Presentation on theme: "Chapter 3 Communities, Biomes and Ecosystems"— Presentation transcript:
1 Chapter 3 Communities, Biomes and Ecosystems 3.1 Community Ecology
2 Communities All the interacting populations in an ecosystem A biological community is a group of interacting populations that occupy the same area at the same time.Abiotic and biotic factors interact and result in condition that are suitable for life for some organisms and unsuitable for other organisms
3 Limiting FactorsEnvironmental factors (abiotic or biotic) that restricts existence, numbers, reproduction or distribution of organismsFood, predators, temperature, light…
4 Limiting FactorsFactors that limit one organism may indirectly limit othersWhat happens when the number of grasshoppers is reduced?
5 ToleranceAbility of an organism to withstand fluctuation in biotic and abiotic factors
7 Ecological Succession Orderly, natural changes and species replacement that take place in the communities of an ecosystemPrimary SuccessionAfter volcano or avalancheStart with rock (no soil)Secondary SuccessionAfter forest fire or abandoned farmlandStart with soil
9 Primary SuccessionPioneer Species: first species on bare land/rock is lichen or mossBreakdown of rock and decay of moss will build up the soil so other plants can surviveOvertime additional habitats develop
10 Primary Succession Producers are always present before consumer Ends with climax communityStable, mature community which undergoes little or no change in speciesCan take hundreds of years to develop a climax community starting with rock
12 Secondary SuccessionSequence of community changes that take place after a community is disrupted by natural disasters or human actionsOccurs in places that previously contained lifeOn land that contains soil, so takes less time than primary succession to reach climax community
14 Chapter 3 Communities, Biomes and Ecosystems 3.2 Terrestrial Biomes
15 Effects of Latitude and Climate Weather is the condition of the atmosphere at a specific place and time.One of the keys to understanding these communities is to be aware of latitude and climatic conditions.
16 Effects of Latitude and Climate The distance of any point on the surface of Earth north or south from the equator is latitude.
17 Effects of Latitude and Climate The average weather conditions in an area, including temperature and precipitation, describe the area’s climate.The graph shows how temperature and precipitation influence the communities.
18 Effects of Latitude and Climate Biomes are classified by their plants, temperature, and precipitation.
19 BiomesLarge group of ecosystems that share the same type of climax communityIdentified by climax community of plants rather than animals because plants don’t migrate.Plants are a better indicator of long term characteristics of a biome
21 Terrestrial Biomes From the North Pole TundraTaigaTemperate ForestGrasslandDesertTropical Rain ForestEach have characteristic abiotic and biotic factors
22 Aquatic EcosystemsTemperature and precipitation reflect its associated terrestrial biomeFreshwater biomesLakes, streams, rivers, pondsMarine BiomesOceans and seasStudy by amount of sunlightSpecialty biomes: estuary and intertidal zoneIntertidal zone
23 Freshwater Ecosystems Only about 2.5 percent of the water on Earth is freshwater.
24 Freshwater Ecosystems The characteristics of rivers and streams change during the journey from the source to the mouth.
25 Freshwater Ecosystems Fast-moving rivers and streams prevent much accumulation of organic materials and sediment.Usually, there are fewer species living in the rapid waters.In slow-moving water, insect larvae are the primary food source for many fish, including American eel, brown bullhead catfish, and trout.
26 Freshwater Ecosystems The temperature of lakes and ponds varies depending on the season.
27 Transitional Aquatic Ecosystems Areas of land such as marshes, swamps, and bogs that are saturated with water and that support aquatic plants are called wetlands
28 Marine EcosystemsThe intertidal zone is a narrow band where the ocean meets land.Communities are constantly changing in this environment as a result of disturbance.
29 Open Ocean SystemsThe photic zone is shallow enough that sunlight is able to penetrate.Below the photic zone lies the aphotic zone—an area where sunlight is unable to penetrate.The benthic zone is an area along the ocean floor that consists of sand, silt, and dead organisms.