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

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

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

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.

© 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

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:

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

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.

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

Matt Goo, 2007 The Effect of

Realized Niches of Salt Marsh Plants (Generalized)