SEARCH · USGS Science

Results for “Carbon”

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 1,351 records · Page 75Linked to original sources

USGS2014

The carbon cycle and hurricanes in the United States between 1900 and 2011

Hurricanes cause severe impacts on forest ecosystems in the United States. These events can substantially alter the carbon biogeochemical cycle at local to regional scales. We selected all tropical storms and more severe events that made U.S. landfall between 1900 and 2011 and used hurricane best track database, a meteorological model (HURRECON), National Land Cover Database (NLCD), U. S. Department of Agirculture Forest Service biomass dataset, and pre- and post-MODIS data to quantify individual event and annual biomass mortality. Our estimates show an average of 18.2 TgC/yr of live biomass mortality for 1900–2011 in the US with strong spatial and inter-annual variability. Results show Hurricane Camille in 1969 caused the highest aboveground biomass mortality with 59.5 TgC. Similarly 1954 had the highest annual mortality with 68.4 TgC attributed to landfalling hurricanes. The results presented are deemed useful to further investigate historical events, and the methods outlined are potentially beneficial to quantify biomass loss in future events.

Scientific Reports↗

USGS2002

Modelling carbon responses of tundra ecosystems to historical and projected climate: A comparison of a plot- and a global-scale ecosystem model to identify process-based uncertainties

We are developing a process-based modelling approach to investigate how carbon (C) storage of tundra across the entire Arctic will respond to projected climate change. To implement the approach, the processes that are least understood, and thus have the most uncertainty, need to be identified and studied. In this paper, we identified a key uncertainty by comparing the responses of C storage in tussock tundra at one site between the simulations of two models - one a global-scale ecosystem model (Terrestrial Ecosystem Model, TEM) and one a plot-scale ecosystem model (General Ecosystem Model, GEM). The simulations spanned the historical period (1921-94) and the projected period (1995-2100). In the historical period, the model simulations of net primary production (NPP) differed in their sensitivity to variability in climate. However, the long-term changes in C storage were similar in both simulations, because the dynamics of heterotrophic respiration (RH) were similar in both models. In contrast, the responses of C storage in the two model simulations diverged during the projected period. In the GEM simulation for this period, increases in RH tracked increases in NPP, whereas in the TEM simulation increases in RH lagged increases in NPP. We were able to make the long-term C dynamics of the two simulations agree by parameterizing TEM to the fast soil C pools of GEM. We concluded that the differences between the long-term C dynamics of the two simulations lay in modelling the role of the recalcitrant soil C. These differences, which reflect an incomplete understanding of soil processes, lead to quite different projections of the response of pan-Arctic C storage to global change. For example, the reference parameterization of TEM resulted in an estimate of cumulative C storage of 2032 g C m-2 for moist tundra north of 50??N, which was substantially higher than the 463 g C m-2 estimated for a parameterization of fast soil C dynamics. This uncertainty in the depiction of the role of recalcitrant soil C in long-term ecosystem C dynamics resulted from our incomplete understanding of controls over C and N transformations in Arctic soils. Mechanistic studies of these issues are needed to improve our ability to model the response of Arctic ecosystems to global change.

Global Change Biology↗

USGS2002

The role of fire in the boreal carbon budget

To reconcile observations of decomposition rates, carbon inventories, and net primary production (NPP), we estimated long-term averages for C exchange in boreal forests near Thompson, Manitoba. Soil drainage as defined by water table, moss cover, and permafrost dynamics, is the dominant control on direct fire emissions. In upland forests, an average of about 10-30% of annual NPP was likely consumed by fire over the past 6500 years since these landforms and ecosystems were established. This long-term, average fire emission is much larger than has been accounted for in global C cycle models and may forecast an increase in fire activity for this region. While over decadal to century times these boreal forests may be acting as slight net sinks for C from the atmosphere to land, periods of drought and severe fire activity may result in net sources of C from these systems.

