COMMUNITY CHANGE (SUCCESSION) Krebs cpt. 21; pages 403-424; 431.
COMMUNITY CHANGE (SUCCESSION)
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COMMUNITY CHANGE COMMUNITY CHANGE (SUCCESSION) (SUCCESSION) Krebs chap. 21; pages Krebs chap. 21; pages 403-424; 431 403-424; 431 “the non-seasonal, directional and continuous pattern of colonization and extinction of species populations on a site”
description
COMMUNITY CHANGE (SUCCESSION). “the non-seasonal, directional and continuous pattern of colonization and extinction of species populations on a site”. Krebs chap. 21; pages 403-424; 431. PRIMARY SUCCESSION. Mt. St. Helens pp403-405. Lake Michigan dunes pp416-419. Glacier Bay pp413-416. - PowerPoint PPT Presentation
Transcript of COMMUNITY CHANGE (SUCCESSION)
COMMUNITY CHANGE COMMUNITY CHANGE (SUCCESSION)(SUCCESSION)
Krebs chap. 21; pages 403-424; 431Krebs chap. 21; pages 403-424; 431
“the non-seasonal, directional and continuous pattern of colonization and extinction of species populations on a site”
PRIMARY SUCCESSION
Mt. St. Helens pp403-405
Lake Michigan dunes pp416-419
Glacier Bay pp413-416
SECONDARY SUCCESSION
Krebs pp419-422
Abandoned fields
Forest regrowth
Abandoned lots
Mount St. Helens
Vegetation recovery
Sand dune ecology
Vegetationhummock
Beachgrass
Fig 21.11 Profile of Lake Michigan sand dunes
succession
“SFT” – space-for-time substitution
pastpresent
“Polyclimax” sand dune successions Fig. 21-12
Krebs Fig. 21.7
Ice recession in Glacier Bay, Alaska, since 1760
1940
1860
1760
Alders and cottonwoods covering the hillsides
50 years
Spruce coming into the alder and cottonwood forest
100 years
Spruce and hemlock forest
250 years
Fig 21.9 Change in soil-N
Topsoil
Mineral
soil
1 year later
Wildfire
Wind disturbance (“blowdowns”)
Opax Mountain Silvicultural Systems Trial
(near Kamloops, BC)
Control burning
Control burning
Control burn plot
Monitoring succession after fire
