Page 685 - Geosystems An Introduction to Physical Geography 4th Canadian Edition

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PACIFIC OCEAN
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ATLANTI C OCEAN
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ARABIAN SEA
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INDIAN
Tropic of Capricorn
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BAY OF BENGAL
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OCEAN
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Equator
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REGIONS:
Taiga plains Boreal plains Boreal shield Boreal cordillera Pacific maritime Montane cordillera Prairies
Atlantic maritime (b) Mixedwood plains
FOREST TYPES:
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ARTIC OCEAN
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Arctic Circle
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CANADA
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MODIFIED GOODE’S HOMOLOSINE EQUAL-AREA PROJECTION
100 to 250 years to reestablish after a major disturbance. Once cleared and abandoned, the former forest becomes a mass of low bushes intertwined with vines and ferns, slowing the return of trees.
Satellite images show rainforest destruction over the past several decades. For example, new roads and for- est removal have significantly changed the landscape of the state of Rondônia in western Brazil (Figure GIA 20.2; note the encroachment along new roads branching from highway BR364). The edges of every road and cleared area represent a significant portion of the habitat disturbance— more impact occurs along these edges than in the tracts of clear-cut logging and burning. The hotter, drier, and wind- ier edge conditions penetrate the forest up to 100 m and affect species and community dynamics.
In Brazil, deforestation has decreased in recent years as the government has stepped up enforcement to preserve the forest; 2009–2010 combined losses were
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Coniferous forest Broadleaf forest
Mixed forest Transitional forest Tundra and permafrost
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Chapter 20 Terrestrial Biomes 649
PACIFIC
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Tropic of Cancer
CORAL SEA
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