Microorganisms Collected from the Surface of Freshwater Lakes Using a Drone Water Sampling System (DOWSE)

Abstract

New tools and technology are needed to study microorganisms in freshwater environments. Little is known about spatial distribution and ice nucleation activity (INA) of microorganisms in freshwater lakes. We developed a system to collect water samples from the surface of lakes using a 3D-printed sampling device tethered to a drone (DOWSE, DrOne Water Sampling SystEm). The DOWSE was used to collect surface water samples at different distances from the shore (1, 25, and 50 m) at eight different freshwater lakes in Austria in June 2018. Water samples were filtered, and microorganisms were cultured on two different media types, TSA (a general growth medium) and KBC (a medium semi-selective for bacteria in the genus Pseudomonas). Mean concentrations (colony forming units per mL, or CFU/mL) of bacteria cultured on TSA ranged from 19,800 (Wörthersee) to 210,500 (Gosaulacke) CFU/mL, and mean concentrations of bacteria cultured on KBC ranged from 2590 (Ossiachersee) to 11,000 (Vorderer Gosausee) CFU/mL. There was no significant difference in sampling distance from the shore for concentrations of microbes cultured on TSA (p = 0.28). A wireless bathymetry sensor was tethered to the drone to map temperature and depth across the sampling domain of each of the lakes. At the 50 m distance from the shore, temperature ranged from 17 (Hinterer Gosausee, and Gosaulacke) to 26 • C (Wörthersee), and depth ranged from 2.8 (Gosaulacke) to 11.1 m (Grundlsee). Contour maps of concentrations of culturable bacteria across the drone sampling domain revealed areas of high concentrations (hot spots) in some of the lakes. The percentage of ice-nucleation active (ice+) bacteria cultured on KBC ranged from 0% (0/64) (Wörthersee) to 58% (42/72) (Vorderer Gosausee), with a mean of 28% (153/544) for the entire sample set. Future work aims to elucidate the structure and function of entire microbial assemblages within and among the Austrian lakes.

A Drone-Based Bioaerosol Sampling System to Monitor Ice Nucleation Particles in the Lower Atmosphere

“…Furthermore, sampling with well-defined waypoints (i.e., automatic approaching of GPS-points) could increase spatial resolution of flights with UASs. In one example, this technique was used to sample water with DJI Phantom 4 drones above freshwater lakes and analyze the resulting culturable microorganisms [59].…”

Tracking a Surrogate Hazardous Agent (Rhodamine Dye) in a Coastal Ocean Environment Using In Situ Measurements and Concentration Estimates Derived from Drone Images

“…Individual locations in close proximity to the ship were sampled by filling 50 mL conical tubes (Genesee Scientific #28-108) with ocean water. We utilized the DOWSE sampling system to retrieve the ocean water samples [15]. Samples were stored on board in the dark.…”

“…UASs have also been used in coral ecology [9], hydrography [10][11][12][13] and to track pathogens in the air [14]. Benson et al [15] developed a DrOne Water Sampling SystEm (DOWSE) to study microorganisms in freshwater habitats. This system This system consisted of a 3D-printed sampling device tethered to a drone, and was used to collect water samples at the surface of eight different lakes in Austria.…”

Aplicación de la fotogrametría con drones al control deformacional de estructuras y terreno

“…En primer lugar, se encuentran con seis artículos cada uno, Italia (13,14,15,16,17,18) y Austria (19,20,21,22,23,24), aunque bien es cierto que en el caso de Italia varios de ellos son referentes a la Presa Ridracoli (13,16,17). A continuación se sitúan China (25,26,27,28,29) y EEUU (30,31,32,33,34), siendo los norteamericanos los únicos que cuentan con un documento oficial "Monitoring Levees" (30) en el que se hace referencia explícita al uso de drones en la seguridad de presas.…”