The reflectance of soil samples was measured in the wavelength range from 350 nm to 2500 nm, at 1-nm intervals, using a FieldSpec®Pro spectroradiometer (Analytical Spectral Devices, Inc., Boulder, CO, USA) with the attached Source Probe Mug-Lite®. Contact spectral measurements were calibrated with a white reference Spectralon® panel (Labsphere, Inc., North Sutton, NH, USA). Five reflectance spectra of each soil sample were collected and then averaged. The reflectance data were generalized into 10-nm intervals to provide a more concise dataset. Standard field characterization was performed at each location, soil profile was described to identify soil morphological properties of all horizons. Soils where classified according to Polish Soil Classification (SGP 2011) and World Reference Base (WRB 2007).
Physical and Chemical Properties of Soils
The samples were analysed in the laboratory of the Department of Soil Science and Remote Sensing of Soils, Adam Mickiewicz University in Poznań. They were air-dried, ground, and sieved through a 2 mm sieve. Clay (<2 μm) and silt (2–50 μm) fraction contents were determined using the hydrometer method (PKN, standard 04032, 1998) and sand (50-2000 μm) contents were calculated as the complement up to 100% . Soil organic carbon (Corg) content was based on sulfochromic oxidation of organic carbon with tube digestion, followed by titration of excess K2Cr2O7 with FeSO4´7H2O (Nelson and Somers, 1996). Cation exchange capacity (CEC) was calculated as a sum of total exchangeable bases (TEB) and exchangeable acidity (Hex). TEB was determined according to Mehlich method (TEA– triethanoloamine BaCl2) in modification of Kociałkowski and Ratajczak (1984) Hex (and ALex) according to Thomas (1982). Soil reaction was determined in 1:1 soil suspension in water and 1M KCl (pHH20, pHKCL) and carbonates content (CaCO3) according to Scheibler volumetric method.
Linked Geoportal WMS Layers
When you zoomed the map to the profile point - linear scale unit equal to 100 m - you can switch between linked base maps in order to understand natural conditions where the selected point are placed. You can use two layers: topographic map 1:10000 (Coordinate system “1965”) and orthophotomap of Poland. These layers are served with WMS protocol by geoportal.gov.pl. You can also switch to image map served by Googlemaps. KML and HTML page code preparation was supported with TNTmips Geomashup process (MicroImages, Inc.).