Delmarva Peninsula Research Articles

Revolution downeast: the war for American independence in Maine

In the late 18th century, the area that would become the state of Maine was still part of Massachusetts - a colony of a colony within the sprawling British Empire. This account of the Revolution downeast is the story of a people initially too preoccupied with day-to-day survival to pay much attention to the rising temper of imperial controversy. When war did erupt, many Maine colonists hoped that their geographical isolation and the presence of native tribes - many of which were long-standing British foes - would protect them from royal forces in nearby Nova Scotia. But this was not to be. Soon enemy privateers plundered the region's coastal settlements and shipping, and in 1779 the British established a base at the mouth of the Penobscot River. Heartened by the British presence, local loyalists sprang into action and transformed a revolution into a bitter civil war. For Maine, as for many other areas of the rebelling colonies, the struggle with England proved to be a divisive ordeal that heightened pre-war social, economic, and political differences. James S. Leamon discusses Maine's revolutionary experience in the context of other regions of conflict - Georgia, Long Island, Maryland's Delmarva Peninsula, and the Carolina back country - where disrupted economies, British incursions, guerrilla warfare, and shifting loyalties defined the Revolution.

Occurrence of Nitrate in Groundwater—A Review

AbstractThe results of federal, state, and local surveys, which included more than 200 000 NO3‐N data points, are summarized in this review of NO3 in groundwater in the USA. The levels of NO3‐N are associated with source availability and regional environmental factors. In regions where well‐drained soils are dominated by irrigated cropland, there is a strong propensity toward the development of large areas with groundwater that exceeds the maximum contaminant level of 10 mg/L NO3‐N. Most of these areas are west of the Missouri River where irrigation is a necessity. Aquifers in highly agricultural areas in the southeastern USA reportedly are not contaminated. Vegetative uptake and denitrification in this warm, wet, C‐rich environment are responsible for the natural remediation of NO3 in shallow aquifers. In the Middle Atlantic states and the Delmarva Peninsula, localized contamination occurs beneath cropped, well‐drained soils that receive excessive applications of manure and commercial fertilizer. Extensive tile drainage has for the most part prevented a NO3 problem in the groundwater of the Corn Belt states. Throughout the USA there are recurring themes. They include a decrease in NO3‐N levels with depth; lower NO3‐N levels in shallow wells (< 8 m); and a significant increase in NO3‐N in older wells and in wells with poor construction. The factors affecting the distribution of NO3 in aquifers are complex and poorly understood. Interdisciplinary studies using discrete depth sampling, hydrogeological indicators, isotopic tracers, and microbiological techniques are necessary to unravel the complex dynamics.

Pesticides in Shallow Groundwater in the Delmarva Peninsula

AbstractA regional study of the areal and depth distribution of pesticides in shallow groundwater in the Delmarva Peninsula of Delaware, Maryland, and Virginia was done to (i) relate the pesticides detected to landscape and shallow subsurface features, and (ii) evaluate aquifer vulnerability and the potential contamination of drinking‐water supplies. Water samples collected at 100 wells from 1988 to 1990 were analyzed for concentrations of 36 pesticides, four metabolites, and other constituents. The most commonly detected residues were atrazine, cyanazine, simazine, alachlor, metolachlor, and dicamba. Concentrations were low; few exceeded 3 µg L−1. Most detections correlate with the intensive use of these herbicides in three widely distributed and commonly rotated crops—corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and small grain—particularly if grown in well‐drained soils. Most detections occurred in samples collected from shallow wells screened within 10 m of the overlying water table. The shallow depth distribution of most residues is consistent with their suspected history of use (ca. 20 yr), and patterns in shallow groundwater flow in the surficial aquifer in the study area. The areal and depth distributions of detectable residues in groundwater did not correlate with a vulnerability index, nor any of the component scores developed to estimate that index using the DRASTIC method. The shallow depth of most detections also indicates why few samples from water‐supply wells in this study had measurable concentrations of pesticides; most supply wells are deeper than 10 m below the water table. The low number of contaminated samples from supply wells implies that deep groundwater currently (1992) used for drinking generally does not contain detectable pesticide residues.

