27 research outputs found
Marine Algae of Whidbey Island, Washington
The history of marine algal collections along the coast of Whidbey Island dates back to the work of N. L. Gardner, who made extensive collections on the island from 1897 to 1901. Except for small incidental collections, no major effort has been applied to the Whidbey Island marine flora since Gardner \u27 s work. The herbaria of the University of Washington and of the University of British Colombia were examined but contain few specimens from the island. Dr. Richard Norris, University of Washington, made several collections at West Beach during the summers, from 1949 to 1951. Other known algal collections from the Puget Sound region do not include material from Whidbey Island .
Work herein reported covers a four year period from 1962-1966. At three locations collections were made on a seasonal basis: Camp Casey Beach (immediately north of Admiralty Head), West Beach, and Deception Pass. A lesser amount of work was done at Bush Point. One collection each was made at Double Bluffs in Useless Bay and at East Point on the east side of the island. Observations, which were made as a part of a general Puget Sound survey for Zostera marina L. during 1962-1963 , substantiate remarks to be made concerning distribution patterns and ecological conditions existing on t he east side of Whidbey Island
Lateral Zonation of Trees along a Small Ohio Stream
Author Institution: Department of Botany and Bacteriology, Ohio Wesleyan UniversityRiparian-vegetation patterns along a small stream in Ohio were examined with multivariate and graphical analyses. The study focused on elevational differences in larger tree species (>10 cm DBH = diameter at breast height) on a floodplain bench, floodplain slope, and upland terrace. The three habitat zones showed differences in floral assemblages related to the flooding tolerance of tree species, the floodplain bench showing ash-maple dominance and the other habitats yielding maple-beech-oak dominance. The floral differences were likely attributable to natural and human impacts, particularly stream flooding and possibly past logging. The results and a literature review suggest that hydrologic disturbances (for example, flooding) create predictable, parallel patterns in floral assemblages along a lateral (stream-edge to upland) gradient. Riparian assessments in the lateral dimension can provide information to predict the effects of anthropogenic instream-flow alterations on riparian ecosystems, including small tributaries
Explorations, Vol. 4, No. 3
Articles include:
Cover: Trophy: MooseHorn, from the Trophy Series, by Caellaigh B. Desrosiers.
Editorial Reflections, by Carole J. Bombard
North Cascade Glacier Climate Project, by Mauri Pelto
Stained Glass Molecules, by Anne P. Sherblom
Lobsters Inside-Out: A Guide to the Maine Lobster
Community Forestry: UMaine Cooperative Extension Service, by Nancy E. Coverstone and William D. Lilley
Where Are They Now? — Robert F. LaPrade, M.D. ’81
Little Critters with a Big Job: Ciliated Protozoa and the Gulf of Maine Food Chain, by Marcia Gauvin from a paper by Charles Gregory
The Innovation of Tradition: Low-Cost, Low-Input Alternatives for Maine Farmers, by Marcia Gauvin
Just What IS An Animal? Preschoolers Investigate Merging Two Cultures: Our Cover Artist, by Caellaigh Bennett Derosiers
Freezing and Photosynthesis, by Steven R. Dudgeon, Ian R. Davison, and Robert L. Vada
Factors affecting the determination of threshold doses for allergenic foods: How much is too much?
