SEED GERMINATION IN ARCTIC AND ALPINE SPECIES
A RCTIC and alpine species today occupy large areas that only a few thousand years ago were covered by great ice sheets or the sea. Not all arctic land areas were glaciated, however, for refugia such as Beringia, the coast of northern Alaska, the Yukon valley, and a part of the Arctic Archipelago re...
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| Language: | English |
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| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.552.8671 http://pubs.aina.ucalgary.ca/arctic/Arctic11-3-180.pdf |
| Summary: | A RCTIC and alpine species today occupy large areas that only a few thousand years ago were covered by great ice sheets or the sea. Not all arctic land areas were glaciated, however, for refugia such as Beringia, the coast of northern Alaska, the Yukon valley, and a part of the Arctic Archipelago remained free of ice and there many species were able to survive, rather than suffer extinction or be forced by the advancing ice to migrate south (HultCn, 1937). Although the numbers of biotypes (or strains) of many species were reduced and thus the adaptability of these species impaired by the considerable climatic changes caused by the alternation of warm and dry interglacial and cold glacial periods, many retained the capacity to recolonize their former habitats after the ice had finally retreated. This recolonization is the result of both vegetative repro-duction by bulblets, runners, rhizomes, etc., and dispersal by seeds. The present study was undertaken to give a better understanding of seed viability of both arctic and alpine species; for field observations indi-cate that seedlings are not numerous, especially in the Arctic. Nomenclature follows that of HultCn (1941-50) for the arctic species and Harrington (1954) for the alpine species. Appreciative acknowledgement is made to the De-partment of Botany, Duke University, where the germination tests were made and to Boston Physical Research Laboratories under the auspices of which the Alaskan work was carried out. An extensive study of flower development and seed germination of arctic-alpine species has been made by Soyrink1 (1938-9) in Petsamo-Lappland. Of 91 species tested 79 germinated. Sgrensen (1941) ran germi-nation tests on the seeds of 99 species in northeast Greenland, in which those of 62 species germinated. Nearly one half of those that failed to germinate belonged to the Cyperaceae (sedge family). He found that germi-nation occurred even though the seeds remained frozen for almost half of each 24-hour period. Seed production by arctic and alpine ... |
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