Parts of the Thesis. Lysimeter Stations in Europe. Stations in Europe. Research Results. Overview. according to Classification.

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1 Lysimeter Stations and Soil Hydrology Measuring Sites in Europe Purpose Equipment Research Results Future Developments Johnstown Castle, Wexford/Ireland picture: provided by K. Richards Results of a 2004 survey/diploma thesis Christine Lanthaler christine.lanthaler@aon.at Parts of the Thesis Lysimeter Stations in Europe Basics of Soil Hydrology Lysimeter Types Stations in Europe Research Results Future Developments Concept for the Internet Platform Measuring Seepage methods water and probes samplers used in (SWS) the unsaturated zone Lysimeters (comparison of techniques) Comparison of types ERRORS Overview Classification according to Classification their vegeta- according tion type(s)/ to their only vegetation examples type(s) and countries/ Summary only examples Descriptions (tables) Statements Goal and reported target group in the Usability questionnaire Layout Contents Summary Example and general developments 2 1

2 Measuring Techniques Soil Hydrology soil water content: direct/destructive or gravimetric method soil samples Soil samples are taken in Wagna, 2004/07/26 picture: C. Lanthaler 3 Measuring Techniques Soil Hydrology soil water content: indirect/non-destructive methods measuring sensors TDR = Time Domain Reflectrometry dielectric constant TDR probes and pre-boring with extension tubes for installing probes in soil to avoid damaging the probe s rods according to IMKO 2003, pdf, modified 4 2

3 Measuring Techniques Soil Hydrology matric potential/suction: direct method tensiometer, piezometer negative pressure head of water is measured directly Principles of a tensiometer (above water table) and a piezometer (below water table) MARSHALL 1996, p. 30 Example of a tensiometer according to UMS 2003 a, modified 5 Measuring Techniques Soil Hydrology matric potential/suction: indirect method gypsum or porous blocks (electrical resistance method) matric potential must be derived indirectly from electrical conductivity/ soil water content Calibration curve of the gypsum block and block cast in rectangular shape with bared copper wire electrodes MARSHALL 1996, p

4 Measuring Techniques Soil Hydrology Scheme of probes installed in soil (Neuherberg) picture: C. Lanthaler, August 2004 Soil hydrological measuring profile (Wagna) picture: C. Lanthaler, August Soil Water Quality/Measuring Soil Hydrology soil solution/seepage water: suction cups suction plates vacuum is applied System of vacuum applied to suction cups, sampling bottles from UMS 2003 b, pdf, complemented LYSIMETER 8 4

5 What is a lysimeter? Lysimeters lysimeter = combination of Greek words: lusis = solution/germ.: Lösung and metron = measure/germ.: messen original aim: to determine transport and leaching losses of solutes; also used for determining actual evapotranspiration and groundwater recharge water balance! A lysimeter is a device that isolates a volume of soil or earth between the soil surface and a depth given and includes a percolating water sampling system at its bottom. 9 What is a lysimeter? Lysimeters soil is hydrologically isolated from surrounding soil, containers: filled with disturbed (artificially filled) or undisturbed (monolithic) bare soil or soil covered with natural or cultivated vegetation, seepage water is measured directly; vertical water movement is also to be determined 10 5

6 Purpose of Research Stations Use of lysimeters in different fields of research: (Soil) Hydrology, Soil Science, Hydrogeology, Water Economy water balance/evapotranspiration, monitoring seepage water/groundwater quality and quantity Agronomy, Agricultural Economy, Forest Economy nutrient and pesticide/herbicide leaching losses, water demand of agricultural areas Ecology, Environment Protection seepage water prediction of polluted sites, source term determination 11 Gravitation lysimeter Lysimeter Types percolating water is collected gravimetrically = gravitation lysimeter Lysimeter station of the LUA Essen (Waldfeucht) SUSSET et al., 2003 Principle sketch of a gravitation lysimeter MULLER

7 Weighable lysimeter (monolithic) Lysimeter Types lysimeters are either weighable Weighable lysimeter with built-in probes KLOTZ, SEILER 1998, p. 6 Weighing equipment (3 load cells) in Wagna picture: C. Lanthaler, August Non-weighable lysimeter (monolithic) Lysimeter Types or non-weighable Equipment of a measuring site including a non-weighable monolithic field lysimeter and soil hydrology measuring probes according to HARTL et al. 2001, p. 216, modified Modified monolithic field lysimeter, Petzenkirchen system according to FEICHTINGER in BAL 1992, p. 59, modified 14 7

8 Groundwater lysimeter Lysimeter Types an artificial groundwater level can be simulated = groundwater lysimeter GW level = variable Principle of a groundwater lysimeter with variable groundwater level KESSLER, MEISSNER and RUPP in BAL 2001, p Groundwater lysimeter Lysimeter Types or GW level = constant Hydraulic groundwater lysimeter Principle system of a groundwater lysimeter equipped with a device to control the constant groundwater level continuously DVWK 1980, p. 14 Principle of a hydraulic groundwater lysimeter (without electronic components for shallow water tables in mires/scotland) according to INGRAM, COUPAR, BRAGG

