Unit 5 Lesson 1 What Is an Ecosystem?...2020/02/05 · Title PowerPoint Presentation Author McDougal Littell Created Date 20200113113826Z

Unit 5 Lesson 1 What Is an Ecosystem?

Copyright © Houghton Mifflin Harcourt Publishing Company


What Is an Ecosystem?


• An organism’s environment is all the living and nonliving thingsthat surround and affect the organism.• Environments include biotic and abiotic parts. Biotic parts are

living things in an environment, such as plants, animals, andother organisms




• Abiotic parts arenonliving things inan environment,such as climate,water, soil, light,air, and nutrients.• Abiotic parts of an

environment havean important role.Temperature andamount of wateraffect whichplants andanimals can live ina place.




Word bank•White ibis birds•Black bears•Water•Moist air•Muddy soil•Black berry bushes•Pitcher plants•Shady areas•Climate•Mosquitoes•Willow trees




• An ecosystem is all the organisms living in a placetogether with their environment. Each ecosystem has itsown living and nonliving things.• An ecosystem can be huge, such as a large forest or

desert, or it can be small, such as a mud puddle or asingle bush.


• A group of organisms of the same species in an ecosystem iscalled a population.• Each ecosystem contains different groups of living things. A

savanna ecosystem may contain populations of zebras as well asgrasses and trees.


Populations and Communities


• The different populations that share an ecosystem makeup a community.

• A community consists of all the populations that live andinteract in an area.




• Populations in every ecosystem need food, water, shelter,and space to live.

• The interaction between populations to meet these needsis called competition.




• Populations that compete andobtain enough resources willsurvive, while those thatcannot compete will notsurvive.• These resources are called

limiting factors, because thereis only enough food, water,shelter, and space to support acertain number of organisms.• Competition also occurs within

populations. Strongerindividuals get the most foodand best shelter. Thus, weakerindividuals may not survive.




• An organism’s habitat is the place where it lives within anecosystem. Several populations share the same habitat.


Find Your Niche


• An organism’s niche is itscomplete role or function inits ecosystem. A nicheincludes all the ways theorganism survives.

• An organism’s niche includeshow it finds food, as well asthe climate in which itthrives.


Find Your Niche


• Every organism has a niche.Having different niches allowsdifferent organisms to survive inthe same habitat.

• Organisms with a specific wayof living have a narrow niche.For example, an animal thateats only one type of foodcannot survive without thatfood.

• Organisms with narrow nichestend to live in specific places,while those with broad nichesoften move around large areas.


Find Your Niche



Find Your Niche


• Populations can share ahabitat but not the sameniche.

• For example, red-shouldered hawks andbarred owls share ahabitat, but have differentniches. They both huntdifferent prey at differenttimes of the day.

• If two populations oforganisms share a niche,they must compete forresources.


Find Your Niche



Find Your Niche


• Diverse means different in kind.Diversity is the variety of differentspecies that live in an ecosystem.

• An ecosystem that is very diversecontains many species.Ecosystems without muchdiversity may be inhabited byonly a few species.

• Organisms are connected in alarge, complex web. The moretypes of organisms in anecosystem, the larger the web,and the more resources available.


Diversity


• Organisms are connected in a large, complex web. The moretypes of organisms in an ecosystem, the larger the web, andthe more resources available.


Diversity

• Climate and location affect the amount andtypes of resources that are available fororganisms.• Generally, very diverse ecosystems, such as

coral reefs and rain forests, are near theequator. Less diverse ecosystems are fartherfrom the equator.



Diversity



• Humans can damage ecosystems and affect diversity byreducing the number of species living in the ecosystem.

• Activities such as overhunting or destroying forests to buildmay lower the numbers of important species.

• Species in those environments have lost their habitats, anddiversity has decreased.

Diversity



Diversity

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Unit 5 Lesson 1 What Is an Ecosystem?...2020/02/05 · Title PowerPoint Presentation Author McDougal Littell Created Date 20200113113826Z