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Seagrass beds have declined in Chesapeake Bay, USA as well as worldwide over the past century. Increased seston concentrations, which decrease light penetration, are likely one of the main causes of the decline in Chesapeake Bay. It has been hypothesized that dense populations of suspensionfeeding bivalves, such as eastern oysters (Crassostrea virginica), may filter sufficient seston from the water to reduce light attenuation and enhance seagrass growth. Furthermore, eastern oyster populations can form large three-dimensional reef-like structures that may act like breakwaters by attenuating waves, thus decreasing sediment resuspension. We developed a quasi-three-dimensional Seagrass-WavesOysters-Light-Seston (SWOLS) model to investigate whether oyster reefs and breakwaters could improve seagrass growth by reducing seston concentrations. Seagrass growth potential (SGP), a parameter controlled by resuspension-induced turbidity, was calculated in simulations in which wave height, oyster abundance, and reef/breakwater configuration were varied. Wave height was the dominant factor influencing SGP, with higher waves increasing sediment resuspension and decreasing SGP. Submerged breakwaters parallel with the shoreline improved SGP in the presence of 0.2 and 0.4 m waves when sediment resuspension was dominated by wave action, while submerged groins perpendicular to the shoreline improved SGP under lower wave heights (0.05 and 0.1 m) when resuspension was dominated by along-shore tidal currents. Oyster-feeding activity did not affect SGP, due to the oysters' distance from the seagrass bed and reduced oyster filtration rates under either low or high sediment concentrations. Although the current implementation of the SWOLS model has simplified geometry, the model does demonstrate that the interaction between oyster filtration and along-shore circulation, and between man-made structures and wave heights, should be considered when managing seagrass habitats, planning seagrass restoration projects, and choosing the most suitable methods to protect shorelines from erosion. [ABSTRACT FROM AUTHOR]

This article focuses on the conduct materials that construct behavior as a performance of racial character and African American's identity in early 20th-century in the U.S. It is stated that the conduct materials reveal complicated and contradictory visions of black change. It is emphasized that the emergence of conduct materials is useful in re-examining the elite's relationship to etiquette and a public audience.

Addresses the pageantry of African American children in the United States during the Harlem Renaissance from 1905-1925. Where the pageants were staged; Production themes; Description of the Harlem Renaissance; How playwrights adapt pageant conventions.

Examines the conflicting visions of the South in the book 'Memories of a Southern Woman of Letters,' by Grace King. Admiration of English intellectualism; Reason behind her reluctance to discuss the South; Attitude toward South's economic and psychic privation.