SEARCH · Search USGS

Results for “One Health Cases”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

USGS2025

The crystalline silica respiratory hazard from rhyolitic lava dome eruptions in New Zealand's Taupo Volcanic Zone: A case study from the 1315 CE Kaharoa eruption

The rhyolitic Kaharoa 1315 CE eruption was a complex, long-lived event from Tarawera volcano, New Zealand. Explosive phases were followed by around 5 years of lava dome extrusion and collapse which produced block-and-ash flows (BAF). Lava domes generate crystalline silica in the form of cristobalite, and rhyolitic magmas often contain quartz phenocrysts. Fine-grained ash containing crystalline silica can be formed through dome collapses or explosions, generating a respiratory health hazard for communities affected by ashfall. The aims of this study are to: i) determine whether the Kaharoa eruption dome-forming phase generated substantial quantities of crystalline silica and, therefore, to determine the potential for future dome-forming eruptions of Tarawera to do the same; ii) consider the potential hazard of the crystalline silica by studying the crystal habit and chemistry compared to other lava domes, globally; and iii) assess the particle size and crystalline silica content of the Kaharoa ash, to inform a respiratory hazard assessment. Five co-BAF ash samples and one co-ignimbrite (explosive) ash sample from the Kaharoa pyroclastic deposits were analysed for health-pertinent factors: particle size distribution and crystalline silica content. Eight dome-rock samples were collected from the dome complex and associated BAF deposits and groundmass texture (especially forms of crystalline silica) and quantity of crystalline silica were assessed. Cristobalite was present in the 4 ash samples analysed by X-ray diffraction (XRD; 1.3–3.7 wt%) as was quartz (5.7–12.5 wt%). For the 4 dome samples analysed by XRD, all samples contained quartz (4.1–10.4 wt%) and two contained significant quantities of cristobalite (24.7 and 27.3 wt%). Of the two dome samples with minimal cristobalite (visible as individual vapour-phase crystals by SEM but not quantifiable by XRD), one was from the non-devitrified dome carapace and the other was from the compacted interior but had not undergone devitrification. The two dome samples with substantial cristobalite were from dome interiors and were highly devitrified, with well-developed spherulitic textures. Using energy-dispersive X-ray spectroscopy, cristobalite in all samples contained minor aluminium, as has been seen for volcanic cristobalite from other lava domes, which may ameliorate its toxicity. By laser diffraction, the quantities of ash in the health pertinent size fractions varied, with a range of 1.3–8.1 vol% for particles of <4 μm diameter and 1.7–15.6 vol% for particles of <10 μm diameter, which is lower than measured in ash from large-scale dome collapse events at other volcanoes. The findings suggest a potential for substantial crystalline silica to be formed in future Kaharoa-style eruptions, but that cristobalite generation is site-specific, depending on location within the dome and whether the dome remains sufficiently hot for spherulite formation and glass devitrification. Respiratory hazard will therefore vary depending on the collapse of (or explosions through) individual lobes – although all lava is expected to contain quartz phenocrysts – as well as the size and energy of those collapses, which will influence particle size and quantity of ash generated and dispersed.

Taupo Volcanic Zone↗

USGS2010

Real-time seismic monitoring of structures: Data handling and case studies

Within the last decade, advances in the acquisition, processing and transmission of data from real-time seismic monitoring systems has contributed to the growth in the number structures instrumented with such systems. An equally important factor for such growth can be attributed to the demands by stakeholders to find rapid answers to important questions related to the functionality (or “state of health”) of structures during and immediately following a seismic event. Hence, rapid and accurate assessment of the damage condition or performance of a building or a lifeline structure is of paramount importance to stakeholders, including owners, leasers, permanent and/or temporary occupants, users of infrastructures, city officials and rescue teams that are concerned with safety of those in the building, and those that may be affected in nearby buildings and infrastructures. In earlier papers, we described how observed data from sensors deployed in structures can be configured to establish seismic health monitoring of structures. In these configurations, drift ratios are the main parametric indicator of damage condition of a building. The process described for buildings can be applied directly for bridges as well. For bridges, the term, “drift ratio” is not generally used; however, relative displacements of critical elements of a bridge can be construed as such. While real-time data from structural arrays indicate that these methods are reliable and provide requisite information for owners and other parties to make informed decisions and to choose among pre-defined actions following significant events, there are several issues related to data ownership, transmission and archiving. This paper examines the real-time seismic monitoring systems deployed mainly in the United States, with particular attention to data issues – handling, dissemination, storage, and archiving. In most cases, due to the numerous channels involved, the deployments in each one of the real-time structures can be considered to be an individual array. Two detailed cases are described that demonstrate the variability in data ownership and dissemination.