Global Change Biology↗

USGS2002

Methane hydrate in the global organic carbon cycle

The global occurrence of methane hydrate in outer continental margins and in polar regions, and the magnitude of the amount of methane sequestered in methane hydrate suggest that methane hydrate is an important component in the global organic carbon cycle. Various versions of this cycle have emphasized the importance of methane hydrate, and in the latest version the role of methane hydrate is considered to be analogous to the workings of an electrical circuit. In this circuit the methane hydrate is a condenser and the consequences of methane hydrate dissociation are depicted as a resistor and inductor, reflecting temperature change and changes in earth surface history. These consequences may have implications for global change including global climate change.

Terra Nova↗

USGS2022

Performance of a carbon dioxide injection system at a navigation lock to control the spread of aquatic invasive species

Natural resource agencies need effective strategies to control the spread of aquatic invasive species (AIS) such as invasive fish, which can expand their range using rivers as hydrological pathways to access new areas. Lock and dam structures within major rivers are prospective locations to deploy techniques, such as carbon dioxide ( CO 2 ) infusion into lock water, that could impede upstream AIS migration without disrupting vessel passage and lock operation. The current pesticide label for CO 2 in the United States allows injections of 100–150 mg/LCO 2 as a behavioral deterrent treatment for invasive carps. This research describes the first operationalizing and testing of a CO 2 injection and manifold distribution system at a 1,548,000-L navigation lock chamber on the Fox River near Kaukauna, Wisconsin, USA. Two chemical distribution manifolds located on the floor and wall of the chamber were independently tested to quantify mixing time, mixing homogeneity, injection efficiency, and operational power requirements under a range of operating parameters. Both manifold configurations were able to meet most performance benchmarks established during previous fish behavior studies. Certain limitations were exhibited and quantified for both manifold configurations in terms of mixing homogeneity and operational power. This research details the design and performance of CO2-to-water infusion systems that could be used to deter the spread of AIS at navigation pinch-points. These results may inform future CO 2 system designs and operating conditions to support natural resource management plans to limit the spread of AIS.

Wisconsin↗

USGS1988

Description and testing of three moisture sensors for measuring surface wetness on carbonate building stones

Three moisture sensors were tested as a means for determining the surface wetness on carbonate building stones exposed to conditions that produce deposition of moisture. A relative-humidity probe, a gypsum-coated circuit grid, and a limestone-block resistor were tested as sensors for determining surface wetness. Sensors were tested under laboratory conditions of constant relative humidity and temperature and also under on-site conditions of variable relative humidity and temperature for eight weeks at Newcomb, NY. Laboratory tests indicated that relative humidity alone did not cause sensors to become saturated with water. However, the rates of drying indicated by the sensors after an initial saturation were inversely related to the relative humidity. On-site testing of the relative-humidity probe and the gypsum-coated ciruit grid indicated that they respond to a diurnal wetting and drying cycle; the limestone-block resistor responded only to rainfall.

Review of Scientific Instruments↗

USGS1969

Oxygen isotope fractionation in divalent metal carbonates

Equilibrium fractionation factors for the distribution of 18 O between alkaline‐earth carbonates and water have been measured over the temperature range 0–500°C. The fractionation factors α"> α α can be represented by the equations CaCO3–H2O, 1000lnα = 2.78(106T−2)− 3.39,"> CaCO 3 – H 2 O , 1000 ln α = 2.78(10 6 T −2 )− 3.39, CaCO3–H2O, 1000lnα = 2.78(106T−2)− 3.39, SrCO3–H2O, 1000lnα = 2.69(106T−2)− 3.74,"> SrCO 3 – H 2 O , 1000 ln α = 2.69(10 6 T −2 )− 3.74, SrCO3–H2O, 1000lnα = 2.69(106T−2)− 3.74, BaCO3–H2O, 1000lnα = 2.57(106T−2)− 4.73."> BaCO 3 – H 2 O , 1000 ln α = 2.57(10 6 T −2 )− 4.73. BaCO3–H2O, 1000lnα = 2.57(106T−2)− 4.73. Measurements on MnCO 3 , CdCO 3 , and PbCO 3 were made at isolated temperatures. A statistical‐mechanical calculation of the isotopic partition function ratios gives reasonably good agreement with experiment. Both cationic size and mass are important in isotopic fractionation, the former predominantly in its effect on the internal vibrations of the anion, the latter in its effect on the lattice vibrations.

