SEARCH · Geology Reports

Results for “Plant Biology”

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 559 records · Page 31Linked to original sources

USGS2001

Snow cover and snow goose Anser caerulescens caerulescens distribution during spring migration

Arctic geese often use spring migration stopover areas when feeding habitats are partially snow covered. Melting of snow during the stopover period causes spatial and temporal variability in distribution and abundance of feeding habitat. We recorded changes in snow cover and lesser snow goose Anser caerulescens caerulescens distribution on a spring migration stopover area in south-central Alaska during aerial surveys in 1993-1994. Our objectives were to determine whether geese selected among areas with different amounts of snow cover and to assess how temporal changes in snow cover affected goose distribution. We also measured temporal changes in chemical composition of forage species after snow melt. We divided an Arc/Info coverage of the approximately 210 km 2 coastal stopover area into 2-km 2 cells, and measured snow cover and snow goose use of cells. Cells that had 10-49.9% snow cover were selected by snow geese, whereas cells that lacked snow cover were avoided. In both years, snow cover diminished along the coast between mid-April and early May. Flock distribution changed as snow geese abandoned snow-free areas in favour of cells where snow patches were interspersed with bare ground. Snow-free areas may have been less attractive to geese because available forage had been quickly exploited as bare ground was exposed, and because soils became drier making extraction of underground forage more difficult. Fiber content of two forage species increased whereas non-structural carbohydrate concentrations of forage plants appeared to diminish after snow melt, but changes in nutrient concentrations likely occurred too slowly to account for abandonment of snow-free areas by snow geese.

Alaska↗

USGS2011

Invasive Plant Management in the United States National Wildlife Refuge

I nvasive species pose a significant challenge to the National Wildlife Refuge System and have been identified as the single most important threat to habitat management on refuges. At present, it is estimated that over 2 million acres of refuge lands are invaded by invasive plants . The current and potential costs of controlling invasive plants , as well as monitoring and restoring refuge lands, are significant both financially and ecologically. Budgetary expenditures for invasive species projects in FY 2009 totaled $18.4 million. A number of strategies are used to confront this threat and have resulted in success on a variety of levels. The Refuge System utilizes key partnerships, invasive species strike teams, and a dedicated cadre of volunteers to implement projects that incorporate mechanical, chemical and biological control methods.

Book chapter↗

USGS2016

Report A: Fish and habitat assessment in Rock Creek, Klickitat County, Washington, June 2013-December 2015

