A. Dieffenbach et al., IN-SITU SOIL SOLUTION CHEMISTRY IN AN ACID FOREST SOIL AS INFLUENCED BY GROWING ROOTS OF NORWAY SPRUCE (PICEA-ABIES [L.] KARST), Plant and soil, 192(1), 1997, pp. 57-61
A new approach for non-destructive monitoring of soil solution chemist
ry in high spatial and temporal resolution for rhizosphere studies is
presented. In a 5 x 10 mm grid, 30 micro suction cups (01mm) were inst
alled in a rhizotron with Norway spruce (Picea abies [L.] Karst.) grow
ing in low pH B-horizon soil. Roots grew through the grid, closely pas
sing the suction cups. Soil solution composition before, during and af
ter root passage was determined. For K+ and Mg2+ a significant decreas
e of soil solution concentration near root tips and elongation zones w
as observed, indicating a marked uptake of these elements. Mg2+ concen
tration was also significantly lowered when the root system aged, sugg
esting that this ion might also be taken up in older parts of the root
system. No influence of growing roots was found on Na+-concentrations
.