1. Wetland Plant Population Study- Understanding Niches
Determining Niches of Plant Species in Saline Wetlands

2. Challenges of Living in a Salt Marsh
A. Defining Abiotic Characteristics of Salt Marshes
1. Hydrology - saturated by water for at least all or part of the year
2. Soil - mostly waterlogged clay soils 3. Salinity - organisms must cope with salt
B. Wetland Plant Adaptations
1. Plants - adapted to grow saturated by water
hollow passages from leaves to roots for air movement
oxidation of the surrounding soil
reversing osmotic flow by salt concentration
excretion of salt by glands on leaves and stems

3. What happens when organisms rely on the same resources?
competition = interactions between organisms using the same resources - often in short supply

4. Principle of Competitive Exclusion
If two species are in competition for the same limited resource, one will be eliminated in situations where they occur together.

5. © 2004 Brooks/Cole – Thomson Learning
Principle of Competitive Exclusion
Number of individuals
Species 1
Species 2
Region of
niche overlap
Resource use
Number of individuals
Species 1
Species 2
Resource use

6. How can similar species coexist in natural communities?
ecological niche = role played by an organism the way it makes its living
(niche = “occupation” habitat = “home”)
resource partitioning = coexisting species use slightly different portions of an available resource.
examples:

7. Black-throated green Warbler
The colored areas indicate the feeding zones of these five species of N. American Warblers. The partitioning of resources allows all species to feed off the same tree.
Cape May Warbler
Bay-breasted Warbler
Blackburnian Warbler
“Myrtle” Warbler
Black-throated green Warbler

8. Realized Niche = portion of the fundamental niche actually utilized.
Fundamental Niche = niche occupied by an organism in absence of competition.
Realized Niche = portion of the fundamental niche actually utilized.
Smaller organisms are typically able to exploit more niches.

9. High Tide
Chthamalus barnacles
Fundamental Niches
Realized Niches
Ocean
Balanus barnacles
Low Tide

10. Matt Goo, 2007
The Effect of

12. Realized Niches of Salt Marsh Plants (Generalized)