Research at hubbard brook showed that stream nitrate concentrations

X_1 The findings were somewhat of a surprise because denitrification has been so difficult to measure at Hubbard Brook even though deposition and export relationships suggested that denitrification may have been a factor in the decline of nitrate concentrations observed in streamwater. The paper significance statement and abstract are below.A synthesis of the biogeochemistry of Ca was done during 1963-1992in reference and human-manipulated forest ecosystems of the Hubbard BrookExperimental Forest (HBEF), NH. Results showed that there has been a markeddecline in concentration and input of Ca in bulk precipitation, an overalldecline in concentration and output of Ca in stream water, and markeddepletion of Ca in soils of the HBEF ..."[T]his intimate history of research at Hubbard Brook stands as testimony to the rich rewards of sustained government investment in support of ecological research. Kudos to the authors and all who have been involved in this grand venture, which we hope will continue well into the future."—Martin J...The second image, comparatively, shows those same blood cells adjusted back to their normal state following treatment. In this case, a young man received a Wuhan Flu jab and 15 days later developed what is shown in the first image: serious blood clotting even more disturbing than the images above.The Hubbard Brook research program has grown steadily since these initial experiments. The National Science Foundation began funding the work in the 1960s, and gave the program an additional boost in 1987 when it included Hubbard Brook in its Long Term Ecological Research (LTER) network (read sidebar ).(A) Nitrate concentrations in stream water from the three experimentally deforested watersheds (W2, W4, and W5). These data are normalized to the [NO 3-] in-stream export from W6, the reference watershed, to more clearly show the effects of the cutting events without including the variation in export common to all six watersheds.(B) Patterns of NO 3-export over the same time period for W1 and ...during the winter-except at Hubbard Brook and East Branch, where samples were collected weekly. Specific conductance was measured in the field. Laboratory measurements included pH, concentrations of nitrate, calcium, magnesium, sodium, and potassium. Concentrations of ammonium, sulfate, and chloride were measured but not in all streams. The methodsProgress 10/01/03 to 09/30/04 Outputs Progress is reported for three elements: (A) The 3,160 hectare Hubbard Brook Experimental Forest (HBEF) in New Hampshire has been a prime area of research on forest and stream ecosystems since its establishment by the USDA Forest Service in 1955. Streamflow and precipitation have been measured continuously ...ABSTRACT The Hubbard Brook (HBR) Experimental Forest LTER project began in 1988, drawing on a history of forest ecosystem research that began in the 1950s, and has the continuing overall goal of improving understanding of the structure and function of Northern Forest ecosystems and their responses to environmental change and disturbance.At Hubbard Brook, no .__ significant increase in nitrate concentration in stream water was observed c_. during 1970, the year of peak insect defoliation. HoGvex-Holmes and Sturges (1975) have shown that during the years when Heterocampu was in outbreak phase, many birds concentrated on.(A) Nitrate concentrations in stream water from the three experimentally deforested watersheds (W2, W4, and W5). These data are normalized to the [NO 3-] in-stream export from W6, the reference watershed, to more clearly show the effects of the cutting events without including the variation in export common to all six watersheds.(B) Patterns of NO 3-export over the same time period for W1 and ...Online Book: A Synthesis of Scientific Research at Hubbard Brook. To examine whether stream nitrogen concentrations in forested reference catchments have changed We found both increasing and decreasing trends in monthly flow-weighted stream nitrate and ammonium concentrations.May 12, 2004 · the water year the same as that used for Hubbard Brook Experimental Watershed, 1 June to 31 May (Likens and Bormann, 1995). Hubbard Brook has a similar climate and hydrological properties as the uplands at the Archer Creek watershed, but a much longer record of stream flow (Scott, 1987; Likens and Bormann, 1995). "Long-term trends in soil solution and stream water chemistry at the Hubbard Brook Experimental Forest: relationship with landscape position." Biogeochemistry , v.68 , 2004 , p.51 Whitall, D., M. Castro and C. Driscoll.The forest is part of the National Science Foundation's Long-Term Ecological Research program. At sites throughout the forest, the research team measured the presence of nitrate, a form of nitrogen that is highly mobile and reactive in the environment, and determined whether the nitrate was a result of atmospheric deposition or nitrification.Stream water nitrate-N concentrations during floods were consistently 0.2-0.5 mg/L higher in 2002 than during 2001, suggesting greater over-winter accumulation of soil nitrate during the drier year. This result is consistent with higher mean nitrate-N concentrations in soil water of the riparian zone in 2002 (3.1 mg/L) than in 2001 (0.56 mg/ L). 