Physical and chemical data for various lakes near Toolik Research Station, Arctic LTER. Summer 1983 to 1989.

Abstract: 

Decadal file describing the physical lake parameters recorded at various lakes near Toolik Research Station during summers from 1983 to 1989. Depth profiles at the sites of physical measures were collected in situ. Values measured included temperature, conductivity, pH, dissolved oxygen, Chlorophyll A, Secchi disk depth and PAR. Note that some sample depths also have additional parameters measured and available in separate files for water chemistry and primary production.

Project Keywords: 

Data set ID: 

10581

EML revision ID: 

7

Short name: 

ARC_Lakes_Physchem_1983-1989

DOI: 

10.6073/pasta/1f780cc1b9e31f58a87d72b8eb2693ea
People

Keywords: 

Arctic LTER keywords: 

Dates

Date Range: 

Wednesday, July 13, 1983 to Saturday, August 26, 1989

Publication Date: 

Thursday, December 12, 1985

Methods: 

The physical characteristics and chemistry of lake waters of the Arctic LTER were sampled at various locations either weekly, monthly or once per field season depending on the site and the year.

Until 1992 (inclusive) Dissolved O2 and temperature were measured using a YSI 57 Oxygen Meter, water calibrated. Temperature and conductivity were ready by a YSI model 33 conductivity meter. Carbonate alkalinity was titrated against pH depending on expected alkalinity (Wetzel and Likens, 1979). pH was measured electrometrically with a corning portable expanded standard pH buffer and corrected for the temperature of the sample.

Secchi disk depth was measured using a 22 cm Secchi disk, a black and white disk, that is lowered by hand into the water to the depth at which it vanishes from sight. This distance was then recorded. As there is only one depth for each site, the same Secchi depth is indicated for all depths measured at a particular site on a particular day. This measurement is generally made on the shady side of the boat and measured to the nearest 0.1 meters.

For measurements with notes indicating "Kipphut data":
Dissolved oxygen was measured by Winkler titration and samples were collected with a pump or Van Dorn bottle.
The Winkler Method is described as follows: The sample is treated with manganous sulfate, potassium hydroxide, and potassium iodide (the latter two reagents combined in one solution) and finally sulfuric acid. The initial precipitate of manganous hydroxide, Mn(OH)2 combines with the dissolved oxygen (DO) in the sample to form a brown precipitate, manganese(II) hydroxide, MnO(OH)2. Upon acidification, the manganese(II) hydroxide forms manganic sulfate which acts as an oxidizing agent to release free iodine from the potassium iodide. The iodine, which is stoichiometrically equivalent to the dissolved oxygen in the sample is then titrated with sodium thiosulfate. (“Methods for Chemical Analysis of Water and Wastes,” USEPA Publication #600/4-79-020, March, 1979. )
Kipphut data temperature measurements made with a mercury thermometer

Site specific information:

The following lakes have been used as experimental from 1983-1989:
Nutrient enrichment: N2, Toolik Limno Corral
Food web manipulations: Toolik Limno Corral
Reference lakes (no manipulations): Toolik, N2 Ref, N1**

In 1985 Lake N2 was separated into two parts with a dividing curtain, with half being fertilized at a rate calculated to be approximately 5 times the normal loading of nitrogen and phosphorous. The fertilizers used were ammonium nitrate and phosphoric acid. Site names "N2 Fert" indicates measurements from the fertilized side of the curtain (Measurements beginning July 5, 1985) and "N2 Ref" indicates the control (or reference) portion of the lake which was not fertilized. The curtain was removed in 2011. Prior to 1985 and after 2011 data from this lake was simply called Lake N2.

Site N3 data was obtained for consideration of fertilizing the lake (measured only once in May, 1985)

**Lake N1 data (from 1989) contained in this file is baseline data for lake N1 in which a fertilization experiment began in 1990.

Toolik Limno Bay was the site of an experiment testing the impact of human exploitation on arctic lakes. Corrals were 5 m in diameter and 5-6 m depth open to the sediment. Four limocorrals were deployed in 1983. These were treated with nutrient additions and fish addition (arctic grayling). Methods and experimental results and discussion are found in: O'Brien, W.J., A.E. Hershey, J.E. Hobbie, M.A. Hullar, G.W. Kipphut, M.C. Miller, B. Moller & J.R. Vestal. 1992. Control mechanisms of arctic lake ecosystems: a limn corral experiment. Hydrobiologia, 240: 143-188. In Book: Toolik Lake - Ecology of an Aquatic Ecosystem in Arctic Alaska. W.J. O'Brien (ed.), Kluwer Academic Publishers, Belgium.

