Current issue: 54(2)
A simple, manually-operated and easily portable device for sampling volumetric soil cores to a depth of 100 cm with a minimum soil disturbance is described. The device consists of a sample tube, a sampler and an extension tube. A dead blow nylon mallet is used to force the sampler into the soil and a small winch attached to an aluminium tube pulls the sampler from the soil. The total weight of the equipment (sampler, mallet and winch) is 18.5 kg and may be carried in the trunk of a small car. Sampling is easily done by one person in good physical condition but four-handed operation is recommended as more efficient. The sampling device has been in heavy use during the summers of 1993–95 when several hundred soil cores have been extracted on various sites all over Finland.
In soil profiles from a series of uplands of different site types bulk density, density of solids and porosity of soil were clearly related to soil organic matter content and its distribution in the soil profile. Soil organic matter contents were also strongly correlated to effective cation exchange capacity (CEC) and soil acidity. Site fertility was primarily related to the fine fraction (ø<0.06 mm) content in the C horizon and related properties (i.e. CEC). In the humus layer, the content of exchangeable bases and base saturation most strongly related to site fertility.
The PDF includes an abstract in English.
The study was made in the Ivalojoki and Oulankajoki valleys, consisting of terraces of well sorted sandy material aged 9500–300 B.P. The vegetation is characterized by dry and moderately dry forest types with Scots pine (Pinus sylvestris L.) as the dominant tree species. The study included: forest types, particle size and sorting of mineral horizons, thickness of horizons, amount of organic material, pH, electrical conductivity, and NH4OAc (pH 4.56) extractable Fe, Al, P, K, Mg, Mn and Zn concentrations. The principal aim was to study the interrelationships between all these properties with special reference to the age of the soil.
The results allowed a distinction to be made between the following categories: (1) features typical of podsolization (e.g. increase in leaching of Fe and Al with age of soil from the A2), (2) certain factors showing higher values in the north (Ivalo) than in the south (Oulanka), principally Fe and Mg, (3) declining trends in P, Mg, Mn and Zn concentrations with age, which may partly be due to the geological history, and (4) declining trends in amount of organic material and electrical conductivity with age, these both being factors arising from the geological history rather than from podzolization.
The PDF includes a summary in Finnish.