Journal of Chemical Physics↗

USGS2007

Toxicity of cobalt-complexed cyanide to Oncorhynchus mykiss , Daphnia magna , and Ceriodaphnia dubia : Potentiation by ultraviolet radiation and attenuation by dissolved organic carbon and adaptive UV tolerance

Background Cobalt cyanide complexes often result when ore is treated with cyanide solutions to extract gold and other metals. These have recently been discovered in low but significant concentrations in effluents from gold leach operations. This study was conducted to determine the potential toxicity of cobalt-cyanide complexes to freshwater organisms and the extent to which ultraviolet radiation (UV) potentiates this toxicity. Tests were also conducted to determine if humic acids or if adaptation to UV influenced sensitivity to the cyanide complexes. Methods Rainbow trout ( Oncorhynchus mykiss ), Daphnia magna , and Ceriodaphnia dubia were exposed to potassium hexacyanocobaltate in the presence and absence of UV radiation, in the presence and absence of humic acids. Cyano-cobalt exposures were also conducted with C. dubia from cultures adapted to elevated UV. Results With an LC 50 concentration of 0.38 mg/L, cyanocobalt was over a 1000 times more toxic to rainbow trout in the presence of UV at a low, environmentally relevant irradiance level (4 μW/cm 2 as UVB) than exposure to this compound in the absence of UV with an LC 50 of 112.9 mg/L. Toxicity was immediately apparent, with mortality occurring within an hour of the onset of exposure at the highest concentration. Fish were unaffected by exposure to UV alone. Weak-acid dissociable cyanide concentrations were observed in irradiated aqueous solutions of cyanocobaltate within hours of UV exposure and persisted in the presence of UV for at least 96 hours, whereas negligible concentrations were observed in the absence of UV. The presence of humic acids significantly diminished cyanocobalt toxicity to D. magna and reduced mortality from UV exposure. Humic acids did not significantly influence survival among C. dubia . C. dubia from UV-adapted populations were less sensitive to metallocyanide compounds than organisms from unadapted populations. Conclusions The results indicate that metallocyanide complexes may pose a hazard to aquatic life through photochemically induced processes. Factors that decrease UV exposure such as dissolved organic carbon or increased pigmentation would diminish toxicity.

Environmental Science and Pollution Research↗

USGS2017

Predation of freshwater fish in environments with elevated carbon dioxide

Carbon dioxide (CO 2 ) in fresh-water environments is poorly understood, yet in marine environments CO 2 can affect fish behaviour, including predator–prey relationships. To examine changes in predator success in elevated CO 2 , we experimented with predatory Micropterus salmoides and Pimephales promelas prey. We used a two-factor fully crossed experimental design; one factor was 4-day (acclimation) CO 2 concentration and the second factor CO 2 concentration during 20-min predation experiments. Both factors had three treatment levels, including ambient partial pressure of CO 2 ( p CO 2 ; 0–1000 μatm), low p CO 2 (4000–5000 μatm) and high p CO 2 (8000–10 000 μatm). Micropterus salmoides was exposed to both factors, whereas P. promelas was not exposed to the acclimation factor. In total, 83 of the 96 P. promelas were consumed ( n = 96 trials) and we saw no discernible effect of CO 2 on predator success or time to predation. Failed strikes and time between failed strikes were too infrequent to model. Compared with marine systems, our findings are unique in that we not only saw no changes in prey capture success with increasing CO 2 , but we also used CO 2 treatments that were substantially higher than those in past experiments. Our work demonstrated a pronounced resiliency of freshwater predators to elevated CO 2 exposure, and a starting point for future work in this area.