The U.S. Geological Survey (USGS) and the Yakama Nation have collaborated in the Rock Creek subbasin, southeastern, Washington since 2009 to assess steelhead (Oncorynchus mykiss) populations and habitat conditions. Rock Creek, flows south to the Columbia River at river kilometer (rkm) 368. During 2015, a habitat survey was conducted, and monitoring of Passive Integrated Transponder (PIT)-tagged salmonids in the Rock Creek subbasin continued. Two multiplexing PIT-tag interrogation systems (PTISs) were installed in Rock Creek in the fall of 2009 to evaluate timing and degree of salmonid movement, smolting success, stray rates, and other life history attributes. These have been monitored every year since, during the spring, fall, and winter months. Returning adult steelhead detection histories are summarized from past Rock Creek PIT-tagging efforts. Detection histories and detection efficiencies were used to estimate a smolt-to-adult return rate (SAR) for Rock Creek PIT-tagged steelhead (tagged from 2009 to 2012) that ranged from 2.2% to 5.5%. Additionally, a SAR was also estimated for Rock Creek PIT-tagged steelhead returning to Bonneville Dam, Columbia River (rkm 235). The SAR rate to Bonneville Dam was always higher (2.4% to 10.4%), indicating straying of adults to other sites for spawning potentially further upstream or in other tributaries, or pre-spawn mortality. Twenty-two Rock Creek PIT-tagged steelhead were detected returning to Rock Creek and 35 were detected at Bonneville Dam from past tagging efforts (2009 – 2012). Monitoring of the Rock Creek PTISs [Rock Creek Lower (RCL) and Rock Creek Squaw (RCS)] provide evidence for PIT-tagged salmonid use from fish tagged outside of Rock Creek subbasin (out-of-basin) origins. A total of 82 out-of-basin PIT-tagged fish have been detected at the Rock Creek PTISs since installation. The habitat survey was conducted in Rock Creek from September 16 to October 7, 2015. The survey started at rkm 2 and continued upstream to rkm 29.3, and included portions of the major tributaries, ranging from 1 to 9 rkm survey length upstream from their confluence. During the survey, we measured the lengths of all dry and non-pool wet sections, and for pools: the length, wetted width, average residual depth, maximum residual depth, and temperature. During the 2015 survey of Rock Creek, 38% of the river between rkm 2 and 29 was classified as dry, with a higher relative proportion (57%) of dry being in the lower river section (rkm 2-13) than the upper river section (33%, rkm 14-22). This was higher than during survey years 2010 to 2012, which ranged from 29% to 43% in the lower river. As a result of the increase in dry area the percent of non-pool wet habitat was less (22%) than previous years (range 34% to 43%), as well as the percent of pools (21%). However, more river kilometers were surveyed in the lower river section (rkm 2-13) than previous years. For the 2015 survey length (rkm 2 to 29), 19% was classified as pools and 43% was non-pool wet. This work informs potential restoration actions by identifying the persistent pools across years and in years of low water flow (i.e., 2015). This work also provides a baseline to evaluate effectiveness of future restoration actions. Potential restoration actions could include headwater and upland restoration to improve base flows and pool habitat enhancement, through increased structure and vegetation plantings for increased cover. The Rock Creek steelhead population remains to be an important cultural resource for the Rock Creek Band of the Yakama Nation Tribe. The Rock Creek steelhead population is part of the Cascades Eastern Slope major population group (MPG), one of four MPGs contributing to the Middle Columbia steelhead distinct population segment (DPS). The National Marine Fisheries Service recovery plan for Rock Creek (NMFS 2009a) identifies an overall biological recovery goal for Rock Creek steelhead to contribute to recovery of the Mid-Columbia D

Washington↗

USGS2012

Uncertainty in assessing the impacts of global change with coupled dynamic species distribution and population models

Concern over rapid global changes and the potential for interactions among multiple threats are prompting scientists to combine multiple modelling approaches to understand impacts on biodiversity. A relatively recent development is the combination of species distribution models, land‐use change predictions, and dynamic population models to predict the relative and combined impacts of climate change, land‐use change, and altered disturbance regimes on species' extinction risk. Each modelling component introduces its own source of uncertainty through different parameters and assumptions, which, when combined, can result in compounded uncertainty that can have major implications for management. Although some uncertainty analyses have been conducted separately on various model components – such as climate predictions, species distribution models, land‐use change predictions, and population models – a unified sensitivity analysis comparing various sources of uncertainty in combined modelling approaches is needed to identify the most influential and problematic assumptions. We estimated the sensitivities of long‐run population predictions to different ecological assumptions and parameter settings for a rare and endangered annual plant species ( Acanthomintha ilicifolia , or San Diego thornmint). Uncertainty about habitat suitability predictions, due to the choice of species distribution model, contributed most to variation in predictions about long‐run populations.

California↗

USGS2020

From pools to flow: The PROMISE framework for new insights on soil carbon cycling in a changing world

