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Artikel: Partitioning inorganic carbon fluxes from paired O2–CO2 gas measurements in a Neotropical headwater stream, Costa Rica

Marzolf, Nicholas S. / Small, Gaston E. / Oviedo-Vargas, Diana / Ganong, Carissa N. / Duff, John H. / Ramírez, Alonso / Pringle, Catherine M. / Genereux, David P. / Ardón, Marcelo

Biogeochemistry. 2022 Sept., v. 160, no. 2

2022

Abstract: The role of streams and rivers in the global carbon (C) cycle remains unconstrained, especially in headwater streams where CO₂ evasion (FCO₂) to the atmosphere is high. Stream C cycling is understudied in the tropics compared to temperate streams, and ... ...

Abstract	The role of streams and rivers in the global carbon (C) cycle remains unconstrained, especially in headwater streams where CO₂ evasion (FCO₂) to the atmosphere is high. Stream C cycling is understudied in the tropics compared to temperate streams, and tropical streams may have among the highest FCO₂ due to higher temperatures, continuous organic matter inputs, and high respiration rates both in-stream and in surrounding soils. In this paper, we present paired in-stream O₂ and CO₂ sensor data from a headwater stream in a lowland rainforest in Costa Rica to explore temporal variability in gas concentrations and ecosystem processes. Further, we estimate groundwater CO₂ inputs (GWCO₂) from riparian well CO₂ measurements. Paired O₂–CO₂ data reveal stream CO₂ supersaturation driven by groundwater CO₂ inputs and large in-stream production of CO₂. At short time scales, CO₂ was diluted during storm events, but increased at longer seasonal scales. Areal fluxes in our study reach show that FCO₂ is supported by greater in-stream metabolism compared to GWCO₂. Our results underscore the importance of tropical headwater streams as large contributors of carbon dioxide to the atmosphere and show evaded C can be derived from both in-stream and terrestrial sources.
Schlagwörter	Neotropics ; biogeochemistry ; carbon dioxide ; ecosystems ; groundwater ; inorganic carbon ; metabolism ; organic matter ; rain forests ; storms ; streams ; temporal variation ; Costa Rica
Sprache	Englisch
Erscheinungsverlauf	2022-09
Umfang	p. 259-273.
Erscheinungsort	Springer International Publishing
Dokumenttyp	Artikel
ZDB-ID	1478541-9
ISSN	1573-515X ; 0168-2563
ISSN (online)	1573-515X
ISSN	0168-2563
DOI	10.1007/s10533-022-00954-4
Datenquelle	NAL Katalog (AGRICOLA)

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Artikel: Low transient storage and uptake efficiencies in seven agricultural streams: implications for nutrient demand.

Sheibley, Richard W / Duff, John H / Tesoriero, Anthony J

Journal of environmental quality

2014 Band 43, Heft 6, Seite(n) 1980–1990

Abstract: We used mass load budgets, transient storage modeling, and nutrient spiraling metrics to characterize nitrate (NO), ammonium (NH), and inorganic phosphorus (SRP) demand in seven agricultural streams across the United States and to identify in-stream ... ...

Abstract	We used mass load budgets, transient storage modeling, and nutrient spiraling metrics to characterize nitrate (NO), ammonium (NH), and inorganic phosphorus (SRP) demand in seven agricultural streams across the United States and to identify in-stream services that may control these conditions. Retention of one or all nutrients was observed in all but one stream, but demand for all nutrients was low relative to the mass in transport. Transient storage metrics (/, , , and ) correlated with NO retention but not NH or SRP retention, suggesting in-stream services associated with transient storage and stream water residence time could influence reach-scale NO demand. However, because the fraction of median reach-scale travel time due to transient storage () was ≤1.2% across the sites, only a relatively small demand for NO could be generated by transient storage. In contrast, net uptake of nutrients from the water column calculated from nutrient spiraling metrics were not significant at any site because uptake lengths calculated from background nutrient concentrations were statistically insignificant and therefore much longer than the study reaches. These results suggest that low transient storage coupled with high surface water NO inputs have resulted in uptake efficiencies that are not sufficient to offset groundwater inputs of N. Nutrient retention has been linked to physical and hydrogeologic elements that drive flow through transient storage areas where residence time and biotic contact are maximized; however, our findings indicate that similar mechanisms are unable to generate a significant nutrient demand in these streams relative to the loads.
Sprache	Englisch
Erscheinungsdatum	2014-11
Erscheinungsland	United States
Dokumenttyp	Journal Article
ZDB-ID	120525-0
ISSN	1537-2537 ; 0047-2425
ISSN (online)	1537-2537
ISSN	0047-2425
DOI	10.2134/jeq2014.01.0034
Datenquelle	MEDical Literature Analysis and Retrieval System OnLINE

