Chapter 52 An Introduction to Ecology and the Biosphere
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Transcript of Chapter 52 An Introduction to Ecology and the Biosphere
Chapter 52An Introduction to Ecology and the Biosphere
2.d.1 – All biological systems from cells and organisms to populations, communities, and ecosystems are affected by complex biotic and abiotic interaction involving exchange of matter and free energy (52.2).
Essential Knowledge
The study of the interactions between organisms and their environment
Ecology
All living beings (animals, plants, fungi, etc)
Studied at many different levels
Organisms
1. Organismal Ecology2. Population Ecology3. Community Ecology4. Biome Ecology5. Biosphere Ecology
Ecology - levels
Abiotic Factors: nonliving factors Ex: Temperature, water, wind, humidity
Biotic Factors: living factors Ex: Competition, Predation (plants, animals, fungi,
etc)
Environment
1. Temperature2. Water 3. Sunlight4. Wind5. Rocks and Soil6. Disturbance
Abiotic Factors
Effects cell contents Ex:
◦ Cold – cells will rupture if temperatures drop below a certain point
◦ Hot – many proteins and DNA will denature Point – life can only exist over a fairly
narrow temperature range
Temperature
Review the properties of water from Chapter 3.
Cells must maintain a certain water potential level (keep from exploding or drying out).
Water
Provides energy for Ps, which drives most food webs.
Plants often compete for light because of shading or absorption of light by deep columns of water.
Sunlight
Effects temperature and water conditions for many organisms.
May carry abrasive particles that limit plant growth by killing the SAM areas.◦ SAM??? Shoot apical meristem areas
Wind
Physical structure, pH, mineral composition of rocks and soil limit where plants can grow.
Ex. Se soils. Plants limit what animals can be found in an
area.
Rocks and Soil
Disturbance is often an important part of an environment.
Allows organisms to re-colonize an area. Ex: Fire
Humans Wind
Disturbance
Yellowstone Fire
Shapes environments and what organisms can live in a particular area.
Climatic factors:◦ Solar radiation and latitude◦ Axis tilt/seasons◦ Air/Water circulation patterns
Climate
Changes the amount of light and energy delivered per surface area.
Result:◦ Poles: less light◦ Equator: more light◦ Unequal heating causes air and water to circulate
Solar Radiation and Latitude
Caused by the Earth's tilt. Day length changes over time. Many organisms are restricted in range by
how well they adapt to changing seasons.
Seasons
Air rises when heated, sinks when cools. Zones of rising/sinking are created. Earth's rotation causes zones to "twist”. Result:
◦ Air circulation patterns◦ Rain fall patterns
Rising air: wet areas Descending air: dry areas
Global Air Patterns
Broad geographical regions with characteristic communities of organisms.
Biomes are controlled by:◦ Temperature◦ Water amount and proximity◦ Geography
Biomes
Areas covered with dense/lush growth of trees and vines.
Climate:◦ Warm temperatures.◦ Constant day length.◦ High water.
Vertical layers of autotrophic growth
Tropical Forests
Have the greatest diversity of species of any area on Earth.
Soil is usually very infertile. Most of the nutrients are in the plant life.
One of the most endangered Biomes.
Tropical Forests
Tropical Forests
Grasslands with a few trees. Climate with three growing seasons:
◦ Cool and dry◦ Hot and dry◦ Warm and wet
Rich in herbivores and predator species Only major biome not found in North
America
Savanna
Characterized by plants adapted to dry growing conditions.◦ Cacti, succulents
Climate:◦ Dry (<30cm/yr).◦ May be cold or hot.
Often found in areas of descending air masses.
Low productivity, but still fairly diverse in species.
Desert
Characterized by spiny evergreen shrubs. Climate:
◦ Mild rainy winters◦ Hot summers
Ex: Southern California Maintained by fires Plants adapted to periodic fires by seeds or
re-growing from the roots
Chaparral
Grasses and other herbs are the dominant vegetation.
Indiana could be considered a temp. grassland
Climate:◦ Intermediate water◦ Relatively cold winters
Temperate Grasslands
Very productive for agriculture. (wheat, corn)
Need disturbance (fires) to keep trees out.
Come in several types:◦ Tall grass◦ Short grass
Grasslands
Deciduous trees dominate (often called deciduous forest)
Climate:◦ Relatively high rain◦ Cold winters
Very little natural area left. Good diversity of species. Coniferous forest:
◦ Tall stands of cone-bearing tress
Temperate Forests
Coniferous trees dominate (also called coniferous forests)
Climate:◦ Long cold winters◦ Short wet summers◦ Long summer daylength
Relatively low species diversity Being logged at an alarming rate
(disappearing rapidly!)
Taiga (Boreal forest)
Grasses and sedges dominate. Climate:
◦ Very cold and dry◦ Low light in winter
Permafrost present Plants low in height Poor species diversity
Tundra
Mirror each other. Their Biomes are similar because the
environments are similar. Ex: Alpine = Tundra
Altitude and Latitude
Aquatic Biomes
Have <1% salt concentration. Strongly influenced by temperature and
light. Classification – based on water flow
patterns. Flowing: rivers, creeks Non-flowing: ponds, lakes
Fresh water Biomes
Cover 3/4 of the Earth's surface. Average 3% salt. Controlled by light and the distance to the
shore.
Marine Biomes
Photic - Enough light for Ps. Red light lost rapidly as depth increases.
Aphotic - Lacks enough light for Ps and depends on food made in photic zone for energy. Part of the most extensive biome on the planet.
Light Zones
1. Estuaries2. Intertidal3. Coral Reefs4. Pelagic5. Benthos
Marine Biomes
Where a freshwater river meets the ocean.
Salinity variable.
Very productive Biome.
Complex flow patterns
Estuaries
Characterized by coral.
Found in shallow warm waters.
Very productive. High species
diversity. Very sensitive to
temperature changes
Coral Reef
Bottom area. Usually fed by nutrients drifting down from
upper levels. Fairly rich in life.
Benthos
Know what is involved with the study of “Ecology”.
Know the major factors of planet Earth that shape climate.
Know the major terrestrial biomes and the factors that control them.
Know the major types of aquatic biomes and the factors that control them.
Summary