Relative binding strength for heavy metals for the groundwater-free floor space Brandenburg

This map is based on the legend units of the soil overview map with corresponding assignment of parameterised surface soil shapes. These represent a soil form society for each legend unit. The individual (surface) soil shapes were provided with parameters, including those for calculating the binding strength for heavy metals (see Hennings 2000, Chapter 2), which were determined by ground and laboratory tests. For this purpose, the corresponding parameters (soil type, humus content, pH value) were statistically derived for the same horizontal-substrate combinations (usually the median value). The sequence of horizontal-substrate combinations in the surface soil forms with their parameters (soil type, humus content, pH value, cap of the go horizon) formed the basis for calculating the relative binding strength against heavy metals (see Hennings 2000, link rule 7.1 to 7.3). For the heavy metals Fe(III), Hg, Pb, Cr(III), Cu, Al, Zn, Co, Ni, Cd and Mn, the following theme maps show the metal-specific relative binding strength for different depth ranges. This map represents the relative binding strength for the respective heavy metal in groundwater-free soil space or up to the upper limit of a go horizon or up to 2 m below GOF for the area soil forms involved. For this purpose, upper soil (including the support horizons up to 3 dm under GOF) and subsoil are treated separately. For the upper floor, the characteristic value is determined as above up to the step of the oral scaling. For the characteristic value of the following depth range up to 2 m below GOF or up to the upper limit of the go horizon per soil shape, the horizon with the highest pH-dependent binding strength is considered if this is > 3 dm thick. Otherwise, the directly hanging or lying horizon, weighted according to its thickness, is used to average the characteristic value that has the higher pH-dependent binding strength from these two horizons. Subsequently, surcharges for corresponding humus and clay contents are added. The parameters thus determined for upper and subsoil are added and ordinally scaled in levels 0 to 5, limiting the maximum value to 5. For different results for the soil forms of a legend unit, the dominating and subdominating ordinal scaled classified characteristics were given (see Hennings 2000, VKR 7.3).