British Columbia Vegetation and Climate History with Focus on 6 ka BP
Richard J. Hebda
ABSTRACT
British Columbia Holocene vegetation and climate is reconstructed from pollen records. A coastal Pinus contorta paleobiome developed after glacier retreat under cool and probably dry climate. Cool moist forests involving Picea, Abies, Tsuga spp., and Pinus followed until the early Holocene. Pseudotsuga menziesii arrived and spread in the south 10 000-9000 BP, and Picea sitchensis - Tsuga heterophylla forests developed in the north. T. heterophylla increased 7500-7000 BP, and Cupressaceae expanded 5000-4000 BP. Bogs began to develop and expland. Modern vegetation arose 4000-2000 BP. There were early Holocene grass and Artemisia communities at mid-elevations and pine stands at high elevations in southern interior B.C. Forests expanded downslope and lakes formed 8500-7000 BP. Modern forests arose 4500-4000 BP while lower and upper tree lines declined. In northern B.C. non-arboreal communities preceded middle Holocene Picea forests. Abies, Pinus and Picea mariana predominated at various sites after 4000 BP. At 6000 BP Tsuga heterophylla (south) and Picea sitchensis (north) dominated the coast and islands and Quercus garryana and Pseudotsuga on southeast Vancouver Island, but Thuja plicata was infrequent. Southern Interior Plateau vegetation at 6000 BP was more open than today at middle to lower elevations, whereas forests covered the Northern Interior Plateau. Picea forests occurred in northern B.C. Holocene climate phases were: 1) warm dry "xerothermic" ca. 9500-7000 BP, 2) warm moist "mesothermic" ca. 7000-4500 BP, 3) moderate and moist 4500-0 BP, with increasing moisture 8500-6000 BP and cooling (?increased moisture) 4500-3000 BP. B.Cs Hypsithermal had dry and wet stages; 6000 BP occurred in the warm and wet mesothermic stage.
RÉSUMÉ
Histoire du climat et de la végétation de la Colombie-Britannique, notamment de la période de 6 ka BP
Cette reconstitution a été effectuée à partir des données polliniques. Un paléobiome à Pinus contorta s'est établi après le retrait des glaciers sous un climat frais et probablement sec. Des forêts de climat frais et humide à dominance de Picea, Abies, Tsuga spp. et Pinus ont suivi, jusqu'à l'Holocène inférieur. Pseudotsuga menziesii s'est ensuite répandu dans le sud de 10 000 à 9000 BP, tandis que les forêts à Picea sitchensis - Tsuga heterophylla se sont répandues dans le nord. T. heterophylla s'est accru de 7500 à 7000 BP et Cupressaceae s'est répandu de 5000 à 4000 BP. La végétation moderne s'est manifestée de 4000-2000 BP. Dans le sud de la partie intérieure, il y a eu des herbes et des communautés d'Artemisia aux altitudes moyennes et des peuplements de pins en haute altitude au début de l'Holocène. Les forêts modernes se sont formées de 4500 à 4000 BP, tandis que les limites des arbres déclinaient. Au nord, les communautés non arboréennes ont précédé les forêts de pins de l'Holocène moyen. Abies, Pinus et Picea mariana ont prédominé en différents sites après 4000 BP. À 6000 BP, Tsuga heterophylla (au sud) et Pinus sitchensis (au nord) ont dominé sur les côtes et les îles et Quercus garryana ainsi que Pseudotsuga, le sud-est de l'île de Vancouver. La végétation du sud du plateau intérieur à 6000 BP était plus ouverte que maintenant aux altitudes moyennes et basses, tandis que les forêts couvraient le nord du plateau intérieur. Les forêts de Picea occupaient le nord de la Colombie-Britannique. Les phases climatiques à l'Holocène sont les suivantes : 1) une phase chaude et sèche, dite xérothermique, vers 9500-7000 BP, 2) une phase chaude et humide dite mésothermique, vers 7000-4500 BP, 3) une phase tempérée et humide de 4500 à 0 BP, avec une humidité croissante de 8500 à 6000 BP et un refroidissement (et humidité croissante ?) de 4500-3000 BP. À l'hypsithermal, le climat était tantôt sec, tantôt humide.
ZUSAMMENFASSUNG
Geschichte der Vegetation und des Klimas in British Columbia während des Holozäns, besonders um 6 ka v.u.Z.
