Download Introduction to Ecology

Introduction to Ecology
Part III
What is a biome?
 Are distinguished by the presence of characteristic plants and animals
 Commonly identified by their dominant plant life
 Biomes are distributed over the Earth based on climate (temperature and
precipitation) and latitude
8 major categories of Major Biomes
 Tundra
 Tropical forest
 Temperate forest
 Taiga
 Temperate grasslands
 Savanna
 Chaparral
 Desert
 Tundra:
o Description:
 Cold and largely treeless biome that forms a continuous belt
across northern North America, Europe, and Asia
o Largest northernmost biome (covers 1/5 of the world’s surface)
o Temperature:
 -26 0C to 12 0C
o Precipitation:
 Less than 25 cm/ year
o Soil:
 Moist, thin topsoil over permafrost; low in nutrients; slightly
acidic
 Soil above permafrost remains frozen for all but 8 weeks a year
o Vegetation:
 Mosses, lichens, grasses, and dwarf woody plants
o Animals:
 Caribou, musk oxen, snowy owls, arctic foxes, lemmings, and
snowshoe hares
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 Tropical forest
o Near the equator (between 23.5ON and 23.5OS)
o Includes parts of Asia, Africa, S. America, and Central America
o Have two seasons (tropical rain and tropical dry forests)
o Temperature:
 6OC to 14OC
o **Most productive biome**
o Precipitation:
 200-400 cm/year
o Soil:
 Moist, moderately thick topsoil, moderate nutrients
o Vegetation:
 Broad-leaved evergreen trees and shrubs
 Mostly made of trees 50-60 meters tall stretching its canopy shading
the forest floor
 Creating a virtual plant free floor
 Small plants live on the branches called epiphytes (mosses,
orchids, and bromeliads)
o Highest species richness
 300 different species of trees per hectare
 more than 1 million species of tree beetles
 Contains ½ of the world’s species
o Animals:
 Monkeys, snakes, lizards, parrots, insects, etc.
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 Temperate forest
o Occur in N. America, western and central Europe, and Northeastern
Asia
o Has distinct seasons and moderate climate
o Temperature:
 6 OC to 28 OC
o Precipitation:
 75 – 125 cm/ yearly
o Soil:
 Moderately thick topsoil, moderate nutrient levels
o Vegetation
 Broad-leaved deciduous trees (maple, oaks, beech, willow, and
birch)
 Shrubs (ferns, herbs, and mosses)
 Evergreen coniferous trees (evergreens, spruce, other pines)
o Animals:
 Bears, wolves, white-tailed deer, foxes, raccoons, and squirrels
 Taiga
o Is south of the tundra and north of the temperate regions
o Span across N. Europe, Asia, and North America just below the arctic circle
o Temperature:
 Long winters, short summers
 -10OC to 14OC
o Precipitation:
 35 – 75 cm/year
o Soil
 Low nutrients, highly acidic
o Vegetation
 Coniferous evergreen trees (spruces, firs, and pines)
o Animals
 Moose, bears, wolves, lynxes, and hares
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 Temperate grasslands
o Covers large areas of N. America, Asia, Europe, Australia, and S. America
o Forms interior of the continents
o Temperature:
 0OC to 25OC
o Precipitation:
 25 – 75 cm/year
o Soil:
 Deep layer of topsoil; very rich in nutrients
o Vegetation:
 Very few trees
 Dense, tall grasses in most areas
 Short grasses in drier areas
 Mainly farming and grazing areas
o Animals
 Bison, Buffalo, and horses
 Savanna
o Parts of Africa, W. India, N. Australia and some S. America
o Located in tropical and subtropical areas near equator and between
tropical forest and desert biome
o Temperature:
 16OC – 34OC
o Precipitation:
 75 – 150 cm/ year
o Soil:
 Dry, thin topsoil,
 Porous and low in nutrients
o Vegetation
 Tall grasses with horizontal roots
 Scattered trees
 Often leaves that are sharp and thorny
o Animals
 Elephants, black/white rhinos, giraffes, and zebras
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 Chaparral
o Primarily located on coastal areas with Mediterranean climates
o California (“Hollywood” sign)
o Temperature:
 10OC to 18OC
o Precipitation:
 Less than 25 cm/year (9.9 inches)
 Warm dry summers, and mild wet winters
o Soil:
 Rocky, thin topsoil
 Low in nutrients
o Vegetation
 Evergreen shrubs, and small trees
 Chamise, scrub oaks, olive trees, herbs (sage and bay)
 Leaves small and leathery with lots of oils
o Animals
 Quail, lizards, chipmunks, and mule deer
 Desert
o Temperature:
 7OC to 38OC
o Precipitation:
 Less than 25 cm/year (9.9 inches)
o Soil
 Dry, often sandy, low in nutrients
o Vegetation
 Little to no vegetation
 Succulent plants and scattered grasses
 Cactus – can drop water levels below 50-75% (fatal for
other plants)
o Animals:
 Reptiles - (Gila monster), rattle snakes
 Amphibians – spadefoot toad burrow underground
 Elf owl, (burrow into cactus), desert insects and spiders (nocturnal)
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Aquatic Ecosystems:
 Ecosystem of Fresh and Salt water
 Major oceans:
o Average of 2.3 – 6.8 miles deep
o Atlantic and Pacific Oceans
 Estuaries:
o Where fresh water from a river mixes with salt water from the ocean
o Estuaries include Chesapeake Bay (Is the largest estuary in the U.S.), bays,
mud flats, mangrove swamps, and salt marshes
 Rivers and streams:
o Originate from snow melt (starting as streams)
o Cold and full of oxygen that run toward a mouth to become wider and
deeper forming a river
o Example: Mississippi river
 Freshwater wetlands:
o Areas of land that are covered with freshwater for at least part of each
year
o Swamps – dominated by woody plants (trees, and shrubs)
o Marshes – nonwoody plants (cattails)
o Most important wetland in the world is the Florida Everglades
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Part III Question review questions
1. List at least one animal that lives in each of the eight major biomes
2. Compare the level of biodiversity in a tropical rain forest with that in a temperate
deciduous forest
3. Why do so few trees grow in the tundra?
4. Where in the world could you travel to see savanna? Chaparral?
5. Describe three adaptations of desert organisms for water conservation
6. For deciduous trees, compare the benefits and possible disadvantages of shedding
leaves in the fall
7. Discuss the differences between tundra and taiga
8. What could happen to fast moving organisms that live in a fast-moving river if a
dam were built on the river?
9. Describe some reasons why freshwater wetlands considered to be economically
and environmentally important?