Effect of forested wetlands on nitrate concentrations in ground water and surface water on the Delmarva Peninsula

The Delmarva Peninsula is an extensively farmed region in which nitrate from commercial fertilizers and poultry has entered the ground water and streams. The peninsula contains forested wetlands in a variety of settings, and their size and location are a result of the surrounding hydrologic and soil conditions. Three regions, here referred to as hydrogeomorphic regions, were selected for study. Each region has characteristic geologic and geomorphic features, soils, drainage patterns, and distribution of farmland, forests, and forested wetlands. In all three regions, forested wetlands generally occupy poorly drained areas whereas farmlands generally occupy well-drained areas. The three hydrogeomorphic regions studied are the well-drained uplands, the poorly drained uplands, and the surficial-confined region. The well-drained uplands have the largest amount of farmland and the smallest amount of forested wetlands of the three regions; here the forested wetlands are generally restricted to narrow riparian zones. The poorly drained uplands contain forested wetlands in headwater depressions and riparian zones that are interspersed among well-drained farmlands. The surficial-confined region has the smallest amount of farmland and largest amount of forested wetlands of the three regions studied. Wetlands in this region occupy the same topographic settings as in the poorly drained uplands. Much of the farmland in the surficial-confined region was previously wetland. Nitrate concentrations in ground water and surface water on the peninsula range widely, and their distribution reflects (1) the interspersion of forests among farmland, (2) hydrogeologic conditions, (3) types of soils, and (4) the ground-water hydrology of forested wetlands. The well-drained uplands had higher median nitrate concentrations in ground water than the poorly drained uplands or the surficial-confined region. The highest nitrate concentrations were in oxic parts of the aquifer, which are beneath well-drained soils that are farmed, and the lowest were in anoxic parts of the aquifer, which are beneath poorly drained soils overlain by forested wetlands. The effect of forested wetlands on water quality depends on the hydrogeologic conditions, extent of farming, and type of soils. The three regions contain differing combinations of these factors and thus are useful for isolating the effects of forested wetlands on water quality.

Organization and Structure of Clouds and Precipitation on the Mid-Atlantic Coast of the United States. Part VI: The Synoptic Evolution of a Deep Tropospheric Frontal Circulation and Attendant Cyclogenesis

Interactions between an upper-level frontal system and an initially weak surface cold front resulted in the production of a deep, precipitating frontal structure over the south Atlantic states on 26–27 January 1986. Attendant with the intensification of the frontal circulation was the development of an intense marine cyclone off the Delmarva peninsula. The increase in frontal-circulation strength is attributed to a favorable vertical superposition of the surface frontal trough and the upper-level frontogenetic horizontal deformation field that resulted in a deep column of divergence over the surface frontal trough. The surface cyclone developed partly, and indirectly, in response to the increase in warm-air advection in the lower stratosphere, which was directly related to an increase in the slope of the dynamic tropopause. The increase in the slope of the tropopause is hypothesized to have been the result of the combined effect of adiabatic advection of low tropopause height in the cold air of the upper trough and the latent heating associated with the onset of deep convection during the frontal development.

Derivation of site‐specific ammonia criteria for an effluent‐dominated headwater stream

