ON THE ASSESSMENT OF SULPHUR DEPOSITION ON FORESTS
GROWING OVER THE AREAS OF INDUSTRIAL IMPACT
M. L. GYTARSKY, R. T. KARABAN and I. M. NAZAROV
Institute of Global Climate and Ecology, 20-B Glebovskaya St., 107258, Moscow, Russia
(Received 14 November 1995; accepted 10 October 1996)
Abstract. A method of calculation of sulphur deposition values on forests subject to long-term
industrial inﬂuence is presented. Investigations were conducted in the vicinities of nickel smelters
of Kola peninsula. Sulphur dioxide (SO
) is the major phytotoxicant emitted by these enterprises.
Depositions of sulphur were calculated on the basis of ground air layer pollution. To determine it a
mathematical model was applied. Field surveys of forest ecosystems response to air contamination
were carried out and areas of different forest damage degree were identiﬁed. More than 4300 km
the territory of Kola peninsula is under the impact of nickel enterprises. Average SO
over the area of slight damage to forests is about 20
. It corresponds to the critical level proposed
for forest ecosystems (UN ECE, 1993). Sulphur deposition over the area of slight damage varies from
for coniferous forests. For deciduous forests it is about 1.0 g/m
values are close to target loads for highly sensitive ecosystems (Nilsson et al., 1991), but they exceed
critical loads for the northern regions of Europe (Downing et al., 1993).
Key words: air pollution, critical levels, critical loads, forest damage assessment, industrial emissions,
Deposition of sulphur may cause both direct and indirect effects on forest ecosys-
tems. As a rule, the direct effects on forests are associated with visually determined
foliate damage with gaseous pollutant sulphur dioxide (SO
). It is emitted by
enterprises of all branches of industry, but most of all by metallurgical complexes
and thermoelectric power stations. SO
negative impact on plants has mainly been
studied as the relationship between the contaminant concentrations in surface air
layer and response of plants to them. The critical levels of sulphur dioxide have
been determined for forest ecosystems, natural vegetation and agricultural crops
(UN ECE, 1993).
The indirect effects of SO
and other contaminants are commonly related to soil
mediated inﬂuence on root systems of plants. Changes in chemical composition
and nutrition status of soils cause violations in normal growth and development of
plants that may result in their damage and decline. Consequencesof indirect effects
on forest ecosystems are well known and described elsewhere (De Vries, 1988).
Conceptions of critical and target loads of the pollutant deposition are applied for
assessments of indirect effects on forest ecosystems (Nilsson et al., 1991; Downing
et al., 1993). Calculations of critical loads are based on the acid neutralising
capacity of soils and the input and redistribution of sulphur and nitrogen among
the components of forest ecosystem (UN ECE, 1993; Downing et al., 1993).
Environmental Monitoring and Assessment 48: 125–137, 1997.
1997 Kluwer Academic Publishers. Printed in the Netherlands.