2008] or land management changes [Yallop and Clutterbuck, 2009; Holden et al., 2012]. Hubbard Brook, the site of our current study, is an outlier by defying the trends of increasing DOC concentrations in surface waters. During the years 1982-2000, stream water DOC declined at Hubbard Brook, coincident with88 Chapter 5: Nitrate processing in the stream sediment of an urbanized watershed……..122 Urban streams and rivers tend to have higher concentrations of dissolved inorganic nitrogen (NH4+ More recent research has shown that nutrient retention and denitrification are promoted when riparian...nitrate concentrations were below 0.5 mg/l for both harvested and control watersheds. Exceptions were in the red alder (Alnus rubra) and Douglas-fir (Pseudotsuga menzesii) forests in Or-egon, where equally high levels of nitrate existed in the control and treatment watersheds, and in the hardwood forests of Hubbard Brook. All vegetation on Watershed 2 of the Hubbard Brook Experimental Forest was cut during November and December of 1965, and vegetation regrowth was inhibited for two years by periodic application of herbicides. Annual stream-flow was increased 39% the first year and 28% the second year.measurements of stream discharge. For the BNA, stream samples were collected at intervals ranging from 2 to 4 •reeks, and samples were analyzed for NO 3' and NH4 + concentrations. Because of restrictions on research activities that can be conducted at Research Natural Areas, a stream gauging station has not been established for the BNA.the water year the same as that used for Hubbard Brook Experimental Watershed, 1 June to 31 May (Likens and Bormann, 1995). Hubbard Brook has a similar climate and hydrological properties as the uplands at the Archer Creek watershed, but a much longer record of stream flow (Scott, 1987; Likens and Bormann, 1995).[1] This study uses time series analysis to examine long‐term stream water nitrate concentration records from a pair of forested catchments at the Coweeta Hydrologic Laboratory, North Carolina, USA. Monthly average concentrations were available from 1970 through 1997 for two forested catchments, one of which was clear‐felled in 1977 and the other maintained as a control."[T]his intimate history of research at Hubbard Brook stands as testimony to the rich rewards of sustained government investment in support of ecological research. Kudos to the authors and all who have been involved in this grand venture, which we hope will continue well into the future."—Martin J...Hubbard Brook, the site of our current study, is an outlier by defying the trends of increasing DOC concentrations in surface waters. During the years 1982-2000, stream water DOC declined at Hubbard Brook, coincident with decreased DOC leaching in soil water [Palmer et al., 2004].The calculations showed that precipitation provides most of the 30-50 kilograms of sulfate per hectare carried annually by the streams and that inputs exceed outflows of ammonium and of nitrate. Maximum effluent bicarbonate and silica concentrations vary directly with each other and inversely with aluminum.Progress 10/01/09 to 09/30/10 Outputs OUTPUTS: The LTER project at Hubbard Brook Experimental Forest is designed to address basic and applied problems in forest ecosystem biology with an emphasis on biogeochemical cycling and the role of natural and anthropogenic disturbance in shaping ecosystem dynamics. During the past year we were successful in obtaining six years of renewed funding to ...Concentration of dissolved solutes and suspended sediments compared to stream discharge have been shown to be a useful and rather straightforward approach to evaluating For an example on hysteresis, assume that stream nitrate levels are higher on the rising as compared to the failing limb.Hubbard Brook, NH 3. Sleepers River, VT 4. Plum Island, MA 5. Biscuit Brook, NY (part of the New York City, drinking watersheds) ... Results from a previous LTER working group show ... be an important control on stream nitrate concentrations (Biron et al., 1999) because it sets the temporal limit on the amount of nitrate produced viaWatershed 6, Hubbard Brook Experimental Forest, NH HBEF 43°56′N 13.1 490-775 525 1992-1993 6 71°45′W Arbutus Watershed, Huntington Forest, NY HF 43°59′N 309 513-701 358 1992-1993 10 74°14′W Biscuit Brook, NY CS 41°59′N 960 628-1128 570 1985-1986 11 74°25′W FIGURE 1. Monthly nitrate concentrations at the base of watershedOur work is supported by the National Science Foundation, the USDA Forest Service and other government and private funders. Any opinions, findings, conclusions, and recommendation nitrate concentrations were below 0.5 mg/l for both harvested and control watersheds. Exceptions were in the red alder (Alnus rubra) and Douglas-fir (Pseudotsuga menzesii) forests in Or-egon, where equally high levels of nitrate existed in the control and treatment watersheds, and in the hardwood forests of Hubbard Brook. al. 1981) and Bear Brook (Lawrence et al. 1986). The stream channel in Cascade Brook contains extensive areas of exposed bedrock, and appears to have sub-stantially fewer organic debris dams than other streams in the Hubbard Brook Valley. Mirror Lake is a small softwater lake near the mouth of the Hubbard Brook Valley (Fig. 1; Likens 1985).There is a strong relationship between stream nitrate concentrations before and after disturbance, but there are four strongly divergent outliers (all four outside the 95th percentile confidence limits) (Fig. 2).The first of these, which is well above the trend line, is for the classic study at the Hubbard Brook Experimental Forest (HBEF) involving catchment clear-cut harvesting of an entire ...high nitrate concentrations alleviates demand for ammonium, which is a pattern observed at Hubbard Brook, NH. The production/respiration ratios were strongly related to the ratio of nitrate uptake velocity and ammonium uptake velocity (Fig 3). This pattern shows that streams with high production (i.e.Central to the exposé is Brook Jackson, who, for two weeks, served as regional director at Ventavia Research Group, the company contracted to assist with the pivotal trial. She provided The BMJ with dozens of internal company documents, photos, audio recordings, and emails supporting her concerns.Changes to rates of biogeochemical transformations during autumn base flow explained the low nitrate concentrations; in‐stream transformations retained up to 72% of the nitrate that entered a stream reach. A decrease of in‐stream nitrification coupled with heterotrophic nitrate cycling were primary factors in the seasonal nitrate decline.during the winter-except at Hubbard Brook and East Branch, where samples were collected weekly. Specific conductance was measured in the field. Laboratory measurements included pH, concentrations of nitrate, calcium, magnesium, sodium, and