Book chapter↗

USGS2015

Linking climate change and health outcomes: Examining the relationship between temperature, precipitation and birth weight in Africa

This paper examined the relationship between birth weight, precipitation, and temperature in 19 African countries. We matched recorded birth weights from Demographic and Health Surveys covering 1986 through 2010 with gridded monthly precipitation and temperature data derived from satellite and ground-based weather stations. Observed weather patterns during various stages of pregnancy were also used to examine the effect of temperature and precipitation on birth weight outcomes. In our empirical model we allowed the effect of weather factors to vary by the dominant food production strategy (livelihood zone) in a given region as well as by household wealth, mother's education and birth season. This allowed us to determine if certain populations are more or less vulnerable to unexpected weather changes after adjusting for known covariates. Finally we measured effect size by observing differences in birth weight outcomes in women who have one low birth weight experience and at least one healthy birth weight baby. The results indicated that climate does indeed impact birth weight and at a level comparable, in some cases, to the impact of increasing women's education or household electricity status.

Global Environmental Change↗

USGS2023

Assessment of resource potential from mine tailings using geostatistical modeling for compositions: A methodology and application to Katherine Mine site, Arizona, USA

The mining industry, in most cases, targets a specific valuable commodity that is present in small quantities within large volumes of extracted material. After milling and processing, most of the extracted material and the effluents are stored as waste (tailings) in impoundments, such as dams or waste dumps, or are backfilled into underground mines. In time, tailing materials may become an issue of environmental and health concern due to the hazardous elements, ions, and oxides contained within the waste material. In addition, handling and storage of such waste in dams may pose the risk of dam failure with catastrophic consequences to nature and nearby communities. On the other hand, tailings may offer potential as secondary sources of critical elements (CEs), including rare earth elements (REEs), which may have been overlooked during primary production and processing. Therefore, treating mine tailings as a resource has economic and environmental benefits by reducing the waste from new and historical mine sites through remining. One of the critical steps for taking advantage of these benefits is to spatially quantify the resources and the pollutants, which require the application of adequate data analysis and modeling methods, often to compositional geochemical data. Utilizing adequate methods is especially important for correctly quantifying resource potential, as the quantities will often be at low concentrations. This work presents quantification of resource potential (Au, Ag, Cu, Zn, Pb) and elements of environmental concern (Hg and As) from the tailings of a historic mine site, Katherine Mine, AZ, USA. Data reported by the U.S. Bureau of Mines (USBM) after extensive field campaigns in the 1990s, including sampling from tailing impoundment and surrounding areas for geochemical characterization and geophysical surveys, were used. First, compositional data (CoDa) analysis was employed to explore associations of sampling locations, geochemical parts, and the clustering of samples. Next, sequential Gaussian simulation (SGSIM) was applied to samples that showed a genetic link to tailing material after isometric log-ratio transformation (ilr) and mix/max autocorrelation factor (MAF) transformation for spatial modeling and uncertainty evaluation. Geostatistical results revealed spatial variability of concentrations within the tailing area. Uncertainty evaluation based on realizations indicated that Cu (14.27–20.01 t), Zn (44.23–76.23 t), and Pb (22.56–38.28 t) are the most abundant elements within a 5 %–95 % interval, followed by Ag and Au (~5.3 and 0.18 t, at 50th percentile), respectively. Of the elements of health concern, As was found to be ~4.8 t (50th percentile) in the tailing area. The work also showed that ~0.51 t As, 0.005 t Hg, 0.020 t of Au, and 0.62 t of Ag were carried to Lake Mohave by an ephemeral stream called Katherine Wash, which transects the tailings.

