Ecology and the Biosphere (Chapter 52)

( Psalm 104:10-13He makes springs pour water into the ravines; it flows between the mountains.

They give water to all the beasts of the field; the wild donkeys quench their thirst.

The birds of the air nest by the waters; they sing among the branches.

He waters the mountains from his upper chambers; the earth is satisfied by the fruit of his work.Ecology is about INTERACTIONS

Ecology: [oikos = home; logos = study] the study of how organisms interact with each other and their environmentSix levels of ECOLOGY (Fig. 52.2)

1. Organismal ecology: interactions of an individual organism with its environment

2. Population ecology: group of individuals of the same species

3. Community ecology: assemblages of populations of different species

4. Ecosystem ecology: includes all abiotic factors as well

5. Landscape ecology: factors controlling different types of patches

6. Global ecology: regional exchange of energy and materials across the biosphere

Ecologists vs. environmentalists

Whats the difference? Environmentalist protects the environment and ecologist studies it Can an ecologist be an environmentalist? Yes e.g., Rachel Carson published Silent Spring in 1962 based on data from her work as a government scientist

Where is home (Oikos)?

No organism is at home anywhere what limits their distribution?

Where is home (Oikos)?

As Fig. 52.17 shows, the semi-aquatic wood turtle is only found in a narrow latitudinal range in Eastern North America Is temperature the only factor limiting its range?Three major types of factors may limit the distribution of organisms:

1. Dispersal: Fig. 52.20 (recent cattle egret dispersal throughout the world)

2. Abiotic factors: e.g., temperature as in the case of the semi-aquatic wood turtle3. Biotic factors: e.g., humans have created large areas throughout the world more suitable for cattle egrets Terrestrial Biomes

Although the dominant ecosystem = coniferous forest many terrestrial biomes found in B.C.

Coastal area: temperate coniferous rainforest

More inland: Ponderosa pine forest ( dry grassland ( desert (e.g., Osoyoos area)

High altitude: like the tundraPacific Regional Society of Soil Science field trip to the BC Interior, Sept. 2009

Subalpine forest Manning Park

Ponderosa pine forest BC interior

Canadas pocket desert southern Okanagan valley On a map biomes are drawn with distinct boundaries, but in nature biomes grade into one another

Area of intergradation called an ecotone Many biomes no longer exist in their original forms, e.g., temperate forests in eastern North America, temperate perennial grasslandsAquatic Biomes

Occupy the largest part of the biosphere (oceans = 75% of earths surface)

Both marine and freshwater biomes tend to be physically and chemically stratified Key layers: photic zone, aphotic zone, benthic zone

Marine Biomes

Most productive zones = intertidal zones and coral reefs (vs. the desert of the oceanic pelagic biome)

Intertidal zone off B.C. and Washington coast one of the highest areas of species diversity in the world1