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Joseph, J., Külls, C., Arend, M., Schaub, M., Hagedorn, F., Gessler, A., et al. (2019). Application of a laser-based spectrometer for continuous in situ measurements of stable isotopes of soil CO2 in calcareous and acidic soils. Soil, 5(1), 49–62.
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Illgen, M., & Ackermann, H. (2019). In S. Köster, M. Reese, & J. ’e Zuo (Eds.), Urban Flood Prevention: Technical and Institutional Aspects from Chinese and German Perspective (pp. 173–193). Cham: Springer International Publishing.
Abstract: Today’s cities face the challenge of climate change adaptation worldwide. In this context, prevention of damage caused by flash floods plays an important role. This requires a cooperative pluvial flood risk management approach, which includes planning, technical, and administrative measures and involves preliminary flood risk analyses. This article outlines the main components of this risk management approach, which has proven its effectiveness in Europe. The recommendations formulated for this purpose are applicable or adaptable to regions with other constraints, such as China, for example.
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Rosen, M. R., Burow, K. R., & Fram, M. S. (2019). Anthropogenic and geologic causes of anomalously high uranium concentrations in groundwater used for drinking water supply in the southeastern San Joaquin Valley, CA. Journal of Hydrology, 577, 124009.
Abstract: Concentrations of uranium (U) \textgreater30 µg/L in groundwater are relatively uncommon in drinking water in the United States but can be of concern in those areas where complex interactions of aquifer materials and anthropogenic alterations of the natural flow regime mobilize U. High concentrations (\textgreater30 µg/L) of U in the southeastern San Joaquin Valley, California, USA, have been detected in 24 percent of 257 domestic, irrigation, and public-supply wells sampled across an approximately 110,000 km2 area. In this study we evaluated mechanisms for mobilization of U in the San Joaquin Valley proposed in previous studies, confirming mobilization by HCO3 and refuting mobilization by NO3 and we refined our understanding of the geologic sources of U to the scale of individual alluvial fans. The location of high concentrations depends on the interactions of geological U sources from fluvial fans that originate in the Sierra Nevada to the east and seepage of irrigation water that contains high concentrations of HCO3 that leaches U from the sediments. In addition, interactions with PO4 from fertilized irrigated fields may sequester U in the aquifer. Principal component analysis of the data demonstrates that HCO3 and ions associated with high total dissolved solids in the aquifer and the percentage of agriculture near the well sampled are associated with high U concentrations. Nitrate concentrations do not appear to control release of U to the aquifer. Age dating of the groundwater and generally increasing U concentrations of the past 25 years in resampled wells where irrigation is prevalent suggests that high U concentrations are associated with younger water, indicating that irrigation of fields over the past 100 years has significantly contributed to increasing concentrations and mobilizing U. In some places, the groundwater is supersaturated with uranyl-containing minerals, as would be expected in roll front deposits. In general, the interaction of natural geological sources high in U, the anthropogenically driven addition of HCO3 and possibly phosphate fertilizer, control the location and concentration of U in each individual fluvial fan, but the addition of nitrate in fertilizer does not appear control the location of high U. These geochemical interactions are complex but can be used to determine controls on anomalously high U in alluvial aquifers.
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Karaimeh, S. A. (2019). Maintaining desert cultivation: Roman, Byzantine, and Early Islamic water-strategies at Udhruh region, Jordan. Journal of Arid Environments, 166, 108–115.
Abstract: The site of Udhruh is located in the arid desert of southern Jordan, about 15 km to the east of Petra. The site was built by the Nabataeans but expanded by the Romans (as a defensive site) and was continuously occupied until the Early Islamic period. It receives less than the 200 mm of annual precipitation, which is crucial for agricultural cultivation. Archaeological evidence from earlier excavations together with new data from several survey projects indicate that areas around Udhruh were cultivated throughout the Roman, Byzantine, and Early Islamic periods (300 BCE–800 CE). The fundamental question is: how did the people of Udhruh sustain their community in the desert, and how did they transform the desert into arable land? The landscape could be utilised thanks to sophisticated water management and irrigation techniques. At least four underground qanat systems were identified providing Udhruh with access to groundwater. At the terminal end of the qanat systems, several types of closed surface channels conveyed the water to reservoirs, which subsequently distributed the water to the field systems. The water systems of Udhruh differ from the well-known Nabataean systems in the surrounding area. As Udhruh was taken over by the Roman army in 106 CE, this study analyses how the Nabataean water systems continued to function and adapt through the Roman and Byzantine periods. A complete understanding of Udhruh’s water systems helps to reconstruct past land use, agricultural activity, and irrigation practices in a currently arid region.
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Hall, S. M., Gosen, B. S. V., Paces, J. B., Zielinski, R. A., & Breit, G. N. (2019). Calcrete uranium deposits in the Southern High Plains, USA. Ore Geology Reviews, 109, 50–78.
Abstract: The Southern High Plains (SHP) is a new and emerging U.S. uranium province. Here, uranyl vanadates form deposits in Pliocene to Pleistocene sandstone, dolomite, and limestone. Fifteen calcrete uranium occurrences are identified; two of these, the Buzzard Draw and Sulfur Springs Draw deposits, have combined in-place resources estimated at about 4 million pounds of U3O8. Ore minerals carnotite and finchite are hosted in dolomite at the Sulfur Springs Draw deposit, with accessory fluorite, celestine, smectite/illite, autunite, and strontium carbonate. Host carbonate at the Sulfur Springs Draw deposit is ∼190 ka and mineralization mobilized as recently as 3.8 ka. Ash collected near the deposit is 631 ka and erupted from the Yellowstone caldera complex. The Triassic Dockum Group that contains sandstone-hosted uranium deposits throughout the region and underlies the SHP is a potential source for uranium and vanadium. Regional uplift and dissection reintroduced oxygenated groundwater into the Dockum Group, mobilizing uranium. Additional uranium may have been contributed to groundwater by weathering of volcanic ash in Pliocene and Pleistocene host rocks. The locations of the uranium occurrences are mostly in modern drainage systems in the southeast portion of the SHP. Modelling of modern groundwater in the SHP carried out in a parallel study shows that a single fluid could form carnotite through evaporation, and that fluids of the requisite composition are more prevalent in the southern portion of the SHP. The southeastern portion of the SHP hosts more uranium occurrences due to a variety of factors including (1) upward transport of groundwater and connectivity between source and host rock, (2) higher uranium and vanadium content of groundwater, (3) higher rates of groundwater recharge in this region to drive the mineralizing system, and (4) shallower groundwater facilitating surface evaporation. Ongoing erosion of host rocks challenges preservation of deposits and may limit their size.
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