02 Jul 2021

02 Jul 2021

Review status: this preprint is currently under review for the journal HESS.

Technical note: High accuracy weighing micro-lysimeter system for long-term measurements of non-rainfall water inputs to grasslands

Andreas Riedl, Yafei Li, Nina Buchmann, and Werner Eugster Andreas Riedl et al.
  • Department of Environmental Systems Science, ETH Zurich, Zurich, 8092, Switzerland

Abstract. Non-rainfall water (NRW), defined here as dew, hoar frost, fog, rime and water vapor adsorption, might be a relevant water source for ecosystems, especially during summer drought periods. These water inputs are often not considered in ecohydrological studies, because water amounts of NRW events are rather small and therefore difficult to measure. Here we present a novel micro-lysimeter (ML) system and its application which allows to quantify very small water inputs from NRW with an unprecedented high accuracy of ±0.25 g, which corresponds to ±0.005 mm water input. This is possible with an improved ML design paired with individual ML calibrations in combination with high-frequency measurements at 3.3 Hz and an efficient low-pass filtering to reduce noise level. With a set of ancillary sensors, the ML system furthermore allows differentiating between different types of NRW inputs: dew, hoar frost, fog, rime and the combinations among these, but also additional events when condensation on leaves is less probable, such as water vapor adsorption events. In addition, our ML system design allows to minimize deviations from natural conditions in terms of canopy and soil temperatures, plant growth and soil moisture. This is found to be a crucial aspect for obtaining realistic NRW measurements in short-statured grasslands. Our ML system has proven to be useful for high-accuracy, long-term measurements of NRW on short-statured vegetation like grasslands. Measurements with the ML system at a field site in Switzerland showed that NRW input occurred frequently with 127 events over 12 months, with a total NRW input of 15.9 mm. High average monthly NRW inputs were measured during summer months, suggesting a high ecohydrological relevance of NRW inputs for temperate grasslands.

Andreas Riedl et al.

Status: open (until 30 Aug 2021)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse

Andreas Riedl et al.

Data sets

Data from: High accuracy weighing micro-lysimeter system for long-term measurements of non-rainfall water inputs to grasslands Andreas Riedl

Andreas Riedl et al.


Total article views: 208 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
157 49 2 208 1 1
  • HTML: 157
  • PDF: 49
  • XML: 2
  • Total: 208
  • BibTeX: 1
  • EndNote: 1
Views and downloads (calculated since 02 Jul 2021)
Cumulative views and downloads (calculated since 02 Jul 2021)

Viewed (geographical distribution)

Total article views: 197 (including HTML, PDF, and XML) Thereof 197 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 29 Jul 2021
Short summary
The aim of this study was to develop a high accuracy micro-lysimeter system for the quantification of non-rainfall water inputs that overcomes existing drawbacks. The micro-lysimeter system had a high accuracy and allowed quantify and distinguish between different types of non-rainfall water inputs, like dew and fog. Non-rainfall water inputs occurred frequently at a Swiss alpine grassland ecosystem. These water inputs can be an important water source for grassland ecosystems during dry periods.