Ein Kùsten-Palâobiom mit Pinus contorta entwickelte sich nach dem Rùckzug des Gletschers wàhrend eines kalten und wohl trockenen Klimas. Darauf folgten kalte feuchte Wàlder mit Picea, Abies, Tsuga spp. und Pinus bis zum frùhen Holozân. Pseudotsuga menziesii breitete sich dann in Sùden von 10 000 bis 9000 v.u.Z. aus, und Picea sitchensis - Tsuga-Wàlder entwickelten sich im Norden. T. heterophylla nahm von 7500-7000 v.u.Z. zu, und Cupressaceae etablierte sich von 5000-4000 v.u.Z. Sùmpfe begannen zu entstehen und sich auszubreiten. Es gab im frùhen Holozân Gras- und Artemisia-Einheiten in mittleren Hôhen und Kiefer-Populationen in groBen Hôhen im sùdlichen lnnern von British Columbia. Moderne Wàlder entstanden zwischen 4500-4000 v.u.Z. wàhrend die untere und obère Baumgrenze zurùckgingen. In Nord-B.C gab es nichtbaumartige Einheinten vor den P/cea-Wâldem des mittleren Holozân. An verschiedenen Plàtzen dominierten Abies, Pinus und Picea mariana nach 4000 v.u.Z. Um 6000 v.u.Z. dominierten an der Kùste und auf den Insein Tsuga heterophylla (im Sùden) und Picea sitchensis (im Norden) und Quercus garryana und Pseudotsuga im Sùdosten der Insel Vancouver, aber Thuja plicata war selten. Die Vegetation im Sùden des inneren Plateaus um 6000 v.u.Z. war offener als heute in mittleren und niedrigen Hôhen, wàhrend Wàlder das nôrdliche innere Plateau bedeckten. P/cea-Wàlder gab es in Nord-B.C. Die Klimaphasen im Holozân waren: 1) eine warme trockene "xerothermische", Phase etwa 9500-7000 v.u.Z., 2) eine warme feuchte "meso-thermische" Phase etwa 7000-4500 v.u.Z., eine gemàBigte und feuchte Phase 4500-0 v.u.Z., mit zunehmender Feuchtigkeit von 8500-6000 v.u.Z. und Abkùhlung (und zunehmender Feuchtigkeit?) 4500-3000 v.u.Z.
Bibliography
Allen, G.B., 1995. Vegetation and climate history from the CDF and CDF/ CWH transition on south east Vancouver Island. M.Sc. thesis. School of Earth and Ocean Sciences, University of Victoria.
Allen, G.B. and Hebda, R.J., 1993. Forest history of south Vancouver Island British Columbia, since déglaciation. Abstract in Program with Abstracts and Field Guide. Canadian Quaternary Association Meeting, April 18-21, 1993, Victoria, B.C., p. A1.
Alley, N.F., 1976. The palynology and palaeoclimatic significance of a dated core of Holocene peat, Okanagan Valley, southern British Columbia. Canadian Journal of Earth Sciences, 13: 1131-1144. DOI:10.1139/e76-115
Anderson, R.Y., Nuhfer, E.B. and Dean, W.E., 1984. Sinking volcanic ash in uncompacted sediment in Williams Lake, Washington. Science, 225: 505-508. DOI:10.1126/science.225.4661.505
Bacon, CR., 1983. Eruptive history of Mount Mazama and Crater Lake Caldera, Cascade Range, U.S.A. Journal of Volcanology and Geothermal Research, 18: 57-115. DOI:10.1016/0377-0273(83)90004-5
Banner, A., Pojar, J. and Rouse, G.E., 1983. Postglacial paleoecology and successional relationships of bog woodland near Prince Rupert, British Columbia. Canadian Journal of Forest Research, 13: 938-947. DOI:10.1139/x83-125
Barnosky, C.W., Anderson, P.M. and Bartlein, PJ., 1987. The northwestern U.S. during déglaciation: Vegetational history and paleoclimatic implications. In W.F. Ruddiman and H.E. Wright, Jr., eds., North America and adjacent oceans during the last déglaciation. Boulder, Colorado, Geological Society of America, The Geology of North America, v. K-3.
Brown, T.A, Nelson, D.E., Mathewes, R.W., Vogel, J.S. and Southon, J.R., 1989. Radiocarbon dating of pollen by Accelerator Mass Spectrometry. Quaternary Research, 32: 205-212. DOI:10.1016/0033-5894(89)90076-8
Cawker, K.B., 1983. Fire history and grassland vegetation change: Three pollen diagrams from southern British Columbia. Canadian Journal of Botany, 61: 1126-1139. DOI:10.1139/b83-120
Clague, J.J., 1975. Late Quaternary geomorphology of the southern Rocky Mountain Trench, British Columbia. Canadian Journal of Earth Sciences, 12: 595-605. DOI:10.1139/e75-054
Clague, J.J., 1981. Late Quaternary geology and geochronology of British Columbia: Part 2: Summary and discussion of radiocarbon-dated Quaternary history. Geological Survey of Canada Paper, 80-35: 1-41.
