Complementary Use of Magnetometric Measurements for Geochemical Investigation of Light REE Concentration in Anthropogenically Polluted Soils

The purpose of this study was to use fast geophysical measurements of soil magnetic susceptibility (κ) as supplementary data for chemical measurements of selected light rare earth elements (REEs) in soil. In order to ensure diversity in soil conditions, anthropogenic conditions and types of land use, seven areas were selected, all located in regions subjected to past or present industrial pollution. Magnetometric parameters were measured using a selected magnetic sensor that was specially designed for measurements of soil cores and were used to classify collected soil cores into six distinctive types. The analysis of REEs concentrations in soil was carried out taking into account the grouping of collected soil samples based on the type of study area (open, forested and mountain), and additionally on the measured magnetometric parameters of collected soil cores. A use of magnetometric measurements provided different, but complementary to chemical measurements information, which allowed to obtain deeper insight on REEs concentrations in soils in studied areas.

Delineation of soil drainage class by electromagnetically measurements of soil magnetic susceptibility

<p>Soil has the most important role in agriculture. For instance, it prevents run off and also through its capacity for storing water, it acts as a water reservoir and provide water resources for plant roots. Water retention characteristics, nutrient holding capacities and solute transport of soil can affect its productivity. So, the plant growth is directly associated with the type of soil drainage. The prediction of soil drainage classes is one of the major steps in developing crop modelling. Among different physical and chemical soil health indicators, soil magnetic susceptibility (MS) is a promising factor for soil surveying because it is strongly affected by soil drainage class. The extremely reducing conditions, present in hydric soils, significantly enhance dissolution of soil ferrimagnetic minerals such as magnetite and maghemite. Since the MS of soils is mainly controlled by magnetite and maghemite concentrations, therefore MS values are typically very low in hydric, i.e. poorly drained or gleyed, soils.</p><p>The common method for measuring soil MS is utilizing handheld or laboratory MS meters (e.g. Bartington MS2 sensors). Such MS meters are required soil specimen to be available to directly measure MS of that specimen. So, their application is limited to surface soils, soil exposures and sampled soils. Other types of instruments for quickly measuring soil properties are electromagnetic induction (EMI) instruments. Although the EMI instruments were primarily invented to measure electrical conductivity (EC) of the topsoil for assessment of soil salinity, they can also be utilized to measure absolute value of the volume MS of the topsoil. These volume MS values can be further processed and inverted to reveal MS variations of soil layers.</p><p>In this study, 1-D inversion of volume MS data, measured by Geonics EM38 instrument in both vertical and horizontal magnetic dipole configurations, was done to calculate MS of selected soil profiles in order to delineate soil drainage classes. Besides, laboratory measurements of volume and mass-specific MS of soil core samples, collected in the same soil profiles, were done using Bartington MS2B and MS2C sensors. Results show a strong and positive relationship between MS values measured in the laboratory and volume MS recovered from inversion technique. Furthermore, the results reveal that MS in a well drained profile is higher than that of a poorly drained profile. Since EMI measurements of soil MS are done quickly in the field, then using surface MS measurements facilitates hydric soil delineation in a faster and more precise way.</p>

Analisis Suseptibilitas Magnetik Tanah dan Laju Evapotranspirasi di Desa Ranooha, Kecamatan Ranomeeto, Kabupaten Konawe Selatan

The problem in this research is how the magnetic susceptibility of the soil and the rate of evapotranspiration in Ranooha Village, Ranomeeto District, Konawe Selatan District. Soil magnetic susceptibility was measured using Bartington Susceptibility MS2B meter while evapotranspiration rate was measured using Lycimeter. Soil magnetic susceptibility analyzed consisted of three sampling points, each consisting of vegetation (grass) and non-vegetation (without grass) sites, with the same depth variations namely 0 cm, 10 cm, 20 cm, 30 cm, 40 cm and 50 cm. Each sample is coded V00, V10, V20, V30, V40, V50 for sampling at vegetation (grass) sites, and NV00, NV10, NV20, NV30, NV40, and NV50 for sampling at non-vegetation (without grass) sites. The measurement results show that variations in values of χLF range from a minimum value of 0.8 x 10-8 m3/ kg toa maximum value of 3.8 x 10-8 m3/ kg at point 1, minimum value of 0.8 x 10-8 m3/ kg up to a maximum value of 3.9 x 10-8 m3/ kg at point 2, and a minimum value of 0.9 x 10-8 m3/ kg up to a maximum value of 2.6 x 10-8 m3/ kg at point 3 for vegetation (grass). While variations in values of χLF rangefrom a minimum value of 1.7 x 10-8 m3/ kg to a maximum value of 2.4 x 10-8 m3/ kg at point 1, a minimum value of 1.6 x 10-8 m3/ kg up to a maximum value of 2.9 x 10-8 m3/ kg at point 2, and a minimum value of 1.6 x 10-8 m3/ kg up to a maximum value of 2.9 x 10-8 m3/ kg at point 3 for non vegetation (without grass). While the maximum rate of evapotranspiration occurs in November for 2018 which is 5.3 mm / day, while the maximum rate of evapotranspiration in 2019 also occurs in November which is 6.1 mm / day for vegetation (grass) sites. While the maximum rate of evapotranspiration occurs in October for 2018 which is 4.3 mm / day, while the maximum rate of evapotranspiration in 2019 occurs in November which is 5.7 mm / day for non-vegetation (without grass) sites