potassium. Concentrations of ammonium, sulfate, and chloride were measured but not in all streams. The methodsOne of the Hubbard Brook watersheds (W2) was clear-felled in 1965-66 and herbicided for 3 years to prevent any regrowth. Following this, levels of nitrate in stream water increased to 7-10 times Figure 2.12 shows that the popular belief that most of the nutrients in a tropical rain forest are in the...The frequencies of chemical concentrations in streams in small, forested watersheds showed more streams with higher NO3− concentrations than the streams used in national monitoring programs of larger, mostly forested watersheds. At a local scale, no trend in nitrate concentration with stream order or basin size was consistent across studies.The effects of a whole-watershed calcium addition on the chemistry of stream storm events at the Hubbard Brook Experimental Forest in NH, USA Sci Total Environ . 2009 Oct 1;407(20):5392-401. doi: 10.1016/j.scitotenv.2009.06.030. "Long-term trends in soil solution and stream water chemistry at the Hubbard Brook Experimental Forest: relationship with landscape position." Biogeochemistry , v.68 , 2004 , p.51 Whitall, D., M. Castro and C. Driscoll.Fig. 1. (A) Nitrate concentrations in stream water from the three experimentally deforested watersheds (W2, W4, and W5).These data are normalized to the [NO 3-] in-stream export from W6, the reference watershed, to more clearly show the effects of the cutting events without including the variation in export common to all six watersheds.(B) Patterns of NO 3-export over the same time period for ...Some major biogeochemical findings of the Hubbard Brook Ecosystem Study are discussed briefly, including acid rain, and some biogeochemical research questions, opportunities, and challenges for the future are identified, including a recent whole‐watershed addition of calcium silicate, weathering processes, and long‐term trends in stream ...Oct 06, 2016 · Nitrate concentrations in precipitation did not show any significant trend between 1981 and 2002, but after the implementation of the NO x Budget Trading Program (NBP; established under the NO x State Implementation Plan [SIP] Call Program in 2003; Burtraw and Szambelan 2009) significantly (P < 0.001) decreased at a rate of 0.3 μmol c ·L −1 ... the water year the same as that used for Hubbard Brook Experimental Watershed, 1 June to 31 May (Likens and Bormann, 1995). Hubbard Brook has a similar climate and hydrological properties as the uplands at the Archer Creek watershed, but a much longer record of stream flow (Scott, 1987; Likens and Bormann, 1995).We measured stream characteristics and nitrate uptake velocities before and after wood manipulation experiments. conducted at Hubbard Brook Experimental Forest, NH, and the Sleepers River watershed, VT. The mean size of stream substrates and the amount of rife habitat increased following...One of the Hubbard Brook watersheds (W2) was clear-felled in 1965-66 and herbicided for 3 years to prevent any regrowth. Following this, levels of nitrate in stream water increased to 7-10 times Figure 2.12 shows that the popular belief that most of the nutrients in a tropical rain forest are in the...Nitrate was exported in highest concentrations from Watershed 7 during each year, presumably the result of (2005) showed that the deposition of SO42- and NO3- are strongly related to the emissions of Hubbard Brook, the site of this dissertation research, has been shown to be somewhat of an Stream water DOC concentration has shown a long-term decline at Hubbard Brook, apparently...Changes to rates of biogeochemical transformations during autumn base flow explained the low nitrate concentrations; in‐stream transformations retained up to 72% of the nitrate that entered a stream reach. A decrease of in‐stream nitrification coupled with heterotrophic nitrate cycling were primary factors in the seasonal nitrate decline.A framework is developed for characterizing the temporal inequality of stream discharge and solute loads to receiving waters using Lorenz diagrams and the associated Gini coefficient, G. These descriptors are used to illustrate a broad range of observed flow variability with a synthesis of multidecadal flow data from 22 rivers in Florida.Journal of Geophysical Research: Biogeosciences observations of watershed stream nitrate export at the Hubbard Brook Experimental Forest (HBEF), NH have shown that declines began in the 1960s, well before NOx emission declines associated with the Clean Air Act, and continue today (Groffman et al., 2018). Nov 03, 2021 · Bormann, F. H. & Likens, G. E. Pattern and process in a forested ecosystem: disturbance, development and the steady state based on the Hubbard Brook ecosystem study. (Springer Science & Business ... A framework is developed for characterizing the temporal inequality of stream discharge and solute loads to receiving waters using Lorenz diagrams and the associated Gini coefficient, G. These descriptors are used to illustrate a broad range of observed flow variability with a synthesis of multidecadal flow data from 22 rivers in Florida.This reconstruction showed acid rain peaking at HBEF in the late 1960s-early 1970s near the beginning of the Hubbard Brook Ecosystem Study (HBES). The long-term, parabolic arc in acid inputs to HBEF generated a corresponding arc in the ionic strength of stream water, with acid inputs generating increased losses of H + and soil base cations ...Figure 1. Nitrate concentrations at Hubbard Brook Experimental Forest (HBEF), Watershed 5, and Shenandoah National Park (SHEN), Paine Run. Note the separate y axis for the HBEF and SHEN data sets. Recovery of nitrate levels to baseline conditions took 3-4 years at Watershed 5 but has taken over a decade at Paine Run.Nutrient Losses - Hubbard Brook Cut Uncut Nitrate Calcium Magnesium Potassium Sodium 142 kg/ha/yr 90 18 36 17 Nitrate Calcium Magnesium Potassium Sodium No loss 9.2 kg/ha/yr 2.6 1.6 7.0 (3) The hydrogen ion content increased, from average stream pH 5-1 "to 4.3* (4) Stream water temperatures increased.At the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, for example, we know that current concentrations of nitrate in watershed streams are the lowest in 46 y of measurement and that ecosystem nitrate losses have decreased by >90% over this time (Fig. 1A).A framework is developed for characterizing the temporal inequality of stream discharge and solute loads to receiving waters using Lorenz diagrams and the associated Gini coefficient, G. These descriptors are used to illustrate a broad range of observed flow variability with a synthesis of multidecadal flow data from 22 rivers in Florida.At Hubbard Brook, no .