Forests are the lungs of our planet and the most important ecosystems for the biosphere. They provide the atmosphere with oxygen, absorb a huge amount of carbon dioxide emitted by humans, animals and by industrial enterprises. Most atmospheric oxygen is provided by forests (the rest comes from the global ocean). Forests absorb around 30 bln t of carbon dioxide annually, transforming it into 20-23 bln t of organic matter. Mass deforestation and forest fires are dangerous as they could gradually change the composition of gases in the atmosphere. By exchanging gases, forests absorb a huge amount of harmful impurities and act as living filters. They purify the air, humidify it and release phytoncides that are beneficial for humans and animals. Forests are home to a vast number of living creatures, such as mammals, birds, insects and reptiles. They are also very popular places for people to visit and enjoy. However, over the last hundred years human pressure on forest ecosystems has increased significantly. Forests have been greatly damaged by logging to produce timber for commercial purposes (in some countries, logging is increasing 5-6% a year).
Woody plants play a major role in diagnosing the environmental impact of mining companies in terms of landscape change owing to their indicative properties. Broadleaved species demonstrate the strongest resistance to man-made pollution, while conifer species are much more sensitive to pollutants and the first to be damaged.
Polyus’ operating assets are mainly surrounded by coniferous trees, such as larch, fir and pine trees, so the conditions of these vital ecosystems are assessed as part of the annual monitoring.
Olimpiada Mine is located in the Yenisey Forestry Area of fir and mixed dark coniferous forests in Severo-Yeniseysky District. The area is mainly covered with spruce trees, blueberries and green moss as well as by fire-induced birch trees mixed with rare yernik (dwarf birch). 25 trial forest sites in the Olimpiada Mine area are monitored annually to assess the mine’s environmental impact. Specialists from the Forest Institute of the Siberian Branch of the Russian Academy of Sciences observe forest areas that experience high dust load, rehabilitated dumps, such as Tyryda Zolotaya open pit, as well as reference areas of primary and secondary forests (without any pronounced man-made impact). In 2019, thermal background was also assessed for the Olimpiada Mine based on satellite information, as Siberia’s vegetation cover is not only exposed to anthropogenic impact but also to natural environmental and climate changes. The results of the assessment allow us to promptly track changes in the status and dynamics of plant communities in Siberia, which is very important for remote areas (which may not always be reached by expeditions). This was the first time that Polyus carried out such a study.
The forests around Verninskoye are predominantly softwood and stone birch (Betula Lanata) covering rocky slopes. The landscape is dominated by Dahurian larch forests, mostly Larix gmelinii, with bushes mixing with alpine tundra vegetation. The environment is affected by its altitude above sea level. The forest stand is not dense; it is covered by green moss and sedge grass, with trees growing lopsided. The river valleys are home to fir, aspen, ash and chosenia forests. The indicative feature of the forests around the Irkutsk business unit is a very beautiful species of Siberian dwarf pine (Pinus pimula). Vast areas of steep mountain slopes are covered either by Siberian dwarf pine or by loose rock. The most common are larch forests with a shrub layer of wild rosemary, bog bilberry, black crowberry and mountain cranberry. The larch trees reach up to 15-20 m high, and a diameter of 40-50 or even up to 70 cm. They increase 2.5 cm in diameter over 10 years, occasionally up to 4 cm over 10 years.
The mine is located in the Aldan mountain middle taiga zone of the South Yakutian larch and pine province with a share of hardwood. Larch predominates on 80% of forested areas. Pine forests account for 10.6% of the region’s territory, pine wood makes up to 95% for timber harvesting. Willow, chosenia, ash and birch forests mixed with pine and larch are common around the settlement of Nizhny Kuranakh and the Bolshoy Kuranakh river valley. Aldan sees vegetation spreading over the river channel and on old dumps due to the unimpeded transfer of seeds from the surrounding vegetation community on the left bank of the Bolshoy Kuranakh river.
The Natalka mine is part of the Kolyma-Verkhoyansk larch woodland zone of the East Siberian taiga softwood subregion. The area is dominated by larch woodland and Siberian dwarf pine. Alpine tundra vegetation often occurs on the slopes of the mountains, and chosenia and ash forests as well as various marshes are common in the river valleys. As part of the mine environmental monitoring, five sample areas are monitored by phytogeographers for the condition of larch tree growth. In 2019, there was a substantial increase in the number of 2-3 year larch saplings up to 10 cm high as more than 80 plants aged 2-3 years old were spotted in the sample areas. Trees 4-10 m high prevail in the young larch forests and woodlands, with the shrub layer composed of various Far Eastern species of birch: dwarf birch, stone birch and willow. There is a lot of shrub including rosemary prostratus, rhododendron aureum, bog bilberry, and mountain cranberry. In Magadan Region, lopsided larch tree crowns are not uncommon due to unfavorable weather conditions, mainly frost and wind dehydration. Healthy trees are exposed to adverse weather impact as their buds often freeze. However, hardly any significant damage to the trunk resulting from earlier freezing of top buds was spotted on adult trees and on specimen higher than 2 meters on all samples areas of the Natalka mine, which led to the conclusion that mass freezing of buds is uncommon for the area.
Polyus’ mines plant hundreds of coniferous saplings every year during improvement works in spring. Forest regeneration by Polyus employees has become a tradition at Polyus Krasnoyarsk, Polyus Aldan and at HQ, which has been planting fir trees in Tula Region for several past years. But, clearly, the most important thing that Polyus does to protect forests is fire prevention. This ensures that mines are on the alert for wildfires in summer. Together with monitoring, this allows them to control the surrounding forests and to promptly prevent wildfires.