Introduction: What Is Ecology

1
Introduction What Is Ecology ?

• Chapter 1

2
The future of life on the planet depends on our
understanding of the relationships between the
living (biotic) and non living (abiotic) things
on the planet. Consider the impact of human
activity on the Atmospheric CO2 concentration.
3
Fig. 1.1a
4
wikipedia
5
Outline

• Overview of Ecology
• Ecology of Forest Birds
• Forest Nutrient Budgets
• Vegetation Change Pollen Records
• Nature and Scope of Ecology

6
Overview of Ecology

• Ecology Study of relationships between organisms
  and the environment.
• Simple definition does not convey the extreme
  breadth of this discipline.
• Ecosystem Includes all organisms living in an
  area, and the physical environment with which
  these organisms interact.
• Biosphere Highest level of ecological
  organization.

7
The study of ecology within an evolutionary
context.
8
Hierarchy
9
Individuals
Physiological Ecology
10
Individuals
How is photosynthesis altered by chemicals in
the soil?
11
Individuals
Behavioral Ecology
12
Population Ecology
13
Population
Group of individuals of the same species
occupying a given area.
14
What is a species?
Ernst Mayr defined a species as follows
"species are groups of interbreeding natural
populations that are reproductively isolated from
other such groups."
15
The ecological species concept A species is a
set of organisms adapted to a particular set of
resources, called a niche, in the environment.
16
The ecological role of an organism in a community
especially in regard to food consumption.
Merriam-Webster Dictionary
17
Interactions
18
Community
Groups of interacting species
19
Ecosystem
The ecological community with the physical
factors influencing the community.
20
Landscape Ecology
Landscape ecology represents an unique field
because it looks at the effect of spatial pattern
on ecological processes.
From The Encyclopedia of the Earth
21
Region
The study of ecological structure and process at
influenced by long-term, large scale processes
(i.e., geologic)
22
Ecology of Forest Birds

• MacArthur studied ecology of five species of
  warblers in spruce forests in N.A.
• Theory predicted two species with identical
  ecological requirements could not coexist
  indefinitely.
• Studies found warblers coexisted by feeding in
  different zones of the same tree.

23
Warblers are insect eaters. MacArthur predicted
might coexist and so not compete, and be able to
live in different zones on the same tree. The
prediction was correct. The five warbler species
fed in different zones of the tree.
24
Warbler Feeding Zones
25
Morse (1980) studied the potential of warblers
using different feeding zones in the presence or
absence of other warbler species.
26
(No Transcript)
27
Nutrient Budgets An inventory of the
distribution of nutrients within an
ecosystem Example Nitrogen
28
Forest Nutrient Budgets

• Due to heavy rainfall, many rainforest soils are
  nutrient-poor.
• Nutrient stores in rainforest canopies are
  associated with epiphytes.
• Epiphyte mats contain significant quantities of
  nutrients.
• Trees send roots up to epiphyte mats to access
  nutrients.

29
Forest Nutrient Budgets

• Likens and Bormann estimated 90 of nutrients in
  a New Hampshire forest were locked up in soil
  organic matter.
• Approximately 9.5 was tied up in vegetation.
• Streamflow output amounted to lt 1.

30
Vegetation Change Pollen Records

• Many environmental changes occur over large
  spatial or temporal scales.
• Davis monitored plant pollen deposited in lake
  sediments in the Appalachian Mtns.
• Documented large temporal changes to nearby plant
  communities.

31
Vegetation Change Pollen Records

• Milne modeled transitions between ecosystems
  (ecotones) as phase transitions.
• Searched for edges between critical densities of
  vegetation along ecotones.
• Suggested areas of gradual change within a
  landscape are most likely to contain biological
  responses to environmental changes.

32
Vegetation History from Pollen Sediments
33
Nature and Scope of Ecology

• Ecology Study of relationships between organisms
  and the environment.
• Wide variety of approaches.
• Large temporal and spatial scales.
• Field
• Lab
• Observational
• Manipulative

34
Review

• Overview of Ecology
• Ecology of Forest Birds
• Forest Nutrient Budgets
• Vegetation Change Pollen Records
• Nature and Scope of Ecology

35
(No Transcript)
36
Un Fig. 1.1