Transcript ecology - Auburn School District

ECOLOGY
•Study of interactions between
living organisms (biotic) & their
environment (abiotic)
p1145
Important terms to know
• Biosphere – entire part of the earth where
•
•
•
•
living things exist.
Ecosystem – interaction of living and nonliving in a particular area
Community - group fo organism interacting in
same area
Population – group of individuals within a
community of the same species
Niche – an individual organism’s “way of life”
position or function in a community
Biome
large regions in biosphere classified
on the basis of plant life (Flora) &
climates (latitude & rain ppt)
Figure 52.9 The distribution of major terrestrial biomes p1151
Figure 52.12 Tropical forests
Figure 52.12 Deserts
Figure 52.12 Savanna
Figure 52.12 Savanna
Figure 52.12 Chaparral
Figure 52.12 Chaparral
Figure 52.12 Temperate grassland
Figure 52.12 Coniferous forests (Northern)
Figure 25.12 Temperate Broadleaf forest (deciduous)
Figure 52.12 Tundra
Figure 52.15 The distribution of major aquatic biomes p1158
Figure 52.16 Freshwater biomes: Oligotrophic lake (left), eutrophic lake (top right),
stream flowing into a river (bottom right) p1159
Wetland
52.16
Figure 52.16 Streams and rivers
Damming the Columbia River Basin
Estuary
52.16 p 1160
Figure 52.16 Examples of marine biomes
Intertidal Zones
Oceanic Pelagic Zone
Coral Reef
Marine Benthic Zone
Black smoker
Ecosystem
Interaction of Abiotic & Biotic Factors
Abiotic Factors
• Temperature
• Water and Oxygen
• Salinity
• Sunlight
• Altitude
• Sunlight
• Rocks and soil
• Carbon Dioxide
Biotic Factors
Living species, as
Predator / Prey
Parasite / Host
Competition
• Interspecific competition (–/– interaction) occurs
when species compete for a resource in short supply
–
Examples: Weeds growing in garden; Lynx & foxes compete
for same prey (hares)
• The competitive exclusion principle states that two
species competing for the same limiting resources
cannot coexist in the same place
–
Examples: ???
Ecological Niche
•
•
An organism’s address ; profession ; job in a
community
Example p 1196 (2 barnacle species)
1.
Fundamental Niche
•
2.
Area used under ideal circumstances
Realized Niche
•
Area an organism actually lives within
Keystone species
• Examples:
– Seastar
– Sea otter
(p1204-1205)
Keystone Predator = Species that makes a large impact on a community
Other examples: elephant, beavers, and the seastar as below…
Sea otters as keystone predators in the North Pacific
What
happened?
What is the
cause?
Figure 54.21
(a) Soon after fire
(b) One year after fire
Large-scale disturbance: Mount St. Helens
• Primary Productivity = Amt. of light
energy converted to chemical energy
by autotrophs of an ecosystem during
a given period of time period.
P1220 fig55.4
Decomposers
Fungi decomposing a log --- Decomposers essential for cycling of Carbon,etc
Primary production of different ecosystems
Primary Productivity = Amt. of light energy converted to chemical energy by
autotrophs of an ecosystem during a given period of time period.
Regional annual net primary production for Earth
Biotic Factors (Food Chain)
• Autotrophs (producers)
• Heterotrophs (consumers)
– Herbivores
– Carnivores
– Omnivores
Primary
Secondary
Tertiary Consumers
• Decomposers
– Note difference from Scavengers
• Food Chain; Food Web; Energy Pyramid
54.13 p1202
--- Food chain and trophic levels
P1203 Food WEB (Transfer of energy in a community = many chains)
Figure 54.11 An idealized pyramid of net production p1226
Figure 55.10
Less than 17%
Of the caterpillar’s food is actually
Used for secondary production
(growth).
Plant material
eaten by caterpillar
200 J
67 J
Feces
100 J
Not assimilated
Cellular
respiration
33 J
Growth (new biomass;
secondary production)
Assimilated
Assimilated
Food energy available to the human population at different trophic levels
Cycles
• Cycling of chemical Elements in an
Ecosystem is essential
• Remember --- Conservation LAWS
– Conservation of Mass
– Conservation of Energy
• Specific Cycles to know:
– Water; Carbon; Nitrogen; Phosphorus
The water cycle p1228
The carbon cycle p1228
The nitrogen cycle p1229
We’ve changed our tune
Biological magnification of DDT in a food chain
Page 1244 --- Changes ion the pH of ppt in New Hampshire
Erosion of Earth’s ozone shield: The ozone hole over the Antarctic
Following slides are features
of species that allow them to
survive and reproduce successfully
which is the foundation for
BIOLOGICAL EVOLUTION.
Predation
• Predation is the eating of live or freshly killed organisms. To do this
predators use a number of techniques and foraging strategies.
• If an organism can procure prey, it reproduces more.
• If prey can avoid predators successfully, then the prey are more
likely to have offspring.
• Predation & Population Dynamics
– Predation may decrease prey number
– Lack of prey or prey species can reduce number of predators
• Predation and Species Diversity
Number & types of species can be affected by predators.
Predators can eliminate species in an area, but can also maintain
species diversity.
Lion with kill in a grassland community
Adaptations for Survival
• Camouflage
• Warning Coloration
• Mimicry
• Variation within a species due to
mutations
• Mutations that are selected for survival
and increased reproduction – adaptation
• Demonstrates the Survival of the Fittest
Camouflage: Poor-will (left), lizard (right)
Warning coloration in a poisonous blue frog
Deceptive coloration: moth with "eyeballs"
Mimicry
Mimicry: Cuckoo bee (left), yellow jacket (right)
Parasitic behavior: A female Nasonia vitripennis laying a clutch of eggs into the pupa
of a blowfly (Phormia regina)
Mutualism between acacia trees and ants
Commensalism between a bird and mammal
Figure 52.12 How well do these populations fit the logistic population growth model?
Figure 52.14 Decreased fecundity at high population densities
Figure 52.15 Decreased survivorship at high population densities
Figure 52.16 Decline in the breeding population of the northern pintail (Anas actua)
from 1955 to 1998
Figure 52.17 Long-term study of the moose (Alces alces) population of Isle Royale,
Michigan
Figure 52.18 Extreme population fluctuations
Figure 52.19 Population cycles in the snowshoe hare and lynx
Figure 52.20 Human population growth
Figure 52.21 Demographic transition in Sweden and Mexico, 1750-1997