Epibenthic Algal Production and Community Respiration in the Sediments of Marion Lake

1969 ◽  
Vol 26 (8) ◽  
pp. 2003-2026 ◽  
Author(s):  
Barry T. Hargrave
Keyword(s):  
Oxygen Consumption ◽  
Particulate Matter ◽  
Oxygen Concentration ◽  
Sediment Cores ◽  
Day Length ◽  
Community Respiration ◽  
Oxygen Production ◽  
Algal Production ◽  
Undisturbed Sediment

Gross epibenthic algal production and benthic community respiration in Marion Lake, British Columbia, were measured during 1968 by following changes in dissolved oxygen over undisturbed sediment cores. No measurable chemical uptake of oxygen occurred during short-term experiments. Multiple regression analyses showed that in situ oxygen production by epibenthic algae was directly related to temperature, light, and community respiration and inversely related to day length. Mean weekly values of these variables were substituted into the regression to estimate annual gross algal production on sediment at various depths in Marion Lake. Photosynthetic efficiency ranged from 0.4 to 3.1% and increased with depth of water over the sediment. Sedimentary chlorophyll was stratified with highest concentrations in the upper few centimeters of sediment which corresponded to the depth of oxygen penetration.Measurements of in situ oxygen consumption showed that community respiration was related to temperature, oxygen concentration, and day length in a curvilinear manner. Oxygen uptake was minimal at midday and increased during the night. A multiple linear regression was derived, after suitable transformations, and mean weekly values of variables substituted to estimate annual community respiration.Bacterial respiration was measured as the difference in total community respiration when antibiotics were added to water over undisturbed sediment cores. Less than 30% of community oxygen consumption was inhibited by antibiotic treatment during the summer, whereas over 45% reduction occurred during the winter. Bacterial respiration was directly related to temperature and showed no significant correlation with oxygen concentration or other variables shown to affect community respiration. Macrofauna respired 33% of the total oxygen consumed by sediment cores during June, and epibenthic algae were estimated to account for 23% of community respiration. Net epibenthic algal production, calculated by correcting gross oxygen production for estimated algal respiration, was 85% of gross production during the summer.Annual carbon flux across the sediment in Marion Lake was estimated by comparing processes of carbon addition and removal. From previous studies, phytoplankton and macrophytes added 0.8 and 18 g C m−2 year−1. Organic particulate matter from the inlet stream, other than macroscopic debris, contributed 143 g C m−2 year−1 and average gross epibenthic algal production was 40 g C m−2 year−1. Community respiration consumed 57 g C m−2 year−1. An additional 143 g C m−2 year−1 was lost as particulate matter in the outlet stream and emerging insects could remove 1.3 g C m−2 year−1. Only 8 g C m−2 was estimated to accumulate below the aerobic surface–sediment layer annually.

Seasonal Changes in Oxygen Uptake by Settled Particulate Matter and Sediments in a Marine Bay

1978 ◽  
Vol 35 (12) ◽  
pp. 1621-1628 ◽  
Author(s):  
B. T. Hargrave
Keyword(s):  
Oxygen Consumption ◽  
Particulate Matter ◽  
Oxygen Uptake ◽  
Seasonal Changes ◽  
Sediment Cores ◽  
Late Summer ◽  
Sediment Traps ◽  
Chemical Oxidation ◽  
Organic Content ◽  
Carbon Equivalent

Oxygen consumption by material deposited in sediment traps suspended at different depths in a coastal marine bay was highest during summer. Seasonal changes in respiration (Formalin sensitive oxygen uptake) were significantly correlated with organic content and highest rates on a dry and organic weight basis occurred during summer. There was no consistent depth-related change in oxygen uptake but seasonal changes in respiration were significantly correlated over consecutive 10-m depth intervals between 20 and 60 m. Rates of respiration and chemical oxidation by undisturbed sediment cores from 60 m, which were maximum during late summer, were not related to seasonal changes in temperature or dissolved oxygen concentration. A 1–2-mo delay existed between the deposition of particulate matter with maximum rates of oxygen consumption and maximum oxygen uptake by bottom sediments. Similar seasonal changes and calculation of the carbon equivalent of sediment respiration, however, show that oxidation of settled organic matter is largely complete within the year of deposition. Key words: sedimentation, particulate matter, biological and chemical oxidation, marine sediments

scholarly journals Estimating the effect of burrowing shrimp on deep-sea sediment community oxygen consumption