__ significant increase in nitrate concentration in stream water was observed c_. during 1970, the year of peak insect defoliation. HoGvex-Holmes and Sturges (1975) have shown that during the years when Heterocampu was in outbreak phase, many birds concentrated on.Results showed that removing OA from our simulations also increased modelled streamwater Driscoll, C. T.: Longitudinal Stream Chemistry at the Hubbard Brook Experimental Forest Likens, G.: Chemistry of Bulk Precipitation at Hubbard Brook Experimental Forest, Watershed 6...Ammonium, urea, and nitrate were added to Bear Brook, a second and third order stream in the Hubbard Brook Experimental Forest, New Hampshire. Removal of ammonium and urea during downstream transport coincided with the release of nitrate. Nitrate removal did not occur when it was added alone or with dissolved organic carbon. Laboratory experiments showed that coarse particulate organic ...Research obtained by a group of scientists shows the COVID vaccine spike protein can travel from the injection site and accumulate in organs and tissues including the spleen, bone marrow, the liver, adrenal glands and in "quite high concentrations" in the ovaries.streams of the Hubbard Brook Experimental Forest (HBEF) vary widely in their N03- concentrations during the growing season. This variation may be caused by differences in the terrestrial systems they drain (for example, varying forest age or composition, hydrology, soil organic matter content, and so on) Central to the exposé is Brook Jackson, who, for two weeks, served as regional director at Ventavia Research Group, the company contracted to assist with the pivotal trial. She provided The BMJ with dozens of internal company documents, photos, audio recordings, and emails supporting her concerns.The Hubbard Brook research program has grown steadily since these initial experiments. The National Science Foundation began funding the work in the 1960s, and gave the program an additional boost in 1987 when it included Hubbard Brook in its Long Term Ecological Research (LTER) network (read sidebar ).The U.S. Department of Energy's Office of Scientific and Technical InformationA synthesis of the biogeochemistry of K was conducted during 1963-1992 in the reference and human-manipulated watershed-ecosystems of the Hubbard Brook Experimental Forest (HBEF), NH. Results showed that during the first two years of the study (1963-65), which coincided with a drought period, the reference watershed was a net sink for atmospheric inputs of K. During the remaining years ...Nitrate concentrations have been measured weekly in the gauged streams that drain into the main stem of Hubbard Brook in the HBEF since the mid-sixties (Likens & Bormann 1995; Buso et al. 2000; Fig. 1). Six south-facing watersheds (W1-W6) were included in this study, along with the main stem of Hubbard Brook, a fifth order stream. Two of the ...We quantified hydrologic source areas and flow paths, acid‐base and aluminum chemistry, dissolved organic carbon dynamics, and mercury mobilization during snowmelt at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA. Here we show (1) episodic acidification during snowmelt at the HBEF is controlled by multiple mechanisms (base cation dilution, nitrate and aluminum acidity, and ...and forest succession within catchments. At the Hubbard Brook Experimental Forest in New Hampshire, stream nitrate concentrations have been declining in recent decades after increasing from 1963 into the 1970s (Likens and Bormann 1995, Campbell et al 2007). These trends in stream nitrate at Hubbard Brook have not been explained by changes inWe quantified hydrologic source areas and flow paths, acid‐base and aluminum chemistry, dissolved organic carbon dynamics, and mercury mobilization during snowmelt at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA. Here we show (1) episodic acidification during snowmelt at the HBEF is controlled by multiple mechanisms (base cation dilution, nitrate and aluminum acidity, and ...the y axis - peak nitrate concentrations back in the 1960s exceeded 0.4 mg N/L while in WY2019 they were more than 5X lower (always below 0.07 mg N /L. Second, note that in the earlier year, nitrate concentrations stayed higher in the summer (for the last two decades we usually are unable to detect nitrate in the stream during the summer unlessChanges to rates of biogeochemical transformations during autumn base flow explained the low nitrate concentrations; in‐stream transformations retained up to 72% of the nitrate that entered a stream reach. A decrease of in‐stream nitrification coupled with heterotrophic nitrate cycling were primary factors in the seasonal nitrate decline.Nutrient Losses - Hubbard Brook Cut Uncut Nitrate Calcium Magnesium Potassium Sodium 142 kg/ha/yr 90 18 36 17 Nitrate Calcium Magnesium Potassium Sodium No loss 9.2 kg/ha/yr 2.6 1.6 7.0 (3) The hydrogen ion content increased, from average stream pH 5-1 "to 4.3* (4) Stream water temperatures increased.the y axis - peak nitrate concentrations back in the 1960s exceeded 0.4 mg N/L while in WY2019 they were more than 5X lower (always below 0.07 mg N /L. Second, note that in the earlier year, nitrate concentrations stayed higher in the summer (for the last two decades we usually are unable to detect nitrate in the stream during the summer unlessOnline Book: A Synthesis of Scientific Research at Hubbard Brook. To examine whether stream nitrogen concentrations