New insights on resource stoichiometry: assessing availability of carbon, nitrogen, and phosphorus to bacterioplankton

Abstract. Boreal lake and river ecosystems receive large quantities of organic nutrients and carbon (C) from their catchments. How bacterioplankton respond to these inputs is not well understood, in part because we base our understanding and predictions on total pools, yet we know little about the stoichiometry of bioavailable elements within organic matter. We designed bioassays with the purpose of exhausting the pools of readily bioavailable dissolved organic carbon (BDOC), bioavailable dissolved nitrogen (BDN), and bioavailable dissolved phosphorus (BDP) as fast as possible. Applying the method in four boreal lakes at base-flow conditions yielded concentrations of bioavailable resources in the range 105–693 µg C L−1 for BDOC (2 % of initial total DOC), 24–288 µg N L−1 for BDN (31 % of initial total dissolved nitrogen), and 0.2–17 µg P L−1 for BDP (49 % of initial total dissolved phosphorus). Thus, relative bioavailability increased from carbon (C) to nitrogen (N) to phosphorus (P). We show that the main fraction of bioavailable nutrients is organic, representing 80 % of BDN and 61 % of BDP. In addition, we demonstrate that total C : N and C : P ratios are as much as 13-fold higher than C : N and C : P ratios for bioavailable resource fractions. Further, by applying additional bioavailability measurements to seven widely distributed rivers, we provide support for a general pattern of relatively high bioavailability of P and N in relation to C. Altogether, our findings underscore the poor availability of C for support of bacterial metabolism in boreal C-rich freshwaters, and suggest that these ecosystems are very sensitive to increased input of bioavailable DOC.

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New insights on resource stoichiometry: assessing availability of carbon, nitrogen and phosphorus to bacterioplankton

10.5194/bg-2016-440 ◽

2016 ◽

Author(s):

Ana R. A. Soares ◽

Ann-Kristin Bergström ◽

Ryan A. Sponseller ◽

Joanna M. Moberg ◽

Reiner Giesler ◽

...

Keyword(s):

General Pattern ◽

Relative Bioavailability ◽

Boreal Lakes ◽

Base Flow ◽

Limiting Factor ◽

Nitrogen And Phosphorus ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen ◽

Total Dissolved Nitrogen ◽

Nutrient Resources

Abstract. Boreal lake and river ecosystems receive large quantities of organic nutrients and carbon (C) from their 10 catchments. How bacterioplankton respond to these inputs is not well understood, in part because we base our understanding and predictions on "total pools", yet we know little about the stoichiometry of bioavailable elements within the organic matter. We designed bioassays with the purpose to exhaust the pools of readily bioavailable dissolved organic carbon (BDOC), bioavailable dissolved nitrogen (BDN) and bioavailable dissolved phosphorus (BDP) as fast as possible. Applying the method in four boreal lakes at base flow conditions yielded concentrations of bioavailable resources that ranged from 105–693 μg C L−1 for BDOC (2 % of total DOC), 24–288 μg N L−1 for BDN (31 % of total dissolved nitrogen) and 0.2–17 μg P L−1 for BDP (49 % of total dissolved phosphorus). Thus, relative bioavailability increased from carbon (C) to nitrogen (N) to phosphorus (P). We show that the main part of bioavailable nutrient resources is organic, representing 80 % of BDN and 61 % of BDP. In addition, we demonstrate that total C : N and C : P ratios are as much as 13-fold higher than C : N and C : P ratios for bioavailable resource fractions. Further, by applying additional bioavailability measurements to seven widely 20 distributed rivers, we provide support for a general pattern of relatively high bioavailability of P and N in relation to C. Altogether, our findings underscore the role of C as limiting factor for bacterial growth in boreal C-rich freshwaters, and suggest that these ecosystems are very sensitive to increased input of bioavailable DOC.

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Distributions and stoichiometry of dissolved nitrogen and phosphorus in the iron-fertilized region near Kerguelen (Southern Ocean)

Biogeosciences ◽

10.5194/bg-12-623-2015 ◽

2015 ◽

Vol 12 (2) ◽

pp. 623-635 ◽

Cited By ~ 27

Author(s):

S. Blain ◽

J. Capparos ◽

A. Guéneuguès ◽

I. Obernosterer ◽

L. Oriol

Keyword(s):

