Synecology of Beach Vegetation Along the Pacific Coast of the United States of America: A First Approximation

Subtropical Convergence Environments

“…The lower wet slack habitat is generally inundated during the winter and is dominated by Androtrichum trigynum and other inundation-tolerant species (Phyla canensis, Bacopa monnieri, Pluchea sagittalis, Paspalum vaginatum, Hydrocotyle bonariensis) and marsh remnants Uuncus acutus, Typha domingensis; Cordazzo andSeeliger 1987, 1993). As has been observed elsewhere (Barbour et al 1976(Barbour et al , 1987Godfrey 1977;Wiedemann 1984;Fahrig et al 1993), shore disturbance gradients, either acting alone or in concert with the dominant plant cover, are likely to have influenced the genesis of different fore dune physiographies along the southern Brazilian coast over time (Costa et al 1991;Seeliger 1992b;Cordazzo and Seeliger 1993; Fig. Slacks and adjacent marshes serve as nesting sites for several shore birds and are inhabited by the skunk Conepathus chinga, the armadillo Dasypus hybridus, and the fox Dusicyon gymnocercus (Gianuca, Sect.…”

“…Gradients of beach/ foredune sediment transport and edaphic stability of foredunes not only induce different site-specific environmental conditions (Hesp 1991), but also influence the composition of vegetation and the abundance of species (Barbour 1992;Fahrig et al 1993). Pioneer backshore and foredune plants are selected in accordance with their physiological tolerance and morphological and reproductive traits (Barbour et al 1976(Barbour et al , 1987Hesp 1991). The environmental conditions and plant associations define six typical habitats on southern Brazilian backshores and foredunes.…”

“…Since tidemarks are wind-controlled, they are unstable and often overlap, thus leading frequently to life-cycle disruptions of the otherwise common annual driftline species Cakile maritima, Calycera crassiflora, and Calystegia soldanella (Barbour et al 1976;Doing 1985;Moreno-Casasola and Espejel1986;Fahrig et al 1993). As a consequence, southern Brazilian beaches lack driftline habitats because species retreat to more stable and permanent tidemarks behind the backshore (Cordazzo and Seeliger 1993).…”

Responses of Uniola paniculata L. (Poaceae), an Essential Dune-Building Grass, to Complex Changing Environmental Gradients on the Coastal Dunes

“…This contrasts with patterns in more saline habitats such as salt marshes and saline desert dunes where plant size is often negatively correlated with soil salinity (Lubke 1983;Haines and Dunn 1985;Donovan et al 1997;Griffiths 2006). The pattern in coastal dunes may differ from these other habitats because coastal dune soil salinity rarely approaches toxic levels (Barbour et al 1976), and other factors such as responses to sand burial may be more important in controlling species-specific responses (Houle 2002). Further, there may be tradeoffs in plant responses to abiotic factors, as found for the perennial dune grass Leymus mollis: nearshore ramets had a higher relative growth rate allowing plants to withstand sand deposition, but at the expense of lowered salt tolerance (Houle 2002).…”

Coastal Mycology and Invasive Species: Boundary Conditions for Arbuscular Mycorrhizal (AM) Fungi in Incipient Sand Dunes

“…For example, Barbour et al (1976) found that along the leading edge of vegetation of 34 beaches on the Pacific Coast in the USA, the concentration of soluble salt at a depth of 10 cm, was 0.008-0.280%.…”