Density Independent Limiting Factor
Glacier Bay, sees little rainfall, and is frozen for much of the year. During the winter it is very cold and dark, with the average temperature around -18 °F, it can dip as low as -58 °F. During the summer, temperatures rise somewhat, and the top layer of the permafrost melts, leaving the ground soggy. The tundra is covered in marshes, lakes, bogs and streams during the warm months.
The soil of the arctic tundra is poor in nutrients, which accounts for the low amount of vegetation. There is an under-layer of soil called permafrost which remains completely frozen at all times, allowing little room for deep rooting plants and trees. Most of the arctic tundra's plant life consists of shrubbery, lichen, moss, and flowers. Icy rivers flow through the tundra to the arctic ocean, and are home to trout, salmon and other freshwater fish.
The biodiversity of the Glacier Bay has a low amount vascular plants and mammals, although thousands of insects and birds migrate there each year for the marshes. All of the animals are greatly adapted to their environment, with extra layers of fat, and the ability to hibernate during the colder months, although this has more to do with the lack of food than the cold. Birds of the Glacier Bay migrate south during the winter months, causing constant change in the animal population.
Density Dependent Limiting Factor
An independent factor of the Glacier Bay is global warming. Over the past 50 years Alaska's annual average temperature has increased at more than twice the rate of the rest of the United States' average, and here in Southeast Alaska winters are 5 degrees warmer. Glacier Bay is expected to become warmer and drier over the next century. Some of the effects that will be occurring Alaska include earlier spring snowmelt, reduced sea ice, shrinking glaciers, melting permafrost, bark beetle infestations, and more forest fires. There are over 100,000 glaciers in the state, 95% are currently thinning, stagnating, or retreating, and most of Glacier Bay's glaciers follow this. Glacier Bay still remains home to a few healthy and advancing glaciers, a rarity in today's world
Changing Habitat:
Other changes can be low species diversity, and loss of habitat. For example, salmon could be facing some hard times ahead. Heavy spring run-off can scour stream beds and destroy eggs, a diminished snow pack could reduce the number of spawning pools, and rising sea level could flood freshwater pools with salt water.
Ocean Acidification:
Oceans absorb CO2 also produce carbonic acid. This "ocean acidification" destroys the shells of some zoo-plankton the backbone of the marine ecosystem.
Changing Habitat:
Other changes can be low species diversity, and loss of habitat. For example, salmon could be facing some hard times ahead. Heavy spring run-off can scour stream beds and destroy eggs, a diminished snow pack could reduce the number of spawning pools, and rising sea level could flood freshwater pools with salt water.
Ocean Acidification:
Oceans absorb CO2 also produce carbonic acid. This "ocean acidification" destroys the shells of some zoo-plankton the backbone of the marine ecosystem.