Reference Citations: Wetzel, R.G., G.E. Likens. 1979. Limnological Methods. Saunders. Philadelphia.

Sites sampled.

Download a comma delimited (csv) or Excel file (includes metadata and data sheets).

Use of the data requires acceptance of the data use policy --> Arctic LTER Data Use Policy

To cite this data set see the citation example on the LTER Network Data Portal page for this data set.

Variables Details

(Variables names are in the first line/row of the CSV file and Excel data sheet.)
SortChem_#
  • Label: SortChem_#
  • Definition: Number used to identify samples - generally not used until later data but column remains with older data to enable comparison
  • Type: Nominal
  • Missing values: None specified
Site
  • Label: Site
  • Definition: Site Name: Name of the lake where measurements were taken. There are discrete sampling sites defined by water depth, generally they are at the point of maximum depth.
  • Type: Nominal
  • Missing values: None specified
Date
  • Label: Date
  • Definition: Date readings were taken on.
  • Type: Date/time
  • Date format: dd-mmm-yyyy
  • Missing values: None specified
Rounded Depth (m)
  • Label: Rounded Depth (m)
  • Definition: Depth of water measurement taken at starting from the surface as 0. This depth corresponds with data in other files (Nutrients, Chemistry)
  • Type: Physical quantity
  • Unit: meter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Hydrolab Depth
  • Label: Hydrolab Depth
  • Definition: Depth measured by hydrolab (where used), otherwise regular measured depth recorded
  • Type: Physical quantity
  • Unit: meter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Time_hr_dst
  • Label: Time_hr_dst
  • Definition: Exact time that each reading was recorded in Alaska Daylight Savings Time (1 hour ahead of Alaska Standard Time: if 13:00 DST than 12:00 AST)
  • Type: Nominal
  • Missing values: None specified
IBVSvr4a_V
  • Label: IBVSvr4a_V
  • Definition: Internal Battery Voltage of the Surveyor 4a Datalogger.
  • Type: Physical quantity
  • Unit: volt
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Temp_C
  • Label: Temp_C
  • Definition: Water temperature at depth.
  • Type: Physical quantity
  • Unit: celsius
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Cond_uS
  • Label: Cond_uS
  • Definition: Electrical conductivity of the water at depth.
  • Type: Physical quantity
  • Unit: microsiemenPerCentimeter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
pH
  • Label: pH
  • Definition: pH (opposite of the log of the hydrogen ion concentration).
  • Type: Physical quantity
  • Unit: dimensionless
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
DO_Sat
  • Label: DO_Sat
  • Definition: The percent saturation of dissolved oxygen at depth.
  • Type: Physical quantity
  • Unit: percent
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
DO_mg/l
  • Label: DO_mg/l
  • Definition: The concentration of dissolved oxygen at depth.
  • Type: Physical quantity
  • Unit: milligramPerLiter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
DO_umoles/L
  • Label: DO_umoles/L
  • Definition: The concentration of dissolved oxygen at depth.
  • Type: Physical quantity
  • Unit: micromolePerLiter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Chl_V
  • Label: Chl_V
  • Definition: In Vivo measurement of chlorophyll-a concentration.
  • Type: Physical quantity
  • Unit: volt
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Chl_ug/l
  • Label: Chl_ug/l
  • Definition: In Vivo measurement of chlorophyll-a concentration.
  • Type: Physical quantity
  • Unit: microgramPerLiter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
PAR_uEm2s
  • Label: PAR_uEm2s
  • Definition: PAR (photosynthetically active radiation) measured below the water surface.
  • Type: Physical quantity
  • Unit: microEinsteinPerMeterSquaredPerSecond
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
refPAR_uEm2s
  • Label: refPAR_uEm2s
  • Definition: PAR (photosynthetically active radiation) measured with Deck unit to correct for changes in ambient light.
  • Type: Physical quantity
  • Unit: microEinsteinPerMeterSquaredPerSecond
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Hydrolab
  • Label: Hydrolab
  • Definition: This field indicates which Hydrolab Datasonde instrument was used to take measurements
  • Type: Physical quantity
  • Unit: number
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Secchi_m
  • Label: Secchi_m
  • Definition: Measure of water transparency by depth a Secchi Disk is visible to.
  • Type: Physical quantity
  • Unit: meter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Notes