Soils represent the largest terrestrial reservoir of organic carbon, and the balance between soil organic carbon (SOC) formation and loss will drive powerful carbon‐climate feedbacks over the coming century. To date, efforts to predict SOC dynamics have rested on pool‐based models, which assume classes of SOC with internally homogenous physicochemical properties. However, emerging evidence suggests that soil carbon turnover is not dominantly controlled by the chemistry of carbon inputs, but rather by restrictions on microbial access to organic matter in the spatially heterogeneous soil environment. The dynamic processes that control the physicochemical protection of carbon translate poorly to pool‐based SOC models; as a result, we are challenged to mechanistically predict how environmental change will impact movement of carbon between soils and the atmosphere. Here, we propose a novel conceptual framework to explore controls on belowground carbon cycling: P robabilistic R epresentation of O rganic M atter I nteractions within the S oil E nvironment (PROMISE). In contrast to traditional model frameworks, PROMISE does not attempt to define carbon pools united by common thermodynamic or functional attributes. Rather, the PROMISE concept considers how SOC cycling rates are governed by the stochastic processes that influence the proximity between microbial decomposers and organic matter, with emphasis on their physical location in the soil matrix. We illustrate the applications of this framework with a new biogeochemical simulation model that traces the fate of individual carbon atoms as they interact with their environment, undergoing biochemical transformations and moving through the soil pore space. We also discuss how the PROMISE framework reshapes dialogue around issues related to SOC management in a changing world. We intend the PROMISE framework to spur the development of new hypotheses, analytical tools, and model structures across disciplines that will illuminate mechanistic controls on the flow of carbon between plant, soil, and atmospheric pools.

Global Change Biology↗

USGS2014

Symbiotic regulation of plant growth, development and reproduction

The growth and development of rice ( Oryzae sativa ) seedlings was shown to be regulated epigenetically by a fungal endophyte. In contrast to un-inoculated (nonsymbiotic) plants, endophyte colonized (symbiotic) plants preferentially allocated resources into root growth until root hairs were well established. During that time symbiotic roots expanded at five times the rate observed in nonsymbiotic plants. Endophytes also influenced sexual reproduction of mature big sagebrush ( Artemisia tridentata ) plants. Two spatially distinct big sagebrush subspecies and their hybrids were symbiotic with unique fungal endophytes, despite being separated by only 380m distance and 60 m elevation. A double reciprocal transplant experiment of parental and hybrid plants, and soils across the hybrid zone showed that fungal endophytes interact with the soils and different plant genotypes to confer enhanced plant reproduction in soil native to the endophyte and reduced reproduction in soil alien to the endophyte. Moreover, the most prevalent endophyte of the hybrid zone reduced the fitness of both parental subspecies. Because these endophytes are passed to the next generation of plants on seed coats, this interaction provides a selective advantage, habitat specificity, and the means of restricting gene flow, thereby making the hybrid zone stable, narrow, and potentially leading to speciation.

Communitative and Integrative Biology↗

USGS2003

Metal uptake by phytoplankton during a bloom in South San Francisco Bay: Implications for metal cycling in estuaries

The 1994 spring phytoplankton bloom in South San Francisco Bay caused substantial reductions in concentrations of dissolved Cd, Ni, and Zn, but not Cu. We estimate that the equivalent of ~60% of the total annual input of Cd, Ni, and Zn from local waste‐water treatment plants is cycled through the phytoplankton in South Bay. The results suggest that processes that affect phytoplankton bloom frequency or intensity in estuaries (e.g. nutrient enrichment) may also affect metal trapping. The bloom was characterized by hydrographic surveys conducted at weekly intervals for 9 weeks. Metal samples were collected from the water column on three occasions, timed to bracket the period when the bloom was predicted. Factors that might confound observations of biological influences, such as freshwater inputs, were relatively constant during the study. Before the bloom, concentrations of dissolved Cd were 0.81 ± 0.02 nmol kg −1 , Zn concentrations were 19.8 ± 1.5 nmol kg −1 , Ni were 42 ± 1.4 nmol kg −1 , and Cu were 37 ± 1.4 nmol kg −1 . These values are elevated relative to riverine and coastal end‐members, reflecting inputs from wastewater and(or) sediments. At the height of the bloom, dissolved Zn, Cd, and Ni were reduced to 19, 50, and 75% of their prebloom concentrations, respectively. Dissolved Cu concentrations increased 20%. The mass of Cd taken up by phytoplankton was similar to the mass of Cd removed from solution if particle settling was considered, and Cd concentrations estimated in phytoplankton were higher than concentrations in suspended particulate material (SPM). Particulate concentrations of Zn and Ni during the bloom appeared to be dominated by the influence of changes in resuspension of Zn and Ni‐rich sediments.