Southern Ocean ◽

Organic Nitrogen ◽

Organic Phosphorus ◽

Polar Front ◽

Nitrogen And Phosphorus ◽

Phosphorus Species ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen ◽

Total Dissolved Nitrogen ◽

Preferential Uptake

Abstract. During KEOPS2 (Kerguelen Ocean and Plateau Compared Study 2), we determined dissolved inorganic and organic nitrogen and phosphorus species in the naturally fertilized region of Kerguelen Island (Southern Ocean). Above 150 m, stations were clearly separated by the polar front (PF), with concentrations of NO3-, NO2- and PO43- overall lower north of the PF than south. Though less pronounced, a similar trend was detectable for dissolved organic nitrogen (DON) and dissolved organic phosphorus (DOP). At all stations offshore and above the plateau, a subsurface maximum of NH4+ was observed between 50 and 150 m. We examined nutrient stoichiometry by calculating the linear combination N* = [NO3-]-16 [PO43-]. The majority of stations and depths revealed N* close to −3 μM; however, for surface waters north of the PF, N* increased up to 6 μM. This suggests a preferential uptake of PO43- versus NO3- by fast-growing diatoms. Using the tracer TNxs = [TDN]-16[TDP] (TDN, total dissolved nitrogen; TDP, total dissolved phosphorus) revealed that the dissolved organic fraction significantly contributed to changes in TNxs. TNxs values were negative for most stations and depths, and relatively constant in the 0–500 m layer. As for N*, the stations north of the PF had higher TNxs in the 0–100 m layer. We discuss this stoichiometric anomaly with respect to possible external sources and sinks of N and P. Additional data collected in February 2013 at two sites revealed the occurrence of a subsurface minimum of N* located just below the pycnocline, which denotes a layer where remineralization of particulate organic matter with low N : P ratio P, possibly associated with preferential remineralization of P versus N, persists throughout the season.

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Preliminary Chemical Characterization of Waters in the Experimental Lakes Area, Northwestern Ontario

Journal of the Fisheries Research Board of Canada ◽

10.1139/f71-030 ◽

1971 ◽

Vol 28 (2) ◽

pp. 171-187 ◽

Cited By ~ 87

Author(s):

F. A. J. Armstrong ◽

D. W. Schindler

Keyword(s):

Chemical Characterization ◽

Specific Conductance ◽

Canadian Shield ◽

Nitrogen And Phosphorus ◽

Experimental Lakes Area ◽

Mean Values ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen ◽

Total Dissolved Nitrogen ◽

Northwestern Ontario

Water analyses in 1968 and 1969 from 40 small lakes within a small area of the Canadian Shield in northwestern Ontario gave mean values for Ca, Na, Mg, and K of 1.6, 0.9, 0.9, and 0.4 mg/liter with Ca > Na > Mg > K on a molar basis. HCO3, SO4, and Cl (on a smaller number of samples) were 4.1, 3.0, and 1.4 mg/liter. Total CO2 was variable in the range 0.3–12.0 mg/liter. Specific conductance was in the range 10–35 μmho/cm at 25 C and pH 5.4–7.5. Color was < 5–150 Hazen units, and plant pigments (as chlorophyll a) < 1–21 μg/liter. Total dissolved nitrogen was in the range 110–300 mg N/liter and total dissolved phosphorus 3–20 μg P/liter. NO3-N and PO4-P were often undetectable in summer, and reached winter maxima around 100 and 10 μg/liter.Total dissolved nitrogen and phosphorus contents of five lakes were computed at the beginning and end of periods of several weeks during summer stagnation. Changes were negligibly small in three of the deeper lakes, but the two shallowest showed increases of 0.22 and 0.62 g N/m2 and 0.03 and 0.13 g P/m2. Analyses of precipitation and stream waters were used, with stream flow rates, to calculate input and output of nutrients from four of these lakes during the same periods. Retention of nutrients had occurred in all, and it was concluded that in the two deeper lakes nutrients had been lost to the sediments, whereas in the two shallower ones the increases in dissolved nutrients found were derived from the sediments.Analyses of 33 other Canadian Shield lake areas and of 13 other dilute lakes in other regions are tabulated. Comparison with the Experimental Lakes Area (ELA) lakes shows that the latter are more dilute than any in the Shield area except for some in the Northwest Territories, and much more dilute than any others in the world except for some alpine lakes in California.

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Efficiency of aquatic macrophytes to treat Nile tilapia pond effluents

Scientia Agricola ◽

10.1590/s0103-90162006000500003 ◽

2006 ◽

Vol 63 (5) ◽

pp. 433-438 ◽

Cited By ~ 45

Author(s):

Gustavo Gonzaga Henry-Silva ◽

Antonio Fernando Monteiro Camargo

Keyword(s):