in forested reference catchments have changed We found both increasing and decreasing trends in monthly flow-weighted stream nitrate and ammonium concentrations.Temporal inequality in catchment discharge and solute export Temporal inequality in catchment discharge and solute export Jawitz, James W.; Mitchell, Jennifer 2011-10-01 00:00:00 A framework is developed for characterizing the temporal inequality of stream discharge and solute loads to receiving waters using Lorenz diagrams and the associated Gini coefficient, G.Nitrate concentrations have been measured weekly in the gauged streams that drain into the main stem of Hubbard Brook in the HBEF since the mid-sixties (Likens & Bormann 1995; Buso et al. 2000; Fig. 1). Six south-facing watersheds (W1-W6) were included in this study, along with the main stem of Hubbard Brook, a fifth order stream. Two of the ...10 of 18 W01511 DEMERS ET AL.: EPISODIC ACIDIFICATION AND MERCURY MOBILIZATION W01511 Figure 4. Snowpack, discharge, and stream concentrations of major solutes that regulate the acid-base status of W6 during snowmelt at the Hubbard Brook Experimental Forest.Concentrations of nitrate in stream water throughout the world are reported to be elevated relative to natural background levels. This enrichment is commonly attributed to anthropogenic activities ...Progress 10/01/09 to 09/30/10 Outputs OUTPUTS: The LTER project at Hubbard Brook Experimental Forest is designed to address basic and applied problems in forest ecosystem biology with an emphasis on biogeochemical cycling and the role of natural and anthropogenic disturbance in shaping ecosystem dynamics. During the past year we were successful in obtaining six years of renewed funding to ...Research was conducted along a first order segment of a stream draining Watershed 5 (hereafter referred to as the whole-tree harvested stream-WTH) and along first (draining Watershed 6) and second order segments of Bear Brook (the CONTROL stream), New Hampshire, U.S.A. All sites are found within the Hubbard Brook Experimental Forest (43?56'N ...Export exceeded input of most nutrients for 2 reasons. First, the absence of evapotranspiration lead to a 40% increase in stream discharge and accelerated leaching of soil nutrients. The second phenomenon was decoupling of decomposition and plant nutrient uptake in the watersheds. Soil ammonium concentrations increased mainly due to ...Why is Hubbard Brook valuable as a study area? Hubbard Brook is a valuable study area because it is an ideal watershed area. Researchers using the Hubbard Brook was able to determine that when trees are no longer there to take up the soil nitrate, it leaches out of the soil and ends up in the stream which drains into the watershed.and forest succession within catchments. At the Hubbard Brook Experimental Forest in New Hampshire, stream nitrate concentrations have been declining in recent decades after increasing from 1963 into the 1970s (Likens and Bormann 1995, Campbell et al 2007). These trends in stream nitrate at Hubbard Brook have not been explained by changes in One striking result of the Hubbard Brook Experiment on watershed 2 was the large increase in nitrate in stream water exiting the watershed. Use a simple drawing to show the source of this nitrogen (e.g. where did it mainly come from?) and how this nitrogen is converted into nitrate which ends up in the stream water.Aber et al. (2002), using the and (4) How large is the uncertainty in predicted ozone PnET-CN model, simulated an increase in inorganic nitrogen effects? loss of about 0.05 gN/m2 per year after the 1960s due to am- bient ozone concentrations at the Hubbard Brook watershed in New Hampshire, USA.Ammonium, urea, and nitrate were added to Bear Brook, a second and third order stream in the Hubbard Brook Experimental Forest, New Hampshire. Removal of ammonium and urea during downstream transport coincided with the release of nitrate. Nitrate removal did not occur when it was added alone or with dissolved organic carbon. Laboratory experiments showed that coarse particulate organic ...after 2000 were driven by the storm damage and that stream nitrate effects were movement of Ca added to the Soil solution Nitrogen concentrations in foliage showed no chemistry in the Oa horizon was affected by the coherent Effects of nitrogen 0315211, Hubbard Brook Long Term Research in additions on annual nitrous oxide fluxes from Soil chemistry and istry of calcium at Hubbard Brook.Stream water during the snowmelt period has had very similar gains in ANC as for the overall time series (0.69 and 0.78 μeq l-1 yr-1, respectively). Additionally, we found that for both the overall stream chemistry record and for the snowmelt period, the trends showed similar increases in pH, decreases in sulfate, and decreases in nitrate. TheWhy is Hubbard Brook valuable as a study area? Hubbard Brook is a valuable study area because it is an ideal watershed area. Researchers using the Hubbard Brook was able to determine that when trees are no longer there to take up the soil nitrate, it leaches out of the soil and ends up in the stream which drains into the watershed.clearcut leads to an increased stream-nitrate concentration, which has been documented in several study sites (e.g., Plynlimon in the UK, Hubbard Brook and Coweeta Experimental Forests in the USA [18-20]). The duration of nitrate run-off and the long-term consequences have received lessSome major biogeochemical findings of the Hubbard Brook Ecosystem Study are discussed briefly, including acid rain, and some biogeochemical research questions, opportunities, and challenges for the future are identified, including a recent whole‐watershed addition of calcium silicate, weathering processes, and long‐term trends in stream ...after 2000 were driven by the storm damage and that stream nitrate effects were movement of Ca added to the Soil solution Nitrogen concentrations in foliage showed no chemistry in the Oa horizon was affected by the coherent Effects of nitrogen 0315211, Hubbard Brook Long Term Research in additions on annual nitrous