Marine and Freshwater Research↗

USGS2016

Carbon dioxide as a tool to deter the movement of invasive bigheaded carps

Nonnative bigheaded carps are established in the Mississippi River and there is substantial concern about their potential entry into the interconnected Laurentian Great Lakes. While electrical barriers currently exist as a preventative measure, there is need for additional control mechanisms to promote barrier security through redundancy. We tested the effectiveness of infused carbon dioxide gas (CO 2 ) as a tool to influence the movement and behavior invasive bigheaded carps, namely Bighead Carp Hypophthalmichthys nobilis and Silver Carp H. molitrix , as well as native Bigmouth Buffalo Ictiobus cyprinellus , Channel Catfish Ictalurus punctatus , Paddlefish Polyodon spathula , and Yellow Perch Perca flavescens in an experimental pond. Individuals were monitored with acoustic telemetry before, during, and after CO 2 addition to the pond. We noted distinct changes in fish behavior following CO 2 addition. Each species except Paddlefish maintained farther distances from the CO 2 infusion manifold relative to controls. Both bigheaded carp species had slower persistence velocities (persistence of a movement in a given direction) following CO 2 infusion and Bighead Carp used a smaller area of the pond immediately after CO 2 addition. Pond pH progressively decreased up to 1.5 units following CO 2 infusion. This work provides evidence that could inform future research to enhance existing control measures used to deter high-risk invasive fishes, such as bigheaded carps.

Transactions of the American Fisheries Society↗

USGS1963

Preliminary results of a study of calcium carbonate saturation of ground water in central Florida

The departure of ground water from equilibrium with calcite is being studied in central Florida . Measurements of pH, temperature, and concentration of bicarbonate made in the field are used with standard laboratory analyses of water samples to calculate an ion activity product (K) for calcium carbonate . The calculated Kiap is compared with the equilibrium constant (Keq) for calcite to determine the departure from equilibrium. The calcium concentration is lowest in the area of the highest piezometric surface. Some of the highest concentrations of bicarbonate are in the area of low calcium . In about half of the area of study , the water is undersaturated with respect to calcite. This indicates that solution of limestone can occur several hundred feet below the water table.

Florida↗

USGS2011

Evaluation of two forms of electroanesthesia and carbon dioxide for short-term anesthesia in walleye

Anesthetics immobilize fish, reducing physical damage and stress during aquaculture practices, stock assessment, and experimental procedures. Currently, only tricaine methanesulfonate (MS-222) is approved for use as an anesthetic for food fish in Canada and the United States; however, MS-222 can only be used with certain fish species, and treated fish must be held for a specified period of time before release into the wild. Two forms of electroanesthesia and carbon dioxide (CO 2 ) were evaluated as anesthetics for adult walleye Sander vitreus to determine their suitability for use before intracoelomic implantation of telemetry transmitters. Walleyes were subjected to one of three treatment groups: constant direct current (CDC), pulsed direct current (PDC), and CO 2 . Fish subjected to these treatments were monitored for induction (where appropriate) and recovery time and whether these forms of anesthesia were conducive to implanting telemetry transmitters, that is, whether they fit a surgery threshold range of 250–350 s. Additionally, all fish were monitored for posttrial survival, and radiographs were taken to determine whether any vertebral damage was associated with the electroanesthesia treatments. Although all anesthetic treatments successfully immobilized fish for enough time to implant a transmitter, PDC electroanesthesia is recommended because of its immediate induction time, quick recovery, high immediate and short-term survival, and lack of evidence of vertebral abnormalities.

North American Journal of Fisheries Management↗

USGS2015

Comparison of electronarcosis and carbon dioxide sedation effects on travel time in adult Chinook and Coho Salmon