California↗

USGS2026

Amphibian use of recently created wetlands in the Palouse region of northern Idaho, USA

Human development has resulted in the loss of natural wetlands in many regions and thus has led to amphibian habitat loss. Human-constructed wetlands are increasingly prevalent, particularly in human-modified landscapes, and can be used as breeding habitats by amphibians. It is important to identify factors influencing amphibian use of constructed wetlands to guide future wetland creation efforts. We examined wetland- and landscape-level factors influencing the presence and reproduction of native amphibians in 33 recently created (2–11 yold) wetlands within an urban-agricultural interface in northern Idaho, USA. We recorded wetland age, perimeter vegetation, and percentage of surrounding land cover as covariates and modeled detection and occupancy using Bayesian Multi-scale Occupancy Models for the three species we detected: Sierran Treefrog ( Pseudacris sierra ), Colombia Spotted Frog ( Rana luteiventris ), and Long-Toed Salamander ( Ambystoma macrodactylum ). Our results indicate that these three species can rapidly colonize recently created wetlands in an urban-agricultural interface. The effects of wetland- and landscape-scale features varied across species. Colombia Spotted Frog occupancy was greatest in older wetlands with some evidence for a negative association with more urbanized landscapes. Long Toed Salamanders and Sierran Treefrogs were not associated with wetland age but also showed some evidence of negative associations with urbanization. Long-Toed Salamanders showed evidence of using less vegetated wetlands while Sierran Treefrogs showed evidence of using more vegetated wetlands. Our results are consistent with multiple studies showing that wetlands in human-modified landscapes can provide amphibian breeding habitat, and they suggest that including vegetation plantings within recently created wetlands may promote amphibian colonization. Anecdotal observations also indicate that designing wetlands with sufficient hydroperiod for metamorphoses may be important for ensuring that newly created wetlands benefit amphibian populations.

Idaho↗

USGS1994

Characterization of ecological risks at the Milltown Reservoir-Clark Fork River Sediments Superfund Site, Montana

A comprehensive field and laboratory approach to the ecological risk assessment for the Milltown Reservoir-Clark Fork River Sediments Site, a Superfund site in the Rocky Mountains of Montana, has been described in the preceding reports of this series. The risk assessment addresses concerns over the ecological impacts of upstream releases of mining wastes to fisheries of the upper Clark Fork River (CFR) and the benthic and terrestrial habitats further downstream in Milltown Reservoir. The risk characterization component of the process integrated results from a triad of information sources: (a) chemistry studies of environmental media to identify and quantify exposures of terrestrial and aquatic organisms to site-related contaminants; (b) ecological or population studies of terrestrial vegetation, birds, benthic communities, and fish; and (c) in situ and laboratory toxicity studies with terrestrial and aquatic invertebrates and plants, small mammals, amphibians, and fish exposed to contaminated surface water, sediments, wetland soils, and food sources. Trophic transfer studies were performed on waterfowl, mammals, and predatory birds using field measurement data on metals concentrations in environmental media and lower trophic food sources. Studies with sediment exposures were incorporated into the Sediment Quality Triad approach to evaluate risks to benthic ecology. Overall results of the wetland and terrestrial studies suggested that acute adverse biological effects were largely absent from the wetland; however, adverse effects to reproductive, growth, and physiological end points of various terrestrial and aquatic species were related to metals exposures in more highly contaminated depositional areas. Feeding studies with contaminated diet collected from the upper CFR indicated that trout are at high risk from elevated metals concentrations in surface water, sediment, and aquatic invertebrates. Integration of chemical analyses with toxicological and ecological evaluations of metal effects on the wetland and fishery has provided an important foundation for environmental decisions at this site.

Montana↗

USGS2020

Climate dipoles as continental drivers of plant and animal populations

Ecological processes, such as migration and phenology, are strongly influenced by climate variability. Studying these processes often relies on associating observations of animals and plants with climate variability indices, such as the El Niño–Southern Oscillation. A characteristic of climate indices is the simultaneous emergence of opposite extremes of temperature and precipitation across continental scales, known as climate dipoles. The role of climate dipoles in shaping ecological and evolutionary processes has been largely overlooked. We review emerging evidence that climate dipoles can entrain species dynamics, and offer a framework for identifying ecological dipoles using broad-scale biological data. Given future changes in climatic and atmospheric processes, climate and ecological dipoles will likely shift in their intensity, distribution, and timing.

