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Factors Restricting Recruitment Of Ascophyllum Nodosum L (Le Jolis), Paula K B Philbrick

Doctoral Dissertations

Ascophyllum nodosum dominates a wide zone on the shore. Juveniles occur high in the zone where canopy is continuous and grazing animals few. Settlement could account for the restricted range if it were enhanced under canopy or on the upper shore. Settlement was monitored under canopy and in the open at four shore levels during spring 1983. Propagules settled everywhere. Settlement does not restrict plant establishment. Germlings caged and not caged were placed under canopy and in the open through the zone to evaluate the effects of animals and the physical environment (shore level x frond cover) on survival and …

A Study Of Basidiomycetes Isolated From Coarse Woody Debris And Contiguous Soil Horizons In A Mixed Deciduous-Conifer Forest In New Hampshire, United States Of America, Therese Ann Thompson

Doctoral Dissertations

The wood decay fungus Hypholoma sublateritium (Fr.) Quel., links the mineral (BC & E) and organic (Oe) soil layers to decomposing coarse woody debris (CWD) in a northern hardwood forest. This link supports the possibility that energy stored in woody debris can facilitate the vertical transfer of elements and compounds within the soil profile. This potential transfer implies new pathways for biogeochemical cycling within forests. H. sublateritium was isolated from basidiocarp fruiting bodies (October 1997 & 1998), Acer rubrum L. bole wood (June 1999), and three soil horizons (October 1999 and October 2000) from one of six research sites in …

An Investigation Of Genetic Variation Within Northwest Atlantic Porphyra (Bangiales, Rhodophyta) With Specific Phylogeographic Analysis Of The Common, Rocky Intertidal Species, Porphyra Umbilicalis, Brian William Teasdale

Doctoral Dissertations

To investigate the phylogeography of the rocky intertidal red alga, Porphyra umbilicalis Kutzing, a restriction fragment polymorphism assay (RFLP) of the ribulose bisphosphate carboxylase large subunit ( rbcL) was developed to accurately distinguish P. umbilicalis from the other morphologically similar species in the North Atlantic. Initial screening of ∼800 Porphyra specimens resulted in the additional discovery of a cryptic Porphyra taxon.

The presence and variability of group-I introns of the ribosomal small subunit (SSU) were screened in North Atlantic species of Porphyra in order to assess whether they could be biogeographically informative. In an initial screening for the helix 50 …