The immobilization of fish during handling is crucial in avoiding injury to fish and is thought to reduce handling stress. Chemical sedatives have been a primary choice for fish immobilization. However, most chemical sedatives accumulate in tissues, and often food fishes must be held until accumulations degrade to levels safe for human consumption. Historically, there have been few options for nonchemical sedation . Carbon dioxide (CO 2 ) has been widely used for decades as a sedative, and while it does not require a degradation period, it does have drawbacks. The use of electronarcosis is another nonchemical option that does not require degradation time . However, little is known about the latent and delayed effects on migration rates of adult salmonids that have been immobilized with electricity. We compared the travel times of adult Chinook Salmon Oncorhynchus tshawytscha and Coho Salmon O. kisutch through a fishway at river kilometer (rkm) 4, and to rkm 16 and rkm 32 after being immobilized with either CO 2 or electronarcosis . Travel times of fish treated with either CO 2 or electronarcosis were similar within species. Because of the nearly instantaneous induction of and recovery from electronarcosis , we recommend it as an alternative to CO 2 for handling large adult salmonids.

Washington↗

USGS2017

Using carbon dioxide in fisheries and aquatic invasive species management

To restore native fish populations, fisheries programs often depend on active removal of aquatic invasive species. Chemical removal can be an effective method of eliminating aquatic invasive species, but chemicals can induce mortality in nontarget organisms and persist in the environment. Carbon dioxide (CO 2 ) is an emerging alternative to traditional chemical control agents because it has been demonstrated to be toxic to fish, but is naturally occurring and readily neutralized. In addition, CO 2 is a commercially available gas, is highly soluble, and has high absorption efficiency. When these characteristics are paired with advances in modern, large-scale gas delivery technologies, opportunities to use CO 2 in natural or artificial (e.g., canals) waters to manage fish become increasingly feasible. Our objective is to describe the history of CO 2 use in fisheries and outline potential future applications of CO 2 to suppress and manipulate aquatic species in field and aquaculture settings.

Fisheries↗

USGS2025

Carbon dioxide infusion reduces invasive mussel biofouling (quagga mussel; Dreissena rostriformis bugensis) in raw water systems

The efficacy of carbon dioxide (CO 2 ) to reduce biofouling by quagga mussels ( Dreissena rostriformis bugensis ) in raw water systems was investigated. Experiments were conducted in a mobile laboratory located at Bureau of Reclamation Davis Dam Hydropower Facility and supplied with raw water from Lake Mohave, a reservoir of the Colorado River, USA. Incoming water was split between five chambers, each infused with CO 2 at a different rate. Raw reservoir water containing quagga larvae (veligers) was mixed with CO 2 chamber outflows and delivered to tanks containing settlement plates. Two experiments were conducted. Experiment 1 tested continuous infusion at target concentrations of 30, 45, 60, 75, and 100 mg L -1 dCO 2 (dissolved CO 2 ). Experiment 2 evaluated intermittent infusion schedules: 24 h on/off with 50, 75, and 100 mg L -1 dCO 2 and 24 h once/week with 100 mg L -1 dCO 2 . In Experiment 1, the percent settlement decreased with mean CO 2 concentration, ranging from 5.0% to < 0.1% in 28.7 and 92.2 mg L -1 dCO 2 , respectively. In Experiment 2, the efficacy of 24 h on/off at dCO 2 > 72.2 mg L -1 was similar to continuous treatment. The least effective treatment was 24 h once weekly at 95 mg L -1 dCO 2 . These results demonstrate that CO 2 treatment may reduce mussel biofouling in raw water systems.

Arizona, Nevada↗

USGS2024

Role of edaphic, hydrologic, and land cover variables in determining dissolved organic carbon in Missouri (USA) reservoirs and streams