AbstractThe present study was designed to derive appropriate ammonia standards for a freshwater, wooded stream on the Delmarva Peninsula (eastern shore of the United States) composed almost entirely of wastewater effluent for at least four months of the year. Representative species acute and chronic toxicity tests were performed at 20° (summer) and 12°C (winter) to obtain seasonal standards. Acute toxicity tests using fathead minnow and Daphnia magna suggested that the site water had no effect on un‐ionized ammonia toxicity. However, resident species appeared to be relatively insensitive to acute exposures of un‐ionized ammonia. Warm‐water LC50s adjusted for pH = 8.0 and 20°C ranged between 1.02 and 2.73 mg/L for those tests in which an LC50 could be calculated. If acute no‐observed‐effect concentrations (NOECs) (approximately LC25) were used, bluegill was most sensitive (NOEC = 0.295 mg/L), followed by Crangonyx (amphipod) and Menidia (silverside). Warm‐water chronic testing indicated that Rana (leopard frog) was most sensitive, followed by bluegill and amphipod. Cold‐water acute tests yielded definitive LC50s between 0.53 (bluegill) and 1.91 mg/L (amphipod). Hyla crucifer (spring peeper) and juvenile bluegill were most sensitive in chronic cold‐water testing. Final acute values (FAVs) of 0.62 and 0.30 mg/L NH3 were obtained for 20 and 12°C, respectively. The geometric mean of acute‐to‐chronic ratios (ACR) based on unionized ammonia were 7.2 and 5.7, for 20 and 12°C, respectively. The final chronic values (FCVs) or maximum 4‐d average concentrations at 20 and 12°C were 0.09 and 0.05 mg/L NH3, respectively. Un‐ionized ammonia acute toxicity to vertebrate freshwater species (fish and tadpoles) was inversely related to temperature, whereas invertebrates often exhibited the opposite trend. Chronic testing, however, suggested that most species were more sensitive to NH3 at 20 than 12°C. This study suggests that the ACR developed by the U.S. Environmental Protection Agency (EPA) for warm‐water streams may be overly conservative for very small streams in which species diversity is naturally low.

Effects of Agriculture Chemicals on Natural Geochemistry of Shallow Groundwater, Delmarva Peninsula, Delaware, Maryland, and Virginia

Effects of Agriculture Chemicals on Natural Geochemistry of Shallow Groundwater, Delmarva Peninsula, Delaware, Maryland, and Virginia

Seismic stratigraphy and coastal drainage patterns in the Quaternary section of the southern Delmarva Peninsula, Virginia, USA

Seismic-stratigraphic analysis of the coastal zone and inner shelf of Virginia's southern Delmarva Peninsula has revealed three geochronologically significant surfaces of post-Tertiary age that impose a relative chronostratigraphic framework on Quaternary marine transgressive and regressive events. Characteristics of these surfaces indicate that two are sequence boundaries, and one is a ravinement surface. Lying at depths of 18–70 m (msl datum), the LP b surface (a late Pleistocene basal unconformity) represents the sequence boundary separating the Tertiary Chesapeake Group from the overlying late Pleistocene Nassawadox Formation. High relief (approximately 50 m) on the LP b surface is associated with large fluvial channels. Higher in the stratigraphic section, the LP r, surface is found at depths of 6–28 m, and corresponds to a late Pleistocene transgressive, or ravinement surface. The surface dips southeastward with a regional dip of 0.04° and has local relief of less than 2 m. The LP r surface may represent a ravinement which extended to the west side of the Chesapeake Bay prior to the development of the Nassawadox barrier spit. However, the LP r surface may steepen between the axis of the southern Delmarva Peninsula and the Holocene lagoon to form a shoreface attached to one of several known late Pleistocene shorelines. Lying at depths of 0–20 m, the H b surface is a basal unconformity that marks the Holocene sequence boundary. It deepens seaward, with maximum local relief of about 15 m, and has a topographic expression very similar to the present-day lagoonal drainage pattern. Maximum thicknesses of Holocene and Pleistocene sediments (12 and 70 m, respectively) are found above channels on the H b and LP b surfaces. The Pleistocene channels are large and limited in number and represent high-order channels of a drainage system that drained the Piedmont and Coastal Plain. The greater density of low-order stream channels on the H b surface suggests a relationship to much smaller drainage basins that were confined to the seaward part of the Coastal Plain east of the Delmarva Peninsula. These late Wisconsinan smaller H b channels do not re-occupy the former drain paths of the much larger high-order LP b channels.

