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Abstract: High quality wood core samples were collected from individual Acacia erioloba trees of unknown age in the Kgalagadi Transfrontier Park. In the majority of samples examined, seasonal changes were reflected in the wood anatomy as bands of marginal parenchyma on the polished surfaces of discs or cores. Estimated radiocarbon age was determined by means of 14C analysis for all samples. There was a strong correlation between the annual growth ring count and estimated radiocarbon age. A correlation was also found between age and stem circumference. Age structure of several A. erioloba populations in the Kgalagadi Transfrontier Park was subsequently determined. It could be demonstrated that the populations growing in the bed of the Nossob River showed poor recruitment; however, no clear relationship was found between flooding and regeneration of A. erioloba in the riverbed. The population growing in the dune field had a healthy age structure. [Copyright &y& Elsevier]

Abstract: Radiocarbon analyses were used to determine the “biobased content” of a variety of diverse samples. The theoretical biobased contents of those samples were compared to the biobased content values obtained by radiocarbon analyses. Results of this work indicated that the radiocarbon analyses provided accurate (within ±3%, absolute) biobased content values for the samples tested. It is not practical to examine the accuracy of the radiocarbon analyses for every possible type of sample matrix. However, based on analyses performed on various types of samples, every indication is that the analyses provide accurate and reliable results on the biobased content of liquid and solid materials. [Copyright &y& Elsevier]

The soils of the Seabee Hook area of Cape Hallett in northern Victoria Land, Antarctica, were mapped and characterized. Seabee Hook is a low-lying gravel spit of beach deposits built up by coastal currents carrying basalt material from nearby cliffs. Seabee Hook is the location of an Adélie penguin (Pygoscelis adeliae) colony which influences the soils with additions of guano, dead birds, eggshells and feathers. A soil-landscape model was developed and a soil association was identified between the soils formed on mounds (relict beach ridges) favoured by penguins for nests (Typic Haplorthel) and the soils in the areas between the mounds (Typic Haplorthel/Typic Aquorthel). Soils formed on the mounds inhabited by penguins contained guano in the upper 50 cm, overlying sub-rounded beach-deposited gravel and sand. Soils between mounds had a thin veneer (< 5 cm) of guano overlying basaltic gravelly sand similar to that in the lower parts of the mound soils. The soils had high concentrations of nitrogen, organic carbon, phosphorus, cadmium, zinc, copper, and increased electrical conductivity, within horizons influenced by penguin guano. Five buried penguin bones were collected from the base of soil profiles and radiocarbon dated. The dates indicate that Seabee Hook has been colonized by penguins for at least 1000 years. [ABSTRACT FROM AUTHOR]

Abstract: In support of the USDA Federal Biobased Products Preferred Procurement Program (FB4P), Iowa State University is coordinating testing to determine the “biobased content” of manufactured products. These tests are part of a process to “designate” items that qualify for preferential procurement status with federal agencies. Biobased content determinations are being performed using three radiocarbon dating procedures specified in ASTM D 6866-05. Test results obtained thus far indicate that the AMS and benzene synthesis methods provide comparable results. Data from the CO2 cocktail method did not agree as well with the data from the other two methods, but were still in reasonably good agreement with those data. Radiocarbon analysis is shown to be a reliable and valuable tool for verifying the biobased content of a wide variety of biobased products. Based on inter- and intra-laboratory comparisons, a reasonable uncertainty to associate with the analyses would be ±3% (absolute) for the AMS and benzene synthesis methods. Because of limited data availability, additional work is needed to establish the uncertainty of the CO2 cocktail method for analyzing biobased products. [Copyright &y& Elsevier]