Testing the capability of Rare Earth Elements to identify archaeological strata in an African site: The case of the terraced landscape at Konso, Ethiopia

Over the last twenty years Rare Earth Elements (REE) have started to be part of archaeometric studies. Due to their particular characteristics there have been several attempts to apply REE analysis to different archaeological scenarios including stratigraphically-controlled agricultural soils, demonstrating that this is an effective tool to understand how human activity is reflected in soil development. Our study proposes a new methodological approach for the identification of anthropogenic deposits through REE soil analysis, pushing current limitations of traditional chemical and sedimentology techniques. Our study represents the first application of REE concentrations in soils from tropical Africa within an archaeological context. The agricultural soils were captured in an artificial sediment trap that forms part of the terraced landscape in Konso, Ethiopia; a system thought to have developed over the last 500 years, and which was awarded World Heritage status in 2011. Forty samples were taken from successive alluvial layers down a c. 2m thick soil sequence that had accumulated behind a series of drystone walls. The samples were analyzed for trace elements and REE via ICP-MS. To understand the causes of enrichment or depletion of REE, the data were compared with soil organic matter, organic carbon and fire markers. To aid interpretation we crossreferenced our results with archaeobotanical and soil micromorphology data. Data were analysed using multivariate statistics. Taken together these results present a very different picture of landscape development to previous presented accounts; the REE analyses provide significant details regarding the source and transportation of sediments

Exploiting Externalities to Estimate the Long-Term Effects of Early Childhood Deworming.” Working paper

Abstract I investigate whether a large-scale deworming intervention aimed at primary school pupils in western Kenya had long-term effects on young children in the region, exploiting positive externalities from the program to estimate the impact on younger children who did not receive treatment directly. I find large cognitive effects-equivalent to half a year of schooling-for children who were less than one year old when their communities received mass deworming treatment. I also find modest positive effects on stature. Because mass deworming was administered through schools, I also estimate effects among children who were likely to have older siblings in school to receive the treatment directly; in this subpopulation, effects are twice as large

Exploiting Externalities to Estimate the Long-Term Effects of Early Childhood Deworming.” Working paper

Abstract I investigate whether a school-based deworming intervention in Kenya had long-term effects on young children in the region. I exploit positive externalities from the program to estimate impacts on younger children who were not directly treated. Ten years after the intervention, I find large cognitive effects-comparable to between 0.5 and 0.8 years of schooling-for children who were less than one year old when their communities received mass deworming treatment. Because treatment was administered through schools, I also estimate effects among children whose older siblings received the treatment directly; in this subpopulation, effects are nearly twice as large. (JEL: I10, O12, O15)