AN EVALUATION OF A WIDE RANGE OF JOB-GENERATING ACTIVITIES FOR RURAL COUNTIES

The job-generating activities of governments and civic groups in fifteen rural counties on the Delmarva Peninsula and southern Maryland are examined through more than 175 informant interviews and field work. These counties engaged in a wide range of job-generating activities and many of these were directed toward business recruitment. When community leaders ranked activities for their impacts on jobs, industrial parks received the most high ranks, economic development units second and tourism promotion third. Special financial arrangements for relocating or new businesses were evaluated as very important on average to economic development and grantsmanship was a successful activity in all counties though it never ranked as the first or second most productive job-generating activity. Guidance on economic development strategies for rural counties are derived from the findings.

A Harvest of Shame Revisited: Substance Use and Abuse Within the Delmarva Migrant Stream

After realizing some 15 years ago that we had not "turned the corner" on drug abuse, the substance abuse treatment community became more deliberate in waging this war by developing culturally, ethnically, age-, and gender-specific intervention modalities to ensure a more equitable continuum of care. Additionally, research efforts began to reflect the disparities of health and longevity between ethnic minority and nonethnic minority populations which culminated in the U.S. Department of Health and Human Services Task Force on Black and Minority Health Report of 1986. This comprehensive and much acclaimed report contributed significantly to a knowledge base and provided a frame of reference for health planning and service delivery. But the information contained therein was overwhelmingly focused on urban areas. A literature review reveals a paucity of information on access to care in rural communities, especially those with populations consisting of seasonal and migrant farmworkers. This population has received little visibility since "Harvest of Shame" was aired on national television 30 years ago. An analysis of substance use and abuse among this population in the Delmarva (Delaware, Maryland, Virginia) peninsula as well as an assessment of services available to them is the intent of this report. Information for this report was developed from secondary analysis of program reports, needs assessments, policy analyses, and interviews with service providers. A preliminary analysis suggests that there appears to be increased substance abuse and drug trafficking among this population. There also tends to be a greater understanding of Hispanic American use and abuse than that of black Americans and other ethnic groups (e.g., Mexicans, Guatemalans, Haitians) in the migrant stream. Finally, substance abuse is encouraged and access to care is hampered by sociocultural factors and stresses such as school-related problems, lack of vertical mobility, language problems, and poor integration and coordination of the service delivery systems.

Response of Lima Beans to Irrigation on the Delmarva Peninsula

Yield data and evapotranspiration rates were measured on lima beans for four years. The treatments included non-irrigation, full season irrigation, and irrigation from flowering to harvest (partial irrigation). Partial irrigation increased lima bean yields 47% compared to non-irrigation. Total evapotranspiration from flowering to harvest for the irrigated treatments ranged from 182 to 320 mm (7.2 to 12.6 in.). Peak evapotranspiration rates ranged from 6.4 to 9.1 mm/day (0.25 to 0.36 in./day). Total annual costs for a 40.5 ha (100 ac) center pivot system for lima beans would be $285.04/ha ($115.44/ac).

Comparison of bacterial dynamics in tidal creeks of the lower Delmarva Peninsula, Virginia, USA

