Arctic plant ecology: From tundra to polar desert in Svalbard - Unis

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al. (2007) found that at low temperatures (−2.1 °C annual mean), biodiversity was negatively correlated with net primary production. In Svalbard the annual mean temperature range from 7°C to 15°C, so our study does not confirm this view. In a fertilization experiment in borealalpine Alaska, Fox (1992) found a change in growth form and species composition rather than effects on species richness. It is possible that community productivity, as well as other abiotic variables, may have a larger influence on species composition, rather than direct effects on species richness. Although our different measures of biodiversity is not clearly concordant, the observed pattern was that the dominant species, mainly woody perennials and dwarf shrubs, were the first to disappear in the areas with harsher environmental conditions (zone B and A), whereas a fairly large number of species persist, but with very few individuals. Our prediction concerning pH and species richness was not supported by our data, although the relationship between pH and species richness has been positively correlated in numerous studies from different vegetation types, such as arctic tundra (Gough et al. 2000, Gould & Walker 1999), temperate heath and grassland (Roem & Berendse 2000) as well as Svalbard (Wenche et al. 2002). Our sample sites were, however, distributed within a relatively narrow range of pH (5.58.5), thus the full effect of pH on species richness could not be studied. The prediction on soil moisture was not supported in our study. Explanations for this could be that it was measured on a coarse scale, wherein most estimations of moisture turned out to be medium. In addition these measures also were heavily influenced by precipitation in the preceding 24 hours. Our ordination tests (PCA and RDA) gave no significant results, but indicated which factors are most important in explaining species richness. Bioclimatic zone and organic soil depth explain the increased species diversity. Bare ground cover is negatively correlated to all of our diversity measures. This is also in line with the results of our ANOVA. As to why we could not get a significant explanation, we suggest that different factors may be acting with different strength in different zones. Conclusion Differences in biodiversity are found when looking at a landscape level and not at plot (α) level, among frames at different sites. Hence, what creates high biodiversity in the Arctic seems to be variation of habitats and vegetation types on the landscape. We welcome further studies on this explanation model, and conclude that if supported by more general data, this may be an important finding concerning vulnerable Arctic ecosystems. If landscape heterogeneity is the major source of Arctic biodiversity, policymakers need to take this into consideration for future conservation of the Arctic environment Acknowledgements We thank Inger Greve Alsos and David F. Murray for advices and comments through all the process, and the participants in the course AB326 Arctic Plant Ecology 2007 for fruitful discussions. References Abdi, H. 2007: The Bonferonni and Šidák corrections for multiple comparisons. In: Salkind, N. (Ed), Encyclopedia of Measurement and Statistics. Sage, Thousand Oaks 20
Barrett, P.E. & Teeri, J.A. 1973: Vascular plants of the Truelove Inlet region, Devon Island. Arctic 26: 5867 Bay, C. 1992: A phytogeographical study of the vascular plants of northern Greenland north of 74 degrees northern latitude. Meddelelser om Grønland Bioscience 36 Beschel, R.E. 1963: Geobotanical studies on Axel Heiberg Island in 1962. Pp. 118 in: Müller, F. (Ed), Axel Heiberg Preliminary Rept. 19611962. McGill University Billings, W.D. 1992: Phytogeographic and evolutionary potential of the arctic flora in a changing climate. Pp: 5989 in: Chapin FS III, Jefferies RL, Reynolds, JF, Shaver GS, Svoboda J (Eds) Arctic ecosystems in a changing climate: an ecophysiological perspective. Academic Press, San Diego Bird, C.D. 1975: The lichen, bryophyte, and vascular plant flora and vegetation of the Landing Lake area, Prince Patrick Island, arctic Canada. Canadian Journal of Botany 53: 719744 Brassard, G. & Beschel, R.E. 1968: The vascular flora of Tanquary Fiord, northern Ellesmere Island, N.W.T. Canadian FieldNaturalist 