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Artikel: Low Transient Storage and Uptake Efficiencies in Seven Agricultural Streams: Implications for Nutrient Demand

Sheibley, Richard W / Duff, John H / Tesoriero, Anthony J

Journal of environmental quality. 2014 Nov., v. 43, no. 6

2014

Abstract: We used mass load budgets, transient storage modeling, and nutrient spiraling metrics to characterize nitrate (NO3−), ammonium (NH4+), and inorganic phosphorus (SRP) demand in seven agricultural streams across the United States and to identify in-stream ... ...

Abstract	We used mass load budgets, transient storage modeling, and nutrient spiraling metrics to characterize nitrate (NO3−), ammonium (NH4+), and inorganic phosphorus (SRP) demand in seven agricultural streams across the United States and to identify in-stream services that may control these conditions. Retention of one or all nutrients was observed in all but one stream, but demand for all nutrients was low relative to the mass in transport. Transient storage metrics (As/A, Fmed200, Tstr, and qs) correlated with NO3− retention but not NH4+ or SRP retention, suggesting in-stream services associated with transient storage and stream water residence time could influence reach-scale NO3− demand. However, because the fraction of median reach-scale travel time due to transient storage (Fmed200) was ≤1.2% across the sites, only a relatively small demand for NO3− could be generated by transient storage. In contrast, net uptake of nutrients from the water column calculated from nutrient spiraling metrics were not significant at any site because uptake lengths calculated from background nutrient concentrations were statistically insignificant and therefore much longer than the study reaches. These results suggest that low transient storage coupled with high surface water NO3− inputs have resulted in uptake efficiencies that are not sufficient to offset groundwater inputs of N. Nutrient retention has been linked to physical and hydrogeologic elements that drive flow through transient storage areas where residence time and biotic contact are maximized; however, our findings indicate that similar mechanisms are unable to generate a significant nutrient demand in these streams relative to the loads.
Schlagwörter	ammonium ; groundwater ; inorganic phosphorus ; models ; nitrates ; nutrient content ; nutrient uptake ; nutrients ; streams ; surface water ; United States
Sprache	Englisch
Erscheinungsverlauf	2014-11
Umfang	p. 1980-1990.
Erscheinungsort	The American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.
Dokumenttyp	Artikel
Anmerkung	epub
ZDB-ID	120525-0
ISSN	1537-2537 ; 0047-2425
ISSN (online)	1537-2537
ISSN	0047-2425
DOI	10.2134/jeq2014.01.0034
Datenquelle	NAL Katalog (AGRICOLA)

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Artikel: Role of the fish Astyanax aeneus (Characidae) as a keystone nutrient recycler in low-nutrient neotropical streams.

Small, Gaston E / Pringle, Catherine M / Pyron, Mark / Duff, John H

Ecology

2011 Band 92, Heft 2, Seite(n) 386–397

Abstract: Nutrient recycling by animals is a potentially important biogeochemical process in both terrestrial and aquatic ecosystems. Stoichiometric traits of individual species may result in some taxa playing disproportionately important roles in the recycling of ...

