Book Review: Space and Time Perspective in Northern St. Johns Archeology, Florida

A review of Goggin, John M.: Space and Time Perspective in Northern St. Johns Archeology, Florida Yale University Publications in Anthropology, No. 47, Yale University Press, New Haven. 1952. (147 pp., 12 plates, 8 text figures, one map, $2.00

Nineteenth annual New England Intercollegiate Geological Excursion: October 12 and 13, 1923, Massachusetts

Locality 1: Cut on Bow Street, south of Turkey Hill, northwest corner of Arlington; Locality 2: Blueberry Mountain, southeast border of Woburn between Woburn and East Woburn; Locality 3: Shore west of West Manchester, on Gloucester branch of the Boston and Maine R.R., third of the way from Beverly to Glouceste

Comparison of extent and transformation of South Africa’s woodland biome from two national databases

[From introduction] The recent completion of the South African National Land-Cover Database and the Vegetation Map of South Africa, Swaziland and Lesotho, allows for the first time a comparison to be made on a national scale between the current and potential distribution of ‘natural’ vegetation resources. This article compares the distribution and location of woodland-type vegetation categories defined within the National Land-Cover data and the equivalent ‘Savanna-thicket Biomes’ class defined within the Vegetation Mapdata. Significant differences were found, both in terms of the total areal extent, as well as the actual spatial distribution of these two data sets. These differences are a measure of the inherent mapping accuracies of each source, but rather an illustration of boundary delineation distinctions that are a result of different data sources, mapping objectives and information classes, that must be noted when comparing two essentially similar information sets

Planktonic foraminiferal depth habitat and δ18O calibrations : plankton tow results from the Atlantic sector of the Southern Ocean

Plankton tows conducted in the Atlantic sector of the Southern Ocean allow analysis of the influence of water column structure on planktonic foraminiferal abundance and δ18O composition. Foraminiferal abundance varies by several orders of magnitude across a large gradient in sea surface temperature and other hydrographic features, demonstrating high sensitivity of foraminiferal populations to regional differences in water properties. The depth of maximum abundance for key species such as Globigerina bulloides and Neogloboquadrina pachyderma is not constant from station to station. The pattern suggests that their abundance and shell chemistry are tied to density horizons or other conditions (such as food availability) that become more sharply defined with depth in the northern subantarctic. The consistent observation of Globorotalia inflata and Globoratalia truncatulinoides as relatively deep-dwelling species confirms their utility as indicators of upper thermocline properties. In δ18O all species are observed to be isotopically lighter than predicted from water properties, but the species-specific offset is fairly uniform at all stations. These observations define the utility of multispecies δ18O for reconstructing temperature and density stratification from past surface oceans

A proposed prioritization system for the management of invasive alien plants in South Africa

Every country has weed species whose presence conflicts in some way with human management objectives and needs. Resources for research and control are limited, so priority should be given to species that are the biggest problem. The prioritization system described in this article was designed to assess objectively research and control priorities of invasive alien plants at a national scale in South Africa. The evaluation consists of seventeen criteria, grouped into five modules, that assess invasiveness, spatial characteristics, potential impact, potential for control, and conflicts of interest for each plant species under consideration. Total prioritization scores, calculated from criterion and module scores, were used to assess a species' priority. Prioritization scores were calculated by combining independent assessments provided by several experts, thus increasing the reliability of the rankings. The total confidence score, a separate index, indicates the reliability and availability of data used to make an assessment. Candidate species for evaluation were identified and assessed by several experts using the prioritization system. The final ranking was made by combining two separate indices, the total prioritization score and the total confidence score. This approach integrates the plant's perceived priority with an index of data reliability. Of the 61 species assessed, those with the highest ranks (Lantana camara, Chromolaena odorata and Opuntia ficus-indica) had high prioritization and high confidence scores, and are thus of most concern. Those species with the lowest ranks, for example, Harrisia martinii, Opuntia spinulifera and Opuntia exaltata, had low prioritization scores and high confidence scores, and thus are of least concern. Our approach to ranking weeds offers several advantages over existing systems because it is designed for multiple assessors based on the Delphi decision-making technique, the criteria contribute equally to the total score, and the system can accommodate incomplete data on a species. Although the choice of criteria may be criticized and the system has certain limitations, it appears to have delivered credible results

Bostonia: The Boston University Alumni Magazine. Volume 9

Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs

Surface water temperature, salinity, and density changes in the northeast Atlantic during the last 45,000 years: Heinrich events, deep water formation, and climatic rebounds

We developed a new method to calculate sea surface salinities (SSS) and densities (SSD) from planktonic foraminiferal delta(18)O and sea surface temperatures (SST) as determined from planktonic foraminiferal species abundances. SST, SSS, and SSD records were calculated for the last 45,000 years for Biogeochemical Oceanic Flux Study (BOFS) cores 5K and 8K recovered from the northeast Atlantic. The strongest feature is the dramatic drop in all three parameters during the Heinrich ''ice-rafting'' events. We modelled the possibility of deepwater formation in the northeast Atlantic from the SSD records, by assuming that the surface waters at our sites cooled as they flowed further north. Comparison with modelled North Atlantic deepwater densities indicates that there could have been periods of deepwater formation between 45,000 and 30,000 C-14 years B.P. (interrupted by iceberg meltwater input of Heinrich event 3 and 4, at 27,000 and 38,000 C-14 years B.P.) and during the Holocene. No amount of cooling in the northeast Atlantic between 30,000 and 13,000 years could cause deep water to form, because of the low salinities resulting from the high meltwater inputs from icebergs. Our records indicate that after each Heinrich event there were periods of climatic rebound, with milder conditions persisting for up to 2000 years, as indicated by the presence of warmer and more saline water masses. After these warm periods conditions returned to average glacial levels. These short term cold and warm episodes in the northeast Atlantic ate superimposed on the general trend towards colder conditions of the Last Glacial Maximum (LGM). Heinrich event 1 appears to be unique as it occurs as insolation rose and was coeval with the initial melting of the Fennoscandian ice sheet. We propose that meltwater input of Heinrich event 1 significantly reduced North Atlantic Deep Water formation reducing the heat exchange between the low and high latitudes, thus delaying deglaciation by about 1500 radiocarbon years (2000 calendar years)

Millennial-scale sea surface temperature variability in the western tropical North Atlantic from planktonic foraminiferal census counts

Planktonic foraminiferal census counts are used to construct high-resolution sea surface temperature (SST) and subsurface (thermocline) temperature records at a core site in the Tobago Basin, Lesser Antilles. The record is used to document climatic variability at this tropical site in comparison to middle- and high-latitude sites and to test current concepts of cross-equatorial heat transports as a major player in interhemispheric climate variability. Temperatures are estimated using transfer function and modern analog techniques. Glacial-maximum cooling of 2.5°'3°C is indicated; maximum cooling by 4°C is inferred for isotope stage 3. The SST record displays millennial-scale variability with temperature jumps of up to 3°C and closely tracks the structure of ice-core Dansgaard/Oeschger cycles. SST variations in part of the record run opposite to the SST evolution at high northern latitude sites, pointing to thermohaline circulation and marine heat transport as an important factor driving SST in the tropical and high-latitude Atlantic, both on orbital and suborbital timescales