difficult to manage in rural and isolated areas where diagnostics were insufficient to meet needs. The median transit time from border provinces (n=17) to testing sites was 73 (range 1-494) minutes, and in the high-risk Banteay Meanchey Province (n=9 districts), this transit time was 90 (range 10-150) minutes. Within border provinces, maximum versus minimum distances and access times for testing differed significantly (P<.001). Pareto plots revealed geospatial gaps in access to testing for people who are not centrally located. At the time of epidemic peaks in Southeast Asia, mathematical analyses showed that only one available rapid antigen test met the World Health Organization requirement of sensitivity >80%. We observed that in rural Solano and Yolo counties, California, vending machines and public libraries dispensing free COVID-19 test kits 24-7 improved public access to diagnostics. Mobile-testing vans equipped with COVID-19 antigen, reverse transcription polymerase chain reaction, and multiplex influenza A/B testing proved useful for differential diagnosis, public awareness, travel certifications, and telehealth treatment. CONCLUSIONS: Rural diagnostic portals implemented in California demonstrated a feasible public health strategy for Cambodia. Automated dispensers and mobile POCT can respond to COVID-19 case surges and enhance preparedness. Point-of-need planning can enhance resilience and assure spatial justice. Public health assets should include higher-quality, lower-cost, readily accessible, and user-friendly POCT, such as self-testing for diagnosis, home molecular tests, distributed border detection for surveillance, and mobile diagnostics vans for quick telehealth treatment. High-risk settings will benefit from the synthesis of geospatially optimized POCT, automated 24-7 test access, and timely diagnosis of asymptomatic and symptomatic patients at points of need now, during new outbreaks, and in future pandemics.

De novo genome assembly of a Geomyid rodent, Botta's pocket gopher (Thomomys bottae bottae).

Botta's pocket gopher (Thomomys bottae) is a common and widespread subterranean rodent of the North American west. The species has been of long interest to evolutionary biologists due to the phenotypic diversity across its range and unusual levels of variation in chromosome number and composition. Here, we present a high-quality reference genome from a male T. b. bottae individual captured in the San Francisco Bay Area. The assembly is comprised of 2,792 scaffolds, with a scaffold N50 value of 23.6 Mb and a BUSCO score of 91.0%. This genome helps fill a significant taxonomic sampling gap in rodent genome resources. With this reference genome, we envision new opportunities to investigate questions regarding the genomics of adaptation to the belowground niche. Further, we can begin to explore the impact of associated life history traits, such as limited dispersal and low population connectivity, on intraspecific genetic and phenotypic variation, genome evolution, speciation, and phylogenetic relationships across the Geomyoidea.

The Effect of Rituximab on the Cognitive Function of Patients with Relapsing-Remitting Multiple Sclerosis.

PURPOSE: Cognitive impairment can begin in the early stages of multiple sclerosis (MS). No medicine has been approved for treating cognitive impairment in MS patients. There is a lack of data on the role of rituximab in managing cognitive impairment in MS patients. Using minimal assessment of cognitive function in MS (MACFIMS), this study aims to investigate the effect of rituximab on the cognitive status of relapsing-remitting MS (RRMS) patients. METHODS: In this pre-post interventional trial, 28 eligible RRMS patients participated. They were administered rituximab for a year. Cognitive tests (MACFIMS), MS neuropsychological questionnaire (MSNQ), and Beck depression inventory-fast screen (BDI-FS) scores were evaluated at baseline, six, and 12 months following rituximab administration. FINDINGS: Eighteen participants with a mean age of 40.5 ± 12.91, 7 men, completed all three follow-ups. There was no statistically significant change in BDI-FS, MSNQ, Paced Auditory Serial Addition Test (P: 0.743), Symbol Digit Modalities Test (P: 0.711), Brief Visual Memory Test (BVMT) (P: 0.426), learning BVMT (P: 0.268), and delayed recall BVMT (P: 0.394) scores. However, the California Verbal Learning Test (CVLT), CVLT learning, and Controlled Oral Word Association Test scores significantly improved by 45.2% (P < 0.001), 12.3% (P: 0.013), and 26.7% (P: 0.011), respectively, 6-month follow-up rituximab treatment. There was a significant improvement in CVLT (+55.7%, P < 0.001), CVLT learning (+15.9%, P: 0.011), and delayed recall CVLT (+28%, P: 0.022) scores 12-month follow-up rituximab treatment. IMPLICATIONS: Rituximab prevents cognitive deterioration and improves some cognitive functions. Further investigations with a larger sample size, longer follow-ups, and inclusion of a placebo or another treatment arm are recommended.

Accelerating microplastic contamination in 210Pb dated sediment cores from an urbanized coastal lagoon (NW Mexico) since the 1990s.

