Chapter 4 Ecosystems Communities Section 1 Climate Weather

Chapter 4: Ecosystems & Communities Section 1: Climate

Weather & Climate • Weather: day to day conditions of Earth’s atmosphere • Climate: average conditions over long periods • A region’s climate is defined by year after year patterns of temperature and precipitation

Factors that Affect Climate • Global climate is shaped by many factors, including solar energy trapped in the biosphere, latitude, and the transport of heat by winds and ocean currents • Greenhouse Effect: Gasses called greenhouse gases, function like glass in a greenhouse, allowing visible light to enter but trapping heat • As the greenhouse gas concentrations rise they continue to trap heat, so the Earth warms • Wind and ocean currents which transports heat and moisture throughout the biosphere

Chapter 4: Ecosystems & Communities Section 2: Niches & Community Interactions

Niches • Population: All the members of one species that live in a particular area • Community: All of the different species that live in a particular area • Habitat: place where an organism lives; physical location of a community • Niche: what an organism dos and how it interacts with biotic and abiotic factors in the environment • The range of physical and biological conditions in which a species lives and the way the species obtains what it needs to survive and reproduce • Resource: any necessity of life, such as water, nutrients, light, food, or space

• Competition: when different species fight over resources; this interaction can be harmful or detrimental to both species • Examples: • When Mc. Donald’s and Burger King compete, they both lose money • Two animals fighting over a food source • Competition can have several outcomes: • One species wins & the other loses • The loser is eliminated from the habitat • Competitors can survive together in the same habitat bc they divide resources • Competition can lead to extinction: when all the members of a species die • Competitive Exclusion Principle: states that no two species can occupy exactly the same niche in exactly the same habitat at exactly the same time • By causing species to divide resources, competition helps determine the number and kinds of species in a community and he niche each species occupies

Predation, Herbivory, & Keystone Species • Predation: an interaction between 2 organisms in which one organism(the predator) kills & feeds on the other organism(the prey) • Predators can affect the size of prey populations in a community and determine the places prey can live and feed • Herbivory: an interaction in which one animal (the herbivore) feeds on producers (such as plants) • Herbivores can affect both the size and distribution of plant populations in a community and determine the places that certain plants can survive and grow • Keystone Species: single species that is not usually abundant in a community yet exerts strong control on the structure of a community

Symbioses • Symbiosis: a relationship in which 2 different organisms live in close association with each other • There are 2 types of symbiosis: • Mutualism: a relationship between 2 species in which both species benefit • example: a bee pollinates a flower and the flower provides nectar for the bee • Commensalism: a relationship between 2 organisms in which one organism benefits & the other is unaffected • example: a buffalo moves through the grass forcing insects to move which then get eaten by birds • the bird benefits but the buffalo is unaffected • Parasitism: a relationship between 2 species in which one species(the parasite) benefits from the other species(the host) which is harmed • examples: leeches, ticks, fleas, lice, mosquitoes, and tapeworms • the difference between predation and parasitism is that in predation one individual is killed immediately, while in parasitism the parasite feeds on the host for a long time

Chapter 4: Ecosystems & Communities Section 3: Succession

Primary & Secondary Succession • Ecological Succession: a series of more or less predictable changes that occur in a community over time • Ecosystems change over time, especially after disturbances, as some species die out and new species move in • Succession: the gradual re-growth of species in an area after some disturbance • disturbances such as fires, landslides, hurricanes, and floods change the species diversity in communities • Over the course of succession, the number of different species present typically increase

�Primary Succession: the development of a community in an area that has not supported life before ◦ such as bare rock, sand dunes, or an island formed by volcanic eruption ◦ often occurs very slowly

Primary Succession

• Secondary Succession: the development of species that follows the disruption of an area where life previously existed • such as after a forest fire, strong storm, farming, logging, or mining • the soil is left intact

Secondary Succession

Chapter 4: Ecosystems & Communities Section 4: Biomes

Biomes �Biome: large region characterized by a specific type of climate and certain types of plants and communities. ◦ Biomes are described in terms of abiotic factors like climate and soil type, and biotic factors like plant and animal life

Terrestrial Biomes • • • Tropical Rain Forest (Page 112) Tropical Dry Forest (Page 112) Tropical Grassland/Savanna/Shrubland (Page 112) Desert (Page 113) Temperate Grassland (Page 113) Temperate Woodland & Shrubland (Page 113) Temperate Forest (page 114) Northwestern Coniferous Forest (Page 114) Boreal Forest (Page 114) Tundra (Page 115)

Other Land Areas • Because they are not easily defined in terms of typical community of plants and animals, mountain ranges and polar ice caps are not usually classified into biomes • Mountain Ranges • exist on all continents and in many biomes • conditions vary with elevation • Polar Ice Caps • boarder the Tundra and are cold year round • plants are few but some algae grows on ice and snow • when rocks and ground are exposed mosses and lichens may grow seasonally • Typical animals include marine mammals, insects, and mites • in the North(Arctic Ocean) where there is sea ice polar bears are found • in the South(Antarctica) where the ice can be nearly 5 km thick many species of penguins are found

Chapter 4: Ecosystems & Communities Section 5: Aquatic Ecosystems

Conditions Underwater • Aquatic organisms are affected primarily by the water’s depth, temperature, flow, and amount of dissolved nutrients

Freshwater Ecosystems • Freshwater Zones • Rivers & Streams • bodies of water that flow downhill • the type of organisms usually depends on the speed of the water flow • slower water can generally support more diverse life

• Lakes & Ponds • rich in organic matter, making them murky • mud bottoms

• Lakes & Ponds • little organic matter, making them clear • sand or rocky bottoms

• Wetlands • Wetland: an ecosystem in which water either covers the soil or is present at or near the surface for at least part of the year • Water can either flow through a wetland or stay in place • Nutrient rich and highly productive • Types: • Freshwater Bogs • Freshwater Marshes • Freshwater Swamps • Saltwater Wetlands are called Estuaries

Saltwater Ecosystems • Estuaries • occur where freshwater rivers flow into the sea; mix of fresh water and salt water • includes bays, mud flats, salt marshes • rivers deposit mineral nutrients • most species can adapt to the rapidly changing conditions • Serve as spawning and nursery grounds for many ecologically important fish and shellfish species

�Marine Zones ◦ Intertidal Zone �alternates between submerged and exposed as tides shift �organisms must be able to withstand crashing waves �crabs, clams, oysters, sea anemones, sea stars ◦ Neritic Zone �most productive ocean zone �water is shallow enough for photosynthesis to occur �plankton, fish, squid, turtles, coral reefs, crustaceans

�Marine Zones ◦ Photic Zone �because of it’s immense size, over ½ of the world’s photosynthesis occurs here �fish, whales, squid ◦ Aphotic Zone �animals feed on sinking dead organisms and have slow metabolic rates �chemosynthetic bacteria can live near thermal vents

• Marine Zones