Abstract	Nutrient recycling by animals is a potentially important biogeochemical process in both terrestrial and aquatic ecosystems. Stoichiometric traits of individual species may result in some taxa playing disproportionately important roles in the recycling of nutrients relative to their biomass, acting as keystone nutrient recyclers. We examined factors controlling the relative contribution of 12 Neotropical fish species to nutrient recycling in four streams spanning a range of phosphorus (P) levels. In high-P conditions (135 microg/L soluble reactive phosphorus, SRP), most species fed on P-enriched diets and P excretion rates were high across species. In low-P conditions (3 microg/L SRP), aquatic food resources were depleted in P, and species with higher body P content showed low rates of P recycling. However, fishes that were subsidized by terrestrial inputs were decoupled from aquatic P availability and therefore excreted P at disproportionately high rates. One of these species, Astyanax aeneus (Characidae), represented 12% of the total population and 18% of the total biomass of the fish assemblage in our focal low-P study stream but had P excretion rates > 10-fold higher than other abundant fishes. As a result, we estimated that P excretion by A. aeneus accounted for 90% of the P recycled by this fish assemblage and also supplied approximately 90% of the stream P demand in this P-limited ecosystem. Nitrogen excretion rates showed little variation among species, and the contribution of a given species to ecosystem N recycling was largely dependent upon the total biomass of that species. Because of the high variability in P excretion rates among fish species, ecosystem-level P recycling could be particularly sensitive to changes in fish community structure in P-limited systems.
Mesh-Begriff(e)	Animals ; Ecosystem ; Feeding Behavior/physiology ; Fishes/physiology ; Nitrogen/metabolism ; Phosphorus ; Rivers
Chemische Substanzen	Phosphorus (27YLU75U4W) ; Nitrogen (N762921K75)
Sprache	Englisch
Erscheinungsdatum	2011-03-28
Erscheinungsland	United States
Dokumenttyp	Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
ZDB-ID	1797-8
ISSN	0012-9658
ISSN	0012-9658
DOI	10.1890/10-0081.1
Datenquelle	MEDical Literature Analysis and Retrieval System OnLINE

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Artikel ; Online: Vulnerability of streams to legacy nitrate sources.

Tesoriero, Anthony J / Duff, John H / Saad, David A / Spahr, Norman E / Wolock, David M

Environmental science & technology

2013 Band 47, Heft 8, Seite(n) 3623–3629

Abstract: The influence of hydrogeologic setting on the susceptibility of streams to legacy nitrate was examined at seven study sites having a wide range of base flow index (BFI) values. BFI is the ratio of base flow to total streamflow volume. The portion of ... ...

Abstract	The influence of hydrogeologic setting on the susceptibility of streams to legacy nitrate was examined at seven study sites having a wide range of base flow index (BFI) values. BFI is the ratio of base flow to total streamflow volume. The portion of annual stream nitrate loads from base flow was strongly correlated with BFI. Furthermore, dissolved oxygen concentrations in streambed pore water were significantly higher in high BFI watersheds than in low BFI watersheds suggesting that geochemical conditions favor nitrate transport through the bed when BFI is high. Results from a groundwater-surface water interaction study at a high BFI watershed indicate that decades old nitrate-laden water is discharging to this stream. These findings indicate that high nitrate levels in this stream may be sustained for decades to come regardless of current practices. It is hypothesized that a first approximation of stream vulnerability to legacy nutrients may be made by geospatial analysis of watersheds with high nitrogen inputs and a strong connection to groundwater (e.g., high BFI).
Mesh-Begriff(e)	Chlorides/analysis ; Geological Phenomena ; Groundwater/chemistry ; Nitrates/analysis ; Nitrogen/analysis ; Oxygen/analysis ; Porosity ; Rivers/chemistry ; Water/chemistry
Chemische Substanzen	Chlorides ; Nitrates ; Water (059QF0KO0R) ; Nitrogen (N762921K75) ; Oxygen (S88TT14065)
Sprache	Englisch
Erscheinungsdatum	2013-04-16
Erscheinungsland	United States
Dokumenttyp	Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
ISSN	1520-5851
ISSN (online)	1520-5851
DOI	10.1021/es305026x
Datenquelle	MEDical Literature Analysis and Retrieval System OnLINE

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Artikel: Vulnerability of Streams to Legacy Nitrate Sources

Tesoriero, Anthony J / Duff John H / Saad David A / Spahr Norman E / Wolock David M

