ecosystems and communities chapter 4. 4–1 the role of climate
TRANSCRIPT
Ecosystems and CommunitiesChapter 4
4–1 The Role of Climate
Objectives• Identify the causes of climate
• Explain how Earth’s temperature is maintained
• Identify Earth’s three main climate zones
Weather
• The day to day condition of earth’s atmosphere at a particular time and place
Climate • The average, year after year
condition of temperature and precipitation in a particular region
• Caused by an interplay of many factors especially incoming sunlight
The Greenhouse Effect• Carbon dioxide, methane, water
vapor, and a few other atmospheric gases trap heat energy and maintain Earth’s temperature range.
• Just as the glass keeps the greenhouse plants warm, so these gases trap the heat energy of sunlight inside Earth’s atmosphere.
Greenhouse effect • The natural situation in which
heat is retained by this layer of greenhouse gases
Greenhouse effect
Infrared Radiation
Sun Rays
Atmosphere Containing Green House Gasses
The Sun
Temp within limits for life
Infrared Radiation
Sun Rays
Atmosphere Containing Extra Green House Gasses
*
The Effect of Latitude on Climate
• Because Earth is a sphere that is tilted on its axis, solar radiation strikes different parts of Earth’s surface at an angle that varies throughout the year.
The Effect of Latitude on Climate
The Effect of Latitude on Climate
• As a result of differences in latitude and thus the angle of heating, Earth has three main climate zones: polar, temperate, and tropical.
The more direct the rays are the ________________ an area of land will heat up.
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4–2 What Shapes an Ecosystem?
Objectives• Explain how biotic and abiotic
factors influence an ecosystem
• Identify the interactions that occur within communities
• Describe how ecosystems recover from a disturbance
biotic• Living factors of an environment
abiotic• The non-living factors of an
environment
Ex.) water, soil, air
• Together, biotic and abiotic factors determine the survival and growth of an organism and the productivity of the ecosystem in which the organism lives
Habitat• Where an organism lives
Squirrel in tree
Fish in stream
Niche• The role an organism plays in its
environment
• A niche is the full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions.
• No two species can share the same niche in the same habitat
Community Interactions• Community interactions, such as
competition, predation, and various forms of symbiosis, can powerfully affect an ecosystem.
Competition• Competition occurs when organisms
of the same or different species attempt to use an ecological resource in the same place at the same time
• Direct competition in nature often results in a winner and a loser—with the losing organism failing to survive
Competitive exclusion principle
• States that no two species can occupy the same niche in the same habitat at the same time
Predation• When one organism captures and
feeds on another organism
• The organism that does the killing and eating is called the Predator, and the food organism is the Prey.
Symbiosis• Any relationship in which two
species live closely together
• Biologists recognize three main classes of symbiotic relationships in nature
Mutualism
• When both members benefit
Ant – Acacia Tree
Commensalism• When one member benefits and
the other is neither helped nor harmed
Clownfish – Sea Anemone
Parasitism• When one member benefits and
the other is harmed
Humans - Tapeworms
Ecological Succession• Ecosystems are constantly changing
in response to natural and human disturbances. As an ecosystem changes, older inhabitants gradually die out and new organisms move in, causing further changes in the community.
• The series of predictable changes that occurs in a community over time
Primary Succession
• Succession that occurs on new land where no soil exists
Ex.) volcanic islands, bare exposed rock when glaciers melt
pioneer species
• The first species to populate an area
Ex.) lichen, algae, mosses
Secondary Succession
• When a disturbed area grows back to normal
Ex.) natural disaster areas
4–3 Land Biomes
Objectives• Identify the characteristics of
major land biomes
Biomes • Large geographical areas that
have similar climates and characteristics