Neue Meßtechniken zur gleichzeitigen Bestimmung von Wassergehalt, Wasserspannung und verfügbaren Düngersalzen im Boden
1998
Paul, Wolfgang | Hilhorst, M. A. | Münstermann, Christian | Schmitz, Martin
德语. The four main readings of actual soil state are volumetric water content, tensiometric pressure, ion concentration in available water and temperature. The sensorics for these values is evaluated, especially the sensitivities of these measurements to standard influences met in practice as varying temperatures, soil types, soil moistures, salinities and densities. For the FD-sensor the mapping from permittivity to volumetric water content is improved, when temperature dependencies are included. An interesting and important step to selfcalibration regardless of soil type can be achieved by measuring at two frequencies. For conductivity measurements the bulk electrical conductivity can be transformed to salinity of pore water. This opens new possibilities for the assessment of fertilizer content in soil as well for plant nutrition as for pollutional washout risk. For equitensiometers the results show possibilities for improvments. The time response for the equitensiometers is ambiguous. With better sunstrate or ceramics this technique wil become a valuable tool. A penetrating stick measuring the four main states over various depths will give new possibilities for optimal inputs of water and fertilizer.
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