Arizona↗

USGS2016

Disparity between state fish consumption advisory systems for methylmercury and US Environmental Protection Agency recommendations: A case study of the South Central United States

Fish consumption advisories are used to inform citizens in the United States about noncommercial game fish with hazardous levels of methylmercury (MeHg). The US Environmental Protection Agency (USEPA) suggests issuing a fish consumption advisory when concentrations of MeHg in fish exceed a human health screening value of 300 ng/g. However, states have authority to develop their own systems for issuing fish consumption advisories for MeHg. Five states in the south central United States (Arkansas, Louisiana, Mississippi, Oklahoma, and Texas) issue advisories for the general human population when concentrations of MeHg exceed 700 ng/g to 1000 ng/g. The objective of the present study was to estimate the increase in fish consumption advisories that would occur if these states followed USEPA recommendations. The authors used the National Descriptive Model of Mercury in Fish to estimate the mercury concentrations in 5 size categories of largemouth bass–equivalent fish at 766 lentic and lotic sites within the 5 states. The authors found that states in this region have not issued site‐specific fish consumption advisories for most of the water bodies that would have such advisories if USEPA recommendations were followed. One outcome of the present study may be to stimulate discussion between scientists and policy makers at the federal and state levels about appropriate screening values to protect the public from the health hazards of consuming MeHg‐contaminated game fish.

Arkansas, Louisiana, Mississippi, Oklahoma, Texas↗

USGS2016

Biochemical and clinical responses of Common Eiders to implanted satellite transmitters

Implanted biologging devices, such as satellite-linked platform transmitter terminals (PTTs), have been used widely to delineate populations and identify movement patterns of sea ducks. Although in some cases these ecological studies could reveal transmitter effects on behavior and mortality, experiments conducted under controlled conditions can provide valuable information to understand the influence of implanted tags on health and physiology. We report the clinical, mass, biochemical, and histological responses of captive Common Eiders ( Somateria mollissima ) implanted with PTTs with percutaneous antennas. We trained 6 individuals to dive 4.9 m for their food, allowed them to acclimate to this dive depth, and implanted them with PTTs. We collected data before surgery to establish baselines, and for 3.5 mo after surgery. The first feeding dive took place 22 hr after surgery, with 5 of 6 birds diving to the bottom within 35 hr of surgery. Plumage waterproofing around surgical sites was reduced ≤21 days after surgery. Mass; albumin; albumin:globulin ratio; aspartate aminotransferase; β 1 -, β 2 -, and γ-globulins; creatine kinase; fecal glucocorticoid metabolites; heterophil:lymphocyte ratio; and packed cell volume changed from baseline on one or more of the postsurgery sampling dates, and some changes were still evident 3.5 mo after surgery. Our findings show that Common Eiders physiologically responded for up to 3.5 mo after surgical implantation of a PTT, with the greatest response occurring within the first few weeks of implantation. These responses support the need for postsurgery censor periods for satellite telemetry data and should be considered when designing studies and analyzing information from PTTs in sea ducks.

The Condor↗

USGS2017

Overview of avian toxicity studies for the Deepwater Horizon Natural Resource Damage Assessment

The Oil Pollution Act of 1990 establishes liability for injuries to natural resources because of the release or threat of release of oil. Assessment of injury to natural resources resulting from an oil spill and development and implementation of a plan for the restoration, rehabilitation, replacement or acquisition of natural resources to compensate for those injuries is accomplished through the Natural Resource Damage Assessment (NRDA) process. The NRDA process began within a week of the Deepwater Horizon oil spill, which occurred on April 20, 2010. During the spill, more than 8500 dead and impaired birds representing at least 93 avian species were collected. In addition, there were more than 3500 birds observed to be visibly oiled. While information in the literature at the time helped to identify some of the effects of oil on birds, it was not sufficient to fully characterize the nature and extent of the injuries to the thousands of live oiled birds, or to quantify those injuries in terms of effects on bird viability. As a result, the US Fish and Wildlife Service proposed various assessment activities to inform NRDA injury determination and quantification analyses associated with the Deepwater Horizon oil spill, including avian toxicity studies. The goal of these studies was to evaluate the effects of oral exposure to 1–20 ml of artificially weathered Mississippi Canyon 252 oil kg bw -1 day -1 from one to 28 days or one to five applications of oil to 20% of the bird's surface area. It was thought that these exposure levels would not result in immediate or short-term mortality but might result in physiological effects that ultimately could affect avian survival, reproduction and health. These studies included oral dosing studies, an external dosing study, metabolic and flight performance studies and field-based flight studies. Results of these studies indicated changes in hematologic endpoints including formation of Heinz bodies and changes in cell counts. There were also effects on multiple organ systems, cardiac function and oxidative status. External oiling affected flight patterns and time spent during flight tasks indicating that migration may be affected by short-term repeated exposure to oil. Feather damage also resulted in increased heat loss and energetic demands. The papers in this special issue indicate that the combined effects of oil toxicity and feather effects in avian species, even in the case of relatively light oiling, can significantly affect the overall health of birds.

