2. Understanding Wetland Niches Determining Niches of Plant Species in Saline Wetlands

3. 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 Challenges of Living in a Salt Marsh 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

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

5. 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.

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

7. 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:

8. Cape May Warbler Bay-breasted Warbler Blackburnian Warbler “Myrtle” Warbler 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.

9. 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. examples:

10. Ocean High Tide Low Tide Balanus barnacles Chthamalus barnacles FundamentalNiches Realized Niches

11. Niche Overlap A.Definition - locations where two or more species are present 1. How can two or more species occupy the same realized niche? Specialists vs. Generalists Niche Breadth

12. The Effect of Matt Goo, 2007

13. Realized Niches of Salt Marsh Plants (Generalized)