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3309 ◽  
Author(s):  
Daniel Leduc ◽  
Conrad A. Pilditch
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Continental Slope ◽  
Deep Sea ◽  
Sediment Cores ◽  
Chemical Oxidation ◽  
Community Respiration ◽  
Deep Sea Sediment ◽  
Benthic Respiration ◽  
Infaunal Community

Sediment community oxygen consumption (SCOC) is a proxy for organic matter processing and thus provides a useful proxy of benthic ecosystem function. Oxygen uptake in deep-sea sediments is mainly driven by bacteria, and the direct contribution of benthic macro- and mega-infauna respiration is thought to be relatively modest. However, the main contribution of infaunal organisms to benthic respiration, particularly large burrowing organisms, is likely to be indirect and mainly driven by processes such as feeding and bioturbation that stimulate bacterial metabolism and promote the chemical oxidation of reduced solutes. Here, we estimate the direct and indirect contributions of burrowing shrimp (Eucalastacus cf. torbeni) to sediment community oxygen consumption based on incubations of sediment cores from 490 m depth on the continental slope of New Zealand. Results indicate that the presence of one shrimp in the sediment is responsible for an oxygen uptake rate of about 40 µmol d−1, only 1% of which is estimated to be due to shrimp respiration. We estimate that the presence of ten burrowing shrimp m−2 of seabed would lead to an oxygen uptake comparable to current estimates of macro-infaunal community respiration on Chatham Rise based on allometric equations, and would increase total sediment community oxygen uptake by 14% compared to sediment without shrimp. Our findings suggest that oxygen consumption mediated by burrowing shrimp may be substantial in continental slope ecosystems.

A Comparison of Benthic Microalgal Production Measured by C14 and Oxygen Methods

1973 ◽  
Vol 30 (2) ◽  
pp. 309-312 ◽  
Author(s):  
C. Hunding ◽  
B. T. Hargrave
Keyword(s):  
Dissolved Oxygen ◽  
Primary Production ◽  
Sandy Beach ◽  
Sediment Cores ◽  
Benthic Primary Production ◽  
Sources Of Error ◽  
Undisturbed Sediment

A comparison of estimates of benthic primary production on a sandy beach measured by in situ oxygen and laboratory C14 methods showed that both methods gave similar measures of the magnitude of production. Sources of error in each method are discussed. Measures of C14 uptake offer sensitivity when production is low, but when undisturbed sediment cores can be obtained, production is most easily measured by following changes in dissolved oxygen.

Effect of Ambient Oxygen Concentration on Measurements of Sediment Oxygen Consumption

1986 ◽  
Vol 43 (7) ◽  
pp. 1340-1349 ◽  
Author(s):  
P. J. Campbell ◽  
F. H. Rigler
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Concentration ◽  
Oxygen Depletion ◽  
Continuous Mixing ◽  
Ambient Oxygen ◽  
Hypolimnetic Oxygen ◽  
Sediment Oxygen Consumption ◽  
The Mean ◽  
Gas Tight

