title: Water quality and daily temperature cycle affect biofilm formation in drip irrigation devices revealed by optical coherence tomography.
abstract: Drip irrigation is a water-saving technology. To date, little is known about how biofilm forms in drippers of irrigation systems. In this study, the internal dripper geometry was recreated in 3-D printed microfluidic devices (MFDs). To mimic the temperature conditions in (semi-) arid areas, experiments were conducted in a temperature controlled box between 20 and 50°C. MFDs were either fed with two different treated wastewater (TWW) or synthetic wastewater. Biofilm formation was monitored non-invasively and in situ by optical coherence tomography (OCT). 3-D OCT datasets reveal the major fouling position and illustrate that biofilm development was influenced by fluid dynamics. Biofilm volumetric coverage of the labyrinth up to 60% did not reduce the discharge rate, whereas a further increase to 80% reduced the discharge rate by 50%. Moreover, the biofilm formation rate was significantly inhibited in daily temperature cycle independent of the cultivation medium used.
authors.affiliation: a Water Chemistry and Water Technology , Engler-Bunte-Institut, Karlsruhe Institute of Technology , Karlsruhe , Germany.
authors.forename: Jueying
authors.initials: J
authors.lastname: Qian
authors.affiliation: a Water Chemistry and Water Technology , Engler-Bunte-Institut, Karlsruhe Institute of Technology , Karlsruhe , Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Horn
authors.affiliation: b The Robert H. Smith Faculty of Agriculture, Food and Environment , The Hebrew University of Jerusalem , Rehovot , Israel.
authors.forename: Jorge
authors.initials: J
authors.lastname: Tarchitzky
authors.affiliation: b The Robert H. Smith Faculty of Agriculture, Food and Environment , The Hebrew University of Jerusalem , Rehovot , Israel.
authors.forename: Yona
authors.initials: Y
authors.lastname: Chen
authors.affiliation: b The Robert H. Smith Faculty of Agriculture, Food and Environment , The Hebrew University of Jerusalem , Rehovot , Israel.
authors.forename: Sagi
authors.initials: S
authors.lastname: Katz
authors.affiliation: a Water Chemistry and Water Technology , Engler-Bunte-Institut, Karlsruhe Institute of Technology , Karlsruhe , Germany.|c Institute of Functional Interfaces , Karlsruhe Institute of Technology , Eggenstein-Leopoldshafen , Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Wagner
mesh_terms: D057914:Agricultural Irrigation / Q000295:instrumentation*; D018441:Biofilms / Q000254:growth & development*; D057219:Biofouling / Q000517:prevention & control; D003889:Desert Climate; D056656:Lab-On-A-Chip Devices / Q000382:microbiology*; D008962:Models, Theoretical; D013696:Temperature; D041623:Tomography, Optical Coherence; D062065:Wastewater / Q000737:chemistry / Q000382:microbiology; D014872:Water Movements; D018508:Water Purification / Q000379:methods; D060753:Water Quality; D014881:Water Supply / Q000379:methods / Q000592:standards
chemical_list: D062065:Wastewater
keywords: Drip irrigation; biofilm formation; daily temperature cycle; microfluidic devices; optical coherence tomography