82: 103113 Brassard, G. & Langton, R.E. 1970: The flora and vegetation of Van Hauen Pass, northwestern Ellesmere Island. Canadian FieldNaturalist 84: 357364 Bruggermann, P.F. & Calder, J.A. 1953: Botanical investigation in northeast Ellesmere Island, 1951. Canadian FieldNaturalist 67: 157174 Bråthen, K.A. & Hagberg, O. 2004: more efficient estimation of plant biomass.Journal of Vegetation Science 15:653660 CAVM(Circumpolar Arctic Vegetation Map) Team. 2003: Circumpolar Arctic Vegetation Map. Scale 1:7 500 000. Conservation of Arctic Flora and Fauna (CAFF) Map no. 1 U.S. Fish and Wildlife service, Anchorage, Alaska Conover, W.J. 1998: Practical nonparametric statistics. John Wiley and Sons, New York Costanza, R., Fisher, B., Mulder, K., Liu, S. & Christopher, T. 2007: Biodiversity and ecosystem services: A multiscale empirical study of the relationship between species richness and net primary production. Ecological Economics 61: 478491 Crawley, M. J. 2002: Staistical computing: an introduction to data analysis using S plus. John Wiley and Sons Ltd., Chichester Elvebakk, A. 2005: A vegetation map of Svalbard on the scale 1:3.5 mill. Phytocoenologia 35: 951967 Elvebakk, A., Elven, R. & Razzhivin, V.Y. 1999: Delimitation, zonal and sectorial subdivision of the Arctic for the Panarctic Flora Project. Det Norske Vitenskaps Akademi. I. Matematisk Naturvitenskapelig Klasse. Skrifter. Ny serie 38: 375386 Elven, R., Murrey, D.F., Razzhivin, V. & Yurtsev, B.A. 2007: Checklist for the Panarctic Flora (PAF): Vascular Plants. Draft Version. University of Oslo, Oslo Fox, J.F. 1992: Responses of diversity and growth form dominance to fertility in Alaskan tundra fellfield communities. Arctic and Alpine research 24:233237 21
Page 1 and 2: Arctic plant ecology: From tundra t
Page 3 and 4: Arctic plant ecology: From tundra t
Page 5 and 6: localities in western and northern
Page 7 and 8: seamed to decrease from zone C to A
Page 9: Raup, H. M. 1965: The flowering pla
Page 12 and 13: them supporting his theory (e.g., H
Page 14 and 15: Site ID Table 1. Sites analysed in
Page 16 and 17: Table 2. Kendall’s τ correlation
Page 18 and 19: The RDA ordination (Fig. 4) showed
Page 22 and 23: Franzèn, D. & Molau, U. 1999: Vasc
Page 24 and 25: Tilman, D. 1982: Resource Competiti
Page 26 and 27: Juncus biglumis L. Luzula confusa L
Page 28 and 29: Puccinellia phryganodes (Trin.) Scr
Page 30 and 31: #Saxifraga nivalis L. *Saxifraga op
Page 32 and 33: *Coptidium lapponicum (L.) Tzvelev
Page 34 and 35: esponse curve. With rising temperat
Page 36 and 37: N Biscayarhuken Florabukta Reinsdyr
Page 38 and 39: of cold summers can be terminal for
Page 40 and 41: Results Ecological amplitudes of va
Page 42 and 43: A potential substrate area could be
Page 44 and 45: no. of districts 30 25 20 15 10 5 0
Page 46 and 47: tetragona, Erigeron humilis, Minuar
Page 48 and 49: with the species occurring on Svalb
Page 50 and 51: and substrate map show a clear occu
Page 52 and 53: Alsos, I. G. 2007: Frequent LongD
Page 54 and 55: Walker, M., Wahren, C., Hollister,
Page 56 and 57: northern hemisphere (Brochmann et a
Page 58 and 59: an enclave of bioclimatic zone C wi
Page 60 and 61: Table 3. Formulas of the different
Page 62 and 63: Figure 2. a: Cumulative number of s
Page 64 and 65: Figure 4. Presence and absence of a
Page 66 and 67: (2003), from which a highly signifi
Page 68 and 69: The intermediate stages seem to hav
Page 70 and 71:
Svalbard in general. Moreover polyp
Page 72 and 73:
Svoboda, J., Henry, G. H. R. 1987:
Page 74 and 75:
limited by nutrient availability ra
Page 76 and 77:
flower. Care was taken to measure o
Page 78 and 79:
Biomass Biomass per unit land area
Page 80 and 81:
Luzula nivalis Juncus biglumis Drya
Page 82 and 83:
References Arft, A. M., Walker, M.
Page 84 and 85:
partly lose their high altitude/lat
Page 86 and 87:
preferably grow in rosettes, which
Page 88 and 89:
Forbs Graminoid Graminoids In grami
Page 90 and 91:
latitude plants on Svalbard to keep
Page 92 and 93:
Elvebakk A. 1999: Bioclimatic delim
Page 94 and 95:
a climate description see Rønning
Page 96 and 97:
Results and Discussion The minimum
Page 98 and 99:
Table 2. Ranking of examined plant
Page 100:
References Biebl, R. 1968: Über W
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Arctic plant ecology: From tundra to polar desert in Svalbard - Unis

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