Ecotoxicology and Environmental Safety↗

USGS2020

Emergence of a zoonotic pathogen in a coastal marine sentinel: Capillaria hepatica (syn. Calodium hepaticum)-associated hepatitis in southern sea otters (Enhydra lutris nereis)

Capillaria hepatica is a globally distributed zoonotic nematode parasite that most commonly infects feral and native rats. Soil contact, pica, and living in close proximity to rat populations are risk factors for human infection. Larval nematodes and eggs that were morphologically consistent with C. hepatica were observed microscopically in livers of stranded southern sea otters ( Enhydra lutris nereis ) from California. Large (90–100 × 45–55 μm), barrel-shaped non-embryonated parasite eggs with large polar prominences and a roughened or striated surface, or 105–120 μm diameter larval aphasmid nematode profiles with a prominent stichosome and hypodermal bands were observed in the livers of three otters. The liver of a fourth animal exhibited serpiginous tracts of necrosis, micro-cavitation and pleocellular inflammation, with intralesional linear eosinophilic material that resembled cuticle from degenerating metazoan parasites. Capillaria hepatica -associated hepatitis and capsular adhesions were the cause of death for one otter, and parasite-associated liver lesions were observed in all cases. All infected otters were adult females that stranded from 2006 through 2016 at multiple sites along the central California coast. All cases stranded from December through May; during and soon after peak seasonal precipitation and land-sea runoff in California. This same seasonal pattern has been reported for other land-based parasites infecting southern sea otters. Neither C. hepatica , nor any similar nematodes have been reported from marine mammals, and southern sea otters are not typical hosts for C. hepatica or any other nematode parasites. The most likely route of exposure was via freshwater runoff containing embryonated eggs liberated from predated or decomposing terrestrial hosts, especially rats. Similar to the land-based parasites Toxoplasma gondii and Sarcocystis neurona , C. hepatica eggs may be concentrated and transmitted through filter-feeding marine invertebrates that serve as southern sea otter prey, which may also pose an unrecognized public health risk for people who consume these species.

California↗

USGS2023

A coupled human and natural systems framework to characterize emerging infectious diseases: The case of fibropapillomatosis in marine turtles

Emerging infectious diseases of wildlife have markedly increased in the last few decades. Unsustainable, continuous, and rapid alterations within and between coupled human and natural systems have significantly disrupted wildlife disease dynamics. Direct and indirect anthropogenic effects, such as climate change, pollution, encroachment, urbanization, travel, and trade, can promote outbreaks of infectious diseases in wildlife. We constructed a coupled human and natural systems framework identifying three main wildlife disease risk factors behind these anthropogenic effects: (i) immune suppression, (ii) viral spillover, and (iii) disease propagation. Through complex and convoluted dynamics, each of the anthropogenic effect listed in our framework can lead, to some extent, to one or more of the identified risk factors accelerating disease outbreaks in wildlife. In this review, we present a novel framework to study anthropogenic impacts within coupled human and natural systems that facilitate emergence of infectious disease involving wildlife. We demonstrate the utility of the framework by applying it to Fibropapillomatosis disease of marine turtles. We aim to articulate the intricate and complex nature of anthropogenically-exacerbated wildlife infectious diseases as multifactorial. This paper supports the adoption of a One Health approach and invites the collaboration of multiple disciplines for the achievement of effective and long-lasting conservation and wildlife emerging diseases mitigation outcomes.