Clague, J.J. and R.W. Mathewes, 1989. Early Holocene thermal maximum in western North America: New evidence from Castle Peak, British Columbia. Geology, 17: 277-280. DOI:10.1130/0091-7613(1989)017<0277:EHTMIW>2.3.CO;2
Cwynar, L.C., 1988. Late Quaternary vegetation history of Kettlehole Pond, southwestern Yukon. Canadian Journal of Forest Research, 18: 1270-1279. DOI:10.1139/x88-196
Deevey, E.S. and Flint, R.F., 1957. Postglacial hypsithermai interval. Science, 125: 182-184. DOI:10.1126/science.125.3240.182
Ecoregions Working Group, 1989. Ecoclimatic Regions of Canada, First Approximation. Ecoregions Working Group of the Canada Committee on Ecological Land Classification. Ecological Land Classification Series, No. 23, Sustainable Development Branch, Canadian Wildlife Service, Conservation and Protection, Environment Canada, Ottawa, 119 p.
Fedje, D.W., 1993. Sea-levels and prehistory in Gwaii Haanas. M.A. thesis, Department of Archaeology, University of Calgary.
Feng, X. and Epstein, S., 1994. Climatic implications of an 8000-year Hydrogen isotope time series from Bristlecone Pine trees. Science, 265: 1079-1081. DOI:10.1126/science.265.5175.1079
Fergusson, A. and Hills, L.V., 1985. A palynological record, Upper Elk Valley, British Columbia, p. 370-396. In CR. Harington, éd., Climatic Change in Canada 5: Critical Periods in the Quaternary Climatic History of Northern North America. Syllogeus 55.
Fulton, R., 1971. Radiocarbon geochronology of southern British Columbia. Geological Survey of Canada, Paper 71-37: 1-28.
Gottesfeld, A.S., Mathewes, R.W. and Gottesfeld, L.M.J., 1991. Holocene debris flows and environmental history, Hazelton area, British Columbia. Canadian Journal of Earth Sciences, 28: 1583-1593. DOI:10.1139/e91-142
Hansen, H.P., 1947, Postglacial forest succession, climate and chronology, in the Pacific Northwest. Transactions of the American Philosophical Society (N.S.) 37(1).
Hazell, S., 1979. Late Quaternary vegetation and climate of Dunbar Valley, British Columbia. M.Sc. thesis. Department of Botany, University of Toronto, 101 p.
Hebda, R.J., 1977. The paleoecology of a raised bog and associated deltaic sediments of the Fraser River Delta. Ph.D. thesis. University of British Columbia, Vancouver, 201 p.
Hebda, R.J., 1982a. A 13,000 year record of vegetation, Hat Creek Valley, southcentral British Columbia. Abstracts, American Quaternary Association Seventh Biennial Conference, Seattle, Washington, p. 99.
Hebda, R.J., 1982b. Postglacial history of grasslands of southern British Columbia and adjacent regions, p. 157-191. In A.C. Nicholson, A. McLean, and T.E. Baker, eds., Grassland Ecology and Classification Symposium Proceedings. British Columbia Ministry of Forests, Victoria.
Hebda, R.J., 1983. Late-glacial and postglacial vegetation history at Bear Cove Bog, northeast Vancouver Island, British Columbia. Canadian Journal of Botany, 61:3172-3192. DOI:10.1139/b83-355
Hebda, R.J., 1984. Postglacial vegetation history of Brooks Peninsula, Vancouver Island, British Columbia. Abstracts. 6th International Palynological Conference, August 26 - September 1, 1984, Calgary, Canada, p. 62.
Hebda, R.J., 1993. Climate history, Heal Lake, Vancouver Island, British Columbia. Program with Abstracts and Field Guide. Canadian Quaternary Association Meeting, April 18-21, 1993, Victoria, B.C. p A20.
Hebda, R.J., (in press). Late Quaternary Paleoecology of Brooks Peninsula. In R.J. Hebda and J.C Haggarty, eds., Brooks Peninsula: A Glacial Refugium. Royal British Columbia Museum.
Hebda, R.J. and Allen, G.B., 1993. Modern pollen spectra from west central British Columbia. Canadian Journal of Botany, 71: 1486-1495. DOI:10.1139/b93-180
Hebda, R.J. and Mathewes, R.W., 1984. Holocene history of cedar and Native Indian cultures of the North American Pacific Coast. Science. 225: 711-713. DOI:10.1126/science.225.4663.711
Heusser, C.J., 1960. Late-Pleistocene environments of North Pacific North America. American Geographical Society Special Publication No. 35.