Total Nitrogen ◽

Total Phosphorus ◽

Nile Tilapia ◽

Aquatic Macrophytes ◽

Fish Farming ◽

Pistia Stratiotes ◽

Fish Pond ◽

Nitrogen And Phosphorus ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen

The effluents from fish farming can increase the quantity of suspended solids and promote the enrichment of nitrogen and phosphorus in aquatic ecosystems. In this context, the aim of this work was to evaluate the efficiency of three species of floating aquatic macrophytes (Eichhornia crassipes, Pistia stratiotes and Salvinia molesta) to treat effluents from Nile tilapia culture ponds. The effluent originated from a 1,000-m² pond stocked with 2,000 male Nile tilapia Oreochromis niloticus. The treatment systems consisted of 12 experimental tanks, three tanks for each macrophyte species, and three control tanks (without plants). Water samples were collected from the: (i) fish pond source water, (ii) effluent from fish pond and (iii) effluents from the treatment tanks. The following water variables were evaluated: turbidity, total and dissolved nitrogen, ammoniacal-N, nitrate-N, nitrite-N, total phosphorus and dissolved phosphorus. E. crassipes and P. stratiotes were more efficient in total phosphorus removal (82.0% and 83.3%, respectively) and total nitrogen removal (46.1% and 43.9%, respectively) than the S. molesta (72.1% total phosphorus and 42.7% total nitrogen) and the control (50.3% total phosphorus and 22.8% total nitrogen), indicating that the treated effluents may be reused in the aquaculture activity.

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A modified segmented continuous flow analysis method for simultaneous determination of total dissolved nitrogen and phosphorus in marine environments

Limnology and Oceanography Methods ◽

10.4319/lom.2014.12.577 ◽

2014 ◽

Vol 12 (8) ◽

pp. 577-591 ◽

Cited By ~ 8

Author(s):

Evgeny V. Dafner ◽

Alina M. Szmant

Keyword(s):

Simultaneous Determination ◽

Continuous Flow ◽

Flow Analysis ◽

Marine Environments ◽

Analysis Method ◽

Nitrogen And Phosphorus ◽

Dissolved Nitrogen ◽

Total Dissolved Nitrogen ◽

Continuous Flow Analysis

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Investigation of nitrogen and phosphorus contents in water in the tributaries of Danjiangkou Reservoir

Royal Society Open Science ◽

10.1098/rsos.170624 ◽

2018 ◽

Vol 5 (1) ◽

pp. 170624 ◽

Cited By ~ 4

Author(s):

Yan Liu ◽

Yuanyuan Zhu ◽

Xiaocui Qiao ◽

Binghui Zheng ◽

Sheng Chang ◽

...

Keyword(s):

Inorganic Nitrogen ◽

Organic Pollution ◽

Test Results ◽

Nitrogen And Phosphorus ◽

Danjiangkou Reservoir ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen ◽

Quality Water ◽

The Government ◽

Surface Water Samples

As part of the efforts to ensure adequate supply of quality water from Danjiangkou Reservoir to Beijing, surface water samples were taken from the tributaries of Danjiangkou Reservoir in the normal (May), flood (August) and dry (December) seasons of 2014, and characterized for nitrogen and phosphorus contents as specified in the applicable standards. Test results indicated that (i) the organic pollution in the Sihe and Shendinghe rivers was more serious than those in other tributaries, and the concentrations of nitrogen and phosphorus favoured the growth of most algae; (ii) total phosphorus (TP), total nitrogen (TN) and dissolved inorganic nitrogen (DIN) were in the forms of dissolved phosphorus (DTP), dissolved nitrogen (DTN) and nitrate nitrogen ( NO 3 − -N ) , respectively, in these seasons; (iii) compared with nitrogen, phosphorus was more likely to block an overrun of phytoplankton; (iv) TN, TP, permanganate index (COD Mn ) and other ions were positively correlated. These findings are helpful for the government to develop effective measures to protect the source water in Danjingkou Reservoir from pollution.

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Responses of Free-Living Vibrio Community to Seasonal Environmental Variation in a Subtropical Inland Bay

Frontiers in Microbiology ◽

10.3389/fmicb.2020.610974 ◽

2020 ◽

Vol 11 ◽

Author(s):

Xing Chen ◽

Huaxian Zhao ◽

Gonglingxia Jiang ◽

Jinli Tang ◽

Qiangsheng Xu ◽

...

Keyword(s):

Inorganic Nitrogen ◽

Environmental Variation ◽

Mantel Test ◽

Beibu Gulf ◽

Test Analysis ◽

Dissolved Phosphorus ◽

Dissolved Nitrogen ◽

Β Diversity ◽

Total Dissolved Nitrogen ◽

Filtering Effect

Vibrio are widely distributed in aquatic environments and strongly associated with eutrophic environments and human health through the consumption of contaminated seafood. However, the response of the Vibrio community to seasonal variation in eutrophic environments is poorly understood. In this study, we used a Vibrio-specific 16S rRNA sequencing approach to reveal the seasonal distribution pattern and diversity of the Vibrio community in the Maowei Sea, Beibu Gulf of China. The Shannon diversity of the Vibrio community was highest in the summer, while β-diversity analysis showed that Vibrio community structures were significantly different between seasons. Distance-based redundancy analysis (dbRDA) and Mantel test analysis suggested that total dissolved nitrogen (TDN), total dissolved phosphorus (TDP), dissolved inorganic nitrogen (DIN), salinity, and temperature were the key environmental factors shaping the Vibrio community structure, indicating a strong filtering effect of trophic condition on Vibrio communities. Furthermore, through random forest analysis, V. fluvialis, V. alginolyticus, V. proteolyticus, V. splendidus, and the other eight Vibrio species were more sensitive to eutrophic changes. This study revealed seasonal changes in Vibrio communities and the influence of environmental variation on Vibrio community composition, contributing to a better understanding of their potential ecological roles in a subtropical inland bay.