Environmental Science & Technology. 2013 Apr. 16, v. 47, no. 8

2013

Abstract	The influence of hydrogeologic setting on the susceptibility of streams to legacy nitrate was examined at seven study sites having a wide range of base flow index (BFI) values. BFI is the ratio of base flow to total streamflow volume. The portion of annual stream nitrate loads from base flow was strongly correlated with BFI. Furthermore, dissolved oxygen concentrations in streambed pore water were significantly higher in high BFI watersheds than in low BFI watersheds suggesting that geochemical conditions favor nitrate transport through the bed when BFI is high. Results from a groundwaterâsurface water interaction study at a high BFI watershed indicate that decades old nitrate-laden water is discharging to this stream. These findings indicate that high nitrate levels in this stream may be sustained for decades to come regardless of current practices. It is hypothesized that a first approximation of stream vulnerability to legacy nutrients may be made by geospatial analysis of watersheds with high nitrogen inputs and a strong connection to groundwater (e.g., high BFI).
Schlagwörter	base flow ; groundwater ; nitrates ; nitrogen ; nutrients ; oxygen ; stream channels ; watersheds
Sprache	Englisch
Erscheinungsverlauf	2013-0416
Umfang	p. 3623-3629.
Erscheinungsort	American Chemical Society
Dokumenttyp	Artikel
ISSN	1520-5851
DOI	10.1021%2Fes305026x
Datenquelle	NAL Katalog (AGRICOLA)

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Artikel: Importance of Terrestrial Arthropods as Subsidies in Lowland Neotropical Rain Forest Stream Ecosystems

Small, Gaston E / Torres, Pedro J / Schweizer, Lauren M / Duff, John H / Pringle, Catherine M

Biotropica. 2013 Jan., v. 45, no. 1

2013

Abstract: The importance of terrestrial arthropods has been documented in temperate stream ecosystems, but little is known about the magnitude of these inputs in tropical streams. Terrestrial arthropods falling from the canopy of tropical forests may be an ... ...

Abstract	The importance of terrestrial arthropods has been documented in temperate stream ecosystems, but little is known about the magnitude of these inputs in tropical streams. Terrestrial arthropods falling from the canopy of tropical forests may be an important subsidy to tropical stream food webs and could also represent an important flux of nitrogen (N) and phosphorus (P) in nutrient‐poor headwater streams. We quantified input rates of terrestrial insects in eight streams draining lowland tropical wet forest in Costa Rica. In two focal headwater streams, we also measured capture efficiency by the fish assemblage and quantified terrestrially derived N‐ and P‐excretion relative to stream nutrient uptake rates. Average input rates of terrestrial insects ranged from 5 to 41� mg� dry� mass/m²/d, exceeding previous measurements of aquatic invertebrate secondary production in these study streams, and were relatively consistent year‐round, in contrast to values reported in temperate streams. Terrestrial insects accounted for half of the diet of the dominant fish species, Priapicthys annectens. Although terrestrially derived fish excretion was found to be a small flux relative to measured nutrient uptake rates in the focal streams, the efficient capture and processing of terrestrial arthropods by fish made these nutrients available to the local stream ecosystem. This aquatic‐terrestrial linkage is likely being decoupled by deforestation in many tropical regions, with largely unknown but potentially important ecological consequences.
Schlagwörter	aquatic invertebrates ; arthropods ; canopy ; deforestation ; diet ; ecosystems ; excretion ; fish ; food webs ; nitrogen ; nutrient availability ; nutrient uptake ; phosphorus ; rain forests ; secondary productivity ; streams ; subsidies ; tropical forests ; tropics ; Costa Rica
Sprache	Englisch
Erscheinungsverlauf	2013-01
Umfang	p. 80-87.
Erscheinungsort	Association for Tropical Biology
Dokumenttyp	Artikel
ZDB-ID	2052061-X
ISSN	1744-7429 ; 0006-3606
ISSN (online)	1744-7429
ISSN	0006-3606
DOI	10.1111/j.1744-7429.2012.00896.x
Datenquelle	NAL Katalog (AGRICOLA)

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Artikel ; Online: Experimental acidification of two biogeochemically-distinct neotropical streams: buffering mechanisms and macroinvertebrate drift.