Trends in Ecology and Evolution↗

USGS2019

Water velocity regulates macro-consumer herbivory on the benthic macrophyte Podostemum ceratophyllum Michx.

1) Macrophytes influence aquatic ecosystems by increasing habitat complexity and providing trophic resources for aquatic fauna. While herbivory on freshwater macrophytes is widely documented in lakes, low-velocity riverine habitats, the influence of herbivory on macrophytes in higher-velocity habitats has rarely been examined. 2) We investigated the hypothesis that high water velocity can reduce consumption rates of the submerged macrophyte, Podostemum ceratophyllum, an angiosperm which grows attached to stable substrates in high water-velocity riverine habitats throughout eastern North America. 3) We estimated grazing-pressure by conducting short-term (up to 77-d) transplant and consumer-exclosure experiments, and quantified changes in Podostemum stem length when the plant was eposed to low (<0.5 m s-1) and higher velocities in two Piedmont rivers in Georgia (USA). Podostemum transplanted into low-velocity habitats rapidly lost stem length unless macro-consumers were excluded from accessing the plant. In contrast, Podostemum tranplanted into high-velocity habitats showed little change or gained stem length. 4) We estimated that 85% (67 – 98%; 95% credible interval) of the daily stem growth (0.026 cm cm-1 day-1) in Podostemum was consumed during a 77-d paired consumer-access versus exclosure experiment conducted in mean water velocities of 0.35-0.5 m s-1. We also found a positive relation (R2 = 0.58) between Podostemum biomass and water velocity (ranging between ~0.1 -1.4 m s-1) in benthic samples collected over a two-month period. 5) We conclude that high water velocity reduces herbivory on Podostemum, and that water velocity can thus control the acural of benthic plant biomass and the movement of plant-derived materials through benthic food webs. Our research has implications for estimating resource storage and flux in lotic food webs and illuminates a mechanism by which flow regulation and management may affect basal resources in rivers.

Georgia↗

USGS2020

Multiple mechanisms determine the effect of warming on plant litter decomposition in a dryland

In drylands, where soil fertility is typically low, plant litter decomposition provides particularly critical carbon and nitrogen inputs into soil. Although climate change is projected to increase the already large global extent of drylands, it is unknown how warmer temperatures will affect core ecosystem processes, such as plant litter decomposition, in these systems. To address this key unknown, we conducted a litterbag study in a long-term dryland warming experiment in southeastern Utah, USA. Unexpectedly, we did not find an overall effect of warming on leaf litter mass loss over time. Instead, our results indicated both positive and negative effects of warming on mass loss which offset one another. In particular, our findings suggested that a warming-induced degradation of biological soil crusts (soil surface community of mosses, lichens, and/or cyanobacteria that live in drylands worldwide) increased soil-litter mixing, thereby accelerating decomposition. Results also suggested that warming-induced decreases in litter moisture slowed decomposition. In addition to assessing mass loss, we found that warming lowered the carbon-to-nitrogen ratio of the decomposing litter. These results showed that warming did not alter the total litter mass-loss rates in this ecosystem, but that decomposition patterns were affected through more nuanced changes to both the biological and physical environment of dryland soils.

