Propagation of native Arctic and alpine species with a restoration potential

Abstract

Arctic and alpine plant communities today are subject to an increasing frequency and intensity of anthropogenic disturbances. Good understanding of reproductive behaviour and regenerative capacity of native species is important in a restoration situation following human disturbance in Arctic and alpine vegetation. Seeds, bulbils or cuttings from 12 native Arctic and alpine species were collected from Longyearbyen in Svalbard and Dovre Mountain on the Norwegian mainland. Propagation ability was tested in greenhouse conditions. Seeds of Papaver dahlianum, Oxyria digyna, Luzula arcuata ssp. confusa, and bulbils of Bistorta vivipara all had more than 50 % germination. Dryas octopetala had less than 10 % germination. Both quick and slow germinators were identified among the tested species. Seed storage temperature (+4 °C, -1 °C and -20 °C) showed no overall effect on germination. The rooting capacity of cuttings from evergreen and deciduous species was tested. Arctostaphylos uvaursi, Empetrum nigrum ssp. hermaphroditum, Vaccinium vitis-idaea, Salix herbacea and S. polaris had more than 70 % rooting ability, while Dryas octopetala and Cassiope tetragona had less than 10 %. Saxifraga oppositifolia showed large variation in rooting ability, ranging from 20 -90 %. The species with high germination and rooting ability are used in an extended restoration experiment in the study areas.

Plant recruitment in the High Arctic: Seed bank and seedling emergence on Svalbard

“…Svalbard Dryas normally has low germinability (Cooper unpubl. ) but this increases under experimental warming (Wookey et al 1995) or exceptionally warm summers (Hagen 2002), suggesting a thermophilous response.…”

“…confusa, Saxifraga cernua and S. oppositifolia (Tables 2 and 3). Most have high fresh seed germination (Eurola 1972;Hagen 2002) suggesting regular reproduction by seeds in Svalbard. A higher number of species germinated in the field than in the greenhouse, indicating soil germination trials alone may underestimate seed bank species richness by up to 31% (see also Thompson et al 1997;Molau & Larsson 2000).…”

Germinability of arctic plants is high in perceived optimal conditions but low in the field

“…Emerging seedlings in both experiments were counted weekly for 5 weeks and subsequently every 3rd week; the experiment ran for 12 weeks. Seedlings remained in the pots to (Eurola 1972;Hagen 2002), Unimat in low-arctic Alaska (Bliss 1958), King Christian Island in the polar desert part of Canada (Bell and Bliss 1980), and from alpine Scandinavia (Söyrinki 1939) are given. Nomenclature follows the Pan Arctic Flora project (Elven 2007).…”

“…Germination conditions used to test factors influencing germination success in six arctic species in a stepwise design from perceived optimal to field conditions. Germination percentages of other studies Germination percentages were compiled from published studies of seeds collected in Svalbard (Eurola 1972;Hagen 2002); Unimat, northern Alaska (Bliss 1958); and King Christian Island, Northwest Territories (Bell and Bliss 1980). The germination percentages of B. vivipara (≡Polygonum viviparum L.) and Silene acaulis taken from Bliss (1958) are from seeds collected in alpine tundra in Wyoming.…”

“…It also has been assumed that there are energetic advantages of asexual reproduction (Chapin et al 1980). Contrary to studies postulating low seed viability, low germination, and high proportions of clonal reproduction, other studies report medium to high germination percentages of arctic species (Mooney and Billings 1961;Bell and Bliss 1980;Bliss and Gold 1999;Hagen 2002). Also, many arctic species have high levels of genetic diversity (reviewed by Brochmann and Brysting 2008).…”