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At least 1,459 records · Page 81Linked to original sources
USGS2010

Using noble gases measured in spring discharge to trace hydrothermal processes in the Norris Geyser Basin, Yellowstone National Park, U.S.A.

Dissolved noble gas concentrations in springs are used to investigate boiling of hydrothermal water and mixing of hydrothermal and shallow cool water in the Norris Geyser Basin area. Noble gas concentrations in water are modeled for single stage and continuous steam removal. Limitations on boiling using noble gas concentrations are then used to estimate the isotopic effect of boiling on hydrothermal water, allowing the isotopic composition of the parent hydrothermal water to be determined from that measured in spring. In neutral chloride springs of the Norris Geyser Basin, steam loss since the last addition of noble gas charged water is less than 30% of the total hydrothermal discharge, which results in an isotopic shift due to boiling of ?? 2.5% ??D. Noble gas concentrations in water rapidly and predictably change in dual phase systems, making them invaluable tracers of gas-liquid interaction in hydrothermal systems. By combining traditional tracers of hydrothermal flow such as deuterium with dissolved noble gas measurements, more complex hydrothermal processes can be interpreted. ?? 2010 Elsevier B.V.

Journal of Volcanology and Geothermal Research↗
USGS2004

Frequency and initiation of debris flows in Grand Canyon, Arizona

Debris flows from 740 tributaries transport sediment into the Colorado River in Grand Canyon, Arizona, creating rapids that control its longitudinal profile. Debris flows mostly occur when runoff triggers failures in colluvium by a process termed “the fire hose effect.” Debris flows originate from a limited number of geologic strata, almost exclusively shales or other clay‐rich, fine‐grained formations. Observations from 1984 through 2003 provide a 20 year record of all debris flows that reached the Colorado River in Grand Canyon, and repeat photography provides a 100 year record of debris flows from 147 tributaries. Observed frequencies are 5.1 events/year from 1984 to 2003, and historic frequencies are 5.0 events/year from 1890 to 1983. Logistic regression is used to model historic frequencies based on drainage basin parameters observed to control debris flow initiation and transport. From 5 to 7 of the 16 parameters evaluated are statistically significant, including drainage area, basin relief, and the height of and gradient below debris flow source areas, variables which reflect transport distance and potential energy. The aspect of the river channel, which at least partially reflects storm movement within the canyon, is also significant. Model results are used to calculate the probability of debris flow occurrence at the river over a century for all 740 tributaries. Owing to the variability of underlying geomorphic controls, the distribution of this probability is not uniform among tributaries of the Colorado River in Grand Canyon.

Arizona↗
USGS2021

Evaluation of dissolved carbon dioxide to stimulate emergence of red swamp crayfish Procambarus clarkii (Decapoda: Cambaridae) from infested ponds

Invasive crayfish have adverse effects on habitats and native species. Control of invasive crayfish populations is a major challenge facing natural resource managers. This study evaluated the effectiveness and optimal conditions for the control agent carbon dioxide (CO2) which can be diffused into water to facilitate capture of red swamp crayfish (Procambarus clarkii; RSC). The efficacy of CO2 shows promise in its use for a variety of invasive aquatic species. Here, we evaluate CO2’s ability to stimulate movements towards the shoreline and/or induce complete terrestrial emergence from outdoor ponds. Twelve pond trials were conducted using three, 0.02-ha experimental ponds at Auburn University, Alabama, USA. Silt fencing was installed on dry land around the perimeter of each pond with the lower 0.3 m of fencing accordion-folded to provide shelter and a collection point for emerging crayfish. Each pond was stocked with 100 RSC before testing. Experimental treatment ponds were then injected with gaseous CO2 using porous air diffusers, whereas control ponds (C ponds) received no CO2. Multiple water quality parameters were monitored hourly. Three independent treatment scenarios with CO2 diffusion were: crayfish captured at the end of trial only (F: final), crayfish captured hourly (H: hourly), and incorporation of continuous inflow of fresh water at a flow rate of 0.2 L/s into the central catch basin to serve as a refuge with crayfish captured hourly (R: refuge). In control ponds, crayfish were captured at the end of trial only. In F ponds, CO2 diffusion for approximately five hours caused an average of 12% of total crayfish to emerge from the water. However, capture efficiency was increased to an average of 45% of total crayfish by increasing collection frequency to every hour and netting submerged crayfish near the water edge in addition to capturing terrestrially emerged crayfish. Presence of a freshwater inflow reduced capture efficiency in R ponds relative to H ponds. Odds of capturing crayfish improved with increased water temperature, increased CO2 concentration and increased crayfish mass. Based on results, we provide a set of predictive equations as well as interactive calculators to help natural resource managers explore several environmental and treatment-related scenarios that predict changes in capture probability in small research ponds. Carbon dioxide shows promises as a tool to increase capture rate of RSC. It is not likely to be 100% effective by itself, but could be a useful component of an integrated management strategy.

