5/23/2015 The effect of planted tree species on the diversity of herbaceous vegetation in a reclaimed oil-shale opencast in Estonia Margus Pensa, Helen Karu, Aarne Luud, Elga Rull, and Riina Vaht Adapting Forest Management to Maintain the Environmental Services Koli

Estonian power industry 90% of Estonian electricity comes from burning of oil shale 5/23/2015

© Postimees Estonian power industry Because of that, per capita CO 2 emissions are very high 5/23/ t CO 2 yr -1

5/23/2015 Since 1918, the mining for oil shale has changed the landscape in an area of 430 km 2 Study sites were located in Narva opencast mine (59° 18’N, 27° 45’E) that occupies ca 70 km 2 Google

5/23/2015 Natural ecosystems of Narva opencast... Have been degraded to barren spoil... Which have been afforested by planting Scots pine (mainly) Reclamation started in 1960 and has been successful – forest productivity is higher than before mining.

5/23/2015 However, forest is not only a wood-producing factory but also a source of biodiversity Photo: Jaak Põder

5/23/2015 Examples of protected animal species found in Estonian oil-shale mining area Ursus arctos – Brown bear Canis lupus – Gray wolf Lynx lynx -- Lynx Pteromys volans – Flying squirrel Pandion haliaetus -- Osprey Aquila chrysaetos – Golden eagle Haliaeëtus albicilla – White-tailed eagle Ciconia nigra – Black stork

5/23/2015 Questions related to the reclamation of Narva opencast: Do planted tree species act as ecosystem engineers in reclaimed opencasts and create different habitats, so that herbaceous vegetation diverges at the later stages of succession according to the dominant tree species? (Pensa et al. 2004; 2008)

Pioneer stage of vegetation on recently (about five years ago) leveled mine spoil the Scots pine (Pinus sylvestris) chronosequence (10, 20, and 30 years old stands) 30-year-old planted stands dominated by larch (Larix sibirica and L. decidua) by silver birch (Betula pendula) 5/23/2015 Study sites in Narva opencast:

by alder (Alnus glutinosa and Alnus incana) Spontaneously developed stands in an area where the mine spoil had been left unplanted (natural stands) 5/23/2015 Study sites:

5/23/2015 Study sites Narva opencast

5/23/2015 Initial nutirent status of barren spoil in two oil-shale opencast in Estonia (Pensa et al Rest Ecol)

5/23/2015 The increase in tree biomass with time is... Broadleaved species

5/23/ negatively related to light conditions at ground level in Narva opencasts

5/23/2015 Differntiation in soil conditions with time Braodleaved species

5/23/2015 Differntiation in soil conditions with time Alder

5/23/2015 Richness of plant species – α, β, and γ- diversities in different forest stands in Narva opencast

5/23/2015 NMS ordination of herb species according to stand type Productivity of herbs Species richness Stand age

5/23/2015 Developmental patterns of herb layer in Narva opencast Alder Pioneer Pine30 Pine20 Pine10 Natural Larch Birch stress-tolerant species competitive species Calamagrostis epigeios Tussilago farfara Orthilia secunda Urtica dioica Festuca gigantea Calamagrostis arundinacea Productivity of herbs Species richness Stand age

5/23/2015 Conclusions Tree species have created recruitment limitations on the development of herb layer Broadleaved trees enhance the growth of herbs, while conifers supress it As different herb species are favoured by different tree species, the planting with various tree species ensures higher regional species richness

5/23/2015 Thank you!