ESRM 100 ADMIN

1
ESRM 100 ADMIN

• Holiday Monday Jan 18 (Martin Luther King Day)
• http//www.depts.washington.edu/mlkjr
• Project Topic due by Wed Jan 20
• envir110_at_u.washington.edu
• Also sign-up for field trips by Wed Jan 20.

2
Ecosystems
2
3
Ecosystems

• Species Interaction
• Habitat and Ecological Niche
• Succession
• Community Properties and Structure
• Restoration

3
4

• Organism (species)
• Population
• Biological
• Community
• Ecosystem
• Biosphere (ecosphere)

5
SPECIES INTERACTION

• Predation - antagonistic
• Any organism that feeds directly on another
  living organism is termed a predator.
• Predation influences
• All stages of predator and prey life cycles.
• Specialized food-obtaining mechanisms.
• Other specific predator-prey adaptations.
• Predation can exert selective pressures.
• Co-evolution

5
6
SPECIES INTERACTION

• Competition - antagonistic
• Intraspecific - Competition among members of the
  same species. They cope by
• Dispersal, eg seeds by wind, water, animals
• Territoriality, eg defended to minimize
  competition
• Resource Partitioning, eg young vs adult may use
  different resources (ecological niches)
• Interspecific - Competition between members of
  different species. Best suited will have
  advantage.

6
7
SPECIES INTERACTION

• Symbiosis - Intimate living together of members
  of two or more species (can be
  non-antagonistic).
• Commensalism - One member benefits while other is
  neither benefited nor harmed.
• Cattle and Cattle Egrets
• Mutualism - Both members benefit.
• Lichens (Fungus and cyanobacterium)
• Parasitism - One member benefits at the expense
  of other.
• Humans and Tapeworms

7
8
Defensive Mechanisms

• Avoidance camouflage
• Batesian Mimicry - Harmless species evolve
  characteristics that mimic unpalatable or
  poisonous species.
• Mullerian Mimicry - Two unpalatable or dangerous
  species evolve to look alike.

8
9
Examples of mimicry
http//www.museums.org.za/bio/insects/insect_mimic
ry.htm
9
10
Keystone Species

• Keystone Species - A species or group of species
  whose impact on its community or ecosystem is
  much larger and more influential than would be
  expected from mere abundance.
• eg, Top Predators
• Often, many species are intricately
  interconnected so that it is difficult to tell
  which is the essential component. Perhaps
  keystone set.
• Multiple Key Players

10
11
Keystone species species that play essential
community roles not just from abundance
(examples mycorrhizas, salmon?)
11
12
Community-level Interactions
Keystone species???
(Botkin Keller)
12
13
Habitat and Ecological Niche

• Habitat Place or set of environmental
  conditions in which a particular organism
  lives. Eg, a species address such as
  desert, grassland, log, aquatic, etc
• Ecological Niche functional role and position
  of a species in its ecosystem, Eg, a species
  occupation
• Eg, what resources it uses, how and when it uses
  the resources, and how it interacts with other
  species such as producer, predator, nocturnal,
  etc

13
14
Habitat and Ecological Niche

• Generalists eg, broad niche - live in many
  places, eat a variety of foods, and tolerate a
  wide range of environmental conditions
• Specialists - Narrow niche, less resilient, eg,
  live in one type of habitat, use few foods, or
  tolerate narrow range of environmental conditions

Coyote, raccoon, cockroach
Panda, koala
14
15
Resource Partitioning
Law of competitive exclusion no two
populations of different species will occupy the
same niche and compete for exactly the same
resources in the same habitat for very long So
they migrate, or adapt to partition the
resources, or die!
15
16
Ecological Niche

• Resource Partitioning - Alter physiology or
  behavior to minimize competition.
• Physiology
• Behavior - allows several species to utilize
  different parts of the same resource.

Eg, Panda is a specialist found just around
bamboo forest - significant changes from a
omnivorous bear form to a specialized herbivorous
form
Eg, Warblers, and lizards frogs
16
17
Ecological Niche

• Resourceseparation for wood warblers
• spatially, or
• temporally

17
18
Ecological Niche Weedy Species

• Opportunistic Species - Quickly appear when
  opportunities arise.
• Many weeds are generalists produce many
  offspring.
• Pioneer Species - Can quickly colonize open,
  disturbed, or bare ground. Fast growers.