  • Label: Notes
  • Definition: Any additional information pertaining to measurements made for a particular depth, place and time.
  • Type: Nominal
  • Missing values: None specified
SortChem_#
  • Label: SortChem_#
  • Definition: Number used to identify samples - generally not used until later data but column remains with older data to enable comparison
  • Type: Nominal
  • Missing values: None specified
Site
  • Label: Site
  • Definition: Site Name: Name of the lake where measurements were taken. There are discrete sampling sites defined by water depth, generally they are at the point of maximum depth.
  • Type: Nominal
  • Missing values: None specified
Date
  • Label: Date
  • Definition: Date readings were taken on.
  • Type: Date/time
  • Date format: dd-mmm-yyyy
  • Missing values: None specified
Rounded Depth (m)
  • Label: Rounded Depth (m)
  • Definition: Depth of water measurement taken at starting from the surface as 0. This depth corresponds with data in other files (Nutrients, Chemistry)
  • Type: Physical quantity
  • Unit: meter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Hydrolab Depth
  • Label: Hydrolab Depth
  • Definition: Depth measured by hydrolab (where used), otherwise regular measured depth recorded
  • Type: Physical quantity
  • Unit: meter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Time_hr_dst
  • Label: Time_hr_dst
  • Definition: Exact time that each reading was recorded in Alaska Daylight Savings Time (1 hour ahead of Alaska Standard Time: if 13:00 DST than 12:00 AST)
  • Type: Nominal
  • Missing values: None specified
IBVSvr4a_V
  • Label: IBVSvr4a_V
  • Definition: Internal Battery Voltage of the Surveyor 4a Datalogger.
  • Type: Physical quantity
  • Unit: volt
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Temp_C
  • Label: Temp_C
  • Definition: Water temperature at depth.
  • Type: Physical quantity
  • Unit: celsius
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Cond_uS
  • Label: Cond_uS
  • Definition: Electrical conductivity of the water at depth.
  • Type: Physical quantity
  • Unit: microsiemenPerCentimeter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
pH
  • Label: pH
  • Definition: pH (opposite of the log of the hydrogen ion concentration).
  • Type: Physical quantity
  • Unit: dimensionless
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
DO_Sat
  • Label: DO_Sat
  • Definition: The percent saturation of dissolved oxygen at depth.
  • Type: Physical quantity
  • Unit: percent
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
DO_mg/l
  • Label: DO_mg/l
  • Definition: The concentration of dissolved oxygen at depth.
  • Type: Physical quantity
  • Unit: milligramPerLiter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
DO_umoles/L
  • Label: DO_umoles/L
  • Definition: The concentration of dissolved oxygen at depth.
  • Type: Physical quantity
  • Unit: micromolePerLiter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Chl_V
  • Label: Chl_V
  • Definition: In Vivo measurement of chlorophyll-a concentration.
  • Type: Physical quantity
  • Unit: volt
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Chl_ug/l
  • Label: Chl_ug/l
  • Definition: In Vivo measurement of chlorophyll-a concentration.
  • Type: Physical quantity
  • Unit: microgramPerLiter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
PAR_uEm2s
  • Label: PAR_uEm2s
  • Definition: PAR (photosynthetically active radiation) measured below the water surface.
  • Type: Physical quantity
  • Unit: microEinsteinPerMeterSquaredPerSecond
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
refPAR_uEm2s
  • Label: refPAR_uEm2s
  • Definition: PAR (photosynthetically active radiation) measured with Deck unit to correct for changes in ambient light.
  • Type: Physical quantity
  • Unit: microEinsteinPerMeterSquaredPerSecond
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Hydrolab
  • Label: Hydrolab
  • Definition: This field indicates which Hydrolab Datasonde instrument was used to take measurements
  • Type: Physical quantity
  • Unit: number
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Secchi_m
  • Label: Secchi_m
  • Definition: Measure of water transparency by depth a Secchi Disk is visible to.
  • Type: Physical quantity
  • Unit: meter
  • Maximum: Not specified
  • Minimum: Not specified
  • Precision: Not specified
  • Missing values:
    • . = Missing or Not Measured
Notes
  • Label: Notes
  • Definition: Any additional information pertaining to measurements made for a particular depth, place and time.
  • Type: Nominal
  • Missing values: None specified