| Abstrakt: |
This paper examines sources of variation in the chemical quality of soil water collected during a 9-wk period (July to September 1981) with six tension lysimeters installed at a forest harvested site in central Finland. The soil was an iron podsol, and the lysimeters were installed to a depth of 25 cm, i.e., within the B horizon. Three lysimeters were installed at 2- to 3-m spacings in the center of two plots, some 200 m apart. The lysimeters were fitted with 6 cm long x 3 cm o.d. sintered glass cups of pore size 10 to 16 µm. Replicate samples, usually five, were drawn regularly each week with each lysimeter, using a tension pressure of ca. 42 kPa. The mean soil water tension at the 15- and 35-cm depths was 4.1 and 3.1 kPa, respectively. Chemical analysis (conductivity and H+], NH4+], PO43-], and K+] and Ca2+] ion concentrations) of the unfiltered samples was completed within 72 h of collection. |