Management of Biological Invasions↗
USGS2002

Implications of flood pulse restoration for Populus regeneration on the upper Missouri River

We developed a mass balance flow model to reconstruct unregulated daily peak flows in the National Wild and Scenic reach of the Missouri River, Montana. Results indicated that although the observed frequency of large peak flows has not changed in the post-dam period, their magnitude has been reduced from 40 to 50% as a consequence of flow regulation. Reductions in the magnitude of these flows should reduce the expected frequency of large flood-pulses over a longer time-scale. Results of a two-dimensional hydraulic model indicated that limited cottonwood ( Populus deltoides subsp. Monilifera ) recruitment occurs at relatively small peak discharges, but to maximize establishment of cottonwoods in the Wild and Scenic reach, a threshold of 1850 m 3 /s would be necessary at the Virgelle gauge. Floods of this magnitude or greater lead to establishment of cottonwood seedlings above the zone of frequent ice-drive disturbance. Restoring the frequency, magnitude, duration and timing of these flood pulses would benefit important natural resource values including riparian cottonwood forests and native fish species in the upper Missouri River basin. However, efforts to naturalize flow must be made in the context of a water management system that was authorized and constructed for the primary purposes of flood control, power generation and irrigation. Using the synthesized flow model and flood damage curves, we examined six scenarios for delivering flows ≥1850 m 3 /s to the Wild and Scenic reach. Whereas some scenarios appeared to be politically and economically infeasible, our analysis suggested that there is enough operational flexibility in the system to restore more natural flood pulses without greatly compromising other values.

Missouri River↗
USGS2024

First documentation of grass carp spawning in Lake Erie’s Central Basin

Grass carp ( Ctenopharyngodon idella ) are non-indigenous to North America having been translocated to the United States in the 1960s as a potential non-chemical solution for nuisance aquatic vegetation. Reproductively viable grass carp now exist in many watersheds in the United States. In the Great Lakes basin, grass carp were first discovered in the 1980s with direct confirmation of successful reproduction in 2015 via collection of fertilized grass carp eggs in the Sandusky River. Early life stage monitoring also confirmed reproduction in the Maumee River in 2017. During 2018–2021, no new spawning tributaries were discovered (18 total sampling events in five Great Lakes tributaries). In 2022, fourteen eggs with characteristics similar to grass carp were identified from the Huron River which is a tributary to Lake Erie’s Central Basin. Eggs were identified to species via DNA sequencing and were determined to be grass carp eggs. The confirmation of spawning in the Huron River represents a third spawning tributary in the Lake Erie basin and expands eastward the geographic extent of known grass carp spawning locations. Presently, the ability of the Huron River to support hatching and survival of larval grass carp is unknown. Discovery of the Huron River as a grass carp spawning tributary identifies the value of continued surveillance in Great Lakes tributaries for early life stages and conducting scientific inquiries evaluating the consistency of tributary use and survival of early life stages.

