1 / 13

Altitudinal Gradients

Altitudinal Gradients. An increase in altitude (elevation) mimics a progression towards northern biomes. Altitudinal gradient on a tropical mountain. In Western Maine and New Hampshire….

bob
Télécharger la présentation

Altitudinal Gradients

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Altitudinal Gradients • An increase in altitude (elevation) mimics a progression towards northern biomes

  2. Altitudinal gradient on a tropical mountain

  3. In Western Maine and New Hampshire… • At the mountain base, northern hardwood species (sugar maple, American beech, yellow birch) or oak hardwood species • Spruce and balsam fir forests further up • Krummholtz “sub alpine” zone - stunted, dwarf trees, often flagged • Alpine zone - above treeline (grasses, lichens, specialized plants)‏ • Drastic changes in plant communities and forest structure

  4. Alpine Communities • Very rare (<5% of terrestrial habitat on planet)‏ • Very similar species to tundra biomes • Mount Washington biggest alpine zone east of Mississippi (Mt. Katahdin is second). • Plants remenants of last glacial retreat (9000 years ago)‏ • Very fragile (easily trampled by humans)‏ • Endemic plant species present • Threated by warming trend (global warming)‏

  5. Alpine Vegetation • Low lying (cushions) for protection against snow • Have thick, waxy leaves to prevent wind/snow damage • Alpine plants can tolerate extremes in environment (drying winds, acidic soils, scant water, ice coating)‏ • Evergreen leaves to save energy of foliation in spring

  6. Moss CampionSilene acaulis

  7. Alpine Azalea

  8. Diapensia lappocona

  9. Cladina stellarisStar-tipped reindeer lichen • Lichen - mutualism between algae and fungi • Attaches to hard substrates (rocks, trees)‏ • Nutrients from air and photosythesis • Bioindicator • Cladina stellaris important food for caribou

  10. Birds of the Alpine Zone • American Pipit • Rare in the East • Only nests on Katahdin and Presidentials

  11. Mammals • Caribou once roamed throughout New England’s alpine zones • Extirpated by turn of century • Reintroduction to Baxter State Park failed in 1980s

  12. What we will do on Bald Face? • Measure canopy height • Measure % canopy cover and light intensity • Record tree species and diameter (dbh) in 10x10 meter plots • Collect a soil sample and measure horizons • Record height and % cover of forest layers (herbacious, shrub, subcanopy, canopy)‏ • Identify plant species (herbs, shrub, fern, etc)‏ • Determine Stand Age • Incidental mammals, herps, birds

More Related