2 resultados para Continuum of moment conditions

em DRUM (Digital Repository at the University of Maryland)


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Since 1993 Atlantic menhaden has experienced sustained low juvenile production (recruitment) in the Chesapeake Bay. Factors controlling growth, abundance, and mortality of larval and juvenile menhaden change throughout ontogeny such that larval growth rates could carry over to juvenile growth and survival. The effects of winter thermal conditions on the hatch dates and growth of larval and juvenile Atlantic menhaden in Atlantic shelf and Chesapeake Bay habitats were examined using otolith (ear-stone) increment analyses and growth models. For 2010-2013, truncated hatch-date distributions provided evidence for a winter recruitment bottleneck in Atlantic menhaden caused by cold temperatures. Hatch-dates of surviving juveniles were skewed towards warmer months for years characterized by colder temperatures. Reduced larval growth rates, influenced by reduced temperature and food availability, carried over to juvenile growth rates. A growing degree-day model performed well in simulating observed juvenile growth rates in the Choptank River tributary of Chesapeake Bay.

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Intensive archaeological investigation was undertaken on an urban backlot in Annapolis, Maryland. Fieldwork was conducted on behalf of Historic Annapolis Foundation for the property's owners, King and Cornwall, Inc. Supplemental documentary research, an evaluation of existing conditions on the property, and below-ground excavation of a 35 X 70 ft. urban backlot were conducted. While the project was not a Section 106 compliance effort, the field methods and rationale for the site's investigation are comparable to those of standard Phase II site evaluations. Historical documentation attested to the fact that the 22 West Street Backlot, located along the western most edge of the Historic District of Annapolis, Maryland, had seen development and occupation since the first quarter of the eighteenth century. A substantial brick structure was known to have occupied the property in a series of altered forms for much of that period. This structure served a variety of purposes over time: a private residence in the eighteenth century, a boarding house in the nineteenth century (known as the National Hotel), a duplex in the early twentieth century, half of which remained in use until the structure was entirely razed in the 1970s after destruction by fire. Recovery and analysis of site formation processes (i.e., both cultural and natural transformations of the buried remains) indicated that sections of the site were disturbed to a depth of six feet. In contrast to what initially seemed a poor prognosis for site integrity, other areas of the backlot revealed numerous intact historical features and deposits. Structural remains from the dwelling and its associated outbuildings, additions, and attendant trash deposits were recovered. What was initiated as a program of limited testing evolved into a larger-scale undertaking that made use of largely hand-excavated units in conjunction with machine-assisted stripping of areas demonstrated to contain from four to six-foot deep sterile layers of fill. The current investigations provided a window into a portion of the city and period in its history not documented archaeologically. Moreover, this project provided valuable insight into the archaeology of the homelot within a lightly industrialized, urban context. Evidence was recovered of shifts in the layout and arrangement of the houselot as well as changing relations between individuals and the workplace--all within an urban context--an issue defined elsewhere in the archaeological literature as a significant one. No further investigations are recommended for the site, however, further analysis and interpretation of materials recovered are ongoing. In the event that the site were to undergo development, monitoring of any construction activity is recommended.