from New Scientist
The nitrogen the Vikings left behind
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A belated news item on a novel way of detecting buried archaeological sites without digging! By looking at the proportion of nitrogen isotopes in uncultivated plants growing above ground, scientists have recently discovered that the normal nitrogen isotope ratio would be different for those plants growing immediately above the archaeological sites being studied. This could be due to human and/or animal waste products accumulated before the sites were buried. Yet another useful tool in the search for past heritage sites, perhaps.