10/5/2015 chapter 14 ecosystem organization and energy flow
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CHAPTER 14CHAPTER 14
ECOSYSTEM ORGANIZATION AND ENERGY FLOWECOSYSTEM ORGANIZATION AND ENERGY FLOW
ECOLOGY AND ECOLOGY AND ENVIRONMENTENVIRONMENT
EcologyEcology – the branch of biology that – the branch of biology that studies the relationships between studies the relationships between organisms and the environmentorganisms and the environment
The The environmentenvironment is anything that is anything that affects an organism during its affects an organism during its lifetimelifetime
Organisms are affected by both Organisms are affected by both bioticbiotic (living) and (living) and abioticabiotic (nonliving) (nonliving) factors of the environmentfactors of the environment
ORGANIZATION OF ORGANIZATION OF ECOLOGICAL SYSTEMSECOLOGICAL SYSTEMS
Ecologists study ecological relationships Ecologists study ecological relationships at different levels of organization:at different levels of organization:
OrganismOrganism – smallest, independent living – smallest, independent living unitunit
Ex: one leopard frogEx: one leopard frog PopulationPopulation - members of the same species - members of the same species
living in a particular arealiving in a particular area Ex: leopard frogs in a pondEx: leopard frogs in a pond
CommunityCommunity - populations of different - populations of different species living in the same areaspecies living in the same area
Ex: pond community (frogs, fish, plants, etc.) Ex: pond community (frogs, fish, plants, etc.)
ECOLOGICAL SYSTEMSECOLOGICAL SYSTEMS An An ecosystemecosystem - all interacting - all interacting
organisms in an area and how they organisms in an area and how they interact with their abiotic surroundings.interact with their abiotic surroundings.
Living things can be organized into Living things can be organized into energy relationships.energy relationships.
ProducersProducers – trap sunlight, carry out – trap sunlight, carry out photosynthesisphotosynthesis
ConsumersConsumers – feed on producers – feed on producers Trophic levelsTrophic levels – describe how energy – describe how energy
flows through an ecosystemflows through an ecosystem Producers occupy the first trophic levelProducers occupy the first trophic level Arranged like a pyramidArranged like a pyramid
ECOLOGICAL SYSTEMSECOLOGICAL SYSTEMS
Consumers can be divided into:Consumers can be divided into: primary consumersprimary consumers secondary consumers secondary consumers
Primary consumers feed directly on plants Primary consumers feed directly on plants are known as are known as herbivoresherbivores (mouse) (mouse)
Second trophic levelSecond trophic level Secondary consumers feed on other Secondary consumers feed on other
animals and are called animals and are called carnivorescarnivores (snake)(snake)
Third trophic levelThird trophic level Animals that feed on carnivores are Animals that feed on carnivores are
fourth trophic level consumers (hawk)fourth trophic level consumers (hawk)
TROPHIC LEVELSTROPHIC LEVELS
ECOLOGICAL SYSTEMSECOLOGICAL SYSTEMS Omnivores – feed on both plants and Omnivores – feed on both plants and
animalsanimals Can occupy different trophic levelsCan occupy different trophic levels
Decomposers – feed on dead Decomposers – feed on dead organisms as their source of energyorganisms as their source of energy
Includes bacteria and fungiIncludes bacteria and fungi Convert organic matter into inorganic Convert organic matter into inorganic
matter that can be used by producersmatter that can be used by producers
COMMUNITY COMMUNITY INTERACTIONSINTERACTIONS
All consumers depend on All consumers depend on producers for their energy (directly producers for their energy (directly or indirectly).or indirectly).
One way to study interactions One way to study interactions among communities involves among communities involves analysis of the various analysis of the various food chainsfood chains..
Show linear feeding patternsShow linear feeding patterns Organisms can be involved in Organisms can be involved in
several food chains at the same several food chains at the same time forming a time forming a food webfood web. .
Show complex feeding patternsShow complex feeding patterns
COMMUNITY COMMUNITY INTERACTIONSINTERACTIONS
Changes in the population size of Changes in the population size of one species can influence one species can influence population sizes of other species.population sizes of other species.
Insecticide use may decrease the Insecticide use may decrease the population size of organisms that feed population size of organisms that feed on insects. on insects.
Population sizes may change due Population sizes may change due both biotic and abiotic factorsboth biotic and abiotic factors
WORLD BIOMESWORLD BIOMES
TEMPERATE DECIDUOUSTEMPERATE DECIDUOUS Found in areas with Found in areas with
moderate rainfall (75-moderate rainfall (75-130 cm per year)130 cm per year)
Long summers (130-Long summers (130-160 days)160 days)
Colonized by many Colonized by many large deciduous trees large deciduous trees
Typical animals include:Typical animals include: leaf eating animals, leaf eating animals,
insectsinsects Birds, skunks, deerBirds, skunks, deer mosquitoes , etc. mosquitoes , etc.
