OREANDA-NEWS. December 11, 2013. Within the framework of an international forest renewal doctoral course, the Institute of Forestry and Rural Engineering of Estonian University of Life Sciences introduced the experience of oil shale quarry recultivation in Eesti Energias Narva quarry to lecturers, scientists, students, and practicians from Sweden, Finland, Estonia, Latvia, Iran, and France.

Mines are the backbone of Ida-Viru Countys industry and the source of the oil shale industrys raw material. Former open pits are conditioned either through afforestation, transformation into farmland, or the creation of a whole new use for the area in order to return them to the natural and living environment with dignity. Afforestation has been most widely used in recultivating Eesti Energias quarries. Mainly pine and birch are planted, but also alder and aspen.

Figuratively, excavation is followed by a green line because the mined area is continuously being conditioned. For instance, in the Aidu quarry, which was closed last year, the landscape is now covered by both 5- and 50-years-old forest.

The afforestation of depleted oil shale quarries has been quite successful in Estonia. Studies have been conducted here for several decades and the gained experiences definitely contribute to the further afforestation of oil shale quarries, said Doctor Marek Metslaid, the doctoral course organiser and Senior Research Fellow at the University of Life Sciences. As the process of restoring quarries as forest land has been monitored for decades, scientists have a plethora of material from which to draw conclusions, give recommendations, and also introduce the gathered knowledge on an international level.

According to Kalmer Sokman, Mineral Resources Environmental Manager at Eesti Energias environment services, the afforestation of quarries has been carried out in cooperation with scientists already for several decades. For us, it is important that the former quarry land obtains a new value. Scientists have an important role to play in successfully afforesting the areas, said Sokman.

Estonian scientists aimed to show foreign colleagues, via conditioned Narva quarry areas, how successfully cultivated trees have adopted the excavated landscape as their own. The test cultures established in Narva quarry under the guidance of Doctor Tatjana Kuznetsova, Research Fellow at the University of Life Sciences, were well-suited for this purpose. The research results have been published in several professional international peer-reviewed scientific journals. During the visit, scientists from the University of Life Sciences also reviewed the test areas with pine, spruce, and larch stands, established in the second half of the 1960s, where measurements have been taken already for 30 years.

The international doctoral course was conducted by the Institute of Forestry and Rural Engineering of the Estonian University of Life Sciences, the doctoral school Sustainable Management and Utilization of Forests of the Swedish University of Agricultural Sciences, and the Nordic forest renewal network EFINORD-SNS. In the Narva quarry, the course was hosted by Professor Andres Kiviste and course organiser and Senior Research Fellow Marek Metslaid, from the University of Life Sciences, who is also the Nordic forest renewal network coordinator at EFINORD-SNS.

Since the 1960s, 13 000 hectares of forest has been established in oil shale quarries. Seventy per cent of the planted trees are coniferous and 30% deciduous. In 2012, 95 ha of open pits were afforested. Eesti Energia orders afforesting works from RMK. Traditionally, Eesti Energias employees have organised forest planting bees; with the most recent having taken place in spring 2013, in cooperation with Nature Bus.