DISSOLVED AND GASEOUS FLUXES OF CARBON AND NITROGEN FROM URBAN WATERSHEDS OF THE CHESAPEAKE BAY

Carbon and nitrogen loading to streams and rivers contributes to eutrophication as well as greenhouse gas (GHG) production in streams, rivers and estuaries. My dissertation consists of three research chapters, which examine interactions and potential trade-offs between water quality and greenhouse gas production in urban streams of the Chesapeake Bay watershed. My first research project focused on drivers of carbon export and quality in an urbanized river. I found that watershed carbon sources (soils and leaves) contributed more than in-stream production to overall carbon export, but that periods of high in-stream productivity were important over seasonal and daily timescales. My second research chapter examined the influence of urban storm-water and sanitary infrastructure on dissolved and gaseous carbon and nitrogen concentrations in headwater streams. Gases (CO2, CH4, and N2O) were consistently super-saturated throughout the course of a year. N2O concentrations in streams draining septic systems were within the high range of previously published values. Total dissolved nitrogen concentration was positively correlated with CO2 and N2O and negatively correlated with CH4. My third research chapter examined a long-term (15-year) record of GHG emissions from soils in rural forests, urban forest, and urban lawns in Baltimore, MD. CO2, CH4, and N2O emissions showed positive correlations with temperature at each site. Lawns were a net source of CH4 + N2O, whereas forests were net sinks. Gross CO2 fluxes were also highest in lawns, in part due to elevated growing-season temperatures. While land cover influences GHG emissions from soils, the overall role of land cover on this flux is very small (< 0.5%) compared with gases released from anthropogenic sources, according to a recent GHG budget of the Baltimore metropolitan area, where this study took place.

TROMBONE MUSIC OF SCANDINAVIA: A STUDY OF TROMBONE SOLO AND CHAMBER WORKS FROM SWEDEN, NORWAY, AND DENMARK

This dissertation project aims to establish Scandinavian trombone solo and chamber works as a major contribution to the trombone repertoire. From the late 19th century to modern day, Scandinavian composers have produced a steady output of trombone works of substantial musical quality. Deep-rooted in the traditions of strong military wind bands, Scandinavia has also produced an unusual number of trombone virtuosos, ranging from those holding positions in leading orchestras, and internationally renowned pedagogues, to trombonists enjoying careers as soloists. In this study I propose that it is the symbiotic relationship between strong performers and traditionally nationalist composers that created the fertile environment for the large number of popular trombone solo and chamber repertoire not seen in any other region besides the Paris Conservatory and its infamous test pieces. I also interpret the selected repertoire through the prism of nationalism and influence of folk music, and convey that the allure of the mystic Nordic folk influences enhances the appeal of the Scandinavian trombone repertoire to world-wide audiences and performers. The dissertation project was realized over three solo recitals, each showcasing the music of Sweden, Norway, and Denmark respectively. For each program, I looked to choose a standard work from the trombone solo repertoire, a work written for or by a native virtuoso, and a lesser-known work that warrants the attention of other performers for its musical qualities. The recital of Swedish music presented Mandrake in the Corner by Christian Lindberg, Subadobe by Frederik Högberg, A Christian Song by Jan Sandström, and Concertino for trombone and strings by Lars-Erik Larsson. The recital of Norwegian music presented Concerto for Trombone op. 76 by Egil Hovland, Ordner Seg by Øystein Baadsvik, Elegi by Magne Amdahl, and Concerto in F major by Ole Olsen. The recital of Danish music presented Rapsodia Borealis by Søren Hyldgaard, Madrigal by Bo Gunge, Romance for trombone and piano by Axel Jørgensen, Concerto for trombone by Launy Grøndahl, and Three Swedish Tunes by Mogens Andresen. Through the performance of works from these three countries, the dissertation establishes Scandinavia as a rich source of solo trombone repertoire perpetuated by nationalist composers and virtuosos, as well as providing a brief survey of Scandinavian trombone works of various instrumentation and difficulty levels to be enjoyed by student, professional, and amateur performers and their audience.