The disparity between hypolimnetic oxygen depletion in situ (HOD; independent of the ambient oxygen concentration), used to calculate sediment oxygen consumption (SOC) in one lake in southern Quebec, and measurements of SOC (dependent on the oxygen concentration) was minimal when experimental factors were controlled. Using gas-tight methods, SOC at 7–5 mg∙L−1 decreased by 75% when the oxygen concentration in respirometers fell to 3–1 mg∙L−1. With continuous mixing, the comparable decrease in SOC was 50%. Finally, the decrease was less than 30% and obvious only below 2 mg∙L−1 when the oxygen concentration was held constant in continuous flow respirometers. SOC results using the last procedure were within 10% of the mean SOC calculated indirectly from hypolimnetic oxygen budgets for the two previous years. Thus, mixing and a constant or slowly changing ambient oxygen concentration are required for realistic SOC measurements. In another experiment, oxygen uptake in water overlying the sediment accounted for a large and variable portion of the SOC, often more than 50%. Therefore, it may be impossible to separate the influence of the water and sediment on the HOD.

scholarly journals Stark Contrast in Denitrification and Anammox across the Deep Norwegian Trench in the Skagerrak

2013 ◽  
Vol 79 (23) ◽  
pp. 7381-7389 ◽  
Author(s):  
Mark Trimmer ◽  
Pia Engström ◽  
Bo Thamdrup
Keyword(s):  
Organic Matter ◽  
Oxygen Consumption ◽  
Sediment Cores ◽  
Anammox Bacteria ◽  
Ammonium Oxidation ◽  
Oxygen Penetration ◽  
Anammox Activity ◽  
Redfield Ratios ◽  
First Time

ABSTRACTEnvironmental anaerobic ammonium oxidation (anammox) was demonstrated for the first time in 2002, using15N labeling, in homogenized sediment from the Skagerrak, where it accounted for up to 67% of N2production. We returned to some of these original sites in 2010 to make measurements of nitrogen and carbon cycling under conditions more representative of thosein situ, quantifying anammox and denitrification, together with oxygen penetration and consumption, in intact sediment cores. Overall, oxygen consumption and N2production decayed with water depth, as expected, but the drop in N2production was relatively more pronounced. Whereas we confirmed the dominance of N2production by anammox (72% and 77%) at the two deepest sites (∼700 m of water), anammox was conspicuously absent from two shallower sites (∼200 m and 400 m). At the shallower sites, we could measure no anammox activity with either intact or homogeneous sediment, and quantitative PCR (16S rRNA) gave a negligible abundance of anammox bacteria in the anoxic layers. Such an absence of anammox, especially at one locale where it was originally demonstrated, is hard to reconcile. Despite the dominance of anammox at the deepest sites, anammox activity could not make up for the drop in denitrification, and assuming Redfield ratios for the organic matter being mineralized, the estimated retention of fixed N actually increased to 90% to 97% of that mineralized, whereas it was 80% to 86% at the shallower sites.

Phanerozoic Oxygen

2017 ◽  
Author(s):  
Donald Eugene Canfield
Keyword(s):  
Oxygen Consumption ◽  
Organic Carbon ◽  
Sea Level ◽  
Time Scale ◽  
Atmospheric Oxygen ◽  
Sea Level Change ◽  
Oxygen Production ◽  
Level Change ◽  
History Of ◽  
Geologic Processes

This chapter discusses the modeling of the history of atmospheric oxygen. The most recently deposited sediments will also be the most prone to weathering through processes like sea-level change or uplift of the land. Thus, through rapid recycling, high rates of oxygen production through the burial of organic-rich sediments will quickly lead to high rates of oxygen consumption through the exposure of these organic-rich sediments to weathering. From a modeling perspective, rapid recycling helps to dampen oxygen changes. This is important because the fluxes of oxygen through the atmosphere during organic carbon and pyrite burial, and by weathering, are huge compared to the relatively small amounts of oxygen in the atmosphere. Thus, all of the oxygen in the present atmosphere is cycled through geologic processes of oxygen liberation (organic carbon and pyrite burial) and consumption (weathering) on a time scale of about 2 to 3 million years.