Animals↗

USGS2023

Green turtle fibropapillomatosis: Tumor morphology and growth rate in a rehabilitation setting

Fibropapillomatosis (FP) is a neoplastic disease most often found in green turtles ( Chelonia mydas ). Afflicted turtles are burdened with potentially debilitating tumors concentrated externally on the soft tissues, plastron, and eyes and internally on the lungs, kidneys, and the heart. Clinical signs occur at various levels, ranging from mild disease to severe debilitation. Tumors can both progress and regress in affected turtles, with outcomes ranging from death due to the disease to complete regression. Since its official description in the scientific literature in 1938, tumor growth rates have been rarely documented. In addition, FP tumors come in two very different morphologies; yet, to our knowledge, there have been no quantified differences in growth rates between tumor types. FP tumors are often rugose in texture, with a polypoid to papillomatous morphology, and may or may not be pedunculated. In other cases, tumors are smooth, with a skin-like surface texture and little to no papillose structures. In our study, we assessed growth-rate differences between rugose and smooth tumor morphologies in a rehabilitation setting. We measured average biweekly tumor growth over time in green turtles undergoing rehabilitation at the University of Florida Whitney Laboratory Sea Turtle Hospital in St. Augustine, Florida, and compared growth between rugose and smooth tumors. Our results demonstrate that both rugose and smooth tumors follow a similar active growth progression pattern, but rugose tumors grew at significantly faster rates ( p = 0.013) than smooth ones. We also documented regression across several examined tumors, ranging from −0.19% up to −10.8% average biweekly negative growth. Our study offers a first-ever assessment of differential growth between tumor morphologies and an additional diagnostic feature that may lead to a more comprehensive understanding and treatment of the disease. We support the importance of tumor morphological categorization (rugose versus smooth) being documented in future FP hospital- and field-based health assessments.

Veterinary Sciences↗

USGS2014

Status and understanding of groundwater quality in the Klamath Mountains study unit, 2010: California GAMA Priority Basin Project

