Effects of a long-term heavy-metal pollution on Scots pine forests

In this study the results of a 15-year long monitoring survey on heavy metals in water at Lake Modrac were assessed using pollution indices of heavy metals, such as Heavy metal pollution index HPI, Heavy metal evaluation index HEI and the Degree of contamination CD. The results of the survey on heavy metal pollution of sediment conducted in 2015 were used as input data for the following pollution indices: Concentration factor , Pollution load index PLI, Enrichment factor EF, Index of geo-accumulation Igeo, Ecological risk factor , Potential ecological risk index to the water-body, RI. The results showed a good correlation and the lake sediment was characterized as polluted. Enrichment factors and indices of geo-accumulation of heavy metals were indicated as very high enriched in the sediment, and have been identified as an anthropogenic source of pollution. Cumulative presence in the sediment is assessed through the pollution index, RI, and has been assessed as moderate ecological risk to the lake water-body. The application of pollution indices presents a valuable tool in assessing the long-term pollution status of Lake Modrac.

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Seventy-year history of management using low-intensity harvesting methods: weak impact on biodiversity of hemiboreal Scots pine forests

Canadian Journal of Forest Research ◽

10.1139/cjfr-2020-0102 ◽

2020 ◽

Vol 50 (12) ◽

pp. 1268-1280

Author(s):

Tea Tullus ◽

Reimo Lutter ◽

Tiina Randlane ◽

Andres Saag ◽

Arvo Tullus ◽

...

Keyword(s):

Species Richness ◽

Scots Pine ◽

Vascular Plants ◽

Forest Regeneration ◽

Lichen Species ◽

Pine Forests ◽

Low Intensity ◽

Management History ◽

Scots Pine Forests

Less intensive harvesting methods (e.g., selection cutting, shelterwood cuttings) are recommended as alternatives to clearcutting for maintaining mature forest biodiversity in the process of forest regeneration. However, the long-term impact of low-intensity harvesting methods has rarely been studied. Our aim was to clarify the long-term effects of repeated selective cutting, thinning, and shelterwood cutting on the richness, abundance, and species composition of vascular plants, bryophytes, and lichens in Scots pine forests (Pinus sylvestris L.). Data were collected from 25 mature stands located in dry Podzols in southwestern Estonia with a known management history for the last 70 years. Altogether, 35 vascular plant, 41 bryophyte, and 78 lichen species were recorded, including five species with conservational value. Generally, the management history was not related to species richness, except a negative correlation with the species number of epiphytic lichens on conifer trees. In addition, the abundance of two lichen species from the genus Chaenotheca was lower in more frequently managed stands. Species richness and composition were most strongly affected by soil pH and light conditions. We conclude that long-term, low-intensity harvesting of Scots pine forests on nutrient-poor Podzols maintains suitable habitats for vascular plants, bryophytes, and lichens, confirming its suitability for sustainable forest regeneration.

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