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Full-Text Articles in Biology
Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost
Changes In Leaf Morphology, Photosynthesis And Nitrogen Content In Two Coastal Shrubs, Elizabeth Kost
Theses and Dissertations
It is important to understand mechanisms that facilitate expansion of two common shrubs, Morella cerifera and Baccharis halimifolia in coastal environments. The purpose of my study was to investigate the physiological and structural changes that occur as leaves age. Photosynthesis, incident light, chlorophyll, and leaf C:N ratios were quantified for young, intermediate, and old leaves (distal, central and proximal leaves, respectively). Leaf structural differences were also compared. Leaves did not change morphologically with age. Light decreased with leaf age and during winter months. Photosynthesis showed no seasonal or age related patterns. Chlorophyll increased initially and then declined with age due …
Spatial And Temporal Patterns Of Anadromous Fish Passage At Boshers Dam Vertical Slot Fishway On The James River, Richmond, Virginia, Matthew Thomas Fisher
Spatial And Temporal Patterns Of Anadromous Fish Passage At Boshers Dam Vertical Slot Fishway On The James River, Richmond, Virginia, Matthew Thomas Fisher
Theses and Dissertations
Boshers dam vertical slot fishway, James River, Virginia, U.S.A., opened in 1999 and restored connectivity to 543.3 km of spawning habitat for anadromous fish. The fishway also allowed local movement of resident species. Video observation from 2001-2005 was used to evaluate environmental predictors of American shad (Alosa sapidissima) and sea lamprey (Petromyzon marinus) passage. The ecological effects of restoring connectivity to upstream habitat for gizzard shad (Dorosoma cepedianum) and blue catfish (Ictalurus furcatus) are also discussed. Regression analysis determined that the best predictor of increased daytime American shad passage is higher water temperatures and discharge and for increased daytime sea …
Genetic Assessment Of Rare Blackbanded Sunfish (Enneacanthus Chaetodon) Populations In Virginia, Diana Marie Kercher
Genetic Assessment Of Rare Blackbanded Sunfish (Enneacanthus Chaetodon) Populations In Virginia, Diana Marie Kercher
Theses and Dissertations
Enneacanthus chaetodon, the blackbanded sunfish, has become increasingly rare throughout its distribution in the Eastern United States. In Virginia, E. chaetodon maintains an endangered status and individuals persist in six populations. Mitochondrial DNA (mtDNA) and microsatellite data were assessed to determine the genetic characters and gene diversity of the Virginia populations. The results of these analyses were then compared to five additional populations; four from New Jersey and one from North Carolina that were known to have relatively good fitness and were not impacted severely by habitat alteration. The results of this study are relevant to selection of proper management …