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ŠUMARSKI LIST 1-2/1987 str. 19     <-- 19 -->        PDF

Sulphur Concentrations in Leaves of Some Forest Tree Species in Istria
and Hrvatsko Primorje


Investigations of the influence of SOj on sulphur content in Austrian and
aleppo pine needles and leaves of some autochtonous tree species at various distances
from the pollution source were carried out.

Concentrations of sulphur in assimilation organs of the examined species differed
among each other. The greatest relative content of this element was found in
leaves of flowering ash, the lowest in needles of Austrian pine.

Concentrations of sulphur differed according to age of the analysed organs.
As young leaves contain a rather high content of this bioelement, tehy can´t be
used as control for influence of SOj on forest trees.

For this purpose, we recommend collecting needles after the termination of
vegetation period, and leaves of the broad-leaved species before the leaves become
yellow. The Austrian pine plantations that ere placed up to 10 km from
the SO^ pollution source contained more sulphur in needles than the plantations
at over 22 km from the pollutant.

In the S02- pollutant environment, serious mechanical damage of the needles
and leaves was found in the investigated species. In this respect the pubescent oak
exibited less susceptibility than the examined conifer species and flowering ash.

The correlation between the S-concentration determined by the turbidimetric
and conductometric methods was practically complete, and the determined differences
were statistically insignificant.

The increase in SOj content in the atmospere and of S in assimilation organs
did not considerably influence the concentrations of the other elements in the plant