Denitrification rates in the sediments of Lake Memphremagog, Canada–USA

Saunders, Danielle L.; Kalff, Jacob

doi:10.1016/s0043-1354(00)00479-6

Cited by 117 publications

(76 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Air entering the soil inhibits denitrification (Patrick and Reddy 1976). Factors found to be correlated with denitrification rate in other studies, such as nitrate concentration (Davidsson and Leonardson 1998;Hasegawa and Okino 2004), temperature (Pribyl et al 2005) and organic matter content (Saunders and Kalff 2001) did not show significant correlations in our study. A direct effect of salinity on denitrification rates is not likely (Magalhães et al 2005;Fear et al 2007).…”

Section: Discussioncontrasting

confidence: 70%

“…Such a water regime would not only create opportunities for much wider zones with littoral vegetation, it would also create different conditions in the sediment with consequences for nutrient retention. Denitrification, for example, is strongly influenced by water level, organic matter content and presence of vegetation (Saunders and Kalff 2001). A full evaluation of the consequences of the restoration of a natural water level regime with wide littoral zones requires quantitative knowledge on the effects of water level fluctuations on nutrient cycling and retention in such zones.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Nutrient Cycling and Retention Along a Littoral Gradient in a Dutch Shallow Lake in Relation to Water Level Regime

Sollie

Verhoeven

2008

Water Air Soil Pollut

View full text Add to dashboard Cite

Littoral zones are characterized by gradients in depth and vegetation biomass, influencing nutrient retention capacity. A field experiment was conducted in a Phragmites australis dominated littoral zone to investigate nutrient retention and its effect on surface water quality. Measurements were done in mesocosms where water levels could be manipulated. Nutrient status was investigated along a gradient perpendicular to the shore during two growing seasons, one with a stable water level and one with a gradually decreasing water level. Nutrient concentrations in sediment, soil pore water and surface water were significantly lower in the vegetated than in the unvegetated zone. The negative correlations of nutrients in sediment and water, with nutrient contents of the vegetation suggest a direct effect of the vegetation. Nutrient uptake and biomass of the vegetation was higher in continuously flooded soils than in seasonally emerging sediments higher along the littoral gradient, probably due to the increased salinity in drained zones. Denitrification rate was highest in the unvegetated zone and was positively related to water level. Flooded littoral zones did result in a higher nutrient retention than drained zones. On small scale, for an optimal nutrient retention a fluctuating regime is not necessarily better suited than a stable water level, but on a larger scale it can substantially increase the width of the vegetated zone. It is important to optimize conditions for helophyte growth since the positive effect of vegetation on nutrient retention, at least at local scale, has been demonstrated in this study.

show abstract

Section: Discussioncontrasting

confidence: 70%

Section: Introductionmentioning

confidence: 99%

Nutrient Cycling and Retention Along a Littoral Gradient in a Dutch Shallow Lake in Relation to Water Level Regime

Sollie

Verhoeven

2008

Water Air Soil Pollut

View full text Add to dashboard Cite

show abstract

“…A smaller percentage of water also flows to Lake Poyang during the summer high-flow period. Thus, a proportion of the NO À 3 and NO À 2 loads from the upper Changjiang River could be retained or sequestered in these lakes through algal consumption and denitrification in the lake sediments (Windolf et al 1996;Svensson 1999;Saunders and Kalff 2001;Kaste and Dillon 2003), and the drastic increases in NO À 3 and NO À 2 observed towards the end of 1970s in the upper Changjiang were consequently buffered. The evidence supported these processes is (1) more than 18% of DIN inputs to Lakes Poyang and Dongting were retained or sequestrated (Table 2), and (2) NO À 3 and SRP concentrations of these lakes were significantly lower than those of the Changjiang mainstream ( Fig.…”

Section: Discussionmentioning

confidence: 99%

Long-term changes in nutrient concentrations of the Changjiang River and principal tributaries

Duan

Wang

2007

Biogeochemistry

View full text Add to dashboard Cite

show abstract

“…Denitrification (nitrate reduction) and nitrification (organic N oxidization) can both be increased as a function of temperature (Pfenning and McMahon, 1996;Saunders and Kalff, 2001;Carrera et al, 2003;Fdz-Polanco et al, 1994;Saidu, 2009). Thus, the effect of temperature on net nitrate release as a result of organic N mineralization may be partially counteracted by enhanced nitrate loss via denitrification and/or N immobilization.…”

Section: Effects Of Temperature On Transformations and Fluxes Of Docmentioning

confidence: 99%

Warming increases carbon and nutrient fluxes from sediments in streams across land use

Duan

Kaushal

2013

Biogeosciences

View full text Add to dashboard Cite

Rising water temperatures due to climate and land use change can accelerate biogeochemical fluxes from sediments to streams. We investigated impacts of increased streamwater temperatures on sediment fluxes of dissolved organic carbon (DOC), nitrate, soluble reactive phosphorus (SRP) and sulfate. Experiments were conducted at 8 long-term monitoring sites across land use (forest, agricultural, suburban, and urban) at the Baltimore Ecosystem Study Long-Term Ecological Research (LTER) site in the Chesapeake Bay watershed. Over 20 yr of routine water temperature data showed substantial variation across seasons and years. Lab incubations of sediment and overlying water were conducted at 4 temperatures (4 °C, 15 °C, 25 °C, and 35 °C) for 48 h. Results indicated: (1) warming significantly increased sediment DOC fluxes to overlying water across land use but decreased DOC quality via increases in the humic-like to protein-like fractions, (2) warming consistently increased SRP fluxes from sediments to overlying water across land use, (3) warming increased sulfate fluxes from sediments to overlying water at rural/suburban sites but decreased sulfate fluxes at some urban sites likely due to sulfate reduction, and (4) nitrate fluxes showed an increasing trend with temperature at some forest and urban sites but with larger variability than SRP. Sediment fluxes of nitrate, SRP and sulfate were strongly related to watershed urbanization and organic matter content. Using relationships of sediment fluxes with temperature, we estimate a 5 °C warming would increase mean sediment fluxes of SRP, DOC and nitrate-N across streams by 0.27–1.37 g m−2 yr−1, 0.03–0.14 kg m−2 yr−1, and 0.001–0.06 kg m−2 yr−1. Understanding warming impacts on coupled biogeochemical cycles in streams (e.g., organic matter mineralization, P sorption, nitrification, denitrification, and sulfate reduction) is critical for forecasting shifts in carbon and nutrient loads in response to interactive impacts of climate and land use change

show abstract

Denitrification rates in the sediments of Lake Memphremagog, Canada–USA

Cited by 117 publications

References 24 publications

Nutrient Cycling and Retention Along a Littoral Gradient in a Dutch Shallow Lake in Relation to Water Level Regime

Nutrient Cycling and Retention Along a Littoral Gradient in a Dutch Shallow Lake in Relation to Water Level Regime

Long-term changes in nutrient concentrations of the Changjiang River and principal tributaries

Warming increases carbon and nutrient fluxes from sediments in streams across land use

Contact Info

Product

Resources

About