AN INTRODUCTION
TO ECOLOGY AND THE
BIOSPHERE
Ecology What is ecology? Study of interactions between
organisms and their environment. The environment includes both biotic
and abiotic factors. Biotic = living, abiotic = non-living Ecology therefore will incorporate
biotic and abiotic interactions
Four Levels of Inquiry:1. Organismal Ecology:
Ways the individual meets challenges posed by the environment.
What is this area of ecology concerned with?
Behavioral, morphological and physiological developments in the organisms that allow them to interact with their environment.
2. Population Ecology
What is a population? Group of individuals of the same species
living in the same area. What is this area of ecology concerned
with? Factors that affect population size and
composition.
3. Community Ecology
What is a community? All of the organisms that occupy a
particular area. What is this area of ecology concerned
with? Involves predator/prey relationships,
competition and disease.
4. Ecosystem Ecology
What is an ecosystem? Includes all of the biotic and abiotic
factors plus the community that exists in a specific area.
What is this area of ecology concerned with?
Energy flow, chemical cycling, primary productivity.
Abiotic factors of the biosphere:
Biosphere - global ecosystem temperature water sunlight wind rocks and soil periodic disturbances (e.g. tornadoes,
hurricanes…)
Seasonal effects on climate:For example turnover in a lake:
Biomes:
What is a biome? A major community that is classified by
the predominant vegetation and characterized by the adaptations of organisms that live there.
Aquatic Biomes
Vertical stratification is important in aquatic biomes
Zonation in a Lake:
Lake classification:
What is an oligotrophic lake? Deep water and nutrient poor, water is
very clear. What is a eutrophic lake? Shallower water, nutrient rich, murky
water.
Oligotrophic lake
Eutrophic lake
Wetlands
What are wetlands? Area covered with water that supports
aquatic plants. Very rich biome with diverse birds,
invertebrates, mammals, etc.
Wetlands
Estuary
What is an estuary? The area where freshwater merges with
salt water. River nutrients enrich the estuary. Salinity varies throughout the estuary. Important source of oysters, crabs and
fish.
Estuary
Marine Community
Zonation in a marine environment:
Intertidal Zone
Rocky Shores: What challenges are faced by organisms
that live here? Rough waves pounding the rocks Salinity changes Hard rocky substrate
Intertidal Zone
Coral Reef
Where are the producers in this community?
Symbiotic algae live in the coral, and are producers for this community.
Waves bring constant supply of nutrients Water is shallow enough to allow for light
penetration, and photosynthesis.
Coral Reef
Oceanic Pelagic Biome
Temperate oceans have seasonal turnover of nutrients like in lakes
Some tropical areas have stratification and no turnover of nutrients.
Photic zones have phytoplankton as producers.
Large animals move up to photoic zone to feed.
Pelagic Zone
Benthos Ocean bottom of neritic and pelagic
zones Neritic benthic communities are very
productive Deep benthic communities - abyssal
zone - are adapted to cold water, no light, and low nutrient levels.
Deep sea vents found here, producers are chemoautotrophs not photoautotrophs.
Benthos
Terrestrial biomes
REVIEW THE CHARACTERISTICS OF THE DIFFERENT BIOMES
AND IDENTIFY WHICH BIOME IS SEEN IN THE FOLLOWING
SLIDES...
Desert biome
Benthos
Deciduous Forest
Grasslands
Tundra
Desert
Deciduous forest
Tundra
Coniferous forest
Temperate grassland
Savanah
Tropical rain forest
Chaparral
Taiga/Tundra
Wetlands
Where would this creature live?
What adaptations does it have for life here?
Where would these animals be found?
Where would these short flowers be found?
Regulators/Conformers
Cost benefit analysis of homeostasis What is a regulator? Organisms that can survive fluctuations
in the environment through physiological regulations
What is a conformer? Organisms that conform to their
environment.
Principle of Allocation
What is the principle of allocation? Organisms have limited supply of energy
that they can allocate to living. The way they “spend” their energy will
affect what sort of organism they are.
Responses to Envoronmental Variations:
Physiological responses: regulation and homeostasis are
physiological responses acclimation shifts an organisms’
tolerance to the environmental change For example people who attempt to climb
Everest must acclimate to the higher altitude.
Morphological Responses
Responses that change the form or anatomy of the organism.
Mammals grow heavier coats n the cold months
plants are more morphologically plastic than animals.
Behavioral Responses
Instantaneous response that can be easily reversed.
Moving away from unfavorable environment.
Concept Check
1. What is the difference between biotic and abiotic factors?
2. What characterizes the following biomes?
1. Desert2. Tropical rain forest3. Tundra4. Coral reef5. Estuary
3. What are the differences between oligotrophic and eutrophic lakes?
4. What is the difference between a regulator and a conformer?