Utah↗

USGS2013

Biodiversity losses and conservation trade-offs: Assessing future urban growth scenarios for a North American trade corridor

The Sonoran Desert and Apache Highlands ecoregions of North America are areas of exceptionally high plant and vertebrate biodiversity. However, much of the vertebrate biodiversity is supported by only a few vegetation types with limited distributions, some of which are increasingly threatened by changing land uses. We assessed the impacts of two future urban growth scenarios on biodiversity in a binational watershed in Arizona, USA and Sonora, Mexico. We quantified and mapped terrestrial vertebrate species richness using Wildlife Habitat Relation models and validated the results with data from National Park Service biological inventories. Future urban growth, based on historical trends, was projected to the year 2050 for 1) a “Current Trends” scenario and, 2) a “Megalopolis” scenario that represented a transnational growth corridor with open-space conservation attributes. Based on Current Trends, 45% of existing riparian woodland (267 of 451species), and 34% of semi-desert grasslands (215 of 451 species) will be lost, whereas, in the Megalopolis scenario, these types would decline by 44% and 24% respectively. Outcomes of the two models suggest a trade-off at the taxonomic class level: Current Trends would reduce and fragment mammal and herpetofauna habitat, while Megalopolis would result in loss of avian-rich riparian habitat.

International Journal of Biodiversity Science, Eco↗

USGS2015

Marshes to mudflats—Effects of sea-level rise on tidal marshes along a latitudinal gradient in the Pacific Northwest

Summary In the Pacific Northwest, coastal wetlands support a wealth of ecosystem services including habitat provision for wildlife and fisheries and flood protection. The tidal marshes, mudflats, and shallow bays of coastal estuaries link marine, freshwater, and terrestrial habitats, and provide economic and recreational benefits to local communities. Climate change effects such as sea-level rise are altering these habitats, but we know little about how these areas will change over the next 50–100 years. Our study examined the effects of sea-level rise on nine tidal marshes in Washington and Oregon between 2012 and 2015, with the goal of providing scientific data to support future coastal planning and conservation. We compiled physical and biological data, including coastal topography, tidal inundation, vegetation structure, as well as recent and historical sediment accretion rates, to assess and model how sea-level rise may alter these ecosystems in the future. Multiple factors, including initial elevation, marsh productivity, sediment availability, and rates of sea-level rise, affected marsh persistence. Under a low sea-level rise scenario, all marshes remained vegetated with little change in the present configuration of communities of marsh plants or gradually increased proportions of middle-, high-, or transition-elevation zones of marsh vegetation. However, at most sites, mid sea-level rise projections led to loss of habitat of middle and high marshes and a gain of low marshes. Under a high sea-level rise scenario, marshes at most sites eventually converted to intertidal mudflats. Two sites (Grays Harbor and Willapa) seemed to have the most resilience to a high rate of rise in sea-level, persisting as low marsh until at least 2110. Our main model finding is that most tidal marsh study sites are resilient to sea-level rise over the next 50–70 years, but that sea-level rise will eventually outpace marsh accretion and drown most habitats of high and middle marshes by 2110.

California, Oregon, Washington↗

USGS2005

Effects of rain gardens on the quality of water in the Minneapolis-St. Paul metropolitan area of Minnesota, 2002-04

Rain gardens are a popular method of managing runoff while attempting to provide aesthetic and environmental benefits. Five rain-garden sites in the Minneapolis – Saint Paul metropolitan area of Minnesota were instrumented to evaluate the effects of this water-management system on surface and subsurface water quality. Most of these sites were in suburban locations and frequently in newer developments. Because of this they were affected by changing hydrology during the course of this study. Less-than-normal precipitation during much of the study may have resulted in samples that may not be representative of normal conditions. However, the resulting data indicate that properly designed rain gardens enhance infiltration and can reduce concentrations of dissolved ions relative to background conditions. The runoff events in one rain garden and several runoff events in the other rain gardens produced no sampled overflow during this study because the gardens captured all of the inflow, which subsequently infiltrated beneath the land surface, evaporated, or transpired through garden vegetation. Where measured, overflow had reduced concentrations of suspended solids and most nutrient species associated with particulate material, as compared to inflow. Many of these materials settle to the bottom of the rain garden, and some nutrients may be assimilated by the plant community. Site design, including capacity relative to drainage area and soil permeability, is an important consideration in the efficiency of rain-garden operation. Vegetation type likely affects the infiltration capacity, nutrient uptake, and evapotranspiration of a rain garden and probably the resulting water quality. The long-term efficiency of rain gardens is difficult to determine from the results of this study because most are still evolving and maturing in relation to their hydrologic, biologic, and chemical setting. Many resource managers have questioned what long-term maintenance will be needed to keep rain gardens operating effectively. Additional or continued studies could address many of these concerns.