Particulate matter variability in Kathmandu based on in-situ measurements, remote sensing, and reanalysis data

2021 ◽  
pp. 105623
Author(s):  
Stefan Becker ◽  
Ramesh Prasad Sapkota ◽  
Binod Pokharel ◽  
Loknath Adhikari ◽  
Rudra Prasad Pokhrel ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Particulate Matter ◽  
Reanalysis Data ◽  
In Situ Measurements

Effect of temperature on streambed vertical hydraulic conductivity

2013 ◽  
Vol 45 (1) ◽  
pp. 89-98 ◽  
Author(s):  
Weihong Dong ◽  
Gengxin Ou ◽  
Xunhong Chen ◽  
Zhaowei Wang
Keyword(s):  
Hydraulic Conductivity ◽  
Water Temperature ◽  
Sediment Cores ◽  
Effect Of Temperature ◽  
In Situ Tests ◽  
Effect Of Water ◽  
Vertical Hydraulic Conductivity ◽  
Increasing Trend ◽  
Streambed Vertical Hydraulic Conductivity

In this study, in situ and on-site permeameter tests were conducted in Clear Creek, Nebraska, USA to evaluate the effect of water temperature on streambed vertical hydraulic conductivity Kv. Fifty-two sediment cores were tested. Five of them were transferred to the laboratory for a series of experiments to evaluate the effect of water temperature on Kv. Compared with in situ tests, 42 out of the 52 tests have higher Kv values for on-site tests. The distribution of water temperature at the approximately 50 cm depth of streambed along the sand bar was investigated in the field. These temperatures had values in the range 14–19 °C with an average of 16 °C and had an increasing trend along the stream flow. On average, Kv values of the streambed sediments in the laboratory tests increase by 1.8% per 1 °C increase in water temperature. The coarser sandy sediments show a greater increase extent of the Kv value per 1 °C increase in water temperature. However, there is no distinct increasing trend of Kv value for sediment containing silt and clay layers.

scholarly journals Annual cycles of chlorophyll-<i>a</i>, non-algal suspended particulate matter, and turbidity observed from space and in-situ in coastal waters

Ocean Science ◽  
2011 ◽  
Vol 7 (5) ◽  
pp. 705-732 ◽  
Author(s):  
F. Gohin
Keyword(s):  
Particulate Matter ◽  
Continental Shelf ◽  
Mediterranean Sea ◽  
North Sea ◽  
Suspended Particulate Matter ◽  
Chlorophyll Concentration ◽  
Statistical Characteristics ◽  
Monitoring Networks ◽  
Suspended Particulate

Abstract. Sea surface temperature, chlorophyll, and turbidity are three variables of the coastal environment commonly measured by monitoring networks. The observation networks are often based on coastal stations, which do not provide a sufficient coverage to validate the model outputs or to be used in assimilation over the continental shelf. Conversely, the products derived from satellite reflectance generally show a decreasing quality shoreward, and an assessment of the limitation of these data is required. The annual cycle, mean, and percentile 90 of the chlorophyll concentration derived from MERIS/ESA and MODIS/NASA data processed with a dedicated algorithm have been compared to in-situ observations at twenty-six selected stations from the Mediterranean Sea to the North Sea. Keeping in mind the validation, the forcing, or the assimilation in hydrological, sediment-transport, or ecological models, the non-algal Suspended Particulate Matter (SPM) is also a parameter which is expected from the satellite imagery. However, the monitoring networks measure essentially the turbidity and a consistency between chlorophyll, representative of the phytoplankton biomass, non-algal SPM, and turbidity is required. In this study, we derive the satellite turbidity from chlorophyll and non-algal SPM with a common formula applied to in-situ or satellite observations. The distribution of the satellite-derived turbidity exhibits the same main statistical characteristics as those measured in-situ, which satisfies the first condition to monitor the long-term changes or the large-scale spatial variation over the continental shelf and along the shore. For the first time, climatologies of turbidity, so useful for mapping the environment of the benthic habitats, are proposed from space on areas as different as the southern North Sea or the western Mediterranean Sea, with validation at coastal stations.

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