Ohio↗
USGS2021

Spatio-temporal analysis of hypoxia in the Central Basin of Lake Erie of North America

We develop a spatio-temporal geostatistical interpolation framework to estimate hypoxia extent (dissolved oxygen [DO] concentrations below 2 mg/L) with data from a network of DO loggers. The framework uses empirical orthogonal functions and Bayesian kriging to identify the spatially varying temporal pattern and estimate the distribution of hypoxia, including estimation uncertainty. A prototype web application is also developed in R. The framework is applied to analyze spatio-temporal dynamics of DO in the central basin of Lake Erie in North America using data sampled from a logger network placed on the lake bottom during the summers of 2014, 2015, and 2016. Cross-validation results demonstrate that the framework is capable of capturing the dynamic nature of bottom hypoxia over offshore areas, but nearshore areas have poor interpolation performance due to the impacts of complex physical processes such as seiche events. The findings showed that in the central basin, hypoxia started to emerge in early August of 2014, while in 2015 and 2016 hypoxia began in July. The peak hypoxia extent occurred in late September 2014, mid-August 2015, and early September 2016. The prediction error of the overall spatial extent of hypoxia was as large as 25% of the interpolation area based on current logger deployment. Based on the cross-validation and interpolation error, we suggest placing more loggers in nearshore areas to reduce prediction error near the margins of the hypoxic zone.

central Lake Erie↗
USGS2021

Crustal seismic attenuation of the central United States and Intermountain West

Seismic attenuation is generally greater in the western United States (WUS) than the central and eastern United States (CEUS), but the nature of this transition or location of this boundary is poorly constrained. We conduct crustal seismic (Lg) attenuation tomography across a region that stretches from the CEUS across the Rocky Mountains to the Basin and Range using a total of 115,870 amplitude measurements from 106 earthquakes recorded on 544 stations across five frequency bands spanning 0.5–16 Hz. Similar to previous studies, we find higher attenuation in the WUS ( Q 0 ∼ 190) than the nominally CEUS ( Q 0 ∼ 250) and comparatively high attenuation on the Gulf Coast ( Q 0 ∼ 175). Our models defy simple east versus west regionalization, however. Heterogeneity within the Rocky Mountain region—low attenuation in the Colorado Plateau interior and Wyoming Craton ( Q 0 ∼ 230) compared to high attenuation in the southern Rockies ( Q 0 ∼ 110)—exceeds the gross differences between the CEUS and western United States. These province-scale patterns are readily interpreted in terms of intrinsic attenuation. The boundary between the Colorado Plateau and Basin and Range hosts the highest attenuation imaged in the study area ( Q 0 ∼ 90), consistent with localized scattering across contrasting crustal structure. Focused high attenuation in the southern Rockies may represent the effects of represent in situ partial crustal melt. Within the CEUS, second-order bands of comparatively high attenuation align with the Proterozoic Yavapai-Mazatzal suture zone and Midcontinent Rift. This complex attenuation structure defies broad regionalization and suggests a need for path-specific models near these boundaries and for critical infrastructure.

Journal of Geophysical Research: Solid Earth↗
USGS1997

An integrated model for the tectonic development of the frontal Brooks Range and Colville Basin 250 km west of the Trans-Alaska Crustal Transect

