Nutrients limiting the Algal Growth Potential (AGP) in the Gulf of Riga, eastern Baltic Sea, in spring and early summer 1996

In May, June and July 1996, samples wcre collected along one transect greatly influenced by river discharge (eastern side of the gulf), along one transect slightly influence by river discharge (western side), at one station Iocated in the mouth of the main river (River Daugava), at one station located in the center of the Gulf and at several nearshore locations of the western side. Ratios of rnolecular concentrations of in situ dissolved ioorganic nitrogen, phosphorus and silicon, as weIl as enrichment bioassays were llsed to dctcrrnine which nutrient (s) lirnited the potential biomass of phytoplankton. Both comparison of (NO.d-N02+NJ.L): P04 (DIN: DIP) values with Redfic1d's ratio and bioassay inspection led to the sarne conclusions. Phosphorus was clearly the nutrient most limiting for the potcntial biornass of test species in nitrogen- rich waters, which occurred in mid spring, in the upper layer of the southern-eastern part of the Gulf which is greatly influenced by river discharge. In late spring, with the decrease of the total DIN reserve, nitrogen and phosphorus showed an equallimiting role. In deeper layers of this area and out of the river plume (western side and central part of the gulf), nitrogen was the limiting nutrient. In summer, whcn river discharge was the lowest, a11 DIN concentrations but one ranged between 1.6 and 2.6 µM, and the whole area was nitrogen-limited for both the cyanobacterial and the algal test strains. In 74% of the samples for which nitrogen was the limiting nutrient, phosphorus was recorded to be the second potentially limiting nutrient. In contrast, silicon never appeared as limiting the growth potential of either Microcystis aeruginosa or Phaeodactylum tricornutum; phosphorus was the limiting nutrient when DIN: Si03 values were >1 (in May), but DIN: Si03 was <1 when nitrogen was limiting (June and July). The authors conclude that the recently reported decrease of silicon loading in coastal waters and its subsequent enhanced importance in pushing the outcome of species competition towards harmful species may not yet be the most important factor for the Gulf of Riga. Iron appeared for 12% of the tests in the list of nutrients limiting the potential biomass. Tentative results also indicated that a significant fraction of the nitrogen (~,4 µg-atom N 1(-1) taken up by Microcystis aeruginosa may have been in the form of dissolved organic nitrogen (DON). It is thus also suggested tentatively that more attention be paid to these nitrients during further research in the Gulf of Riga.

UNDERSTANDING LATE SEASON FRUIT ROT PATHOSYSTEMS AND INSECT INTERACTIONS IN MID-ATLANTIC VINEYARDS

Fungal fruit rots and insect pests are among the most important problems negatively affecting the yield and quality of mid-Atlantic wine. In pathogenicity trials of fungi recovered from diseased Chardonnay and Vidal blanc grapes, Alternaria alternata, Pestalotiopsis telopeae, and Aspergillus japonicus were found to be unreported fruit rot pathogens in the region. Additionally, P. telopeae and A. japonicus had comparable virulence to the region’s common fruit rot pathogens. Furthermore, a timed-exclusion field study was implemented to evaluate vineyard insect-fruit rot relationships. It was found that clusters exposed to early-season insect communities that included Paralobesia viteana had a significantly greater incidence of sour rot than clusters protected from insects all season. These results were contrary to the current assumption that fall insects are the primary drivers of sour rot in the region. This research provides diagnostic tools and information to develop management-strategies against fungal and insect pests for mid-Atlantic grape growers.

Tectonics of Central and Eastern California, Late Cretaceous to Modern

The Late Cretaceous to Modern tectonic evolution of central and eastern California has been studied for many decades, with published work generally focusing on specific geographic areas and time periods. The resulting literature leaves the reader, whether graduate student, faculty member, or layperson, wondering what a coherently integrated tectonic evolution might look like, or if it would be at all possible to undertake such a task. This question is the common thread weaving together the four studies presented in this work. Each of the individual chapters is targeted at a specific location and time period which I have identified as a critical yet missing link in piecing together a coherent regional tectonic story. In the first chapter, we re-discover a set of major west down normal faults running along the western slope of the southern Sierra, the western Sierra fault system (WSFS). We show that one of these faults was offset by roughly a kilometer in Eocene time, and that this activity directly resulted in the incision of much of the relief present in modern Kings Canyon. The second chapter is a basement landscape and thermochronometric study of the hanging wall of the WSFS. New data from this study area provide a significant westward expansion of basement thermochronometric data from the southern Sierra Nevada batholith. Thermal modeling results of these data provide critical new constraints on the early exhumation of the Sierra Nevada batholith, and in the context of the results from Chapter I, allow us to piece together a coherent chronology of tectonic forcings and landscape evolution for the southern Sierra Nevada. In the third chapter, I present a study of the surface rupture of the 1999 Hector Mine earthquake, a dextral strike slip event on a fault in the Eastern California Shear Zone (ECSZ). New constraints on the active tectonics in ECSZ will help future studies better resolve the enigmatic mismatch between geologic slip rates and geodetically determined regional rates. Chapter IV is a magnetostratigraphic pilot study of the Paleocene Goler Formation. This study provides strong evidence that continued investigation will yield new constraints on the depositional age of the only fossil-bearing Paleocene terrestrial deposit on the west coast of North America. Each of these studies aims to provide important new data at critical missing links in the tectonic evolution of central and eastern California.

