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The Effect Of Physical And Biological Site Characteristics On The Survival And Expansion Of Transplanted Eelgrass (Zostera Marina L), Ryan Clark Davis

Doctoral Dissertations

Eelgrass (Zostera marina L.) was transplanted at seven sites along the New Hampshire side of the Piscataqua River in 1993 and 1994. The eelgrass transplanting was one component of the New Hampshire Port Authority Mitigation Project, designed to mitigate for impacts to natural resources associated with the expansion of the port facility. Over 2.5 hectares of eelgrass were transplanted using a newly developed transplanting technique, the horizontal rhizome method, and ultimately created eelgrass habitat at several sites. However, transplants did not survive at any of the intertidal areas planted and were greatly reduced at several subtidal sites. The intertidal transplants …

The Long-Term Effects Of Disturbance On Nitrogen Cycling And Loss In The White Mountains, New Hampshire, Christine Lynn Goodale

Doctoral Dissertations

Theories of nitrogen retention suggest that N cycling and loss should increase with ecosystem successional age and with chronic N deposition over time (N saturation). These factors both affect northeastern U.S. forests, most of which receive elevated rates of N deposition and have experienced past disturbances by wind, logging, fire, or agriculture. This work examined the long-term (80--110 year) effects of land-use history on nitrogen cycling and loss in the White Mountains, New Hampshire. Historical land-use maps were used to identify a network of watersheds and plots containing burned, logged, or old-growth forests. Nitrate-N fluxes from old-growth watersheds exceeded those …

The Ship In The Forest: New England Maritime Industries And Coastal Environment, 1630-1850, William Burgess Leavenworth

Doctoral Dissertations

This work examines the relationship between New England's maritime industries and the coastal ecotone, from Massachusetts Bay to Penobscot Bay and occasionally beyond, between 1630 and 1850. It begins with the early English use of the littoral ecosystem, and describes the effects of expanding maritime development and related industries---shipbuilding, fishing, farming and forestry---on that ecosystem until the late ante-bellum era. It also investigates the role of the coastal ecosystem in the development of New England's colonial and early Federal political structure and economies, and describes in some detail the role of strategic coastal resources in the wars of the 17th …

Controls On Spatial And Temporal Variability In Nitrous Oxide Fluxes Across A Tropical Rainforest Ecosystem In The Luquillo Experimental Forest, Puerto Rico, Claire Patricia Mcswiney

Doctoral Dissertations

Nitrous oxide (N2O) is a trace gas that contributes to the greenhouse effect and participates in the reactions that destroy stratospheric ozone. Soil microbial processes are significant producers of this trace gas, particularly in tropical areas, which are considered major sources in the global N2O budget. Nitrous oxide fluxes to the atmosphere are variable in space and time. In this study, spatial and temporal variability in surface N2O fluxes were assessed as well as the major environmental controls on N2O production for a tropical rainforest watershed in northeastern Puerto Rico. A static chamber technique was used to assess surface fluxes …

Paleoclimatic Significance Of Insoluble Microparticle Records From Canadian Arctic And Greenland Ice Cores, Christian Michel Zdanowicz

Doctoral Dissertations

The past and present variability of climate in the Arctic region is investigated using ice core records of atmospheric dust (microparticles) and volcanic aerosols developed from the Canadian Arctic and Greenland. A high-resolution, 10 4-year long proxy record of atmospheric dust deposition is developed from an ice core (P95) drilled through the Penny Ice Cap, Baffin Island. Snowpit studies indicate that dust deposited on the Penny Ice Cap are representative of background mineral aerosol, and demonstrate that the variability of dust fallout is preserved in the P95 core at multi-annual to longer time scales. The P95 dust record reveals a …

Atmospheric Transport And Deposition Of Water -Soluble Nitrogen To The Gulf Of Maine, Carolyn Estelle Jordan

Doctoral Dissertations

An intensive sampling program was carried out from May 1994 through November 1997 on the shore of the Gulf of Maine in New Castle, New Hampshire. Daily (24 hour averages) samples of bulk aerosol and gas phase HNO3, precipitation, and 20 aerosol size distributions were obtained. Particulate NH4+ and gas phase HNO3 were the dominant water-soluble nitrogen species in the atmosphere. Nitrate was the dominant inorganic nitrogen ion in precipitation.

These samples were used with 1000 hPa streamlines to classify sampled air masses according to their surface level transport and chemistry. Overall, mixed conditions occurred in 42% of the samples, …