We present a kinematic model for the sequence of deformation and sedimentation in the frontal Brooks Range and adjacent Colville Basin in the Etivluk River region, 250 km west of the Trans-Alaska Crustal Transect (TACT). The model is based on a tectonic subsidence analysis of the foreland basin, combined with structural, stratigraphic, and thermal studies of the northern edge of the Brooks Range thrust belt. We interpret six discrete tectonic events that led to the present-day configuration of the thrust belt in this area: (1) emplacement of ophiolitic allochthons over the distal continental margin rocks in Valanginian time, hundreds of kilometers south of this study, (2) Hauterivian uplift of the Barrow Arch rift margin, affecting the northern part of the Colville Basin, (3) Barremian contraction involving emplacement of distal continental margin and ophiolitic allochthons onto the Endicott Mountains allochthon and creation of a southward dipping flexural basin on the North Slope autochthon, (4) mid-Cretaceous exhumation of imbricated rocks in the Brooks Range during northward propagation of the thrust front into the foreland, (5) minor thrusting in Late Cretaceous-Paleocene in the northern foreland to the northern limit of contractional structures, and (6) regional exhumation of the orogen and the foreland in Paleocene-Eocene time. This sequence of deformation agrees well with a simple model of a forward propagating thrust system.

Journal of Geophysical Research B: Solid Earth↗
USGS2012

Geothermal gradients in the conterminous United States

Geothermal gradients from published temperature/depth measurements in drill holes generally deeper than 600 m are used to construct a temperature gradient map of the conterminous United States. The broadly contoured map displays 284 temperature gradients that are applicable to a depth of 2 km. In terms of the number of contoured areas and the fraction of data points having a value not within a contour interval (outliers), the temperature gradient data and associated deep heat flow data have similar measures of contourability. Areally, most of the United States is contoured from 15° to 35°C/km. The eastern United States is generally cooler (average 25°C/km) than the western United States (average 34°C/km), in accordance with broad heat flow trends. Differences between the temperature gradient and heat flow maps are caused by areal differences in rock thermal conductivities. The effect of conductivity on gradients is particularly apparent in the eastern United States where heat flow is relatively constant over large areas. Gradients are elevated where thick, low-conductivity, sedimentary deposits occur such as in the Atlantic Coastal Plain province and in basins in the Allegheny Plateau and the Great Plains provinces. No clear gradient pattern emerges where both heat flow and conductivity vary widely, such as in the northern Basin and Range and Rocky Mountain provinces. Using the temperature gradients determined in this study and associated heat flow values, derived thermal conductivities are calculated for the depth range of a few hundred meters to 2 km; the average conductivity is 2.5±0.8 W/m °C. Some areas show little variation in derived thermal conductivity, while others show a wide range. The Atlantic Coastal Plain, Appalachian Plateaus, Superior Upland, Gulf Coastal Plain, Columbia Plateaus and Cascade Mountains, and Sierra Nevada provinces have restricted ranges of conductivities, which supports the concept of regional conductivities.

Journal of Geophysical Research Solid Earth↗
USGS2019

Gopherus agassizii (Cooper 1861) – Agassiz’s Desert Tortoise, Mojave Desert Tortoise

The Mojave Desert Tortoise, Gopherus agassizii (Family Testudinidae), is a large terrestrial species that can reach >370 mm in straight midline carapace length (CL) but most individuals are smaller. Both sexes reach adulthood at 12 to 21 years and ca. 180 mm CL. The species is sexually dimorphic, with males typically larger than females; sexual characteristics of males become more obvious with increasing size and age. Females lay from 1 to 10 eggs per clutch and from 0 to 3 clutches annually, with eggs hatching after 67 to 104 days. Populations of G. agassizii have declined rapidly over the last several decades. Habitat throughout the geographic range has experienced major losses, degradation, and fragmentation as a result of urban and agricultural development, livestock grazing, military activities, transportation and utility corridors, high levels of visitor use, vehicle-oriented recreation, and energy development. Disturbed habitats were vulnerable to invading non-native grasses and forbs, creating an unnatural and destructive grass-fire cycle. When consumed by tortoises as their only diet, non-native (and native) grasses are harmful because of limited nutrients. Additionally, subsidized predators (Common Ravens, Coyotes, and dogs), infectious diseases, drought, and vandalism, add to the catastrophic effects of habitat loss and degradation. Tortoise populations have declined rapidly in density, and most populations are below viability, with fewer than 3.9 adults/km2. These declines occurred despite protections afforded by federal and state laws and regulations, ca. 26,000 km2 of federally designated critical habitat units, two Recovery Plans, and efforts to reduce the negative impacts of human activities. As noted by Allison and McLuckie (2018), the negative population trends in most of the critical habitat units suggest that under current conditions G. agassizii is on the path to extinction. Distribution. – USA. Distributed in parts of the southern Great Basin, Mojave, and western Sonoran deserts in southeastern California, southern Nevada, northwestern Arizona, and southwestern Utah, north and west of the Grand Canyon/Colorado River complex, with the exception of a small population east of the Colorado River. Synonymy. – Xerobates agassizii Cooper 1861, Testudo agassizii, Gopherus agassizii, Gopherus polyphemus agassizii, Scaptochelys agassizii, Xerobates lepidocephalus Ottley and Velázques Solis 1989. Subspecies . – None currently recognized. Status. – IUCN 2019 Red List: Vulnerable (VU A1acde+2cde; assessed 1996) ; TFTSG Provisional Red List: Critically Endangered (CR; assessed 2011, 2018); CITES: Appendix II (Testudinidae spp.); US ESA: Threatened.