The ubiquity of microplastics (MP) across all ecosystems raises concerns about their potential harm to the environment and living organisms. Sediments are a MP sink, reflecting long-term accumulation and historical anthropogenic impacts. Three 210Pb-dated sediment cores were used to understand the temporal variations of MP abundances (particles kg-1) and fluxes (particles m-2 year-1) within the past century in Estero de Urías Lagoon, an urbanized coastal lagoon in the Mexican Pacific. MP particles, extracted from sediments by density separation (saturated NaCl solution) were counted using a stereomicroscope, under visible and ultraviolet light on Nile red (NR) stained filters. The polymer composition was determined in ∼10 % of the suspected MP particles using Fourier Transform Infrared spectrometry. Fibers (66 to 89 % of the total particles) predominated over fragments (11 to 34 %). Before 1950, no MP particles were detected. Polyethylene terephthalate (PET) was the prevalent synthetic polymer (up to 50 % of the particles), while semisynthetic cellulosic fibers were predominant, underscoring the broader scope of anthropogenic contamination. Suspected MP abundances (NR stained filters) were highest in the core collected at the innermost area, which was attributed to the lagoon's hydrodynamics, since current velocities decrease from the proximal to the distal area to the sea. From the regression between MP fluxes and time elapsed since sediments deposited, the cores showed consistent accelerated increases of MP burial since mid-20th century, most likely because of the increasing availability of plastic products and population growth, with the consequent increment in plastic waste and wastewater releases. Our findings emphasize the growing MP pollution challenges at EUL, which may directly impact subsistence fishing and shrimp aquaculture activities, threatening local livelihoods and food sources; and also highlight the need for improved waste management and pollution control strategies in rapidly industrializing regions, to protect both aquatic ecosystems and human populations dependent on fishing products.

First Genomic Evidence of California Hare Coltivirus from Natural Populations of Ixodes persulcatus Ticks in Northeast China.

Background: California hare coltivirus (CHCV) was isolated in California in 1976 from a hare. Despite its long history, it remained unclear whether CHCV was exclusively distributed in California with limited host ranges. Main body: By next-generation sequencing (NGS), we obtained a complete sequence of CHCV from Ixodes persulcatus collected in 2019 in northeast China. An expanded epidemiological investigation was subsequently performed on ticks belonging to four species (Ix. persulcatus, Haemaphysalis concinna, Devmacentor silvarum, Haemaphysalis longicornis) collected in northeastern China by applying CHCV-specific RT-PCR and sequencing. CHCV RNA-positive results were found in 1.56% of the tick samples. Positive ticks were obtained in three of four sampled locations, with the highest rate observed in Inner Mongolia (2.69%), followed by Heilongjiang (1.94%) and Jilin provinces (0.55%). All positive results were derived from Ix. persulcatus ticks (2.33%), while no positive detection was found in the other tick species, even at the same location. Sequence analysis revealed that the current CHCV showed a high genetic identity (>80% amino acid identity) with the previously reported CHCV in all segments except segment seven (64.59% amino acid identity). Phylogenetic analysis based on RNA-dependent RNA polymerase (RdRp) amino acid sequences demonstrated that both the current and previously reported CHCV strains were grouped phylogenetically into the genus Coltivirus. Both CHCV strains formed a distinct clade, clustering with three human pathogenic coltiviruses (Colorado tick fever virus, Salmon River virus, and Eyach virus), and were distant from the other coltiviruses. Conclusions: We report the identification and characterization of CHCV for the first time in Ix. persulcatus ticks, expanding the currently known geographic scope, host, and genetic heterogeneity in CHCV.

A genome assembly of the American black bear, Ursus americanus, from California.

The American black bear, Ursus americanus, is a widespread and ecologically important species in North America. In California, the black bear plays an important role in a variety of ecosystems and serves as an important species for recreational hunting. While research suggests that the populations in California are currently healthy, continued monitoring is critical, with genomic analyses providing an important surveillance tool. Here we report a high-quality, near chromosome-level genome assembly from a U. americanus sample from California. The primary assembly has a total length of 2.5 Gb contained in 316 scaffolds, a contig N50 of 58.9 Mb, a scaffold N50 of 67.6 Mb, and a BUSCO completeness score of 96%. This U. americanus genome assembly will provide an important resource for the targeted management of black bear populations in California, with the goal of achieving an appropriate balance between the recreational value of black bears and the maintenance of viable populations. The high quality of this genome assembly will also make it a valuable resource for comparative genomic analyses among black bear populations and among bear species.

Birth defects among offspring of California firefighters, 2007-2019.