Ardón, Marcelo / Duff, John H / Ramírez, Alonso / Small, Gaston E / Jackman, Alan P / Triska, Frank J / Pringle, Catherine M

The Science of the total environment

2013 Band 443, Seite(n) 267–277

Abstract: Research into the buffering mechanisms and ecological consequences of acidification in tropical streams is lacking. We have documented seasonal and episodic acidification events in streams draining La Selva Biological Station, Costa Rica. Across this ... ...

Abstract	Research into the buffering mechanisms and ecological consequences of acidification in tropical streams is lacking. We have documented seasonal and episodic acidification events in streams draining La Selva Biological Station, Costa Rica. Across this forested landscape, the severity in seasonal and episodic acidification events varies due to interbasin groundwater flow (IGF). Streams that receive IGF have higher concentrations of solutes and more stable pH (~6) than streams that do not receive IGF (pH ~5). To examine the buffering capacity and vulnerability of macroinvertebrates to short-term acidification events, we added hydrochloric acid to acidify a low-solute, poorly buffered (without IGF) and a high-solute, well buffered stream (with IGF). We hypothesized that: 1) protonation of bicarbonate (HCO(3)(-)) would neutralize most of the acid added in the high-solute stream, while base cation release from the sediments would be the most important buffering mechanism in the low-solute stream; 2) pH declines would mobilize inorganic aluminum (Ali) from sediments in both streams; and 3) pH declines would increase macroinvertebrate drift in both streams. We found that the high-solute stream neutralized 745 μeq/L (96% of the acid added), while the solute poor stream only neutralized 27.4 μeq/L (40%). Protonation of HCO(3)(-) was an important buffering mechanism in both streams. Base cation, Fe(2+), and Ali release from sediments and protonation of organic acids also provided buffering in the low-solute stream. We measured low concentrations of Ali release in both streams (2-9 μeq/L) in response to acidification, but the low-solute stream released double the amount Ali per 100 μeq of acid added than the high solute stream. Macroinvertebrate drift increased in both streams in response to acidification and was dominated by Ephemeroptera and Chironomidae. Our results elucidate the different buffering mechanisms in tropical streams and suggest that low-solute poorly buffered streams might be particularly vulnerable to episodic acidification.
Mesh-Begriff(e)	Acids/chemistry ; Animals ; Hydrogen-Ion Concentration ; Invertebrates ; Tropical Climate
Chemische Substanzen	Acids
Sprache	Englisch
Erscheinungsdatum	2013-01-15
Erscheinungsland	Netherlands
Dokumenttyp	Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
ZDB-ID	121506-1
ISSN	1879-1026 ; 0048-9697
ISSN (online)	1879-1026
ISSN	0048-9697
DOI	10.1016/j.scitotenv.2012.10.068
Datenquelle	MEDical Literature Analysis and Retrieval System OnLINE

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Artikel: Experimental acidification of two biogeochemically-distinct neotropical streams: Buffering mechanisms and macroinvertebrate drift

Ardón, Marcelo / Duff, John H / Ramírez, Alonso / Small, Gaston E / Jackman, Alan P / Triska, Frank J / Pringle, Catherine M

