TY - JOUR A1 - Schmidinger, J. A1 - Barkov, V. A1 - Tavakoli, H. A1 - Correa, J. A1 - Ostermann, Markus A1 - Atzmueller, M. A1 - Gebbers, R. A1 - Vogel, S. T1 - Which and how many soil sensors are ideal to predict key soil properties: A case study with seven sensors N2 - Soil sensing enables rapid and cost-effective soil analysis. However, a single sensor often does not generate enough information to reliably predict a wide range of soil properties. Within a case-study, our objective was to identify how many and which combinations of soil sensors prove to be suitable for high-resolution soil mapping. On a subplot of an agricultural field showing a high spatial soil variability, six in-situ proximal soil sensors (PSSs) next to remote sensing (RS) data from Sentinel-2 were evaluated based on their capabilities to predict a set of soil properties including: soil organic carbon, pH, moisture as well as plant-available phosphorus, magnesium and potassium. The set of PSSs consisted of ion-selective pH electrodes, a capacitive soil moisture sensor, an apparent soil electrical conductivity measuring system as well as passive gamma-ray-, X-ray fluorescence- and nearinfrared spectroscopy. All possible combinations of sensors were exhaustively evaluated and ranked based on their predict KW - XRF KW - Soil KW - Remote Sensing KW - Precision agriculture PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613920 DO - https://doi.org/10.1016/j.geoderma.2024.117017 VL - 450 SP - 1 EP - 17 PB - Elsevier B.V. AN - OPUS4-61392 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sowoidnich, Kay A1 - Pätzold, Stefan A1 - Ostermann, Markus A1 - Sumpf, Bernd A1 - Maiwald, Martin T1 - Qualitative and quantitative soil characterization on an agricultural field using a portable shifted excitation Raman difference spectroscopy instrument N2 - Site-specific farmland management requires comprehensive information about the soil status to derive informed treatment decisions, e.g. for liming or fertilizer recommendations. Standard laboratory methods relying on sample collection have only limited ability to adequately capture the spatial variability of typical agricultural fields. Here, on-site analytical techniques with the potential to measure the soil properties on a substance-specific level and at the required spatial resolution could be very beneficial. Raman spectroscopy is a very promising technique for this purpose as it provides a molecular fingerprint of soil constituents. However, intrinsic soil fluorescence and daylight interference can be major issues masking characteristic Raman signals. Here, we apply an in-house developed portable shifted excitation Raman difference spectroscopy (SERDS) instrument based on a dual-wavelength diode laser emitting around 785 nm to effectively separate the Raman signals of soil from such interferences. SERDS investigations on a selected agricultural field in Germany demonstrate that the Raman spectroscopic signature of 9 soil minerals and organic carbon could successfully be separated from intense backgrounds. Using partial least squares regression against reference analyses, a successful prediction of the soil carbonate (R2 = 0.86, root mean squared error of cross validation RMSECV = 2.49%) and soil organic carbon content (R2 = 0.89, RMSECV = 0.32%) as important soil parameters is realized. The results obtained on-site with the portable instrument were confirmed by SERDS laboratory experiments of collected soil samples thus highlighting the capability and reliability of portable SERDS as promising and complementary tool for precision agriculture KW - XRF KW - Raman spectroscopy KW - Soil KW - SERDS KW - Precision agriculture PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634597 DO - https://doi.org/10.1039/d5an00178a SN - 0003-2654 VL - 150 IS - 13 SP - 2934 EP - 2944 PB - Royal Society of Chemistry (RSC) AN - OPUS4-63459 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erler, A. A1 - Riebe, D. A1 - Beitz, T. A1 - Löhmannsröben, H.-G. A1 - Leenen, M. A1 - Pätzold, S. A1 - Ostermann, Markus A1 - Wójcik, M. T1 - Mobile Laser-Induced Breakdown Spectroscopy for Future Application in Precision Agriculture—A Case Study N2 - In precision agriculture, the estimation of soil parameters via sensors and the creation of nutrient maps are a prerequisite for farmers to take targeted measures such as spatially resolved fertilization. In this work, 68 soil samples uniformly distributed over a field near Bonn are investigated using laser-induced breakdown spectroscopy (LIBS). These investigations include the determination of the total contents of macro- and micronutrients as well as further soil parameters such as soil pH, soil organic matter (SOM) content, and soil texture. The applied LIBS instruments are a handheld and a platform spectrometer, which potentially allows for the single-point measurement and scanning of whole fields, respectively. Their results are compared with a high-resolution lab spectrometer. The prediction of soil parameters was based on multivariate methods. Different feature selection methods and regression methods like PLS, PCR, SVM, Lasso, and Gaussian processes were tested and compared. While good predictions were obtained for Ca, Mg, P, Mn, Cu, and silt content, excellent predictions were obtained for K, Fe, and clay content. The comparison of the three different spectrometers showed that although the lab spectrometer gives the best results, measurements with both field spectrometers also yield good results. This allows for a method transfer to the in-field measurements KW - LIBS KW - Precision agriculture KW - Soil KW - Multivariate methods KW - Feature selection PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580777 DO - https://doi.org/10.3390/s23167178 VL - 23 IS - 16 SP - 1 EP - 17 PB - MDPI AG CY - Basel, Schweiz AN - OPUS4-58077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -