Global Change and the Boreal Forest: Thresholds, Shifting States or Gradual Change?

Abstract Changes in boreal climate of the magnitude projected for the 21st century have always caused vegetation changes large enough to be societally important. However, the rates and patterns of vegetation change are difficult to predict. We review evidence suggesting that these vegetation changes may be gradual at the northern forest limit or where seed dispersal limits species distribution. However, forest composition may be quite resilient to climate change in the central portions of a species range until some threshold is surpassed. At this point, changes can be rapid and unexpected, often causing a switch to very different ecosystem types. Many of these triggers for change are amenable to management, suggesting that our choice of policies in the coming decades will substantially influence the ecological and societal consequences of current climatic change.

[1]  Leslie A. Viereck,et al.  Decadal observations of tree regeneration following fire in boreal forests , 2004 .

[2]  G. Kling,et al.  Holocene pollen records from the central Arctic Foothills, northern Alaska: testing the role of substrate in the response of tundra to climate change , 2003 .

[3]  G. Juday,et al.  A 200-Year Perspective of Climate Variability and the Response of White Spruce in Interior Alaska , 2003 .

[4]  H. Linderholm,et al.  Tree-ring records from central Fennoscandia: the relationship between tree growth and climate along a west–east transect , 2003 .

[5]  R. Crawford,et al.  Paludification and forest retreat in northern oceanic environments. , 2003, Annals of botany.

[6]  Y. Bergeron,et al.  Fire-induced decrease in forest cover on a small rock outcrop in the Abitibi region of Québec, Canada , 2003 .

[7]  L. F. J. O H N S T O N E,et al.  Non-equilibrium succession dynamics indicate continued northern migration of lodgepole pine , 2003 .

[8]  Vlassova Tk.  Human impacts on the tundra-taiga zone dynamics: the case of the Russian lesotundra. , 2002 .

[9]  R. Crawford,et al.  The tundra-taiga interface and its dynamics: concepts and applications. , 2002, Ambio.

[10]  Robert Baxter,et al.  How will the tundra-taiga interface respond to climate change? , 2002, Ambio.

[11]  E. Johnson,et al.  Accurately ageing trees and examining their height‐growth rates: implications for interpreting forest dynamics , 2002 .

[12]  A. Starfield,et al.  Patterns and dynamics of treeline advance on the Seward Peninsula, Alaska , 2002 .

[13]  J. Lynch,et al.  Geographic and temporal variations in fire history in boreal ecosystems of Alaska , 2002 .

[14]  Alain Leduc,et al.  Natural fire regime : a guide for sustainable management of the Canadian boreal forest , 2002 .

[15]  T. Vlassova.  Human impacts on the tundra-taiga zone dynamics: the case of the Russian lesotundra. , 2002, Ambio.

[16]  Alain Leduc,et al.  Silvicultural disturbance severity and plant communities of the southern Canadian boreal forest , 2002 .

[17]  M. Fortin,et al.  The Subarctic Forest–Tundra: The Structure of a Biome in a Changing Climate , 2001 .

[18]  B. A. Yurtsev.  The Pleistocene ``Tundra-Steppe'' and the productivity paradox: the landscape approach , 2001 .

[19]  P. Richard,et al.  Holocene changes in seasonal precipitation highlighted by fire incidence in eastern Canada , 2000 .

[20]  Bruce P. Finney,et al.  Reduced growth of Alaskan white spruce in the twentieth century from temperature-induced drought stress , 2000, Nature.

[21]  F. Chapin,et al.  Consequences of changing biodiversity , 2000, Nature.

[22]  T. Virtanen,et al.  Performance of moth larvae on birch in relation to altitude, climate, host quality and parasitoids , 1999, Oecologia.

[23]  Malcolm L. Hunter,et al.  Maintaining Biodiversity in Forest Ecosystems , 2000 .

[24]  Alain Leduc,et al.  Forest management guidelines based on natural disturbance dynamics: Stand- and forest-level considerations , 1999 .

[25]  D. Mann,et al.  Vegetation and soil development at an upland taiga site, Alaska , 1999 .

[26]  J. Ashby.  References and Notes , 1999 .

[27]  P. Angelstam.  Maintaining and restoring biodiversity in European boreal forests by developing natural disturbance regimes , 1998 .

[28]  L. Sirois,et al.  Vegetation changes caused by recent fires in the northern boreal forest of eastern Canada , 1998 .

[29]  E. Johnson,et al.  Wildfires in the western Canadian boreal forest: Landscape patterns and ecosystem management , 1998 .

[30]  O. Tenow.  Hazards to a mountain birch forest-Abisko in perspective. , 1996 .

[31]  I. Snowball,et al.  Holocene forest dynamics and climate changes in the Abisko area, northern Sweden - the Sonesson model of vegetation history reconsidered and confirmed , 1996 .

[32]  James S. Clark,et al.  Terrestrial biotic responses to environmental change and feedbacks to climate , 1996 .

[33]  James F. Reynolds,et al.  Steppe-Tundra Transition: A Herbivore-Driven Biome Shift at the End of the Pleistocene , 1995, The American Naturalist.

[34]  C. T. Dyrness,et al.  An overview of the vegetation and soils of the floodplain ecosystems of the Tanana River, interior Alaska , 1993 .

[35]  P. Bartlein,et al.  Global Changes During the Last 3 Million Years: Climatic Controls and Biotic Responses , 1992 .

[36]  Leslie A. Viereck,et al.  ELEMENT CYCLING IN TAIGA FORESTS : STATE-FACTOR CONTROL , 1991 .

[37]  A. Lister.  Frozen fauna of the mammoth steppe: the story of blue babe , 1991 .

[38]  R. Owen-Smith,et al.  Megaherbivores: The Influence of Very Large Body Size on Ecology , 1990 .

[39]  J. Denslow.  Seed Ecology , 1986 .

[40]  F. S. Chapin,et al.  Browsing-Woody Plant Interactions During Boreal Forest Plant Succession , 1986 .

[41]  Leslie A. Viereck,et al.  Vegetation, soils, and forest productivity in selected forest types in interior Alaska , 1983 .

[42]  M. B. Davis,et al.  Quaternary history and the stability of forest communities , 1981 .

[43]  M. Sonesson.  Late Quaternary Forest Development of the Torneträsk Area, North Sweden. 2. Pollen Analytical Evidence@@@Late Quaternary Forest Development of the Tornetrask Area, North Sweden. 2. Pollen Analytical Evidence , 1974 .

[44]  M. Sonesson,et al.  Late Quaternary Forest Development of the Torneträsk Area, North Sweden. 1. Structure of Modern Forest Ecosystems@@@Late Quaternary Forest Development of the Tornetrask Area, North Sweden. 1. Structure of Modern Forest Ecosystems , 1974 .

[45]  M. Sonesson.  Pollen zones at Abisko, Torne lappmark, Sweden. , 1968 .

[46]  R. Whittaker,et al.  GRADIENT ANALYSIS OF VEGETATION* , 1967, Biological reviews of the Cambridge Philosophical Society.