Science of the total environment. 2013 Jan. 15, v. 443

2013

Abstract	Research into the buffering mechanisms and ecological consequences of acidification in tropical streams is lacking. We have documented seasonal and episodic acidification events in streams draining La Selva Biological Station, Costa Rica. Across this forested landscape, the severity in seasonal and episodic acidification events varies due to interbasin groundwater flow (IGF). Streams that receive IGF have higher concentrations of solutes and more stable pH (~6) than streams that do not receive IGF (pH ~5). To examine the buffering capacity and vulnerability of macroinvertebrates to short-term acidification events, we added hydrochloric acid to acidify a low-solute, poorly buffered (without IGF) and a high-solute, well buffered stream (with IGF). We hypothesized that: 1) protonation of bicarbonate (HCO₃⁻) would neutralize most of the acid added in the high-solute stream, while base cation release from the sediments would be the most important buffering mechanism in the low-solute stream; 2) pH declines would mobilize inorganic aluminum (Ali) from sediments in both streams; and 3) pH declines would increase macroinvertebrate drift in both streams. We found that the high-solute stream neutralized 745μeq/L (96% of the acid added), while the solute poor stream only neutralized 27.4μeq/L (40%). Protonation of HCO₃⁻ was an important buffering mechanism in both streams. Base cation, Fe²⁺, and Ali release from sediments and protonation of organic acids also provided buffering in the low-solute stream. We measured low concentrations of Ali release in both streams (2-9μeq/L) in response to acidification, but the low-solute stream released double the amount Ali per 100μeq of acid added than the high solute stream. Macroinvertebrate drift increased in both streams in response to acidification and was dominated by Ephemeroptera and Chironomidae. Our results elucidate the different buffering mechanisms in tropical streams and suggest that low-solute poorly buffered streams might be particularly vulnerable to episodic acidification.
Schlagwörter	Chironomidae ; Ephemeroptera ; acidification ; aluminum ; bicarbonates ; buffering capacity ; buffers ; cations ; groundwater flow ; hydrochloric acid ; landscapes ; macroinvertebrates ; organic acids and salts ; pH ; sediments ; solutes ; somatomedins ; streams ; Costa Rica
Sprache	Englisch
Erscheinungsverlauf	2013-0115
Umfang	p. 267-277.
Erscheinungsort	Elsevier B.V.
Dokumenttyp	Artikel
ZDB-ID	121506-1
ISSN	1879-1026 ; 0048-9697
ISSN (online)	1879-1026
ISSN	0048-9697
DOI	10.1016/j.scitotenv.2012.10.068
Datenquelle	NAL Katalog (AGRICOLA)

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Artikel: Identifying pathways and processes affecting nitrate and orthophosphate inputs to streams in agricultural watersheds.

Tesoriero, Anthony J / Duff, John H / Wolock, David M / Spahr, Norman E / Almendinger, James E

Journal of environmental quality

2009 Band 38, Heft 5, Seite(n) 1892–1900

Abstract: Understanding nutrient pathways to streams will improve nutrient management strategies and estimates of the time lag between when changes in land use practices occur and when water quality effects that result from these changes are observed. Nitrate and ... ...

Abstract	Understanding nutrient pathways to streams will improve nutrient management strategies and estimates of the time lag between when changes in land use practices occur and when water quality effects that result from these changes are observed. Nitrate and orthophosphate (OP) concentrations in several environmental compartments were examined in watersheds having a range of base flow index (BFI) values across the continental United States to determine the dominant pathways for water and nutrient inputs to streams. Estimates of the proportion of stream nitrate that was derived from groundwater increased as BFI increased. Nitrate concentration gradients between groundwater and surface water further supported the groundwater source of nitrate in these high BFI streams. However, nitrate concentrations in stream-bed pore water in all settings were typically lower than stream or upland groundwater concentrations, suggesting that nitrate discharge to streams was not uniform through the bed. Rather, preferential pathways (e.g., springs, seeps) may allow high nitrate groundwater to bypass sites of high biogeochemical transformation. Rapid pathway compartments (e.g., overland flow, tile drains) had OP concentrations that were typically higher than in streams and were important OP conveyers in most of these watersheds. In contrast to nitrate, the proportion of stream OP that is derived from ground water did not systematically increase as BFI increased. While typically not the dominant source of OP, groundwater discharge was an important pathway of OP transport to streams when BFI values were very high and when geochemical conditions favored OP mobility in groundwater.
Mesh-Begriff(e)	Environmental Monitoring ; Indiana ; Maryland ; Minnesota ; Nebraska ; Nitrates/analysis ; Nitrates/chemistry ; Phosphates/analysis ; Phosphates/chemistry ; Rivers/chemistry ; Washington ; Water Movements ; Water Supply
Chemische Substanzen	Nitrates ; Phosphates
Sprache	Englisch
Erscheinungsdatum	2009-09
Erscheinungsland	United States
Dokumenttyp	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	120525-0
ISSN	1537-2537 ; 0047-2425
ISSN (online)	1537-2537
ISSN	0047-2425
DOI	10.2134/jeq2008.0484
Datenquelle	MEDical Literature Analysis and Retrieval System OnLINE

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