ENVIRONMENTS AND LIFE

 Limiting factors:    competition
                               predation

Members of an ecologic community

• producers

 
• consumers

 
• scavengers

 
• parasites

Ecologic system = ecologic community + physical environment

Biota: Fauna + flora

Food chain: a single species at each level      Food ______: several species at each level
                                                                                        scavengers &  parasites
 

Diversity: the variety of species that live together within a community

opportunistic species: they are successful invaders when stronger ____________ are limited by perturbances in the physical environment

•   Biogeography studies the distribution and abundance of organisms. Ecology analyzes the factors that determine them.

THE MARINE REALM

Water movements              water currents         Equatorial currents

                                                                          Circumpolar currents

                                                                          Coriolis effect

                                           waves                      breakers

                                           tides                        intertidal zone
                                                                          supratidal zone

Changing conditions => restricted diversity

Marine section

•   continental shelf (shelf break)
•   continental slope conditions
•   continental rise
•   continental breakfast
•   abyssal plain

Marine Life Habits and Food webs

At the base of the marine food web: single celled algae (in the shallows)

                     _____plankton (producers)

                                nekton
 

benthonic (benthic or benthos)
 
 

Comparison of life             on the continental shelf (photic zone)

                                           pelagic environment

                                           ocean floor
 

Physical factors limiting diversity

 Temperature:             calcareous nannoplankton & corals: ___________
                                    diatoms: ________

 Salinity:  brackish or hypersaline waters => less diverse

FRESHWATER ENVIRONMENT

 Low diversity in rivers (low salinity)
 Producers: bottom dwelling org.
 Consumers: insects (larvae)
 Fossils: fish, mollusks

THE ATMOSPHERE

 Oxygen: photosynthesis

 Carbon dioxide: respiration, burning

 Oxygen and nitrogen recycled biologically
 

TERRESTRIAL REALM

 Steeper gradient between poles and equator
 Climatic variation with latitude

Changes with increasing latitudes...

•  Equatorial latitudes: rainforests with _____________ biota

 
•  Tropical latitudes: deserts (atmospheric circulation). ________ diversity

 
•  With + moisture: grasslands & savannahs. ____________ herbivores/carnivores

 
•  Woodlands (more moisture available). Diverse.

 
•  Temperate forest: warmer climates, ___________ trees, diverse fauna.

 
•  Evergreen forests: ______ climate, _______ summers, more rain. Conifers

 
•  Subarctic regions: tundra. Herbivores/carnivores; low trees, mosses, lichens

 
•  Polar regions: very _____ diversity

High mountains  show vertical zonation with altitude
 

Rain shadow deserts - Origin?
 
 
 
 
 

Oceans or large lakes have a stabilizing effect on coastal climates.

Fossil plants or animals => great environmental indicators (Know examples).