Heusser, C.J., 1985. Quaternary pollen records from the Interior Pacific Northwest Coast: Aleutians to the Oregon-California boundary, p. 141-165. In V.M. Bryant and R.G. Holloway, eds., Pollen Records of Late-Quaternary North American Sediments. American Association of Stratigraphie Palynologists Foundation, Dallas.
Heusser, C.J., Heusser, L.E. and Peteet, D.M., 1985. Late-Quaternary climatic change on the American North Pacific Coast. Nature, 315: 485-487. DOI:10.1038/315485a0
Heusser, L.E., 1983. Palynology and paleoecology of postglacial sediments in an anoxic basin, Saanich Inlet British Columbia. Canadian Journal of Earth Sciences, 20: 873-885. DOI:10.1139/e83-077
Kearney, M.S. and Luckman, B.H., 1983. Postglacial vegetation history of Tonquin Pass, British Columbia. Canadian Journal of Earth Sciences, 20: 776-786. DOI:10.1139/e83-069
Krajina, V.J., Klinka, K. and Worrall, J., 1982. Distribution and characteristics of trees and shrubs of British Columbia. Faculty of Forestry, University of British Columbia, Vancouver, 131 p.
Luckman, B.H. and Kearney, M.S., 1986. Reconstruction of Holocene changes in alpine vegetation and climate in the Maligne Range, Jasper National Park, Alberta. Quaternary Research, 26: 244-261. DOI:10.1016/0033-5894(86)90108-0
MacDonald, G.M., 1984. Postglacial plant migration and vegetation development in the western Canadian boreal forest. Ph.D. thesis, University of Toronto.
MacDonald, G.M., 1987. Postglacial development of the subalpine-boreal transition forest of western Canada. Journal of Ecology, 75: 303-320. DOI:10.2307/2260420
Mathewes, R.W., 1973. A palynological study of postglacial vegetation changes in the University Research Forest, southwestern British Columbia. Canadian Journal of Botany, 51: 2085-2103. DOI:10.1139/b73-271
Mathewes, R.W., 1985. Paleobotanical evidence for climatic change in southern British Columbia during Late-glacial and Holocene time, p. 397-422. In CR. Harington, éd., Climate Change in Canada 5: Critical Periods in the Quaternary Climatic History of Northwestern North America. Syllogeus 55.
Mathewes, R.W., 1989. Paleobotany of the Queen Charlotte Islands, p, 75-90. In G.G.E. Scudder and N. Gessler, eds., The Outer Shores. Based on the Proceedings of the Queen Charlotte Islands First International Symposium, University of British Columbia, August 1984, 327 p.
Mathewes, R.W., 1993. Evidence for Younger Dryas-Age cooling on the North Pacific Coast of America. Quaternary Science Reviews, 12: 321-331. DOI:10.1016/0277-3791(93)90040-S
Mathewes, R.W. and Heusser, L.E., 1981. A 12,000-year palynological record of temperature and precipitation trends in southwestern British Columbia. Canadian Journal of Botany, 51: 707-710. DOI:10.1139/b81-100
Mathewes, R.W. and King, M., 1989. Holocene vegetation, climate, and lake-level changes in the Interior Douglas-fir Biogeoclimatic Zone, British Columbia. Canadian Journal of Earth Sciences, 26: 1811-1825. DOI:10.1139/e89-154
Mathewes, R.W. and Rouse, GE., 1975. Palynology and paleoecology of early postglacial sediments from the lower Fraser River Canyon of British Columbia. Canadian Journal of Earth Sciences, 12: 745-756. DOI:10.1139/e75-065
Meidinger, D. and Pojar, J. (eds,), 1991. Ecosystems of British Columbia. Research Branch, Ministry of Forests, British Columbia, Victoria.
Mehringer, PJ., Jr., 1985. Late-Quaternary pollen records from the interior Pacific Northwest and northern Great Basin of the United States, p. 167-189. In V.M. Bryant and R.G. Holloway, eds., Pollen Records of Late-Quaternary North American Sediments. American Association of Stratigraphie Palynologists Foundation, Dallas.
Miller, MM. and Anderson, J.H., 1974. Out-of-phase Holocene climatic trends in the maritime and continental sectors of the Alaska-Canada Boundary Range, p. 33-58. InW.C. Mahaney, éd., Quaternary Environments: Proceedings of symposium. York University, Geographical Monographs No. 5.