An Analysis of the Early Prediction of Highway Construction Project Completion using the Contract Status Report

History has shown that projects move in and out of poor status through the life of the project. Predicting the success or failure of a project to complete on time because of its recent history on the contract status report could provide our project managers another tool for monitoring contract progress. In many instances, poor contract progress results in the loss of contract time and late completion of projects. This research evaluates the combinations of work type, point in time physical work begins, recent poor status, and contract bid amount as indicators of late project completion.

Provenance of upper Triassic sandstone, southwest Iberia (Alentejo and Algarve basins): tracing variability in the sources

Laser ablation ICP-MS U–Pb analyses have been conducted on detrital zircon of Upper Triassic sandstone from the Alentejo and Algarve basins in southwest Iberia. The predominance of Neoproterozoic, Devonian, Paleoproterozoic and Carboniferous detrital zircon ages confirms previous studies that indicate the locus of the sediment source of the late Triassic Alentejo Basin in the pre-Mesozoic basement of the South Portuguese and Ossa-Morena zones. Suitable sources for the Upper Triassic Algarve sandstone are the Upper Devonian–Lower Carboniferous of the South Portuguese Zone (Phyllite–Quartzite and Tercenas formations) and the Meguma Terrane (present-day in Nova Scotia). Spatial variations of the sediment sources of both Upper Triassic basins suggest a more complex history of drainage than previously documented involving other source rocks located outside present-day Iberia. The two Triassic basins were isolated from each other with the detrital transport being controlled by two independent drainage systems. This study is important for the reconstruction of the late Triassic paleogeography in a place where, later, the opening of the Central Atlantic Ocean took place separating Europe from North America.

Double trouble: French colonialism in Morocco and the early history of the Pasteur institutes of Tangier and Casablanca (1895-1932)

Morocco was the last North African country in which a Pasteur institute was created, nearly two decades later than in Tunisia and Algeria. In fact, two institutes were opened, the first in Tangier in 1913 and the second in Casablanca in 1932. This duplication, far from being a measure of success, was the material expression of the troubles Pastorians had experienced in getting a solid foothold in the country since the late 19th century. These problems partly derived from the pre-existence of a modest Spanish-Moroccan bacteriological tradition, developed since the late 1880s within the framework of the Sanitary Council and Hygiene Commission of Tangier, and partly from the uncoordinated nature of the initiatives launched from Paris and Algiers. Although a Pasteur Institute was finally established, with Paul Remlinger as director, the failure of France to impose its colonial rule over the whole country, symbolized by the establishment of an international regime in Tangier, resulted in the creation of a second centre in Casablanca. While elucidating many hitherto unclear facts about the entangled origins of both institutes, the author points to the solidity of the previously independent Moroccan state as a major factor behind the troubled translation of Pastorianism to Morocco. Systematically dismissed or downplayed by colonial and postcolonial historiography, this solidity disrupted the French takeover of the country and therefore Pastorian expectations.

TARDI VARISCAN DEFORMATION IN THE IBERIAN PENINSULA; A LATE FEATURE IN THE LAURASIA-GONDWANA DEXTRAL COLLISION

The Late Variscan deformation event in Iberia, is characterized by an intraplate deformation regime induced by the oblique collision between Laurentia and Gondwan. This episode in Iberia is characterized by NNE-SSW strike-slip faults, which are considered by the classic works as sinistral strike-slips. However, the absence of Mesozoic formations constraining the age of this sinistral kinematics, led some authors to consider it as the result of Alpine reworking. Structural studies in Almograve and Ponta Ruiva sectors (SW Portugal), not only shows that NNE-SSW faults presents a clear sinistral kinematics and are occasionally associated with E-W dextral shears, but also that this kinematics is related to the late deformation episodes of Variscan Orogeny. In Almograve sector, the late Variscan structures are characterized by NNE-SSW sinistral kink-bands, spatially associated with E-W dextral faults. These structures are contemporaneous and affect the previously deformed Carboniferous units. The Ponta Ruiva Sector constrains the age of deformation because the E-W dextral shears affect the Late Carboniferous (late Moscovian) units, but not the overlying Triassic series. The new exposed data shows that the NNE-SSW and the E-W faults are dynamically associated and results from the same deformation event. The NNE-SSW sinistral faults could be considered as second order dominoes structures related with first order E-W dextral shears, related with Laurasia-Gondwana collision during Late Carboniferous-Permian Times.

Lady Nugent and Tom Cringle on the veranda : early nineteenth century observations on a Caribbean architectural feature

This study of the veranda as seen through the eyes of Lady Maria Nugent and Michael Scott, alias Tom Cringle, clearly demonstrates the important role that the piazza, as it was then more commonly known, played in the life of early nineteenth century Caribbean colonial society. The popularity of the veranda throughout the region, in places influenced by different European as well as African cultures, and among all classes of people, suggests that the appeal of this typical feature was based on something more than architectural fashion. A place of relative comfort in hot weather, the veranda is also a space at the interface of indoors and outdoors which allows for a wide variety of uses, for solitary or small or large group activities, many of which were noted by Nugent and Scott. Quintessentially, the veranda is a place in which to relax and take pleasure, not least of which is the enjoyment of the prospect, be it a panoramic view, a peaceful garden or a lively street scene. Despite the great changes in the nature of society, in the Caribbean and in many other parts of the world, the veranda and related structures such as the balcony continue to play at least as important a role in daily life as they did two centuries ago. The veranda of today’s Californian or Australian bungalow, and the balcony of the apartment block in the residential area of the modern city are among the contemporary equivalents of the lower and upper piazzas of Lady Nugent’s and Tom Cringle’s day.