Bacterial biornass, abundance, and product~vity were greater in 3 tidal marsh creeks on the Chesapeake Bay side of the lower Delmarva Peninsula than in nearby creeks of the seaside coastal lagoon complex (biomass: 462 and 71 ng C ml' ; abundance: 12 X 10' and 3.8 X 106 cells ml-l ; productivity: 46 and 7.3 ng C rnl-' h-'; bayside and seaside respectively). Bacterial cell-size distributions were also significantly different between the seaside and bayside creeks, with a larger proportion of smaller cells dominating samples from the seaside creeks. Bayside and seaside concentrat~ons of total suspended solids (TSS) and dissolved organic carbon (DOC) were similar (approximately 49 mg 1.' TSS and 3.5 mg I ' DOC) The amount of organic matter (OM) and chlorophyll a was higher in the bayside creeks, while inorganic N and P concentrations were higher in the seaside creeks (OM. 9 0 and 3.4 mg 1 l ; chlorophyll a. 6 0 and 4.1 g 1.'; PO, 0.2 and 1.2 FM; NH,' 0.6 and 1.2 ubI; bayside and seaside respectively). The high inorganic nutrient pools combined with the low levels of bacterial productivity suggest that bacterial production is not l~nli ted by N or P in the seaside creeks and that the amount of carbon moving through the bacterial loop is much less than on the bayside. In fact, DOC turnover times were much longer for the seaside (22 d ) than for the bayside (6 d ) . Reasons for the observed differences in bacterial dynamics for the bay and seasides are not known specifically, but may be related to differences in the source of the DOC (marsh grass vs phytoplankton), grazlng on the bacterial cells, or bacterial community structure

Comparison of bacterial dynamics in tidal creeks of the lower Delmarva Peninsula, Virginia, USA

Comparison of bacterial dynamics in tidal creeks of the lower Delmarva Peninsula, Virginia, USA

Pathology of lymphoid organs with emphasis on immunosuppression

A review of the literature is presented to include recent diagnostic and research histopathology accessions from poultry produced on the Delmarva peninsula region of the U.S.A. Emphasis is placed on immunosuppression (IS) and pathology of primary lymphoid organs of the chicken. The evolutionary relationship of the avian and mammalian lymphoid systems is based on a common reptilian past with 160 million years of evolutionary dichotomy. Four methods used to assess IS anatomically include: (1) recognition of marked reduction of lymphocytes in both primary and secondary lymphoid organs; (2) recognition of diseases commonly associated with IS; (3) recognition of known immunosuppressive diseases; (4) germinal center enumeration. An experimental method of qualifying and quantifying IS related to single or multiple insults is explored through the use of germinal center enumeration. The effect of stress and inanition on avian lymphocytes must be considered in histological evaluations as chickens are a steroid sensitive species.

A Report of the Archaeological Investigations at the House of Thomas Cuff, a Free Black Laborer, 108 Cannon Street, Chestertown, Kent County, Maryland

Archaeological inquiry at the home of an antebellum free black laborer in Chestertown, Maryland, has provided an opportunity to examine the material culture of 19th century African Americans on the Eastern Shore, a subject and a region that has received comparatively little historical archaeological attention. While the conditions of the excavation were not optimal, the large artifact assemblage recovered, coupled with architectural and historical evidences, can be used to formulate some general conclusions about antebellum blacks on the Eastern Shore. The results of the investigations at the site suggest that Thomas Cuff, a former slave and slave owner himself, and one of the more prominent members of the black community in Chestertown, was possessed of material culture that was representative of the laboring free blacks on the 19th century Delmarva Peninsula.

The Woodland I—Woodland II Transition in the Delmarva Peninsula and Southeast Pennsylvania

The transition between Woodland I and Woodland II periods (ca. A.D. 800-A.D. 1000) is one of the most pronounced cultural changes seen during the prehistoric occupation of the Delmarva Peninsula and southeastern Pennsylvania. Cultural changes manifested in the local archaeological record include changes in site distributions and settlement patterns, the abandonment of some sections of certain drainage basins, the demise of regional exchange systems, the demise of local complex socio-political systems, the appearance of new and diverse ceramic technologies and ceramic design systems, and the appearance of certain special exotic artifact forms and mortuary; ceremonialism traits which are virtually identical to similarly dated archaeological complexes of the eastern Great Lakes, central Pennsylvania, and western Virginia. The Woodland I/Woodland II cultural discontinuity is probably the result of a migration of Algonkian-speaking groups into the area.

