328
v. Banasova
distance of more than 1200 m from smelter, was still good. Leaf size was almost
equal to that of the control. Plants on this site flowered and produced seeds.
Deforested sites with changed soil chemistry are occupied by the invasive plant
species Calamagrostis epigeios with 80-100% cover. The cover of C. epigeios
stand was reduced to 50% on the sites with the highest contamination. C. epigeios
creates monotonous cover on the more contaminated areas. The negative impact
of Hg smelter operation occurred also in C. epigeios, although it belongs to the
tolerant and common plant species. A notable decrease in plant height occurred
on high contaminated sites. Development of panicles in the population was
influenced by pollution. On highly contaminated soils the frequency of
inflorescence decreased (Fig. 5). The panicle length showed no great differences
between plants growing on low or high contamination (Fig. 5). Sizes of panicles
are probably determined on a genetic basis and are practically the same near to
and at great distances from the smelter (Fig. 5).
The impact of high contamination occurs also in the aboveground biomass
values. A moderate stimulatory effect is shown by low Hg concentration, but
increasing Hg concentration decreased total aboveground biomass. (Fig. 5)
Weight of panicles decreased on highly contaminated soils. The decrease in
panicle weight occurring on less contaminated soils is probably affected by the
competition of higher cover of other plants.
The total biomass of the aboveground parts of C. epigeios decreased with
increasing Hg content (Fig. 5).
The damage symptoms showed some C. epigeios plants growing in the
communities near the smelter chimney. Deformed panicles, less seed production,
and bleaching are observed there (Fig. 6).
3.2.4
The Influence of the Smelter on Plant Communities
The original forests died out and were replaced by herbaceous vegetation in the
surroundings of the smelter. Some of the species belonging to the original forest
communities, such as Senecio fuchsii and Rubus idaeus, occurred also in the
degraded stands (Fig. 7). Both the cover of this species and species richness
decreased with increasing contamination (Fig. 8). Calamagrostis epigeios becomes the dominant species and creates monotonous cover, lacking any other
species. Diversity of plant cover increases where emission influence is slight, due
to invading species, i.e. Sambucus ebulus, or plants of original rock and forest
communities.
Depending on the distance from the smelter, degree of contamination and
landscape configuration, the following degradation stages have arisen:
First Stage. Beyond a distance of 3 km from the smelter, original stands of
Picea excelsa, Fagus sylvatica and Abies alba occur. The first damage symptoms
were visible on spruces and firs. The pines (Pinus sylvestris) did not manifest
•
Fig. 5. Number, length, biomass of Calamagrostis epigeios panicles, and total above-ground biomass
of C. epigeios in relation to Hg contamination of soil around the Hg smelter
v. Banasova
distance of more than 1200 m from smelter, was still good. Leaf size was almost
equal to that of the control. Plants on this site flowered and produced seeds.
Deforested sites with changed soil chemistry are occupied by the invasive plant
species Calamagrostis epigeios with 80-100% cover. The cover of C. epigeios
stand was reduced to 50% on the sites with the highest contamination. C. epigeios
creates monotonous cover on the more contaminated areas. The negative impact
of Hg smelter operation occurred also in C. epigeios, although it belongs to the
tolerant and common plant species. A notable decrease in plant height occurred
on high contaminated sites. Development of panicles in the population was
influenced by pollution. On highly contaminated soils the frequency of
inflorescence decreased (Fig. 5). The panicle length showed no great differences
between plants growing on low or high contamination (Fig. 5). Sizes of panicles
are probably determined on a genetic basis and are practically the same near to
and at great distances from the smelter (Fig. 5).
The impact of high contamination occurs also in the aboveground biomass
values. A moderate stimulatory effect is shown by low Hg concentration, but
increasing Hg concentration decreased total aboveground biomass. (Fig. 5)
Weight of panicles decreased on highly contaminated soils. The decrease in
panicle weight occurring on less contaminated soils is probably affected by the
competition of higher cover of other plants.
The total biomass of the aboveground parts of C. epigeios decreased with
increasing Hg content (Fig. 5).
The damage symptoms showed some C. epigeios plants growing in the
communities near the smelter chimney. Deformed panicles, less seed production,
and bleaching are observed there (Fig. 6).
3.2.4
The Influence of the Smelter on Plant Communities
The original forests died out and were replaced by herbaceous vegetation in the
surroundings of the smelter. Some of the species belonging to the original forest
communities, such as Senecio fuchsii and Rubus idaeus, occurred also in the
degraded stands (Fig. 7). Both the cover of this species and species richness
decreased with increasing contamination (Fig. 8). Calamagrostis epigeios becomes the dominant species and creates monotonous cover, lacking any other
species. Diversity of plant cover increases where emission influence is slight, due
to invading species, i.e. Sambucus ebulus, or plants of original rock and forest
communities.
Depending on the distance from the smelter, degree of contamination and
landscape configuration, the following degradation stages have arisen:
First Stage. Beyond a distance of 3 km from the smelter, original stands of
Picea excelsa, Fagus sylvatica and Abies alba occur. The first damage symptoms
were visible on spruces and firs. The pines (Pinus sylvestris) did not manifest
•
Fig. 5. Number, length, biomass of Calamagrostis epigeios panicles, and total above-ground biomass
of C. epigeios in relation to Hg contamination of soil around the Hg smelter