Groundwater quality in the Klamath Mountains (KLAM) study unit was investigated as part of the Priority Basin Project of the California Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in Del Norte, Humboldt, Shasta, Siskiyou, Tehama, and Trinity Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA Priority Basin Project was designed to provide a spatially unbiased, statistically robust assessment of the quality of untreated (raw) groundwater in the primary aquifer system. The assessment is based on water-quality data and explanatory factors for groundwater samples collected in 2010 by the USGS from 39 sites and on water-quality data from the California Department of Public Health (CDPH) water-quality database. The primary aquifer system was defined by the depth intervals of the wells listed in the CDPH water-quality database for the KLAM study unit. The quality of groundwater in the primary aquifer system may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. This study included two types of assessments: (1) a status assessment , which characterized the status of the current quality of the groundwater resource by using data from samples analyzed for volatile organic compounds, pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements, and (2) an understanding assessment , which evaluated the natural and human factors potentially affecting the groundwater quality. The assessments were intended to characterize the quality of groundwater resources in the primary aquifer system of the KLAM study unit, not the quality of treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentrations divided by the health- or aesthetic-based benchmark concentrations) were used for evaluating groundwater quality for those constituents that have Federal or California regulatory or non-regulatory benchmarks for drinking-water quality. A relative-concentration greater than (>) 1.0 indicates a concentration greater than a benchmark, and a relative-concentration less than or equal to (≤) 1.0 indicates a concentration less than or equal to a benchmark. Relative-concentrations of organic constituents were classified as “high” (relative-concentration > 1.0), “moderate” (0.1 < relative-concentration ≤ 1.0), or “low” (relative-concentration ≤ 0.1). For inorganic constituents, the boundary between low and moderate relative-concentration was set at 0.5. Aquifer-scale proportion was used in the status assessment as the primary metric for evaluating regional-scale groundwater quality. High aquifer-scale proportion is defined as the percentage of the area of the primary aquifer system with a relative-concentration greater than 1.0 for a particular constituent or class of constituents; percentage is based on an areal rather than a volumetric basis. Moderate and low aquifer-scale proportions were defined as the percentages of the primary aquifer system with moderate and low relative-concentrations, respectively. The KLAM study unit includes more than 8,800 square miles (mi 2 ), but only those areas near the sampling sites, about 920 mi 2 , are included in the areal assessment of the study unit. Two statistical approaches—grid-based and spatially weighted—were used to evaluate aquifer-scale proportions for individual constituents and classes of constituents. To confirm this methodology, 90 percent confidence intervals were calculated for the grid-based high aquifer-scale proportions and were compared to the spatially weighted results, which were found to be within these confidence intervals in all cases. Grid-based results were selected for use in the status assessment unless, as was observed in a few cases, a grid-based result was zero and the spatially weighted result was not zero, in which case, the spatially weighted result was used. The status assessment showed that inorganic constituents with human-health benchmarks were detected at high relative-concentrations in 2.6 percent of the primary aquifer system and at moderate relative-concentrations in 10 percent of the system. The high aquifer-scale proportion for inorganic constituents mainly reflected the high aquifer-scale proportions of boron. Inorganic constituents with secondary maximum contaminant levels were detected at high relative-concentrations in 13 percent of the primary aquifer system and at moderate relative-concentrations in 10 percent of the system. The constituents present at high relative-concentrations included iron and manganese. Organic constituents with human-health benchmarks were not detected at high relative-concentrations, but were detected at moderate relative-concentrations in 1.9 percent of the primary aquifer system. The 1.9 percent reflected a spatially weighted moderate aquifer-scale proportion for the gasoline additive methyl tert-butyl ether. Of the 148 organic constituents analyzed, 14 constituents were detected. Only one organic constituent had a detection frequency of greater than 10 percent—the trihalomethane, chloroform. The second component of this study, the understanding assessment , identified the natural and human factors that may have affected the groundwater quality in the KLAM study unit by evaluating statistical correlations between water-quality constituents and potential explanatory factors. The potential explanatory factors evaluated were aquifer lithology, land use, hydrologic conditions, depth, groundwater age, and geochemical conditions. Results of the statistical evaluations were used to explain the occurrence and distribution of constituents in the KLAM study unit. Groundwater age distribution (modern, mixed, or pre-modern), redox class (oxic, mixed, or anoxic), and dissolved oxygen concentration were the explanatory factors that best explained occurrence patterns of the inorganic constituents. High concentrations of boron were found to be associated with groundwater classified as mixed or pre-modern with respect to groundwater age. Boron was also negatively correlated to dissolved oxygen and positively correlated to specific conductance. Iron and manganese concentrations were strongly associated with low dissolved oxygen concentrations, anoxic and mixed redox classifications, and pre-modern groundwater. Specific conductance concentrations were found to be related to pre-modern groundwater, low dissolved oxygen concentrations, and high pH. Chloroform was selected for additional evaluation in the understanding assessment because it was detected in more than 10 percent of wells sampled in the KLAM study unit. Septic tank density was the only explanatory factor that was found to relate to chloroform concentrations.

California↗

USGS2013

Modeling the long-term fate of agricultural nitrate in groundwater in the San Joaquin Valley, California