Background: Ingestion of small amounts of an offending food can elicit adverse reactions in individuals with IgE-mediated food allergies. The threshold dose for provocation of such reactions is often considered to be zero. However, because of various practical limitations in food production and processing, foods may occasionally contain trace residues of the offending food. Are these very low, residual quantities hazardous to allergic consumers? How much of the offending food is too much? Very little quantitative information exists to allow any risk assessments to be conducted by the food industry. Objective: We sought to determine whether the quality and quantity of existing clinical data on threshold doses for commonly allergenic foods were sufficient to allow consensus to be reached on establishment of threshold doses for specific foods. Methods: In September 1999,12 clinical allergists and other interested parties were invited to participate in a roundtable conference to share existing data on threshold doses and to discuss clinical approaches that would allow the acquisition of that information. Results: Considerable data were identified in clinical files relating to the threshold doses for peanut, cows\u27 milk, and egg; limited data were available for other foods, such as fish and mustard. Conclusions: Because these data were often obtained by means of different protocols, the estimation of a threshold dose was very difficult. Development of a standardized protocol for clinical experiments to allow determination of the threshold dose is needed
Agricultural Effects on Streams and Rivers: A Western USA Focus
Globally, croplands and rangelands are major land uses and they have altered lands and waters for millennia. This continues to be the case throughout the USA, despite substantial improvements in treating wastewaters from point sources—versus non-point (diffuse) sources. Poor macroinvertebrate assemblage condition occurs in 30% of conterminous USA streams and rivers; poor fish assemblage condition occurs in 26%. The risk of poor fish assemblage condition was most strongly associated with excess nutrients, salinity and sedimentation and impaired riparian woody vegetation. Although the Clean Water Act was passed to restore and maintain the integrity of USA waters, that will be impossible without controlling agricultural pollution. Likewise, the Federal Land Policy and Management Act was enacted to protect the natural condition of public lands and waters, including fish habitat, but it has failed to curtail the sacred cows of livestock grazing. Although progress has been slow and spotty, promising results have been obtained from basin and watershed planning and riparian zone protections
OXYGEN UPTAKE AND RESPONSES TO RESPIRATORY STRESS IN SEA URCHINS
Volume: 132Start Page: 16End Page: 2
Regeneration of thallus fragments of Rhodochorton purpureum (Rhodophyceae, Nemalionales)
Recruitment of Ascophyllum Nodosum: Wave Action as a Source of Mortality
The brown alga Ascophyllum nodosum is a dominant rocky intertidal organism throughout much of the North Atlantic Ocean, yet its inability to colonize exposed or denuded shores is well recognized. Our experimental data show that wave action is a major source of mortality to recently settled zygotes. Artificially recruited zygotes consistently exhibited a Type IV survivorship curve in the presence of moving water. As few as 10, but often only 1 relatively low energy wave removed 85 to 99% of recently settled zygotes. Increasing the setting time for attachment of zygotes (prior to disturbance from water movement) had a positive effect on survival. However, survival was significantly lower at high densities, and decreased at long (24 h) setting times, probably as a result of bacteria on the surface of zygotes. Spatial refuges provided significant protection from gentle water movement but relatively little protection from waves
Social-Ecological Scale Mismatches and the Collapse of the Sea Urchin Fishery in Maine, USA
Scale mismatches result in incomplete or ambiguous feedback that impairs the ability to learn and adapt and, ultimately, to sustain natural resources. Our aim is to examine the sea urchin fishery in Maine, USA to better understand the multiscale, social, and biophysical conditions that are important for the design of institutions that might be able to sustain the resource. During the late 1980s and 1990s, the Maine sea urchin fishery was a classic gold rush fishery. In the beginning, the fishery was characterized by an abundant resource with little to no harvesting activity, followed by a period of rapid increase in landings and effort that led to a subsequent and persistent decline in the sea urchin population and a significant reduction in effort. We conducted semistructured interviews with scientists and experienced fishermen to understand the multiscale, social, and biophysical conditions that influence fishermen's harvesting strategies, and the implications of this for the design of institutions for successful resource management. The current co-management system includes an advisory body made up of industry members and scientists it also includes limited entry, and additional input control mechanisms. Many of these measures are implemented at a very broad scale; however, we find that the ecological conditions relevant to the sustainable processes occur at the scale of individual fishing sites or ledges, which is a much finer scale than current management. Therefore, the co-management system maintains an open access system and leaves few incentives for the development of sustainable harvesting strategies among fishermen. The clear suggestion is that the appropriate management system would be one that directly addresses the fine scale ecological and social dynamics within this fishery and gives fishermen property rights over individual ledges (for example, leases). After having briefly reviewed experiences in Canada and Chile, we found that knowledge of the coupled natural and human system at the fine scale is necessary if we are to assess the feasibility of area management in this fishery, because what works in one fishery does not necessarily work in another