18
19
COMMUNITIES IN TRANSITION

• Ecological Succession
• Primary Succession - A community begins to
  develop on a site previously unoccupied by living
  organisms.
• Pioneer Species
• Secondary Succession - An existing community is
  disrupted and a new one subsequently develops at
  the site.
• Ecological Development

19
20
Primary Succession development of a community
in an area previously unoccupied
20
(vs disturbed community, then secondary
succession)
21
Mature forest
Lichens (fungialgae)
21
22
Ecological Succession

• Climax Community - Community that develops and
  seemingly resists further change under a given
  climate.
• Clements relay of plant species
• Individualistic Community - Species become
  established according to their ability to
  colonize and reproduce in a given area.
• Gleason

22
23

• Lodgepole Pine
• Once thought of as climax
• Now considered fire adapted

23
24
COMMUNITY PROPERTIES

• Primary Productivity - Rate of biomass
  production. Used as an indication of the rate of
  solar energy conversion to chemical energy.
• Net Primary Productivity - Energy (amount of
  biomass) left after respiration.

24
25
Abundance and Diversity

• Abundance -Total number of individuals of a
  species in an area.
• Diversity - Number of different species, or
  ecological niches, or genetic variation in an
  area.
• Abundance of a particular species often inversely
  related to community diversity.
• As general rule, diversity decreases and
  abundance within species increases when moving
  from the equator to the poles.

25
26
Community StructureDistribution of members of a
population in a given space can be
Random - individuals live wherever resources
are available
Ordered - often theresult of biological
competition
Clustered - individuals of a species cluster
together for protection, mutual assistance,
reproduction, or to gain access to a particular
environmental resource
26
27
Community StructureEdges and Boundaries

• Ecotones - Boundaries between adjacent
  communities.
• Edge Effects - Important aspect of community
  structure is the boundary between one habitat and
  others.
• May extend for 100s of meters
• May produce differently-shaped habitat patches.

27
28
Edges and Boundaries

• Ecotones- the boundaries between adjacent
  habitats
• Often rich in species diversity
• Exampleboundary between a forest and a meadow

28
29
Shapes of Preserves can be important!
29
30
Restoration Ecology Returning damaged, degraded,
or destroyed ecosystems to some set of conditions
considered functional, sustainable, and natural.
31
Current Environmental Conditions

• Half the world's wetlands were lost in the last
  100 years.
• Land conversion and logging have shrunk the
  world's forests by as much as 50.
• Nearly three-quarters of the world's major marine
  fish stocks are over fished or are being
  harvested beyond a sustainable rate.
• Soil degradation has affected two-thirds of the
  world's agricultural lands in the last 50 years.

31
32
Introduced Species

• If introduced species prey upon, or compete more
  successfully than, native species, the nature of
  the community may be altered.
• Human history littered with examples of
  introducing exotic species to solve problems
  caused by previous introductions.
• Mongoose and Rats in Caribbean and Hawaii

32
33
Introduced Species and Community Change
33
34
What's Happening to the Frogs?
In some places, up to sixty-percent of frogs and
salamanders have abnormal limbs, digits, eyes, or
internal organs.
Environmental science allows us to explore the
possible causes of such problems. (observational
/or experimental)
34
35
Applied Science
Many environmental scientists want to use their
knowledge to repair ecological systems that have
been damaged by humans.
35
36
Restoration Ecology
Restoration - the re-creation of species
composition and ecosystem functions in areas
disrupted by human actions
The Kissimmee River - the focus of an ambitious
8 billion restoration project.
36
37
Restoration Tools

• Labor-intensive horticultural or animal control
  methods
• Removal of exotic species

37
38

• Restoration Issues
• Impact of natural disturbance (fires, hurricanes,
  etc.)
• Multiple historic states
• Climate changes and evolution
• How do we distinguish between desirable and
  undesirable change?

38
39

• Artificial Ecosystems
• Example human-designed wetlands can be used to
  treat sewage effluent

39
40
Key Points

• An ecological niche is the functional role and
  position of a species in its ecosystem
• Specialist or generalist
• Resource partitioning populations can share
  environmental resources through specialization
  and reduce direct competition
• Weedy species can be opportunistic or pioneering
  
• Species interactions may occur through predation,
  competition (intra- interspecific), or
  symbiosis (mutualism, commensalism, or
  parasitism).

40
41
Key Points

• Organisms may mimic or avoid each other as a
  defensive mechanism.
• Keystone species are very important to a
  community.
• Restoration Ecology - returning damaged,
  degraded, or destroyed ecosystems to some set of
  conditions considered functional, sustainable,
  and natural.
• Communities often have repeatable structures and
  properties that exhibit parallel chronosequences
  following disturbances (primary and secondary
  succession).
• Introduced species may change the native
  community.

41