oxide fluxes from Soil chemistry and istry of calcium at Hubbard Brook.Nevertheless, concentrations were three times lower than those recorded in the "herbicide without biomass removal" treatment in the Hubbard Brook Experiment (Likens et al. 1978 ), underscoring the important role of undisturbed residual and regenerating vegetation for nitrate retention (Pardo et al .Nov 03, 2021 · Bormann, F. H. & Likens, G. E. Pattern and process in a forested ecosystem: disturbance, development and the steady state based on the Hubbard Brook ecosystem study. (Springer Science & Business ... Stream export of nitrogen (N) as nitrate (NO 3 − ; the most mobile form of N) from forest ecosystems is thought to be controlled largely by plant uptake of inorganic N, such that reduced demand for plant N during the non-growing season and following disturbances results in increased stream NO 3 − export. The roles of microbes and soils in ecosystem N retention are less clear, but are the ...Hubbard Brook. The Story of a Forest Ecosystem. Richard T. Holmes and Gene E. Likens. Richard T. Holmes and Gene E. Likens, active members of the research team at Hubbard Brook since its beginnings, explain the scientific processes employed in the forest-turned-laboratory.Hubbard Brook Experimental Forest has a continuous record of bulk precipitation and stream chemistry dating from the early 1960s. 38,39 Bulk deposition of nitrate plus ammonium (DIN) averaged ∼7 kg of N ha -1 year -1 from 1965 to 2007 (Table 1), which was similar to other observations in the northeastern United States. 4,5,23 As expected ...Hubbard Brook, the site of our current study, is an outlier by defying the trends of increasing DOC concentrations in surface waters. During the years 1982-2000, stream water DOC declined at Hubbard Brook, coincident with decreased DOC leaching in soil water [Palmer et al., 2004].Watershed 6, Hubbard Brook Experimental Forest, NH HBEF 43°56′N 13.1 490-775 525 1992-1993 6 71°45′W Arbutus Watershed, Huntington Forest, NY HF 43°59′N 309 513-701 358 1992-1993 10 74°14′W Biscuit Brook, NY CS 41°59′N 960 628-1128 570 1985-1986 11 74°25′W FIGURE 1. Monthly nitrate concentrations at the base of watershedAcid rain that mixed with stream water at Hubbard Brook was neutralized by the alumina from soils.[28] The Because its remote conditions allowed for whole-ecosystem experiments, research at the ELA showed that the effect of acid rain on fish populations started at concentrations much lower...Nov 03, 2021 · Bormann, F. H. & Likens, G. E. Pattern and process in a forested ecosystem: disturbance, development and the steady state based on the Hubbard Brook ecosystem study. (Springer Science & Business ... Our work is supported by the National Science Foundation, the USDA Forest Service and other government and private funders. Any opinions, findings, conclusions, and recommendation Hubbard Brook has plentiful rain and sunlight to support a healthy forest. The first unknown that ecologists Through long term monitoring of the stream chemistry at Hubbard Brook, including measurements of The greater the concentration of hydrogen in solution, the more acid a solution is.Sources, transformations, and hydrological processes that control stream nitrate and dissolved organic matter concentrations during snowmelt in an upland forest: STREAM NITRATE AND DOM SOURCES journal, December 2008. Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B. Water Resources Research, Vol. 44, Issue 12; DOI: 10.1029/2008WR006983Some major biogeochemical findings of the Hubbard Brook Ecosystem Study are discussed briefly, including acid rain, and some biogeochemical research questions, opportunities, and challenges for the future are identified, including a recent whole‐watershed addition of calcium silicate, weathering processes, and long‐term trends in stream ...Fig. 1. (A) Nitrate concentrations in stream water from the three experimentally deforested watersheds (W2, W4, and W5).These data are normalized to the [NO 3-] in-stream export from W6, the reference watershed, to more clearly show the effects of the cutting events without including the variation in export common to all six watersheds.(B) Patterns of NO 3-export over the same time period for ...concentrations of nitrate reported for larger, forested basins monitored by the US Geological Survey (Hydrologic Benchmark Network and National Water Quality Assessment Network). At a local scale, no trend in nitrate concentration with stream order or basin size was consistent across studies.A comparison of measured and simulated values of (a) annual discharge and annual volume-weighted concentrations of (b) , (c) , (d) Ca 2+, (e) DOC, and (f) stream water pH over the period 1964-2008 at watershed 6 of the Hubbard Brook Experimental Forest, N. H.2008] or land management changes [Yallop and Clutterbuck, 2009; Holden et al., 2012]. Hubbard Brook, the site of our current study, is an outlier by defying the trends of increasing DOC concentrations in surface waters. During the years 1982-2000, stream water DOC declined at Hubbard Brook, coincident withA synthesis of the biogeochemistry of K was conducted during 1963-1992 in the reference and human-manipulated watershed-ecosystems of the Hubbard Brook Experimental Forest (HBEF), NH. Results showed that during the first two years of the study (1963-65), which coincided with a drought period, the reference watershed was a net sink for atmospheric inputs of K. During the remaining years ...One striking result of the Hubbard Brook Experiment on watershed 2 was the large increase in nitrate in stream water exiting the watershed. Use a simple drawing to show the source of this nitrogen (e.g. where did it mainly come from?) and how this nitrogen is converted into nitrate which ends up in the stream water.10 of 18 W01511 DEMERS ET AL.: EPISODIC ACIDIFICATION AND MERCURY MOBILIZATION W01511 Figure 4. Snowpack, discharge, and stream concentrations of major solutes that regulate the acid-base status of W6 during snowmelt at the Hubbard Brook Experimental Forest.10 of 18 W01511 DEMERS ET AL.: