The effect of sampling frequency and strategy on water quality modelling driven by high-frequency monitoring data in a boreal catchment

Abstract. Many agriculture-dominated lowland water systems worldwide suffer from eutrophication caused by high nutrient loads. Insight in the hydrochemical functioning of embanked polder catchments is highly relevant for improving the water quality in such areas or for reducing export loads to downstream water bodies. This paper introduces new insights in nutrient sources and transport processes in a polder in the Netherlands situated below sea level using high-frequency monitoring technology at the outlet, where the water is pumped into a higher situated lake, combined with a low-frequency water quality monitoring programme at six locations within the drainage area. Seasonal trends and short-scale temporal dynamics in concentrations indicated that the NO3 concentration at the pumping station originated from N loss from agricultural lands. The NO3 loads appear as losses via tube drains after intensive rainfall events during the winter months due to preferential flow through the cracked clay soil. Transfer function-noise modelling of hourly NO3 concentrations reveals that a large part of the dynamics in NO3 concentrations during the winter months can be related to rainfall. The total phosphorus (TP) concentration and turbidity almost doubled during operation of the pumping station, which points to resuspension of particulate P from channel bed sediments induced by changes in water flow due to pumping. Rainfall events that caused peaks in NO3 concentrations did not results in TP concentration peaks. The rainfall induced and NO3 enriched quick interflow, may also be enriched in TP but retention of TP due to sedimentation of particulate P then results in the absence of rainfall induced TP concentration peaks. Increased TP concentrations associated with run-off events is only observed during a rainfall event at the end of a freeze–thaw cycle. All these observations suggest that the P retention potential of polder water systems is primarily due to the artificial pumping regime that buffers high flows. As the TP concentration is affected by operation of the pumping station, timing of sampling relative to the operating hours of the pumping station should be accounted for when calculating P export loads, determining trends in water quality, or when judging water quality status of polder water systems.

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High-frequency monitoring of surface water quality at the outlet of the Ibrahim River (Lebanon): A multivariate assessment

Ecological Indicators ◽

10.1016/j.ecolind.2019.04.061 ◽

2019 ◽

Vol 104 ◽

pp. 13-23 ◽

Cited By ~ 14

Author(s):

Paula El Najjar ◽

Amine Kassouf ◽

Anne Probst ◽

Jean-Luc Probst ◽

Naim Ouaini ◽

...

Keyword(s):

Water Quality ◽

Surface Water ◽

High Frequency ◽

Surface Water Quality ◽

Frequency Monitoring

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The Water Quality of the River Enborne, UK: Observations from High-Frequency Monitoring in a Rural, Lowland River System

Water ◽

10.3390/w6010150 ◽

2014 ◽

Vol 6 (1) ◽

pp. 150-180 ◽

Cited By ~ 36

Author(s):

Sarah Halliday ◽

Richard Skeffington ◽

Michael Bowes ◽

Emma Gozzard ◽

Jonathan Newman ◽

...

Keyword(s):

Water Quality ◽

High Frequency ◽

River System ◽

Lowland River ◽

Frequency Monitoring

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Evolution of physicochemical species concentration in streams based on heavy rainfall event data obtained for high-frequency monitoring

RBRH ◽

10.1590/2318-0331.011616055 ◽

2016 ◽

Vol 21 (4) ◽

pp. 653-665

Author(s):

Rubia Girardi ◽

Adilson Pinheiro ◽

Edson Torres ◽

Vander Kaufmann ◽

Luis Hamilton Pospissil Garbossa

Keyword(s):

Water Quality ◽

Water Level ◽

Atlantic Forest ◽

High Frequency ◽

Heavy Rainfall ◽

Rainfall Event ◽

Heavy Rainfall Event ◽

Rainfall Events ◽

Frequency Monitoring ◽

Heavy Rainfall Events

ABSTRACT Studies carried out over short time intervals assist in understanding the biogeochemical processes occurring relatively fast in natural waters. High frequency monitoring shows a greater variability in the water quality during and immediately after heavy rainfall events. This paper presents an assessment of the surface water quality parameters in the Atlantic Forest biome, caused by heavy rainfall events. The work was developed in two fluviometric sections of the Concordia River watershed, located in the state of Santa Catarina, southern Brazil. The spatial distribution of land use shows the predominance of Atlantic Forest in fluviometric section 1 (FS1) and pasture, forestry, agriculture, and Atlantic Forest in fluviometric section 2 (FS2). In each selected heavy rainfall event, the evolution rainfall height, the water level, and physicochemical parameters of water were analyzed. In all events, the water quality changed due to the heavy rainfall. After the events, an increase in water level and turbidity in both fluviometric sections were detected. In addition, the ammonium ion concentration increased in the river, and the pH value and nitrate concentration decreased. The electrical conductivity presented different behavior in each section. The dissolved oxygen concentration increased in 19 of 27 events. The principal component (PC1) correlated with the turbidity in FS1, and it correlated with level, turbidity, and pH in FS2.

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High-frequency monitoring reveals nutrient sources and transport processes in an agriculture-dominated lowland water system

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-12-8337-2015 ◽

2015 ◽

Vol 12 (8) ◽

pp. 8337-8380 ◽

Cited By ~ 2

Author(s):

B. van der Grift ◽

H. P. Broers ◽

W. L. Berendrecht ◽

J. C. Rozemeijer ◽

L. A. Osté ◽

...

Keyword(s):

Water Quality ◽

High Frequency ◽

Water Discharge ◽

Water System ◽

Water Systems ◽

Transport Processes ◽

Rainfall Events ◽

Nutrient Sources ◽

Pumping Station ◽

Frequency Monitoring

Abstract. Many agriculture-dominated lowland water systems worldwide suffer from eutrophication caused by high nutrient loads. Insight in the hydrochemical functioning of embanked polder catchments is highly relevant for improving the water quality in such areas. This paper introduces new insights in nutrient sources and transport processes in a low elevated polder in the Netherlands using high-frequency monitoring technology at the outlet, where the water is pumped into a higher situated lake, combined with a low-frequency water quality monitoring program at six locations within the drainage area. Seasonal trends and short scale temporal dynamics in concentrations indicated that the NO3 concentration at the pumping station originated from N-loss from agricultural lands. The NO3 loads appear as losses with drain water discharge after intensive rainfall events during the winter months due to preferential flow through the cracked clay soil. Transfer function-noise modelling of hourly NO3 concentrations reveals that a large part of the dynamics in NO3 concentrations during the winter months can be related to rainfall. The total phosphorus (TP) concentration almost doubled during operation of the pumping station which points to resuspension of particulate P from channel bed sediments induced by changes in water flow due to pumping. Rainfall events that caused peaks in NO3 concentrations did not results in TP concentration peaks. The by rainfall induced and NO3 enriched quick interflow, may also be enriched in TP but this is then buffered in the water system due to sedimentation of particulate P. Increased TP concentrations associated with run-off events is only observed during a rainfall event at the end of a freeze–thaw cycle. All these observations suggest that the P retention potential of polder water systems is highly due to the artificial pumping regime that buffers high flows. As the TP concentration is affected by operation of the pumping station, timing of sampling relative to the operating hours of the pumping station should be accounted for when calculating P export loads, determining trends in water quality or when judging water quality status of polder water systems.

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