Arizona, California, Nevada, Utah↗
USGS1976

A geochemical study of oil in metalliferous veins, Idarado Mine, San Juan Mountains, Colorado

A tarry, benzene-soluble material is present in metal-rich veins in the Idarado mine, Ouray County, Colo., in an area not known to have petroleum resources. The material was compared chemically, spectometrically, and chromatographically with oils from four fields in the nearby Paradox basin. Each of these oil fields contains reservoir rocks equivalent to rock units known to extend beneath volcanic rocks near the mine. Carbon and sulfur isotope data and gas chromatographic data indicate a similarity between the oil from the nearby Sierra field and the oil from the mine. Thus, it seems both geologically and chemically possible that oil in the mine originated in Cretaceous sediments. Variations in the composition of oil from the mine and differences between the mine oil and Sierra oil, notably in the distributions of hydrocarbons, are attributed to bacterial degradation.

Colorado↗
USGS2023

Longitudinal analyses of catch-at-age data for reconstructing year-class strength, with an application to lake trout (Salvelinus namaycush) in the main basin of Lake Huron

We investigated using longitudinal models to reconstruct year-class strength (YCS) from catch-at-age data, with an example application to lake trout ( Salvelinus namaycush ) in the main basin of Lake Huron. The best model structure depended on the age range used for model implementation. The YCS trajectory from the full age range (3–30 years) was similar to the trajectory from a narrow age range that approximated the age of recruitment to the fishing gears (5–7 years), but YCS estimates from the full age range included additional variations due to time-dependent selectivity and mortality. When using ages younger or older than the likely ages of recruitment, YCS estimates did not represent recruitment abundances and were also biased by trends in age-specific selectivity and mortality across years. Longitudinal YCS estimates are likely more robust than single-age recruitment indices, which are often subject to interannual changes in catchability and selectivity. Our findings provide guidance for future applications of the longitudinal YCS reconstruction that in turn may inform and supplement more comprehensive research and management programs for understanding fish recruitment dynamics.

Lake Huron↗
USGS2023

Evaluation of Ziram as an oral toxic bait chemical for control of grass carp Ctenopharyngodon idella