EPISODIC ACIDIFICATION AND MERCURY MOBILIZATION W01511 Figure 4. Snowpack, discharge, and stream concentrations of major solutes that regulate the acid-base status of W6 during snowmelt at the Hubbard Brook Experimental Forest.Calcium was a focus of one of the first studies (Likens et al. 1967) of the Hubbard Brook Ecosystem Study (HBES), and this paper provides an evaluation based on 29 years of intensive study (1963- 1992). This period is sufficiently long to detect temporal changes in Ca fluxes.Hubbard Brook Experimental Forest: Watersheds 1 and 2 All trees in Watershed 2 (the experimental site) were cut in December 1965 and left on top of the snow. In the summers of 1966, 1967, and 1968, two herbicides were applied to the entire watershed to prevent the regrowth of any vegetation. Scientists believe that the herbicidenitrate concentrations were below 0.5 mg/l for both harvested and control watersheds. Exceptions were in the red alder (Alnus rubra) and Douglas-fir (Pseudotsuga menzesii) forests in Or-egon, where equally high levels of nitrate existed in the control and treatment watersheds, and in the hardwood forests of Hubbard Brook. Combine this information with other information previously collected, including from across websites and apps Vendors cannot: *Apply panel- or similarly-derived audience insights data to ad measurement data without a Legal Basis to apply market research to generate audience insights (Purpose 9).Watershed 6, Hubbard Brook Experimental Forest, NH HBEF 43°56′N 13.1 490-775 525 1992-1993 6 71°45′W Arbutus Watershed, Huntington Forest, NY HF 43°59′N 309 513-701 358 1992-1993 10 74°14′W Biscuit Brook, NY CS 41°59′N 960 628-1128 570 1985-1986 11 74°25′W FIGURE 1. Monthly nitrate concentrations at the base of watershedAt Hubbard Brook, no .__ significant increase in nitrate concentration in stream water was observed c_. during 1970, the year of peak insect defoliation. HoGvex-Holmes and Sturges (1975) have shown that during the years when Heterocampu was in outbreak phase, many birds concentrated on.nitrate concentrations were below 0.5 mg/l for both harvested and control watersheds. Exceptions were in the red alder (Alnus rubra) and Douglas-fir (Pseudotsuga menzesii) forests in Or-egon, where equally high levels of nitrate existed in the control and treatment watersheds, and in the hardwood forests of Hubbard Brook. downstream nitrate concentrations, however, is not fully understood. A study of in-stream nitrate dynamics was conducted downstream of the weir on Watershed 3 in the Hubbard Brook Experimental Forest (HBEF). Hubbard Brook (see Vitousek and Melillo, 1979), and that nitrate levels were higher at Hubbard Brook than at most other sites before disturbance as well as after. In western Oregon, Fredriksen et al. (1975)' found that nitrate levels were very low in stream water draining un- disturbed Douglas-fir forests and that, though they rosenitrate concentrations were below 0.5 mg/l for both harvested and control watersheds. Exceptions were in the red alder (Alnus rubra) and Douglas-fir (Pseudotsuga menzesii) forests in Or-egon, where equally high levels of nitrate existed in the control and treatment watersheds, and in the hardwood forests of Hubbard Brook. During a two-month DOC enrichment to a stream in the Hubbard Brook Experimental Forest, Bernhardt and Likens (2002) were able to reduce inorganic nitrogen export from an entire watershed to below analytical detection throughout the period of C enrichment, indicating that the biological capacity for nitrate uptake was limited by labile carbon.Central to the exposé is Brook Jackson, who, for two weeks, served as regional director at Ventavia Research Group, the company contracted to assist with the pivotal trial. She provided The BMJ with dozens of internal company documents, photos, audio recordings, and emails supporting her concerns.Fig. 1. (A) Nitrate concentrations in stream water from the three experimentally deforested watersheds (W2, W4, and W5).These data are normalized to the [NO 3-] in-stream export from W6, the reference watershed, to more clearly show the effects of the cutting events without including the variation in export common to all six watersheds.(B) Patterns of NO 3-export over the same time period for ...Ammonium, urea, and nitrate were added to Bear Brook, a second and third order stream in the Hubbard Brook Experimental Forest, New Hampshire. Removal of ammonium and urea during downstream transport coincided with the release of nitrate. Nitrate removal did not occur when it was added alone or with dissolved organic carbon. Laboratory experiments showed that coarse particulate organic ...nitrate concentrations were below 0.5 mg/l for both harvested and control watersheds. Exceptions were in the red alder (Alnus rubra) and Douglas-fir (Pseudotsuga menzesii) forests in Or-egon, where equally high levels of nitrate existed in the control and treatment watersheds, and in the hardwood forests of Hubbard Brook. Abstract Human activities have increased the availability and distribution of dissolved inorganic N (DIN) in the biosphere. Streams can remove some of this excess DIN, but in-stream uptake pathways of NO3− and NH4+ can be sensitive to the concentration of DIN. DIN uptake kinetics (i.e., changes in uptake in response to changes in concentration) are used to predict how streams will respond to ... Long-term research and monitoring, and large-scale, watershed-scale, experimental manipulations have been hallmarks of the Hubbard Brook Ecosystem Study since 1963 (e.g. Likens et al. 1970, Likens 1985, Likens and Bormann 1995). Based on this research and long-term monitoring, several changing dynamics of this system haveafter 2000 were driven by the storm damage and that stream nitrate effects were movement of Ca added to the Soil solution Nitrogen concentrations in foliage showed no chemistry in the Oa horizon was affected by the coherent Effects of nitrogen 0315211, Hubbard Brook Long Term Research in additions on annual nitrous oxide fluxes from Soil chemistry and istry of calcium at Hubbard