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With ever more inhibited programmes of excavation, new methods of site survey are always welcome. Here a soil geomorphologist joins forces with archaeologists to read the history of limestone blocks exposed on the surface at sites in southern Greece. Rillenkarren for example are vertical grooves caused by rainfall on stones that remained for long periods in the same place. These and other observations showed that what looked like clearance cairns had in fact been piled up in the Early Bronze Age and led in turn to the definition of a new type of settlement. Keywords: Greece, Early Bronze Age, fortifications, stone cairns, karst geomorphology, Introduction The investigation of two newly discovered fortified sites, Vayia and Vassa in southern Greece, contributes to a number of important issues in archaeology in general and Aegean prehistory in [...]

Daniel H. Sandweiss et al. (1) reiterate arguments advanced a decade ago (2) that climatic and oceanic changes 5000 years before present (B.P.) resulted in the onset of El Nino/Southern [...]

This greenhouse study evaluated nitrogen and sodium relations of three desert graminoids (Distichlis spicata, Leymus triticoides,andJuncus arcticus) as affected by availability of surface water, subsurface water or both. These species are amply distributed in desert wetlands of western USA where surface and subsurface water are differentially available. Plants of the three species were collected from two areas of ecological distribution: Bishop, California and Burns, Oregon. Because nitrogen and sodium uptake by plants is highly linked to water availability we established three general hypotheses for this study: (1) nitrogen uptake would be greater when plants have surface water available, (2) sodium uptake would be greater when plants do not have surface water available, and (3) there are populations’ differences in the response of the species to water availability. We grew plants in two-layer pots in which soil water content in the upper and lower layers was controlled independently. The first hypothesis was partially supported as onlyLeymus triticoidesseemed to preferentially depend on the top layer for nitrogen acquisition. With respect to the second hypothesis sodium concentration was indeed greatest when plants had no surface water, but only inD. spicata. The third hypothesis was also partially supported. The Oregon population ofJ. arcticushad 15% more nitrogen than the California population and the California population ofD. spicatahad 18% more sodium than the Oregon population. Our results underline the plant nutrient uptake implications of differential availability of water pools for common desert graminoid species. [ABSTRACT FROM AUTHOR]