Minnesota↗

USGS2014

Spatiotemporal variations in estrogenicity, hormones, and endocrine-disrupting compounds in influents and effluents of selected wastewater-treatment plants and receiving streams in New York, 2008-09

Endocrine-disrupting compounds (EDCs) in wastewater effluents have been linked to changes in sex ratios, intersex (in males), behavioral modifications, and developmental abnormalities in aquatic organisms. Yet efforts to identify and regulate specific EDCs in complex mixtures are problematic because little is known about the estrogen activity (estrogenicity) levels of many common and emerging contaminants. The potential effects of EDCs on the water quality and health of biota in streams of the New York City water supply is especially worrisome because more than 150 wastewater-treatment plants (WWTPs) are permitted to discharge effluents into surface waters and groundwaters of watersheds that provide potable water to more than 9 million people. In 2008, the U.S. Geological Survey (USGS), the New York State Department of Environmental Conservation (NYSDEC), New York State Department of Health (NYSDOH), and New York City Department of Environmental Protection (NYCDEP) began a pilot study to increase the understanding of estrogenicity and EDCs in effluents and receiving streams mainly in southeastern New York. The primary goals of this study were to document and assess the spatial and temporal variability of estrogenicity levels; the effectiveness of various treatment-plant types to remove estrogenicity; the concentrations of hormones, EDCs, and pharmaceuticals, personal care products (PPCPs); and the relations between estrogenicity and concentrations of hormones, EDCs, and PPCPs. The levels of estrogenicity and selected hormones, non-hormone EDCs, and PPCPs were characterized in samples collected seasonally in effluents from 7 WWTPs, once or twice in effluents from 34 WWTPs, and once in influents to 6 WWTPs. Estrogenicity was quantified, as estradiol equivalents, using both the biological e-screen assay and a chemical model. Results generally show that (1) estrogenicity levels in effluents varied spatially and seasonally, (2) a wide range of known and unknown EDCs were present in both WWTP effluents and receiving streams, (3) some effluents may be important sources of estrogenicity in weakly diluted streams, (4) measured levels of biological estrogenicity were often higher than estimated levels of chemical estrogenicity, and (5) the type of treatment had a large effect on the removal efficacy, and consequently, the estrogenicity levels observed in treated effluents.

New York↗

USGS2025

A comprehensive assessment of membrane bioreactor contaminant removal efficacy through analytical chemistry, fish exposures, and microbiome characterization

Treated municipal wastewater effluent is an important pathway for Contaminants of Emerging Concern (CEC) to enter aquatic ecosystems. As the aging wastewater infrastructure in many industrialized countries requires upgrades or replacement, assessing new treatment technologies in the context of CEC effects may provide additional support for science-based resource management. Here, we used three lines of evidence, analytical chemistry, fish exposure experiments, and fish and water microbiome analysis, to assess the effectiveness of membrane bioreactor treatment (MBR) to replace traditional activated sludge treatment. To do this, we sampled a municipal wastewater treatment plant with a split wastewater stream, a portion of which was treated with an MBR and another via an oxidation ditch (OXI). The OXI and MBR treatments substantially reduced most measured CECs compared to the primary effluent (PRI). Only pesticides and some pharmaceuticals were recalcitrant to both secondary treatment methods. While ammonia toxicity of PRI prevented its inclusion in fish exposure experiments, exposure of fish with waters from the OXI or MBR treated wastewater produced only subtle biological differences with no adverse apical outcomes. These findings were consistent with low chemically derived exposure: activity ratios for OXI and MBR. Microbiome analysis of fish and wastewater highlighted the significant reduction of microbial abundance and diversity in the MBR treatment compared to all other treatments. The comparable removal efficacy of CECs in MBR makes it an attractive alternative to traditional OXI, especially when MBR may eliminate the need for tertiary treatment for wastewater disinfection.