Nitrate contamination of groundwater systems used for human water supplies is a major environmental problem in many parts of the world. Fertilizers containing a variety of reduced nitrogen compounds are commonly added to soils to increase agricultural yields. But the amount of nitrogen added during fertilization typically exceeds the amount of nitrogen taken up by crops. Oxidation of reduced nitrogen compounds present in residual fertilizers can produce substantial amounts of nitrate which can be transported to the underlying water table. Because nitrate concentrations exceeding 10 mg/L in drinking water can have a variety of deleterious effects for humans, agriculturally derived nitrate contamination of groundwater can be a serious public health issue. The Central Valley aquifer of California accounts for 13 percent of all the groundwater withdrawals in the United States. The Central Valley, which includes the San Joaquin Valley, is one of the most productive agricultural areas in the world and much of this groundwater is used for crop irrigation. However, rapid urbanization has led to increasing groundwater withdrawals for municipal public water supplies. That, in turn, has led to concern about how contaminants associated with agricultural practices will affect the chemical quality of groundwater in the San Joaquin Valley. Crop fertilization with various forms of nitrogen-containing compounds can greatly increase agricultural yields. However, leaching of nitrate from soils due to irrigation has led to substantial nitrate contamination of shallow groundwater. That shallow nitrate-contaminated groundwater has been moving deeper into the Central Valley aquifer since the 1960s. Denitrification can be an important process limiting the mobility of nitrate in groundwater systems. However, substantial denitrification requires adequate sources of electron donors in order to drive the process. In many cases, dissolved organic carbon (DOC) and particulate organic carbon (POC) are the primary electron donors driving active denitrification in groundwater. The purpose of this chapter is to use a numerical mass balance modeling approach to quantitatively compare sources of electron donors (DOC, POC) and electron acceptors (dissolved oxygen, nitrate, and ferric iron) in order to assess the potential for denitrification to attenuate nitrate migration in the Central Valley aquifer.

California↗

USGS2013

Estimating irrigation water demand using an improved method and optimizing reservoir operation for water supply and hydropower generation: a case study of the Xinfengjiang reservoir in southern China

The ever-increasing demand for water due to growth of population and socioeconomic development in the past several decades has posed a worldwide threat to water supply security and to the environmental health of rivers. This study aims to derive reservoir operating rules through establishing a multi-objective optimization model for the Xinfengjiang (XFJ) reservoir in the East River Basin in southern China to minimize water supply deficit and maximize hydropower generation. Additionally, to enhance the estimation of irrigation water demand from the downstream agricultural area of the XFJ reservoir, a conventional method for calculating crop water demand is improved using hydrological model simulation results. Although the optimal reservoir operating rules are derived for the XFJ reservoir with three priority scenarios (water supply only, hydropower generation only, and equal priority), the river environmental health is set as the basic demand no matter which scenario is adopted. The results show that the new rules derived under the three scenarios can improve the reservoir operation for both water supply and hydropower generation when comparing to the historical performance. Moreover, these alternative reservoir operating policies provide the flexibility for the reservoir authority to choose the most appropriate one. Although changing the current operating rules may influence its hydropower-oriented functions, the new rules can be significant to cope with the increasingly prominent water shortage and degradation in the aquatic environment. Overall, our results and methods (improved estimation of irrigation water demand and formulation of the reservoir optimization model) can be useful for local watershed managers and valuable for other researchers worldwide.

Xinfengjiang Reservoir↗

USGS2013

Groundwater quality in the Madera and Chowchilla subbasins of the San Joaquin Valley, California

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s untreated groundwater quality and increases public access to groundwater-quality information. The Madera and Chowchilla subbasins of the San Joaquin Valley constitute one of the study units being evaluated. The Madera-Chowchilla study unit is about 860 square miles and consists of the Madera and Chowchilla groundwater subbasins of the San Joaquin Valley Basin (California Department of Water Resources, 2003; Shelton and others, 2009). The study unit has hot, dry summers and cool, moist winters. Average annual rainfall ranges from 11 to 15 inches, most of which occurs between November and February. The main surface-water features in the study unit are the San Joaquin, Fresno, and Chowchilla Rivers, and the Madera and Chowchilla canals. Land use in the study unit is about 69 percent (%) agricultural, 28% natural (mainly grasslands), and 3% urban. The primary crops are orchards and vineyards. The largest urban area is the city of Madera. The primary aquifer system is defined as those parts of the aquifer corresponding to the perforated intervals of wells listed in the California Department of Public Health (CDPH) database. In the Madera-Chowchilla study unit, these wells typically are drilled to depths between 200 and 800 feet, consist of a solid casing from land surface to a depth of about 140 to 400 feet, and are perforated below the solid casing. Water quality in the primary aquifer system may differ from that in the shallower and deeper parts of the aquifer system. The primary aquifer system in the study unit consists of Quaternary-age alluvial-fan and fluvial deposits that were formed by the rivers draining the Sierra Nevada. Sediments consist of gravels, sands, silts, and clays and generally are coarser closest to the Sierra Nevada and become finer towards the center of the basin. The structure and composition of the deposits in the Madera-Chowchilla study unit are different from those in other parts of the eastern San Joaquin Valley because the Fresno and Chowchilla Rivers primarily drain the Sierra Nevada foothills, whereas the larger rivers drain higher elevations with greater sediment supply. These differences in the sources of sediments are important because they may affect the groundwater chemistry and the physical structure of the sedimentary deposits. Some of the clay layers are lacustrine deposits, the most extensive of which, the Corcoran Clay, underlies the western part of the study unit and divides the primary aquifer system into an unconfined to semi-confined upper system and a largely confined lower system. Regional lateral flow of groundwater is southwest towards the valley trough. Irrigation return flows are the major source of groundwater recharge, and groundwater pumping is the major source of discharge. Groundwater on a lateral flow path may be repeatedly extracted by pumping wells and reapplied at the surface multiple times before reaching the valley trough, resulting in a substantial component of downward vertical flow (Burow and others, 2004; Phillips and others, 2007; Faunt, 2009). This flow pattern enhances movement of water from shallow depths to the primary aquifer system.