9 Large lysimeters Lysimeter Types large lysimeters/test areas size: 30 m² m²; trays or geomembrane filled with soil or substrate Luzerne Kompostsubstrat Hausmüll Sensoren B Lysimeterkeller C A D Drainagekies Drainage Sketch of the test field and a lysimeter container in Seibersdorf/Austria KRENN 2001 Large lysimeter in Seibersdorf/Austria picture: C. Lanthaler, August Seepage water samplers SWS Types SWS do NOT reach the earth s surface! SWS with applied vacuum (backfilled) Seepage water sampler (SWS) according to E. STENITZER EDER in BÖHM et al. 2002, p. 121, modified 18 9

10 Seepage water samplers SWS Types Capillary Wick Samplers (PCAPs) or Drain Gauge (monolithic) Capillary wick sampler in Villié-Morgon, France picture: provided by J.-G. Lacas, 2004 Capillary wick sampler, in: DECAGON, 2003/pdf 19 Seepage water samplers SWS Types Funnels, buckets, trays, collection segments/cans Collection segments and water samplers in a tunnel in Sinji Vrh/Slovenia ČENČUR CURK in BAL 2001, p. 128 Filled tray and collection vessel, installed in a forest near Jastrebarsko/Croatia picture: C. Lanthaler, October 2004 Seepage water sampler side view/czech Republic sketch provided by M. Florián 2004, modified 20 10

11 Weighable monolithic field lysimeters in Wagna Installing Lysimeters pictures: C. Lanthaler, August Classification Lysimeter Types Weighability (non-weighable/weighable) Groundwater connection Soil filling technique (monolithic/backfilled) Seepage water collection (gravimetric or not) Combined types (examples): Non-weighable backfilled gravitation lysimeter or Weighable monolithic groundwater lysimeter Large lysimeters/ test areas 22 11

12 Lysimeter Errors Natural hydraulic condition is disturbed, when a lysimeter or SWS is installed Island/oasis effects vegetative, hydrological and micro-climatical conditions have to be as highly as possible representative of the field Bypass fluxes cannot be determined in containers; lateral water transport is suppressed in a closed vessel Boundary effects at the borders plants are prevented from spreading; surface water may run in an uncontrolled way keep gaps (between cylinders) as small as possible; use larger vessels! 23 Lysimeter Errors Phenomena/boundary effects at the lysimeter bottom natural soil profile (capillaries) is interrupted; seepage water only occurs when hydraulic pressure exceeds air pressure (when pores are saturated) use several outlets to reduce dammed water! Disturbed profile when soil is artificially backfilled into lysimeters/sws, soil is mineralized due to aeration - higher nitrate concentration! investigate for longer periods, do not mix soil layers! Protect lysimeters against animals! The lysimeter that is built in best is the one you don t see!!! 24 12

13 General Statements Research Results Measurements at one position; lysimeter errors! Lysimeter studies Numerical water and nutrient transport models Investigation of land use change; balances 25 Lysimeter types The Survey 2930 vessels 2440 lysimeters 490 SWS 178 sites (ca.) in 18 countries operated by 117 institutions According to the survey

14 Lysimeter sites The Survey According to the survey Facts & Figures The Survey Still operating 2 lysimeters at Rothamsted Research (UK) since lysimeters at Limburgerhof (Germany) since 1927/1930 Largest number of vessels at one site 320 lysimeters in Szarvas (Hungary) 252 lysimeters at Limburgerhof (Germany) New lysimeters were built in at following sites (2004/2005) Wagna (Austria): 2 weighable monolithic field lysimeters & probes Munich/Freimann (Germany): 1 backfilled gravitation lysimeter Braunschweig-Völkenrode (Germany): 8 weighable backfilled lysimeters Villié-Morgon (France): 4 capillary wick samplers & probes Johnstown Castle, Wexford (Ireland): 75 non-weighable monolithic gravitation lysimeters Scotland (UK): seepage water samplers (5 plots) According to the survey

15 Internet Platform Lysimeter sites in Europe Research stations in Europe 29 Challenges Future Developments to investigate soil & groundwater protective cultivation systems and land use changes; to monitor the fate of pollutants in soil to determine water & nutrient balances; to calibrate and verify soil hydrological or solute transport models to improve measuring methods; to determine hydraulic parameters; to compare lysimeter data with data of surrounding undisturbed soil and to compare different soil types 30 15

16 Stations in Europe (Examples) Lysimeter and weather station Groß-Enzersdorf/Austria Lysimeter station (cellar) Jülich/Germany pictures: C. Lanthaler, April and August 2004 Lysimeter station (cellar) GSF Neuherberg/Germany 31 Stations in Europe (Examples) Lysimeter station Szarvas picture: provided by I. Zima Szaloki, 2004 Facility in Fagnières/France picture: provided by B. Nicolardot, 2004 Facility in Hirschstetten/Austria picture: C. Lanthaler, August 2004 Lysimeter station Jokioinen picture: provided by R. Lemola,