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Composition and Dynamics of Phytoplankton in the Coastal Bays of Maryland, USA, Revealed by Microscopic Counts and Diagnostic Pigments Analyses

Water ◽

10.3390/w11020368 ◽

2019 ◽

Vol 11 (2) ◽

pp. 368 ◽

Cited By ~ 3

Author(s):

Ozuem Oseji ◽

Chunlei Fan ◽

Paulinus Chigbu

Keyword(s):

Phytoplankton Community ◽

Anthropogenic Impacts ◽

Dissolved Phosphorus ◽

Coastal Bays ◽

Toxic Species ◽

Dissolved Nitrogen ◽

The Past ◽

Total Dissolved Nitrogen ◽

Maryland Coastal Bays ◽

First Time

Maryland Coastal Bays (MCBs) have undergone changes in water quality in the past two decades due to nutrient enrichment but the composition and dynamics of the phytoplankton community have not been adequately described. Microscopic counts and photosynthetic pigments of samples collected monthly in 2012 at selected sites in MCBs that differed with regard to the degree of anthropogenic impacts were examined. Sixty-three (63) phytoplankton genera were recorded, of which 40 species are being reported for the first time in the Bays. Among the dominant species were Dactyliosolen fragilissimus (Bacillariophyta), Paulinella ovalis (Cercozoa) and Cryptomonas sp. (Cryptophyta). Bloom densities of Heterocapsa rotundata (Miozoa), which previously had not been reported in the Bays, were observed bay-wide in December, particularly at the mouth of St. Martin River. Diatoms dominated (>40%) the phytoplankton community in winter and decreased in spring (<40%), while Cercozoa and microphytoflagellates (MPF) co-dominated in summer (July). From August to October, diatoms dominated with maximum contributions from an unidentified small (<10 µM) centric species and co-dominated the assemblage with cryptophytes in late fall (November). Canonical correspondence analysis indicated that diatoms were favored by high salinity and total dissolved phosphorus (TDP), cercozoans and chlorophytes by total dissolved nitrogen (TDN) and cryptophytes by dissolved organic carbon. The spatial and seasonal differences in the composition of phytoplankton species, coupled with the occurrence of potentially toxic species and bloom densities of H. rotundata suggest that important changes have occurred in the phytoplankton assemblage that likely have affected the food web of these eutrophic bays.

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Salt Marshes as Groundwater Buffers for Development: A Survey of South Carolina Salt Marsh Basins

Frontiers in Water ◽

10.3389/frwa.2021.770819 ◽

2021 ◽

Vol 3 ◽

Author(s):

Alicia M. Wilson ◽

Meghan Shanahan ◽

Erik M. Smith

Keyword(s):

South Carolina ◽

Salt Marshes ◽

Tidal Creek ◽

Coastal Development ◽

Nutrient Concentrations ◽

Nitrogen And Phosphorus ◽

Dissolved Nitrogen ◽

Total Dissolved Nitrogen ◽

Groundwater Samples ◽

Linear Correlations

Salt marshes serve as zones of intense groundwater mixing and reaction between freshwater uplands and estuaries. This raises the question of whether the impacts of upland development on nutrient and carbon species can be transmitted through salt marshes via groundwater, or whether salt marshes can buffer estuarine waters from coastal development. We sampled groundwater from fifteen tidal creek basins in South Carolina to test for compositional differences associated with development and marsh width. Groundwater samples from near creekbanks and below freshwater uplands were analyzed for salinity, total dissolved nitrogen and phosphorus, and dissolved organic carbon. Analyses revealed significantly higher TDN and TDP concentrations in creekbank samples from developed watersheds, independent of the season. Analyses of upland samples revealed significantly lower DOC concentrations in developed uplands, again independent of season. These results support the hypothesis that development can affect groundwater compositions in coastal groundwater and therefore may affect coastal nutrient and carbon fluxes. However, results also revealed significant linear correlations between marsh width, salinity, and nutrient concentrations in some marshes. These results suggest that salt marshes can act as buffers for development, and specifically suggests that the buffering capacity of salt marshes increases with width. Narrow or trenched salt marshes are far less likely to be effective buffers.

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