The objectives of this project are to quantify the seasonably variable timing among meteoric precipitation, groundwater recharge, and groundwater temperature. Hypotheses are: 1. Because of the karst-like characteristics of the aquifers in N04d (and by extension, the entire region), recharge will be rapid during moderately large precipitation events where fractures are enlarged by dissolution and therefore highly conductive, except during the most active part of the growing season. 2. The recharge efficiency of the aquifers will be spatially variable, with highest hydraulic conductivity (because of solution enlargement of fractures) near the riparian zone. 3. Groundwater temperature will vary continuously over the year and also demonstrate abrupt changes after recharge-effective precipitation events when the precipitation temperature is different from the groundwater temperature. Because the aquifers are merokarst and recharge is rapid, data are recorded at high frequency (5 minute intervals).
Record groundwater level and groundwater temperature to study groundwater recharge patterns.
Location of Sampling Stations: Selected wells (usually 3-5Mor, 3-5-1More, 4-6Mor, 4-6Eis1, 4-6Eis2, 4-2Mor). Sensors may be moved for special projects.
Frequency of Sampling: every 5 minutes
Variable Measured: temperature (°C), water pressure (m), air pressure (psi)
Field Methods: Remove loggers carefully from the well. Store in Styrofoam sleeves out of direct sunlight. Download data onto Solinst Leveloader. Measure and record the depth to water in the well using an E-line. Clear sensor of data. Check knots on the doubled nylon string before redeploying sensor.
Laboratory Methods: Transfer data from Solinst Leveloader onto computer using Leveloader and/or Levelogger software. Perform barometric compensation correction in the software. Save software generated files and also export uncompensated and compensated cvs files. In Microsoft Excel, use elevation of the measuring point on the wells and the depth-to-water measurement taken just before re-deploying sensor to calculate groundwater elevation in units of meters above mean sea level. Delete data recorded while sensor was out of the well. Plot results of water level elevation and temperature, and compile into annual data sets.
Form of Data Output: Excel file. Variables included are as follow:
Date: Date and time of measurement
Elevation: Groundwater elevation above mean sea level (m amsl)
Temperature: Groundwater temperature, °C.
Missing data for groundwater elevation and temperature are blank.
Summary of All Changes: Software: Leveloader 1.02 (2003-2015), Levelogger 18.104.22.168 (2003-2015), Levelogger 4.1.1 (2011-2015), Levelogger 4.2.0b3 (2015-2017), Levelogger 4.3.0 (July 2017 – present): Sensors: Barologger 3001LT, F5, M1.5 (4-6 Mor, 2003; 3-5Mor, 2003-2014); Levelogger Model 3001LT, F15, M5, LL01 (4-6Mor, 2003); Levelogger Model 3001LT, F15, M5, LL02 (4-6Mor, 2004; 3-5Mor, 2004-2010; 2-4Mor, 2010; 2-5Mor, 2010; 3-5Mor, 2010-2014); Levelogger Model 3001LT, F15, M5, LL03 (3-5-1Mor, 2004-2010); Barologger Gold (3-5Mor, 2015-present); Levelogger Gold (3-5Mor, 2015-2017); Levelogger Gold (4-6Eis1, 2015-present); Levelogger Gold (4-6Eis2, 2015-present); Levelogger Gold (4-2Mor, 2015-present); Levelogger Edge (3-5Mor, 2017-present).
Note to all of the 2017 wells: During 2017, beginning in July, a tracer test was performed at the field site. Because of the dyes in the wells, the data from the pressure transducers could not be downloaded for a long period of time, and water levels were not measured with the E-line. Therefore, the data were extrapolated and may demonstrate larger error than in other times.
2015-2016: For 2015 and 2016 data at well 3-5Mor, BL temp used a different equipment, which may cause the time a minute behind or ahead with the datatime used for the other two variables. The date/time from BL were listed in comment column. MS student’s thesis work
2010: Part of 2010 data are collected by MS student - Mikhail Tsypin (two wells). Wellname OW2-4Mor were collected from 7-10-2010 to 10-10-2010; and wellname OW2-5Mor data are only from 5-17-2010 to 7-10-2010. Tsypin, Mikhail, 2011, Dissolved inorganic carbon in soil and shallow groundwater, Konza Prairie LTER Site, NE Kansas, USA. MS thesis, Dept. of Geology, University of Kansas, 114 pages. Tsypin, M., and Macpherson, G. L. (2012). The effect of precipitation events on inorganic carbon in soil and shallow groundwater, Konza Prairie LTER Site, NE Kansas, USA. Applied Geochemistry, 27(12), 2356-2369. doi:10/1016/j.apgeochem.2012.07.008
Quality Assurance: Sensors are checked for accuracy before initial deployment. Water-level accuracy is tested in a 3.05 m (10 ft) clear plastic pipe partially filled with water. Water-temperature accuracy is tested using Digi-Sense thermocouple thermometer (Type T) that has a resolution of 0.1°C and accuracy of ±0.2% of the reading.
Instrumentation: Solinst unvented Leveloggers and Barologger (pressure transducers).
For additional metadata information see: http://lter.konza.ksu.edu/sites/default/files/DC.pdf
For additional methods information see: http://lter.konza.ksu.edu/sites/default/files/MM.pdf