In Missouri, distinct geophysical gradients influence statewide patterns in water quality. Here, we quantify the spatiotemporal variability of dissolved organic carbon (DOC) in reservoirs and streams and the edaphic, hydrologic, and land cover variables that account for cross-system variation. Datasets included statewide inventories collected over decades and studies with greater temporal resolution ( n = >6350 DOC measurements). Among reservoirs, the smallest DOC concentration was measured in a spring-fed system within a forested watershed, and the largest was where agricultural biosolids were applied to the land (range 1.0–15.9 mg/L, overall mean 5.8 mg/L). Reservoir values increased from the southern forested Highlands (mean 4.7 mg/L) to the northern agricultural Plains (mean 7.0 mg/L). Stream DOC was similar to reservoir values (overall mean in streams 6.3 mg/L; Highlands mean 4.0 mg/L; Plains mean 6.6 mg/L), despite differences in study design and collection period. Reservoir DOC increased in spring, indicative of allochthonous loading, with small autochthonous additions during a broad summer peak. Temporal variability in DOC was low relative to macronutrients and chlorophyll in both reservoirs and streams, indicating DOC may be a sensitive and readily detected indicator of temporal change in these systems. In regression analyses, watershed features accounted for more than 60% of overall cross-system variability in DOC in both reservoirs and streams. Driver-response relations, however, differed between regions. This analysis extends our understanding of environmental influences on surface water chemistry in Missouri and indicates DOC is nearly as predictable as macronutrients using landscape-level features.

Missouri↗

USGS2021

Shrub influence on soil carbon and nitrogen in a semi-arid grassland is mediated by precipitation and largely insensitive to livestock grazing

Dryland (arid and semi-arid) ecosystems globally provide more than half of livestock production and store roughly one-third of soil organic carbon (SOC). Biogeochemical pools are changing due to shrub encroachment, livestock grazing, and climate change. We assessed how vegetation microsite, grazing, and precipitation interacted to affect SOC and total nitrogen (TN) at a site with long-term grazing manipulations and well-described patterns of shrub encroachment across elevation and mean annual precipitation (MAP) gradients. We analyzed SOC and TN in the context of vegetation cover at ungrazed locations within livestock exclosures, high-intensity grazing locations near water sources, and moderate-intensity grazing locations away from water. SOC was enhanced by MAP ( p < 0.0001), but grazing intensity had little effect regardless of MAP ( p = 0.12). Shrubs enhanced SOC (300–1279 g C m −2 ) and TN (27–122 g N m −2 ), except at high MAP where the contribution or stabilization of shrub inputs relative to grassland inputs was likely diminished. Cover of perennial herbaceous plants and litter were significant predictors of SOC ( r 2 = 0.63 and 0.34, respectively) and TN ( r 2 = 0.64 and 0.30, respectively). Our results suggest that continued shrub encroachment in drylands can increase SOC storage when grass production remains high, although this response may saturate with higher MAP. In contrast, grazing – at least at the intensities of our sites – has a lesser effect. These effects underscore the need to understand how future climate and grazing may interact to influence dryland biogeochemical cycling.

Arid Land Research and Management↗

USGS2017

Light climate and dissolved organic carbon concentration influence species-specific changes in fish zooplanktivory

Dissolved organic carbon (DOC) in lakes reduces light penetration and limits fish production in low nutrient lakes, reportedly via reduced primary and secondary production. Alternatively, DOC and light reductions could influence fish by altering their visual feeding. Previous studies report mixed effects of DOC on feeding rates of zooplanktivorous fish, but most investigators tested effects of a single concentration of DOC against clear-water, turbid, or algal treatments. We used a controlled laboratory study to quantify the effects of a DOC gradient (3–19 mg L −1 ) on average light climate and the zooplankton feeding rate of 3 common, north temperate fishes. Light availability, which was inversely related to DOC concentration, had a positive and linear effect on zooplankton consumption by juvenile largemouth bass ( Micropterus salmoides ) and bluegill ( Lepomis macrochirus ), explaining 22% and 28% of the variation in consumption, respectively. By contrast, zooplankton feeding rates by fathead minnow ( Pimephales promelas ) were best predicted by a nonlinear, negative influence of light ( R 2 = 0.13). In bluegill feeding trials we found a general trend for positive selection of larger zooplankton (Cladocera and Chaoboridae); however, the light climate did not influence the selection of prey type. Largemouth bass selected for larger-bodied zooplankton, with weak evidence that selectivity for large Cladocera changed from negative to neutral selection based on electivity values across the light gradient. Our results suggest that the effect of DOC on the light climate of lakes may directly influence fish zooplanktivory and that this influence may vary among fish species.

Inland Waters↗