Adaptation of Soil Physical Measurement Techniques for the Delineation of Mud and Lakebed Sediments at Neusiedler See

Abstract

For many water management issues of shallow lakes with non-consolidated sediments hydrographic surveys of the open water area and reed belt areas are required. In the frame of water management strategy for the steppe lake Neusiedler See, located between Austria and Hungary, a hydrographic survey was conducted. In the open water area (water depth ≥1 m) a sediment echosounder was used. To validate these measurements and to distinguish between water, mud, and sediment layers in the shallow lake and reed belt area additional measurements were needed. As no common standard methods are available yet, we developed a measurement system based on two commonly applied soil physical measurement techniques providing reproducible physical values: a capacitive sensor and a cone penetrometer combined with GNSS-positioning enable dynamic measurements of georeferenced vertical water-mud-bedsediments profiles. The system bases on site-specific calibrated sensors and allows instantaneous, in situ measurements. The measurements manifest a sharp water-mud interface by a sudden decline to smaller water content which is a function of the dielectric permittivity. A second decline indicates the transition to compacted mud. That is concurrently the density where the penetrometer starts registering significant penetration resistance. The penetrometer detects shallow lakebed-sediment layers. Within the lake survey this measurement system was successfully tested.

Characterization of sediment layer composition in a shallow lake: from open water zones to reed belt areas

“…The CSPS in a measuring system was designed for sediment layer delineation in shallow lakes, described in Kogelbauer et al (2013) (Fig. 1, left panel).…”

“…For this, software (GeneCon) was programmed in C# as the main part of the data acquisition system (see also Kogelbauer et al, 2013). Additional software (GenePost) was programmed for post processing.…”

“…Thus, a combination of soil physical sensors in a measuring system (combination of soil physical sensors, CSPS) was introduced in Kogelbauer et al (2013), providing continuous and georeferenced vertical profiles by in situ measurements. The system combined two commonly applied soil physical sensors, a capacitive sensor and a cone penetrometer (CP), synchronized with Global Navigation Satellite System with Real-Time Kinematic (GNSS RTK) positioning.…”

Characterization of sediment layer composition in a shallow lake: from open water zones to reed belt areas

“…The CSPS in a measuring system was designed for sediment layer delineation in shallow lakes, described in Kogelbauer et al (2013) The two sensors were combined with GNSS RTK positioning for dynamic vertical profile measurements with precise location information (x, y, z) of ±35 cm in overall accuracy.…”

Electromagnetic resonant properties of metal-dielectric-metal (MDM) cylindrical microcavities

“…In the visible and infrared range, as the wavelength increases, the penetration depth into the dielectric layer increases. At the same time, the ohmic loss of metal layers reduces reversely [22]. In particular, the ohmic loss is very low in the far infrared region, where it has a perfect reflection characteristic.…”