Biota and Ecological Communities
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Biota and Ecological Communities Chapter 3 Prepared by Brad Stelfox and Bob Wynes Contributors: Chris Buddle Doug Collister Bert Finnamore Greg Greidanus Linda Halsey James Hammond Archie Landals Dave Moyles Mike Michaelian Rick Schneider Bob Shelast Dale Vitt Cliff Wallis Dave Walty Summary Points • Northwest Alberta possesses a diverse biota, including both flora and fauna. • Although our knowledge of the diversity of more primitive simple organisms is grossly incomplete, we do know that they contain remarkable species richness, and play a critical role within ecological communities. • Systematic and comprehensive inventories exist for but a few species in northwest Alberta, and these are confined to those profile species viewed critical in terms of consumptive use or endangered status. • The biotic communities of northwest Alberta are exceptionally young from a geologic perspective, reflecting the recent retreat of regional glacial ice sheets ~10,000 years ago. • Currently, plant communities are diverse and reflect physiographic differences in elevation, slope, aspect and relief, and to a significant extent, disturbance regimes. This gradient in plant community structure has been stratified into assemblages defined as “natural subregions”. • A considerable portion of northwest Alberta is low in elevation with impaired or minimal drainage. These areas are characterized by fen and bog complexes. Although poorly understood in terms of their ecological role, these organic comlexes contain vast amounts of organic carbon and are pivotal to the hydrological cycle of the region. • In comparison to more southerly or more coastal regions of similar size in North America, northwest Alberta has a relatively depauperate fish, reptile, amphibian and mammalian fauna. It does, however, support a remarkably high species richness for birds, largely owing to the great number of neotropical bird species that migrate to northwest Alberta to breed and nest during the summer season. • Those vertebrate species considered to be in need of special management attention for purposes of conserving viable populations in the region include the trumpeter swan, woodland caribou, arctic grayling, and wood bison. • The level of protection afforded the various natural subregions from industrial activity varies considerably. Most protected areas are in the size range of 100-1000 ha, although the greatest amount of area protected comes from protected areas in the 10,000-100,000 ha range. Those natural subregions currently possessing no level of protection include the Lower Foothills, the Central Mixedwoods, and the Peace River Lowlands. Minimal level of protection exist for the Dry Mixedwood (0.7%), and the Peace River Parkland (1.3%). A moderate level of protection is offered to the Subarctic (4.7%) and Boreal Highlands (5.6%) and a high level of protection exists for the Wetland Mixedwood (12.3%). Biota and Ecological Communities 3-1 Table of Contents Summary Points.............................................................................................................................................................1 Taxonomic Summary ..................................................................................................................................................11 Plants ...........................................................................................................................................................................15 Species Richness.....................................................................................................................................................15 Development of plant communities in post-glacial northwest Alberta...................................................................36 Early Post-glacial Conditions (12,000 to 11,000 BP) ........................................................................................36 The Rise of Upland Woodlands (11,000 to 8,700 BP).......................................................................................37 The Pine Peak (8,700 to 5,000 BP) ....................................................................................................................37 A Cooler and Moister Climate – Development of Contemporary Vegetation (5,700 BP to present) ................38 The 20th Century and the Importance of Disturbance Events............................................................................38 References..........................................................................................................................................................40 Peatland Complexes ....................................................................................................................................................41 Definition Of Wetlands And Wetland Classes .......................................................................................................41 Distribution of Peatlands in northwest Alberta.......................................................................................................43 Definition and Identification of Wetland Landforms..............................................................................................45 Bogs ...................................................................................................................................................................46 Fens ....................................................................................................................................................................47 Marshes ( Mong ).................................................................................................................................................49 Swamps ..............................................................................................................................................................49 Shallow Open Waters ( Wonn )...........................................................................................................................49 References ..............................................................................................................................................................56 Arthropods...................................................................................................................................................................57 General Review of Arthropods of the Boreal Forest ..............................................................................................57 Overview: Arthropod Diversity .........................................................................................................................57 The Importance of Arthropods in Forest Ecosystems ........................................................................................57 Arthropod Sampling...........................................................................................................................................58 Case Studies of Arthropods in the Boreal Forests of Alberta.............................................................................58 Summary ............................................................................................................................................................60 Other Research Priorities ...................................................................................................................................66 References..........................................................................................................................................................68 Insects of Economic Interest to the Forest Sector...................................................................................................70 Background ........................................................................................................................................................70 Spruce Budworm................................................................................................................................................70 Forest Tent Caterpillar .......................................................................................................................................70 Aspen Tortrix .....................................................................................................................................................70 Other Species .....................................................................................................................................................70 Methodology ......................................................................................................................................................70 Control Programs ...............................................................................................................................................71 Fishes...........................................................................................................................................................................72 Species Richness.....................................................................................................................................................72 Fish Distribution and Abundance in Lakes.............................................................................................................72 Fish Distribution and Abundance in Rivers and Streams .......................................................................................72