Pojar, J. and Meidinger, D., 1991. British Columbia: The environmental setting, p. 39-67. In D. Meidinger and J. Pojar, eds., Ecosystems of British Columbia. Research Branch, Ministry of Forests, British Columbia. Victoria.
Pojar, J., Meidinger, D. and Klinka, K., 1991. Concepts, p. 9-37. In D. Meidinger and J. Pojar, eds., Ecosystems of British Columbia. Research Branch, Ministry of Forests, British Columbia, Victoria.
Quickfall, G.S., 1987. Paludification and the climate on the Queen Charlotte Islands during the past 8000 years. M.Sc. thesis, Department of Biological Sciences, Simon Fraser University, Burnaby, 99 p.
Reasoner, MA. and Hickman, M., 1989. Late Quaternary environmental change in the Lake O'Hara Region, Yoho National Park, British Columbia. Palaeogeography, Palaeoclimatology, Palaeoecology, 72: 291-316. DOI:10.1016/0031-0182(89)90149-1
Research Branch, 1988. Biogeoclimatic zones of British Columbia, 1988. Map 1:2,000,000. Ministry of Forests, British Columbia, Victoria.
Rowe, J.S., 1972. Forest Regions of Canada. Canadian Forestry Service, Department of the Environment, Ottawa, Publication No. 1300.
Ryder, J.M., 1987. Neoglacial history of the Stikine-Iskut area, northern Coast Mountains, British Columbia. Canadian Journal of Earth Sciences, 24: 1294-1301. DOI:10.1139/e87-125
Ryder, J.M., 1989. Holocene glacier fluctuations (Canadian Cordillera) Chapter 1. In R.J. Fulton éd., Quaternary Geology of Canada and Greenland. Geological Survey of Canada, Ottawa, Geology of Canada No. 1.
Ryder, J.M. and Thomson, B., 1986. Neoglaciation in the southern Coast Mountains of British Columbia prior to the late Neoglacial maximum. Canadian Journal of Earth Sciences, 23: 273-287. DOI:10.1139/e86-031
Spooner, I.S., 1994. Quaternary environmental change in the Stikine Plateau Region, northwestern British Columbia, Canada. Ph.D. thesis, Department of Geology and Geophysics, University of Calgary.
Stein, W.I., 1990. Quercus garryana Dougl. ex Hook Oregon White Oak, p. 650-660. In RM. Burns, and B.H. Honkala, eds., Silvics of North America Volume 2, Hardwoods. Agriculture Handbook 654, Forest Service, United States Department of Agriculture, Washington D.C.
Tsukada, M., 1982. Pseudotsuga menziesii (Mirb.) Franco: Its pollen dispersal and late Quaternary history in the Pacific Northwest. Japanese Journal of Ecology, 32: 159-181.
Wainman, N. and Mathewes, R.W., 1987. Forest history of the last 12,000 years based on plant macrofossil analysis of sediment from Marion Lake, southwestern British Columbia. Canadian Journal of Botany, 65: 2179-2187. DOI:10.1139/b87-300
Walker, LR., 1988. Late-Quaternary palaeoecology of Chironomidae (Diptera: lnsecta) from lake sediments of British Columbia. Ph.D. thesis. Department of Biological Sciences, Simon Fraser University, Burnaby. 204 p.
Walker, L.R. and Mathewes, R.W., 1989. Early postglacial chironomid succession in southwestern British Columbia, Canada, and its paleoenvironmental significance. Journal of Paleolimnology, 2: 1-14. DOI:10.1007/BF00156979
Warner, B.G., 1984. Late Quaternary paleoecology of eastern Graham Island, Queen Charlotte Islands, British Columbia, Canada. Ph.D. thesis. Department of Biological Sciences, Simon Fraser University, Burnaby, 190 p.
White, J.M. and Mathewes, R.W., 1982. Holocene vegetation and climatic change in the Peace River district, Canada. Canadian Journal of Earth Sciences, 19: 555-570. DOI:10.1139/e82-045
Williams, H.F.L. and Hebda, R.J., 1991. Palynology of Holocene top-set aggradational sediments of the Fraser River Delta, British Columbia. Palaeogeography, Palaeoclimatology, Palaeoecology, 86: 297-311. DOI:10.1016/0031-0182(91)90087-8
| Author: | Richard J. Hebda |
|---|---|
| Title: | British Columbia Vegetation and Climate History with Focus on 6 ka BP |
| Journal: | Géographie physique et Quaternaire, Volume 49, Number 1, 1995, p. 55-79 |
| URI: | http://id.erudit.org/iderudit/033030ar |
| DOI: | 10.7202/033030ar |
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