The grass carp, Ctenopharyngodon idella , is an invasive species in North America that has been recorded in 45 states with breeding populations in several major river basins. Established populations of grass carp have had cascading, negative effects on aquatic ecosystem structure and function. Oral piscicide baits have been examined as a potential method to manage invasive grass carp. Our goal was to examine the oral toxicity of the dimethyl-dithiocarbamate fungicide, Ziram, to grass carp. Three toxicity experiments used different carriers to deliver single Ziram doses ranging from 0.25 to 250 mg/kg by gavage. No acute mortality was observed when grass carp were gavaged with Ziram at the highest concentrations dissolved in ethanol at 40 mg/kg, suspended in dimethyl sulfoxide (DMSO) at 250 mg/kg, or suspended in polyethylene glycol (PEG) at 150 mg/kg. Ziram exposure through intraperitoneal injection resulted in acute mortality at 150 mg/kg potentially due to increased residence time in the peritoneal cavity and thereby greater opportunity for absorption. These results indicate that Ziram is acutely toxic to grass carp, however, additional research is required to formulate a successful novel grass carp toxicant that can be used to target the invasive species while minimizing effects on non-target fish species.

Management of Biological Invasions↗
USGS2022

Sediment source fingerprinting as an aid to large-scale landscape conservation and restoration: A review for the Mississippi River Basin

Reliable quantitative information on sediment sources to rivers is critical to mitigate contamination and target conservation and restoration actions. However, the determination of the relative importance of sediment sources is complicated at the scale of large river basins by immense variability in erosional processes and sediment sources over space and time, heterogeneity in sediment transport and deposition, and a paucity of sediment monitoring data. Sediment source fingerprinting is an increasingly adopted field-based technique that identifies the nature and relative source contribution of sediment transported in waterways. Notably, sediment source fingerprinting provides information that is independent of other field, modeling, or remotely sensed techniques. However, the diversity in sediment fingerprinting sampling, analytical, and interpretive methods has been recognized as a problem in terms of developing standardized procedures for its application at the scale of large river basins. Accordingly, this review focuses on established sediment source fingerprinting studies conducted within the Mississippi River Basin (MRB), summarizes unique information provided by sediment source fingerprinting that is distinct from traditional monitoring techniques, evaluates consistency and reliability of methodological approaches among MRB studies, and provides prospects for the use of the sediment source fingerprinting technique as an aid to large-scale landscape conservation and restoration under current management frameworks. Most established MRB studies got creditable fingerprinting results and considered near-channel sources as the dominant sediment sources in most cases, while the comparability of their results suffers from a lack of standardization in procedural steps. Findings from MRB studies demonstrate that sediment source fingerprinting is a highly valuable and reliable sediment source assessment approach to assist land and water resource management under current management frameworks, but efforts are still needed to make this technique ready to be used in a more predominant way in large-scale landscape conservation and restoration efforts. We summarized research needs and suggested the best fingerprinting practices for management purposes with the aim of ensuring that this technique is as robust and reliable as it moves forward.

Mississippi River Basin↗
USGS2023

Improving the operational simplified surface energy balance evapotranspiration model using the forcing and normalizing operation

Actual evapotranspiration modeling is providing useful information for researchers and resource managers in agriculture and water resources around the world. The performance of models depends on the accuracy of forcing inputs and model parameters. We developed an improved approach to the parameterization of the Operational Simplified Surface Energy Balance (SSEBop) model using the Forcing and Normalizing Operation (FANO). SSEBop has two key model parameters that define the model boundary conditions. The FANO algorithm computes the wet-bulb boundary condition using a linear FANO Equation relating surface temperature, surface psychrometric constant, and the Normalized Difference Vegetation Index (NDVI). The FANO parameterization was implemented on two computing platforms using Landsat and gridded meteorological datasets: (1) Google Earth Engine (GEE) and (2) Earth Resources Observation and Science (EROS) Center Science Processing Architecture (ESPA). Evaluation was conducted by comparing modeled actual evapotranspiration ( ETa ) estimates with AmeriFlux eddy covariance (EC) and water balance ETa from level-8 Hydrologic Unit Code sub-basins in the conterminous United States. FANO brought substantial improvements in model accuracy and operational implementation. Compared to the earlier version (v0.1.7), SSEBop FANO (v0.2.6) reduced grassland bias from 47% to −2% while maintaining comparable bias for croplands (11% versus −7%) against EC data. A water balance-based ETa bias evaluation showed an overall improvement from 7% to −1%. Climatology versus annual gridded reference evapotranspiration ( ETr ) produced comparable ETa results, justifying the use of climatology ETr for the global SSEBop Landsat ETa that is accessible through the ESPA website. Besides improvements in model accuracy, SSEBop FANO increases the spatiotemporal coverage of ET modeling due to the elimination of high NDVI requirements for model parameterization. Because of the existence of potential biases from forcing inputs and model parameters, continued evaluation and bias corrections are necessary to improve the absolute magnitude of ETa for localized water budget applications.