Brook.Feb 13, 2012 · At the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, for example, we know that current concentrations of nitrate in watershed streams are the lowest in 46 y of measurement and that ecosystem nitrate losses have decreased by >90% over this time (Fig. 1A). One striking result of the Hubbard Brook Experiment on watershed 2 was the large increase in nitrate in stream water exiting the watershed. Use a simple drawing to show the source of this nitrogen (e.g. where did it mainly come from?) and how this nitrogen is converted into nitrate which ends up in the stream water.The U.S. Department of Energy's Office of Scientific and Technical Information(Hubbard Brook, NH) Dana R. Warren1*, Gene E. Likens2, Donald C. Buso2, and Clifford E. Kraft1 Abstract - Stream acidification across the northeastern US impacts fish abundance and fish communities. In this study, we document a fish community shift in the upper mainstem of Hubbard Brook (NH) from the presence of at least three species in the(A) Nitrate concentrations in stream water from the three experimentally deforested watersheds (W2, W4, and W5). These data are normalized to the [NO 3] in-stream export from W6, the reference watershed, to more clearly show the effects of the cutting events without including the variation in export common to all six watersheds. (B) Patterns of ...All vegetation on Watershed 2 of the Hubbard Brook Experimental Forest was cut during November and December of 1965, and vegetation regrowth was inhibited for two years by periodic application of herbicides. Annual stream-flow was increased 39% the first year and 28% the second year.View Afshin Pourmokhtarian's profile on LinkedIn, the world's largest professional community. Afshin has 6 jobs listed on their profile. See the complete profile on LinkedIn and discover ...The objective of this study was to examine controls on the spatial and temporal patterns in the concentrations and fluxes of nitrogen (N) species and dissolved organic carbon (DOC) in a 12-year record of soil solutions and streamwater along an elevational gradient (540-800 m) of a forested watershed at the Hubbard Brook Experimental Forest ...There is a strong relationship between stream nitrate concentrations before and after disturbance, but there are four strongly divergent outliers (all four outside the 95th percentile confidence limits) (Fig. 2).The first of these, which is well above the trend line, is for the classic study at the Hubbard Brook Experimental Forest (HBEF) involving catchment clear-cut harvesting of an entire ...This reconstruction showed acid rain peaking at HBEF in the late 1960s-early 1970s near the beginning of the Hubbard Brook Ecosystem Study (HBES). The long-term, parabolic arc in acid inputs to HBEF generated a corresponding arc in the ionic strength of stream water, with acid inputs generating increased losses of H + and soil base cations ...[1] This study uses time series analysis to examine long‐term stream water nitrate concentration records from a pair of forested catchments at the Coweeta Hydrologic Laboratory, North Carolina, USA. Monthly average concentrations were available from 1970 through 1997 for two forested catchments, one of which was clear‐felled in 1977 and the other maintained as a control.(A) Nitrate concentrations in stream water from the three experimentally deforested watersheds (W2, W4, and W5). These data are normalized to the [NO 3] in-stream export from W6, the reference watershed, to more clearly show the effects of the cutting events without including the variation in export common to all six watersheds. (B) Patterns of ...Combine this information with other information previously collected, including from across websites and apps Vendors cannot: *Apply panel- or similarly-derived audience insights data to ad measurement data without a Legal Basis to apply market research to generate audience insights (Purpose 9).Oct 06, 2016 · Nitrate concentrations in precipitation did not show any significant trend between 1981 and 2002, but after the implementation of the NO x Budget Trading Program (NBP; established under the NO x State Implementation Plan [SIP] Call Program in 2003; Burtraw and Szambelan 2009) significantly (P < 0.001) decreased at a rate of 0.3 μmol c ·L −1 ... Nitrate was exported in highest concentrations from Watershed 7 during each year, presumably the result of (2005) showed that the deposition of SO42- and NO3- are strongly related to the emissions of Hubbard Brook, the site of this dissertation research, has been shown to be somewhat of an Stream water DOC concentration has shown a long-term decline at Hubbard Brook, apparently...The forest is part of the National Science Foundation's Long-Term Ecological Research program. At sites throughout the forest, the research team measured the presence of nitrate, a form of nitrogen that is highly mobile and reactive in the environment, and determined whether the nitrate was a result of atmospheric deposition or nitrification.Nitrate was exported in highest concentrations from Watershed 7 during each year, presumably the result of (2005) showed that the deposition of SO42- and NO3- are strongly related to the emissions of Hubbard Brook, the site of this dissertation research, has been shown to be somewhat of an Stream water DOC concentration has shown a long-term decline at Hubbard Brook, apparently...and forest succession within catchments. At the Hubbard Brook Experimental Forest in New Hampshire, stream nitrate concentrations have been declining in recent decades after increasing from 1963 into the 1970s (Likens and Bormann 1995, Campbell et al 2007). These trends in stream nitrate at Hubbard Brook have not been explained by changes innual scale, exports of nitrate at the weir would have been 80-140% higher given no stream removal of nitrate. Indeed, after the ice storm, the stream took up more nitrate than the annual export from the base of the watershed. Bernhardt et al. (12) show that that the disturbance itself increased the streams' capacity to retain more nitrate.