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Pedogenic carbonates from vadose soils form in areas of net water deficit, have δ 18 O values that are highly correlated with that of local meteoric water, and have been widely used as paleoclimate proxy records (Cerling and Quade, 1993). Paleo-climatic and paleohydrologic studies in humid continental settings, however, have been limited by the lack of(More)
High-precision uranium-thorium mass spectrometric chronology and (18)O-(13)C isotopic analysis of speleothem calcite from Cold Water Cave in northeast Iowa have been used to chart mid-Holocene climate change. Significant shifts in dagger(18)O and dagger(13)C isotopic values coincide with well-documented Holocene vegetation changes. Temperature estimates(More)
• We review current knowledge about the biology of the genus Acacia, and Acacia dealbata Link (silver wattle) in particular, as an invader in Europe, focusing on (i) the biology of the genus Acacia; (ii) biological attributes that are important for the invasiveness of the genus and A. dealbata; (iii) possible hypotheses for the invasion success; and (iv)(More)
We discuss a class of phase computer-generated holograms for the encoding of arbitrary scalar complex fields. We describe two holograms of this class that allow high quality reconstruction of the encoded field, even if they are implemented with a low-resolution pixelated phase modulator. In addition, we show that one of these holograms can be appropriately(More)
Allelopathy is often demonstrated by testing allelochemical effects on germination using many germination indices to assess them. The objective of this work was to compare four common germination indices (GT, S, AS, and CRG) previously calculated with the same data in order to discuss their physiological meaning. Each index led to a different interpretation(More)
This paper uses a multi-proxy approach involving pollen, plant macrofossils, speleothem isotopes, and alluvial history of streams to reconstruct the history of prairie expansion and contraction along the prairie-forest border of southeastern Minnesota, USA. Early Holocene forests were replaced by prairie along this border, but eastward expansion of prairie(More)
Siderite-bearing pedogenic horizons of the Nanushuk Formation of the North Slope, Alaska, provide a critical high paleo-latitude oxygen isotopic proxy record of pa-leoprecipitation, supplying important empirical data needed for paleoclimatic reconstructions and models of ''greenhouse-world'' precipitation rates. Siderite ␦ 18 O values were determined from(More)
a r t i c l e i n f o While the oxygen isotopic composition of pedogenic carbonate has successfully been used to address the effects of global climate change on the hydrologic cycle, detailed regional paleohydrologic studies are lacking. Since the hydrologic cycle can vary extensively on local or regional scales due to events such as such as mountain(More)