Remote Sensing↗
USGS1997

Chronology of the episode 54 eruption at Kilauea Volcano, Hawaii, from GOES-9 satellite data

The free availability of GOES satellite data every 15 minutes makes these data an attractive tool for studying short-term changes on cloud-free volcanoes in the Pacific basin. We use cloud-free GOES-9 data to investigate the chronology of the January 1997, episode 54 eruption of Kilauea Volcano, Hawaii. Seventy-six images for this effusive eruption were collected over a 60-hour period and show the opening and shutdown of active fissures, the draining and refilling of the Pu'u 'O'o lava lake, and the cessation of activity at the ocean entry. Copyright 1997 by the American Geophysical Union.

Geophysical Research Letters↗
USGS2007

Modeling aboveground biomass of Tamarix ramosissima in the Arkansas River Basin of Southeastern Colorado, USA

Predictive models of aboveground biomass of nonnative Tamarix ramosissima of various sizes were developed using destructive sampling techniques on 50 individuals and four 100-m2 plots. Each sample was measured for average height (m) of stems and canopy area (m2) prior to cutting, drying, and weighing. Five competing regression models (P < 0.05) were developed to estimate aboveground biomass of T. ramosissima using average height and/or canopy area measurements and were evaluated using Akaike's Information Criterion corrected for small sample size (AICc). Our best model (AICc = -148.69, ??AICc = 0) successfully predicted T. ramosissima aboveground biomass (R2 = 0.97) and used average height and canopy area as predictors. Our 2nd-best model, using the same predictors, was also successful in predicting aboveground biomass (R2 = 0.97, AICc = -131.71, ??AICc = 16.98). A 3rd model demonstrated high correlation between only aboveground biomass and canopy area (R2 = 0.95), while 2 additional models found high correlations between aboveground biomass and average height measurements only (R2 = 0.90 and 0.70, respectively). These models illustrate how simple field measurements, such as height and canopy area, can be used in allometric relationships to accurately predict aboveground biomass of T. ramosissima. Although a correction factor may be necessary for predictions at larger scales, the models presented will prove useful for many research and management initiatives.

Western North American Naturalist↗
USGS2017

Development of a coupled wave-flow-vegetation interaction model

Emergent and submerged vegetation can significantly affect coastal hydrodynamics. However, most deterministic numerical models do not take into account their influence on currents, waves, and turbulence. In this paper, we describe the implementation of a wave-flow-vegetation module into a Coupled-Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system that includes a flow model (ROMS) and a wave model (SWAN), and illustrate various interacting processes using an idealized shallow basin application. The flow model has been modified to include plant posture-dependent three-dimensional drag, in-canopy wave-induced streaming, and production of turbulent kinetic energy and enstrophy to parameterize vertical mixing. The coupling framework has been updated to exchange vegetation-related variables between the flow model and the wave model to account for wave energy dissipation due to vegetation. This study i) demonstrates the validity of the plant posture-dependent drag parameterization against field measurements, ii) shows that the model is capable of reproducing the mean and turbulent flow field in the presence of vegetation as compared to various laboratory experiments, iii) provides insight into the flow-vegetation interaction through an analysis of the terms in the momentum balance, iv) describes the influence of a submerged vegetation patch on tidal currents and waves separately and combined, and v) proposes future directions for research and development.

Computers & Geosciences↗