Chapter 4

Communities and Biomes

Community Distribution

Limiting Factor – any biotic or abiotic factor that restricts an organism (ex. Food, water, shelter..)

Range of tolerance – when organism receives too much or too little of something (ex. Sun, water...)

1. What happened to the deer population over the years?2. What are possible reasons for what happened to the deer population?3. What do animals need to survive?4. Define “limiting factor.”5. What are some of the limiting factors that affect the deer’s survival?6. Are wildlife populations static, or do they tend to fluctuate as part of an overall “balance of nature?”7. Is nature ever really in “balance”, or are ecological systems constantly changing?

Climax community – a stable mature community that undergoes little or no succession (example: a mature Oak Forest)

Succession – orderly, natural changes in a community over time

Pioneer species – first inhabiters of an area (moss, lichens)Primary (1) Succession - first colonization of a new land (lava flow, stream deposit, strip mine)

Secondary (2) succession - sequence of changes that happen after a community is disrupted by natural disasters (forest fire, hurricane, flood) or by human actions (agriculture, clear cutting forest)

Biomes – a large group of ecosystems that share the same type

of climax community

Aquatic biome – biome of water (river, lake, ocean, stream)

Marine biome – the ocean covers nearly 75% of the earth’s surface

Plankton –producers of the ocean, generally microscopic

Photic zone – layer of the water that is shallow enough that light can pass through

Aphotic zone – layer of water that is deep enough that it never receives light

Marine Zones

Photic

Aphotic

Estuary – water (such as at the mouth of a river) where fresh water and salt water mix (brackish water)

Estuaries are often associated with high rates of biological productivity.

Tidal zone (intertidal zone) – is where the land and sea meet, between the high and low tide zones. This complex marine ecosystem is found along coastlines worldwide. It is rich in

nutrients and oxygen and is home to a variety of organisms

Much of this inhospitable environment is washed by the tides each day, so organisms that live here are adapted to huge daily changes in moisture, temperature, turbulence (from the water), and salinity.

Most livings are near the surface of fresh water where the water stays warmer and the light is able to penetrate the water

Freshwater biome – a water biome that does not contain much salt; lakes, ponds, rivers

Terrestrial biome – biome on land

        Temperature         Precipitation

Two major factors influence the type of biome that exist on land

Biome Graph Precipitation vs Temp.

"Original" Whittaker diagram

"Modified" Whittaker diagram

Place Average Temperature oCAnnual Precipitation

(cm) Biome

La Selva, Costa Rica 22.1 403 Tropical Rain Forest

Marietta, Ohio 12 105Temperate Deciduous Forest

Pasadena California 18.2 51.8 Savanna

Ferron, Utah 8.8 20.9 Desert

Tucson, Arizona 21.1 21.9 Subtropical Desert

Santa Rosa, Costa Rica 26 165 Tropical Seasonal Forest

Brazzaville, Congo 25 137 Tropical Seasonal Forest

Lambarene, Gabon 25.7 195 Tropical Seasonal Forest

Amauulu, Hawaii 20 410 Tropical Rain Forest

Toolik Lake, Alaska -8.8 18 Tundra

Beijing, China 11.8 63.5 Temperate Grassland

Seoul, South Korea 11.2 137Temperate Deciduous Forest

Archbold Biological Station

29.1 131 Tropical Seasonal Forest*

Everglades National Park (Flamingo)

28.1 159 Tropical Seasonal Forest*

NOTE: Use “original” diagram

Terrestrial Biome Map

Tundra

It has poor soil due to the weather and small plants and animals because of the lack of protection and short growing seasons

Tundra – treeless land with long summer days and below 0C much of the year.Permafrost – because of the cold temperatures the ground never thaws more than a few inches deep the layer under the thawed layer remains frozen year round (permanently frozen)People have found remains of even extinct animals in the permafrost (a woolly mammoth)

10 000-year-old baby mammoth has been unearthed in a remote northern Siberian region

Taiga

Taiga (Northern Coniferous Forest) – water logged soil, it lacks permafrost and has acidic soil due to pine needles. There is more shelter (trees) and large plants which allows for larger animals

Desert

Desert – Annual rainfall 0 to 25cm. Plants vary with the amount of rain from small shrubs to nothing at all. Most animals are small and remain under cover during the day to escape the hot sun.

Grasslands

Grassland – 25 to 75 cm of rain annually. It is covered with grasses and small plants.There is more biodiversity than deserts because of the more water.It is ideal for growing grains in the rich soil.

Temperate Forest

Temperate forests – 70 to 150 cm per year. Usually there is a rich top layer of soil and a deeper layer of clay. Plants include broad-leaf trees.Many animals live in the forest year round others migrate south.

You live here!!!

Tropical Rain Forest

Tropical Rain Forest – Receives 200 to 400 cm of rain per year. Most nutrients are tied up in the living material.The roots are usually shallow because of the thin, poor soil. This is the most biologically diverse of all the biomes