PURPOSE: Limited research examines birth defects from maternal or paternal firefighting exposure. This study aims to assess if maternal or paternal occupational exposure to firefighting during periconception is associated with offspring birth defects. METHODS: Data from California birth certificates (2007-2019) were linked to maternal / offspring hospitalization records. Occupation during the periconceptional period was categorized from vital statistics as the following: paternal non-firefighting (n = 4,135,849), paternal firefighting (n = 22,732), maternal non-firefighting (n = 3,332,255) and maternal firefighting (n = 502). Birth defects were identified using ICD codes, grouped by anatomical regions. Adjusted odds ratios were estimated, and sensitivity analyses explored police officer reference groups and detailed birth defect categories. RESULTS: Offspring of paternal firefighters had lower odds of circulatory defects (aOR = 0.9, 95% CI 0.8, 1.0), oral clefts (aOR = 0.6, 95% CI 0.4, 0.8) and respiratory defects (0.7, 95% CI 0.6, 0.9) compared to paternal non-firefighters. Associations between maternal firefighting and offspring birth defects were imprecise. Substituting police officers as the reference group attenuated findings. CONCLUSIONS: Offspring of paternal firefighters may have similar or slightly lower birth defect odds compared to offspring of non-firefighters. Limited data was available for assessing maternal firefighting outcomes. Future studies should prioritize studies using occupational exposure matrices to limit misclassification of exposure.

California dreaming: Why environmental justice is integral to the success of climate change policy.

In the realm of climate policy, issues of environmental justice (EJ) are often treated as second-order affairs compared to overarching sustainability goals. We argue that EJ is in fact critical to successfully addressing our national and global climate challenges; indeed, centering equity amplifies the voices of the diverse constituencies most impacted by climate change and that are needed to build successful coalitions that shape and advance climate change policy. We illustrate this perspective by highlighting the experience of California and the contentious processes by which EJ became integrated into the state's climate action efforts. We examine the achievements and shortcomings of California's commitment to climate justice and discuss how lessons from the Golden State are influencing the evolution of current federal climate change policy.

Cultivating climate resilience in California agriculture: Adaptations to an increasingly volatile water future.

California agriculture will undergo significant transformations over the next few decades in response to climate extremes, environmental regulation and policy encouraging environmental justice, and economic pressures that have long driven agricultural changes. With several local climates suited to a variety of crops, periodically abundant nearby precipitation, and public investments that facilitated abundant low-priced irrigation water, California hosts one of the most diverse and productive agroecosystems in the world. California farms supply nearly half of the high-nutrient fruit, tree nut, and vegetable production in the United States. Climate change impacts on productivity and profitability of California agriculture are increasing and forebode problems for standard agricultural practices, especially water use norms. We highlight many challenges California agriculture confronts under climate change through the direct and indirect impacts on the biophysical conditions and ecosystem services that drive adaptations in farm practices and water accessibility and availability. In the face of clear conflicts among competing interests, we consider ongoing and potential sustainable and equitable solutions, with particular attention to how technology and policy can facilitate progress.

The importance of geography in forecasting future fire patterns under climate change.

An increasing amount of California's landscape has burned in wildfires in recent decades, in conjunction with increasing temperatures and vapor pressure deficit due to climate change. As the wildland-urban interface expands, more people are exposed to and harmed by these extensive wildfires, which are also eroding the resilience of terrestrial ecosystems. With future wildfire activity expected to increase, there is an urgent demand for solutions that sustain healthy ecosystems and wildfire-resilient human communities. Those who manage disaster response, landscapes, and biodiversity rely on mapped projections of how fire activity may respond to climate change and other human factors. California wildfire is complex, however, and climate-fire relationships vary across the state. Given known geographical variability in drivers of fire activity, we asked whether the geographical extent of fire models used to create these projections may alter the interpretation of predictions. We compared models of fire occurrence spanning the entire state of California to models developed for individual ecoregions and then projected end-of-century future fire patterns under climate change scenarios. We trained a Maximum Entropy model with fire records and hydroclimatological variables from recent decades (1981 to 2010) as well as topographic and human infrastructure predictors. Results showed substantial variation in predictors of fire probability and mapped future projections of fire depending upon geographical extents of model boundaries. Only the ecoregion models, accounting for the unique patterns of vegetation, climate, and human infrastructure, projected an increase in fire in most forested regions of the state, congruent with predictions from other studies.

Climate change and California's terrestrial biodiversity.

In this review and synthesis, we argue that California is an important test case for the nation and world because terrestrial biodiversity is very high, present and anticipated threats to biodiversity from climate change and other interacting stressors are severe, and innovative approaches to protecting biodiversity in the context of climate change are being developed and tested. We first review salient dimensions of California's terrestrial physical, biological, and human diversity. Next, we examine four facets of the threat to their sustainability of these dimensions posed by climate change: direct impacts, illustrated by a new analysis of shifting diversity hotspots for plants; interactive effects involving invasive species, land-use change, and other stressors; the impacts of changing fire regimes; and the impacts of land-based renewable energy development. We examine recent policy responses in each of these areas, representing attempts to better protect biodiversity while advancing climate adaptation and mitigation. We conclude that California's ambitious 30 × 30 Initiative and its efforts to harmonize biodiversity conservation with renewable energy development are important areas of progress. Adapting traditional suppression-oriented fire policies to the reality of new fire regimes is an area in which much progress remains to be made.