BACKGROUND:
There are many kinds of ecosystems on this Earth
because of the many possible combinations of climate, soil, parent rock,
water, temperature, currents, and biological life. There are
terrestrial, fresh water, and marine ecosystems. This activity
will concentrate on the terrestrial ecosystems and their biome divisions.
A biome is a large geographical region identified mainly by its vegetation
caused by similar climate. There are a few ways to classify terrestrial
biomes. These lesson will use the following biome classification
used on the inflatable globes.
Tundra - Wet country beyond the timberline in both the
Eurasian Arctic and the American Arctic. A treeless, marshy plain with
grasses, sedges, lichens, rocks, and water.
Desert - Occupies climates too dry for grasslands. Vegetation
consists of widely scattered thorny bushes, perhaps a few succulents such
as cacti. Drought is a limiting factor, and can include warm or cold deserts.
Tropical Rain Forest - Plenty of moisture and heat, no drought
and no winter. Great diversity of animals and plants. Best developed
in tropical Americas, particularly the Amazon basin in Brazil, in the East
Indies and surrounding areas, and lesser extent in Africa.
Forest - Community of plants and animals in which the most
dominant members are a variety of trees. There are many different species
of trees that comprise different forest areas. Deciduous forest are those
trees that shed their leaves annually. Coniferous forest have needle-like
leaves and are evergreen.
Prairie/Savanna/Grasslands - Grasslands often dotted with trees
or small patches of forest. Some are dry, others are wetter, warm all year
round with dry seasons and cool seasons. The drier climates are usually
called Savanna and are located in Central America (Pacific coast), Central
and East Africa, India, Southeast Asia, and northern Australia. Temperate
grasslands have more water evenly distributed throughout the year.
Located in Central North America, Eastern Europe, Central and Western Asia,
Argentina, and New Zealand.
Mediterranean - Mild, damp winters but hot, dry summers with
blue skies and seldom a drop of rain. Vegetation varies from dense
spiny scrub to open grassy woodlands. Located in southern France,
Spain, Portugal, North Africa, Israel, Lebanon, Italy, California, southwestern
Australia, Cape of Good Hope in South Africa, and in central Chile.
Mountain Flora and Moorland - High altitude with sparse flora.
Cold all year round, with some thawing.
Ice/Snow - Areas that are covered by snow all year round.
Vegetation is almost nonexistent. Organisms are sparse and cold tolerant.
PROCEDURE:
- Discuss with students the different
terrestrial biomes described in the “Background” section. You may
want to give students a globe and have them list the biomes on the board
and then proceed to define each one. A biome is a rather broad category
with considerable variation around the Earth, but it includes an area of
the earth that has similar physical and/or biological characteristics.
The inflatable globe divisions are a blend of the two.
- As a homework assignment, have student find
pictures of different organisms. These pictures will be needed for
the lab. Students should research where these organisms are from.
For example, if they bring in a picture of a rainforest, make sure they
identify where the picture was taken. In lab, the students
will try to figure out where all the organisms belong on the inflatable
globe, and try and find organisms that are similar in the same biomes.
You will find out that this is not as easy as it sounds. There are many
different divisions of biomes, but it is important for students to
learn that it is not always cut and dry, the natural world is not as simple
as it seems!
