This material is based on work supported by an Environmental Literacy Grant from the
National Oceanic and Atmospheric Administration's Office of Education
(NA0909SEC4690009) and prior work supported by the National Science Foundation
under Grants ANT-0342484 and ESI-0632175. Any opinions, findings, and conclusions or
recommendations expressed in these materials are those of the authors and do not
necessarily reflect the views of the NOAA or the NSF.
Where Have all
the Biomes Gone?
ELF Activity: 1B
http://andrill.org/education/elf_activities_1B.html
As part of NOAA Environmental Literacy Grant
#NA09SEC490009 to the University of Nebraska–Lincoln's,
ANDRILL Science Management Office.
Biomes are the world's major natural communities, generally defined according to the
dominant vegetation. Organisms in a specific biome tend to have similar adaptive
characteristics; for example, they might be able to tolerate drought, low temperatures, short
growing seasons or high winds.
Throughout the history of the Earth, biomes have
shifted as regional climates have changed. Now,
human activities are beginning to alter the factors
that influence biomes. As the Earth’s climate
changes, biomes are shifting and organisms must
adapt or move; otherwise, they will die out.
Biomes vary with latitude and region. For instance, tree line determines the elevation
above which trees will stop growing due to harsh climate factors. Tree line occurs at
different elevations depending on latitude.
Observe the following table
and note the general trend of
lower tree line elevation with
increasing latitude.
Location
Latitude
Tree line m/ft
Costa Rica
90N
3400/11,200
Hawaii
200N
2800/9200
Sierra Nevada, CA
380N
3200/10,500
Maine
460N
1150/3770
Alaska
610N
700/2300
With some exceptions the worldwide trend is, “The higher
the latitude, the lower the tree line.”
What are Hotspots?
Hotspots refer to regions of high biodiversity which are currently experiencing
loss of habitat.
For example: California
This state has hot dry summers and cool moist winters and contains several
ecosystems. Of the 3500 native plants, 2100 (60%) are found nowhere else on the
planet. 50% of the amphibians and 11% of the mammals are also endemic.
Only 37% of the land is protected. Human development (both urban and
agriculture) threatens many of these species.
There are only 25 biodiversity hot spots throughout the world.
The following slides introduce the major
biomes of the world.
Warm and Very Wet – Tropical Rainforest
Found mainly between 10o N and 10o S.
Abundant rainfall and year-round warmth.
This biome is the most complex and hosts
the greatest biodiversity. Dominated by
large broadleaf trees, ferns, vines, colorful
birds, and an abundance of species of
mammals, amphibians, and insects.
Warm and Semi-Wet – Grasslands
Temperate areas, 10-20 inches of rain
per year, warm to hot summers.
Dominated by perennial grasses. Bison,
pronghorn antelope, ground squirrels,
prairie dogs, coyotes, mice, rabbits,
sage grouse, and many songbirds.
Warm and Dry – Desert
Less than 10 inches of rain per year;
temperatures may reach above 100oF in
summer. Shrubs have small thick leaves.
Plants and animals adapted to tolerate
high temperatures and sparse water
resources. Animals mostly nocturnal and
light-colored to reflect the sunlight.
Cool and Wet – Broadleaf Forest
20-60 inches of precipitation per year. Warm summers,
cold winters. Deciduous trees dominate the region with
some conifers. Oak, elm, maple, beech, and hickory are
common. Shrubs , flowering herbs with ground lichen
and moss add to the biodiversity of this biome. Bears,
deer, squirrels, chipmunks, skunks, raccoons, and many
seed- and insect-eating birds.
Cold and Wet – Pine Forest
Cold long winters and wet summers. Dominated
by conifers (pine, fir, spruce), with some
broadleaf trees (alder, birch aspen). Abundant
migratory birds and fur-bearing mammals
(martens, bears, lynx, squirrels, voles, weasels,
beavers). Large herbivores include elk, moose,
and deer.
Cold and Wet – Arctic Alpine
Similar to the Arctic Tundra except receives
more precipitation. Found at higher
elevations in the middle and lower latitudes.
Mosses, lichens, grasses, low shrubs; no trees
above tree line. Mammals include picas,
marmots, migratory birds, and small rodents.
Cold and Dry – Tundra
Cold, long, dark winters; low precipitation. Treeless land with few species. Lichens, mosses,
sedges, heath, and low shrubs. Ptarmigans, muskoxen, arctic hares, arctic foxes.
High latitudes in the Northern Hemisphere.
Wet – Marine
Ocean environments found worldwide.
Highly diverse depending on water
temperature, depth, and presence of
nutrients.
In this activity, students sort organisms into the world’s biomes
based on their knowledge or on the organism’s adaptive
characteristics which make it suitable to live in that biome.
Then students sort fossil organisms into the Earth’s current biomes.
When it is revealed where the fossils were actual found, students
see that the world’s biomes have not always been in the same place.
All photos in this slide presentation are courtesy of
the U.S. Bureau of Land Management:
http://www.blm.gov/wo/st/en/bpd.html
This material is based on work supported by an Environmental Literacy Grant from
the National Oceanic and Atmospheric Administration’s Office of Education
(NA09SEC4690009) and prior work supported by the National Science Foundation
under Grants ANT-0342484 and ESI-0632175. Any opinions, findings, and
conclusions or recommendations expressed in these materials are those of the
authors and do not necessarily reflect the views of the National Oceanic and
Atmospheric Administration or the National Science Foundation.
http://andrill.org/education/elf/activities