GRASSLANDGRASSLAND Also known as a prairieAlso known as a prairie Average rainfall amount Average rainfall amount
is 30-85 cm per yearis 30-85 cm per year Not adequate to support Not adequate to support
the growth of treesthe growth of trees Mostly grasses and Mostly grasses and
wildflowerswildflowers Good for agricultural crops Good for agricultural crops
(corn, wheat)(corn, wheat) Experience long periods Experience long periods
of droughtof drought Common animals Common animals
include:include: Grazing mammalsGrazing mammals Small insectsSmall insects RodentsRodents CarnivoresCarnivores
SAVANNASAVANNA Similar to a prairieSimilar to a prairie Receive about 100 cm Receive about 100 cm
of rainfall per yearof rainfall per year Home to many grazing Home to many grazing
animalsanimals Have a dry season and Have a dry season and
a rainy seasona rainy season During the rainy During the rainy
season, trees produce season, trees produce leaves and the grass leaves and the grass grows rapidlygrows rapidly
In the African In the African savanna, migration is savanna, migration is typical.typical.
DESERTDESERT Very dry areas found Very dry areas found
all over the world all over the world Receive less than 25 Receive less than 25
cm of rainfall per yearcm of rainfall per year Plants are adapted for Plants are adapted for
conserving waterconserving water Scattered, thorny Scattered, thorny
plantsplants Many animals can live Many animals can live
here, most are here, most are nocturnalnocturnal
BOREAL CONIFEROUS BOREAL CONIFEROUS FORESTFOREST
Include the evergreen Include the evergreen areasareas
Annual rainfall of 40-Annual rainfall of 40-100 cm per year100 cm per year
Growing season is less Growing season is less than 102 daysthan 102 days
Trees must withstand Trees must withstand long cold winterslong cold winters
Animals include mice, Animals include mice, bears, wolves, moose, bears, wolves, moose, and fliesand flies
TUNDRATUNDRA Long, severe winters and short summers of less Long, severe winters and short summers of less
than 100 daysthan 100 days Little rainfall (10-25 cm per year)Little rainfall (10-25 cm per year) Deep layers of soil are permanently frozen Deep layers of soil are permanently frozen
(permafrost)(permafrost) Supports very few forms of animals and plants.Supports very few forms of animals and plants. No trees can live in this biome.No trees can live in this biome.
TEMPERATE TEMPERATE RAINFORESTRAINFOREST
Receive about 200 cm of rain per Receive about 200 cm of rain per yearyear
Found in fertile and mild Found in fertile and mild temperatures with lush plant temperatures with lush plant growth.growth.
Undisturbed areas have 800-year-Undisturbed areas have 800-year-old trees nearly 100 meters tallold trees nearly 100 meters tall
Many are covered with mosses Many are covered with mosses and fernsand ferns
Over 90% of the original Over 90% of the original temperate rainforests have temperate rainforests have already been logged.already been logged.
Found near coastal areas of Found near coastal areas of Pacific northwestPacific northwest
Northern California, Northern California, Oregon, Washington, Oregon, Washington, Canada, AlaskaCanada, Alaska
TROPICAL RAINFORESTTROPICAL RAINFOREST Found primarily in the Found primarily in the
equatorial regions.equatorial regions. Considered the richest Considered the richest
biomebiome Warm temperatures Warm temperatures
year round, and rain year round, and rain falls almost daily (200-falls almost daily (200-1000 cm a year)1000 cm a year)
Thousands of species of Thousands of species of plants in very small plants in very small areasareas
Many species of animals Many species of animals
SUCCESSIONSUCCESSION Communities are relatively stable Communities are relatively stable
when left undisturbedwhen left undisturbed Known as climax communities Known as climax communities
Succession is the process of changing Succession is the process of changing from one type of community to another from one type of community to another
Two types:Two types: Primary succession - occurs in areas where Primary succession - occurs in areas where
plants and animals didn’t exist before plants and animals didn’t exist before (volcanic areas)(volcanic areas)
Secondary succession – occurs when a Secondary succession – occurs when a community is disturbed by natural or human community is disturbed by natural or human action, and it returns to a previous stage in action, and it returns to a previous stage in the succession (forest fires, clear cutting)the succession (forest fires, clear cutting)
PRIMARY SUCCESSION
SECONDARY SUCCESSION
CHAPTER 14CHAPTER 14
ECOSYSTEM ORGANIZATION AND ENERGY FLOWECOSYSTEM ORGANIZATION AND ENERGY FLOW
KINDS OF INTERACTIONSKINDS OF INTERACTIONS
PredationPredation – a predator captures prey, – a predator captures prey, kills it, and eats it.kills it, and eats it.
Elimates poorly adapted individualsElimates poorly adapted individuals ParasitismParasitism – the host is harmed and – the host is harmed and
the parasite benefitsthe parasite benefits Parasites can live inside or outside the Parasites can live inside or outside the
host. host. Mistletoe, tapeworms, fleasMistletoe, tapeworms, fleas
VectorsVectors are organisms that can spread are organisms that can spread parasites.parasites.
Mosquitoes, ticksMosquitoes, ticks
KINDS OF KINDS OF INTERACTIONS INTERACTIONS
CommensalismCommensalism – one organism benefits and the – one organism benefits and the other is not affected. other is not affected.
Remoras and sharksRemoras and sharks Tree mossesTree mosses
MutualismMutualism – both organisms benefit from one – both organisms benefit from one anotheranother
E.coliE.coli and humans and humans Bees and flowering plantsBees and flowering plants
CompetitionCompetition – an interaction between organisms in – an interaction between organisms in which both organisms are harmed to some extent.which both organisms are harmed to some extent.
Weeds and garden plantsWeeds and garden plants Occupying different niches helps reduce Occupying different niches helps reduce
competitioncompetition
PRIMARY SUCCESSION
SECONDARY SUCCESSION