Selective extinction and survival across the Cretaceous/Tertiary boundary in the northern Atlantic Coastal Plain

The inner Atlantic Coastal Plain in New Jersey and the Delmarva Peninsula is underlain by an Upper Cretaceous-lower Tertiary sequence of marine and paralic sand, clay, and glauconitic beds. Campanian, Maastrichtian, Danian, and Thanetian deposits are especially fossiliferous and yield a succession of marine faunas that reveal a pattern of selective extinction and survival across the Cretaceous/Tertiary (K/T) boundary in this area. Cretaceous benthic invertebrate communities are dominated by oysters and other semi-infaunal and infaunal molluscs with planktotrophic larval stages. These are replaced in the Danian by brachiopod-dominated communities that are composed of epifaunal benthos with a variety of nonplanktotrophic reproductive strategies. A similar pattern is observable in the nektonic cephalopod populations in this sequence; the typical ammonites of the Cretaceous became extinct at the K/T boundary, whereas the nautilids survived. Ammonites are thought to have had a planktotrophic larval stage, whereas nautilids are known to lay large lecithotrophic eggs. This pattern of differential survival is attributed to the planktonic population crash at the K/T boundary which placed planktotrophically reproducing species at a disadvantage while favoring the varied groups that practiced alternative reproductive strategies.

Changes in poultry litter toxicity with simulated acid rain

The Delmarva Peninsula on the Eastern Shore of Maryland ranks 4th in the nation in poultry production and generates 9,500 metric tons of poultry manure/litter per day. The poultry litter contains many macro and micro nutrients and is an excellent source of fertilizer. The litter also contains antibiotics, heavy metals, hormones and many microorganisms. Land application of this litter has been the only means of its utilization and disposal. With rainfall, surface water run-off (leachate), from land on which litter has been applied, reaches the Cheasapeake Bay from this region. This leachate with its high organic and inorganic salt contents and high biochemical oxygen demand can severely disrupt the aquatic life and cause fish kills. The objective of this research was to study the effect of simulated acid rain (pH 3, 4 and 5) on the toxicity of poultry litter extracts.

Initial Results In The Development Of A Synthetic Aperture Microwave Radiometer

A radiometer that measures the complex correlation of the voltage from pairs of antennas at many different baselines is being developed. Each baseline produces a sample point in the Fourier transform of the scene, and a map of the scene is obtained after all measurements have been made by inverting the transform. A substantial reduction in the antenna collecting area required compared to a conventional imaging radiometer can be obtained in this manner. An aircraft prototype being developed is a hybrid which uses real aperture antennas to obtain resolution along-track (stick antennas) and uses aperture synthesis to obtain resolution across-track. The prototype was flight-tested aboard the NASA P-3 in June 1988. During this flight a map was made of the Delmarva Peninsula south of NASA's Wallops Flight Facility. This initial map shows the major land/water features and compares very favorably with a Landsat image of the area, suggesting a bright outlook for the development of this technique in the future.

Using a forest stand simulation model to examine the ecological and climatic significance of the late-quaternary pine-spruce pollen zone in eastern Virginia, U.S.A.

Full-glacial pollen records from southeastern United States are composed primarily of pine and spruce, with lesser amounts of fir, birch, and oak. A simulation model of forest dynamics was used to reconstruct the composition and structure of these forests on the Delmarva Peninsula of Virginia, where pollen data were available to test the model, and climate and soils data were available to drive the model. Reconstructed annual precipitation and summer air temperature were consistent with modern analog estimates from the pollen record. Annual precipitation was also consistent with climates simulated by atmospheric general circulation models, but summers were colder. Correcting these simulated climates for possible errors resulted in summer air temperature consistent with our estimate. However, two alternative parameter sets relating simulated tree growth to air temperature sums precluded robust forest reconstructions. With one parameter set, the species dominating the simulated forests were not consistent with the pollen record. The other parameter set produced forests more consistent with paleoecological data, indicating that the climate was correct. These differences in simulated forest composition reflected inadequacies in the parameterization of air temperature effects in forest models.