Ecological SystemsChapter 31

Kelly RichterKelly Richter

Introduction

Ecology- study of living things › Way they interact with physical

environment› Greek words

Oikos meaning house Logic meaning for study

› Important for determining role they play› How to best maintain for future

generations

Ecology

Biotic- living organisms, plants, animals, bacteria, fungi

Abiotic- nonliving factors of environment › Air > Temperature› Water > Altitude› Rocks > Light› Minerals > Soil

Ecologists study interaction ob biotic and abiotic worlds

Habitats

Smallest level of relationship ecologists study

Refers to an organism’s specific requirements:› Food› Water› Shelter› Space

Habitats (continued)

Food requirements vary greatly Basis of how organism derives energy All organisms require water to survive Shelter- way organism protects itself

from environment› Protective body parts or constructing a

shelter Space in which to live lives

› Small to large area depending on organisms

Populations

Group of same organisms living in specific area

Groups of same organisms- species› Group of organisms genetically resemble

each other Can reproduce with each other

Small- population of bacteria on particle of soil

Large- human begins in the United States

Populations (continued)

Specialists- threatened by loss/change in habitat› Requires special habitat requirements

Wolves, elephants, tigers, and others Threatened by loss or change in habitat

Generalists- survive in wide range oh habitats› Humans, squirrels, mice, rats, and many

insects› Can tolerate extreme changes in habitats

Communities

Interaction between different populations in a particular area

Can be called symbiotic relationship› One or more organisms benefit for each

other Mutualism- interaction of two species

› Each benefit from the action of the other Example is the lichen community Algae and a fungus

Communities (continued)

Commensalisms- two organisms› One benefits from, other doesn’t harm host› Remora fish and shark host

Parasitism › One organism harms a host› Takes nutrition for it› Tick on a dog

Ecosystems

Ecosystem- short word for ecological system

Interaction of a community with abiotic factors› Amount of sunlight a region receives› Amount of moisture in an area› Temperature of the environment› Surrounding landscape

Ecosystems (continued)

Largest ecosystem- ecosphere› Relationship between biotic and abiotic

components On entire planet

Two broad categories:› Aquatic ecosystems › Terrestrial ecosystems

Ecological SystemsChapter 31

Kelly RichterKelly Richter