California↗

USGS2013

Mapping monkeypox transmission risk through time and space in the Congo Basin

Monkeypox is a major public health concern in the Congo Basin area, with changing patterns of human case occurrences reported in recent years. Whether this trend results from better surveillance and detection methods, reduced proportions of vaccinated vs. non-vaccinated human populations, or changing environmental conditions remains unclear. Our objective is to examine potential correlations between environment and transmission of monkeypox events in the Congo Basin. We created ecological niche models based on human cases reported in the Congo Basin by the World Health Organization at the end of the smallpox eradication campaign, in relation to remotely-sensed Normalized Difference Vegetation Index datasets from the same time period. These models predicted independent spatial subsets of monkeypox occurrences with high confidence; models were then projected onto parallel environmental datasets for the 2000s to create present-day monkeypox suitability maps. Recent trends in human monkeypox infection are associated with broad environmental changes across the Congo Basin. Our results demonstrate that ecological niche models provide useful tools for identification of areas suitable for transmission, even for poorly-known diseases like monkeypox.

PLoS ONE↗

USGS2017

Retrospective analysis of the epidemiologic literature, 1990–2015, on wildlife-associated diseases from the Republic of Korea

To assess the status of research on wildlife diseases in the Republic of Korea (ROK) and to identify trends, knowledge gaps, and directions for future research, we reviewed epidemiologic publications on wildlife-associated diseases in the ROK. We identified a relatively small but rapidly increasing body of literature. The majority of publications were focused on public or livestock health and relatively few addressed wildlife health. Most studies that focused on human and livestock health were cross-sectional whereas wildlife health studies were mostly case reports. Fifteen diseases notifiable to the World Organisation for Animal Health were identified and 21 diseases were identified as notifiable to either the Korean Ministry of Health, Welfare, and Family Affairs or the Korean Ministry of Agriculture. Two diseases were reported as occurring as epidemics; highly pathogenic avian influenza (HPAI) and virulent Newcastle disease. Six diseases or disease agents were described in the literature as emerging including HPAI, rabies, Babesia microti , avian coronaviruses, scrub typhus, and severe fever thrombocytopenia syndrome virus. The diseases for which there were the largest number of publications were HPAI and rabies. The majority of wildlife-associated zoonotic disease publications focused on food-borne parasitic infections or rodent-associated diseases. Several publications focused on the potential of wildlife as reservoirs of livestock diseases; in particular, water deer ( Hydropotes inermis ) and wild boar ( Sus scrofa ). In contrast, there were few publications on diseases of concern for wildlife populations or research to understand the impacts of these diseases for wildlife management. Increased focus on prospective studies would enhance understanding of disease dynamics in wildlife populations. For the high-consequence diseases that impact multiple sectors, a One Health approach, with coordination among the public health, agricultural, and environmental sectors, would be important. This type of review can provide useful information for countries or regions planning or implementing national wildlife health programs.

Journal of Wildlife Diseases↗

USGS2012

Groundwater quality in the Colorado River basins, California

Arizona, California↗

USGS2012

Groundwater quality in Coachella Valley, California

California↗