title: Tongatapu hardwater: Investigation into the ¹⁴C marine reservoir offset in lagoon, reef and open ocean environments of a limestone island

authors: Petchey, Fiona

subjects: radiocarbon

abstract: Although significant advances in our understanding of variation in the Pacific marine ¹⁴C reservoir have been made over the last ten years, our ability to obtain accurate calibrated ages for shellfish recovered from archaeological sites on Tongatapu remains problematic because of the influence of hardwaters on the central lagoon. Ultimately, this has implications for documenting the chronology of human movement and adaptation in this region. In this paper, we compare marine reservoir (∆R) data obtained from archaeological sites located along the lagoon and open coastline of Tongatapu, and use a combination of ∆R, δ¹⁸O and δ¹³C information to confirm a hardwater or open marine ¹⁴C signal in the shellfish. Despite documented changes to the lagoon as sea levels fell post-3000 years ago, these results indicate that there has been no noticeable change over time in the inner lagoon reservoir ¹⁴C value. Instead, variability in shellfish habitat and feeding modes is of greater concern to researchers using shell for dating, and requires further research

text: Tongatapu hardwater: Investigation into the ¹⁴C marine reservoir offset in lagoon, reef and open ocean environments of a limestone island Although significant advances in our understanding of variation in the Pacific marine ¹⁴C reservoir have been made over the last ten years, our ability to obtain accurate calibrated ages for shellfish recovered from archaeological sites on Tongatapu remains problematic because of the influence of hardwaters on the central lagoon. Ultimately, this has implications for documenting the chronology of human movement and adaptation in this region. In this paper, we compare marine reservoir (∆R) data obtained from archaeological sites located along the lagoon and open coastline of Tongatapu, and use a combination of ∆R, δ¹⁸O and δ¹³C information to confirm a hardwater or open marine ¹⁴C signal in the shellfish. Despite documented changes to the lagoon as sea levels fell post-3000 years ago, these results indicate that there has been no noticeable change over time in the inner lagoon reservoir ¹⁴C value. Instead, variability in shellfish habitat and feeding modes is of greater concern to researchers using shell for dating, and requires further research

year: 2011

title: On the role of pre and post-processing in environmental data mining

authors: Gibert, Karina

subjects: computer science

abstract: The quality of discovered knowledge is highly depending on data quality. Unfortunately real data use to contain noise, uncertainty, errors, redundancies or even irrelevant information. The more complex is the reality to be analyzed, the higher the risk of getting low quality data. Knowledge Discovery from Databases (KDD) offers a global framework to prepare data in the right form to perform correct analyses. On the other hand, the quality of decisions taken upon KDD results, depend not only on the quality of the results themselves, but on the capacity of the system to communicate those results in an understandable form. Environmental systems are particularly complex and environmental users particularly require clarity in their results. In this paper some details about how this can be achieved are provided. The role of the pre and post processing in the whole process of Knowledge Discovery in environmental systems is discussed.

text: On the role of pre and post-processing in environmental data mining The quality of discovered knowledge is highly depending on data quality. Unfortunately real data use to contain noise, uncertainty, errors, redundancies or even irrelevant information. The more complex is the reality to be analyzed, the higher the risk of getting low quality data. Knowledge Discovery from Databases (KDD) offers a global framework to prepare data in the right form to perform correct analyses. On the other hand, the quality of decisions taken upon KDD results, depend not only on the quality of the results themselves, but on the capacity of the system to communicate those results in an understandable form. Environmental systems are particularly complex and environmental users particularly require clarity in their results. In this paper some details about how this can be achieved are provided. The role of the pre and post processing in the whole process of Knowledge Discovery in environmental systems is discussed.

year: 2008

title: Artefacts, biology and bias in museum collection research

authors: Wehi, Priscilla M.

subjects: experimenta design

abstract: Museum collections are increasingly subjected to scientific scrutiny, including molecular, isotopic and trace-element analyses. Recent advances have extended analyses from natural history specimens to historical artefacts. We highlight three areas of concern that can influence interpretation of data derived from museum collections: sampling issues associated with museum collection use, methods of analysis, and the value of cross-referencing data with historical documents and data sets. We use a case study that focuses on kiwi (Apteryx spp.) feather samples from valuable 19th century Māori cloaks in New Zealand to show how sampling and analysis challenges need to be minimized by careful design. We argue that aligning historical records with scientific data generated from museum collections significantly improves data interpretation.

text: Artefacts, biology and bias in museum collection research Museum collections are increasingly subjected to scientific scrutiny, including molecular, isotopic and trace-element analyses. Recent advances have extended analyses from natural history specimens to historical artefacts. We highlight three areas of concern that can influence interpretation of data derived from museum collections: sampling issues associated with museum collection use, methods of analysis, and the value of cross-referencing data with historical documents and data sets. We use a case study that focuses on kiwi (Apteryx spp.) feather samples from valuable 19th century Māori cloaks in New Zealand to show how sampling and analysis challenges need to be minimized by careful design. We argue that aligning historical records with scientific data generated from museum collections significantly improves data interpretation.

year: 2012-07