Environmental Toxicology and Chemistry↗

USGS1996

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Vermejo Project area and the Maxwell National Wildlife Refuge, Colfax County, northeastern New Mexico, 1993

Based on findings of limited studies during 1989-92, a reconnaissance investigation was conducted in 1993 to assess the effects of the Vermejo Irrigation Project on water quality in the area of the project, including the Maxwell National Wildlife Refuge. This project was part of a U.S. Department of the Interior National Irrigation Water-Quality Program to determine whether irrigation drainage has caused or has the potential to cause significant harmful effects on human health, fish, and wildlife and whether irrigation drainage may adversely affect the suitability of water for other beneficial uses. For this study, samples of water, sediment, and biota were collected from 16 sites in and around the Vermejo Irrigation Project prior to, during the latter part of, and after the 1993 irrigation season (April, August-September, and November, respectively). No inorganic constituents exceeded U.S. Environmental Protection Agency drinking-water standards. The State of New Mexico standard of 750 micrograms per liter for boron in irrigation water was exceeded at three sites (five samples), though none exceeded the livestock water standard of 5,000 micrograms per liter. Selenium concentrations exceeded the State of New Mexico chronic standard of 2 micrograms per liter for wildlife and fisheries water in at least eight samples from five sites. Bottom-sediment samples were collected and analyzed for trace elements and compared to concentrations of trace elements in soils of the Western United States. Concentrations of three trace elements at eight sites exceeded the upper values of the expected 95-percent ranges for Western U.S. soils. These included molybdenum at one site, selenium at seven sites, and uranium at four sites. Cadmium and copper concentrations exceeded the National Contaminant Biomonitoring Program 85th percentile in fish from six sites. Average concentrations of selenium in adult brine flies (33.7 μ g/g dry weight) were elevated above concentrations in other invertebrates. Concentrations of other elements were below their respective toxicity levels. Plants, invertebrates, fish, and fish fillets were collected and analyzed. These analyses were compared to diagnostic criteria and to each other to determine the extent of bioaccumulation of trace elements. Plants contained larger dry weight concentrations of aluminum, arsenic, boron, chromium, iron, lead, magnesium, manganese, nickel, and vanadium than invertebrates and fish. Adult brine flies, gathered from playas, contained larger geometric mean dry weight concentrations of boron, magnesium, and selenium than other invertebrates. Of all samples collected, the largest mercury concentrations were found in fish fillets, although these concentrations were below levels of concern. Mercury and selenium bioaccumulation was evident in various habitats of the study area. Biological samples from Natural playa, an endemic wetland, and Half playa, a playa that receives additional water through seepage and irrigation delivery canals, generally had elevated concentrations of boron, iron, magnesium, and selenium than samples from reservoir and river sites. Selenium concentrations were lowest in biota from the two reservoir sites, although a wetland immediately downstream from the dam impounding Lake No. 13 (created by seepage from the reservoir) had elevated concentrations of selenium in biota. The geometric mean selenium concentration of whole-fish samples, except those from Lakes No. 13 and No. 14, exceeded the 5- μ g/g dry weight selenium concentration that demarcates the approximate lower limit of the threshold range of concentrations that have freen associated with adverse effects on piscine reproduction. Biota collected on and in the area around Maxwell National Wildlife Refuge contained concentrations of selenium that are in the lower range of threshold values that have been associated (dietarily) with risks of avian reproductive abnormalities. Bottom-sediment samples from two sites downstream from the irrigation project were collected and analyzed for 23 organic compounds (principally organochlorine pesticide residues). Three compounds were detected at the two sites: DDD was found at 0.2 microgram per kilogram, DDE was detected at 0.1 microgram per kilogram at both sites, and chlordane was detected at 1 microgram per kilogram. None of the 28 whole-fish and fillet samples analyzed for PCB and organochlorine pesticide residues contained any of the 23 organic compounds tested for at concentrations higher than the analytical reporting limit (less than 0.01 μ g/g wet weight). Concentrations of inorganic analytes were generally within established guidelines or expected concentrations for water, sediment, and biota. lirigation-return flows were found to be unrelated to adverse effects in biota.

New Mexico↗