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Glavas, S., & Moschonas, N. (2002). Origin of observed acidic–alkaline rains in a wet-only precipitation study in a Mediterranean coastal site, Patras, Greece. Atmospheric Environment, 36(19), 3089–3099.
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Park, H., & Schlesinger, W. (2002). Global biochemical cycle of boron. Global Biogeochemical Cycles, 16, 1072.
Abstract: The global Boron (B) cycle is primarily driven by a large flux (1.44 Tg B/yr) through the atmosphere derived from seasalt aerosols. Other significant sources of atmospheric boron include emissions during the combustion of biomass (0.26-0.43 Tg B/yr) and coal, which adds 0.20 Tg B/yr as an anthropogenic contribution. These known inputs to the atmosphere cannot account for the boron removed from the atmosphere during rainfall (3.0 Tg B/yr) and estimated dry deposition (1.3-2.7 Tg B/yr). In addition to atmospheric deposition, rock weathering is a source of boron (0.19 Tg B/yr) for terrestrial ecosystems, and humans mine about 0.31 Tg B/yr from the Earth's crust. More than 4.8 Tg B/yr circulates in the biogeochemical cycle of land plants, and about 0.53-0.63 Tg B/yr is carried from land to sea by rivers. The biogeochemical cycle of boron in the sea includes 4.4 Tg B/yr circulating in the marine biosphere, and an annual loss of 0.47 Tg B/yr to the oceanic crust via a variety of sedimentary processes that collectively remove only a small fraction of the total annual inputs to the oceans. Thus with our current understanding of the global biogeochemistry of B, the atmospheric budget shows outputs > inputs, while the marine compartments show inputs > outputs. Despite these uncertainties, it is clear that the human perturbation of the global B cycle has more than doubled the mobilization of B from the crust and contributes significantly to the B transport in rivers.
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Gaye, C. B. (2001). Isotope techniques for monitoring groundwater salinization. Hydrogeology Journal, 9, 217–218.
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Schmittner, K. - E., & Giresse, P. (1999). The impact of atmospheric sodium on erodibility of clay in a coastal Mediterranean region. Environmental Geology, 37(3), 195–206.
Abstract: Heavy rainfalls, between 25 and 100 mm·h–1, were simulated on Pliocene/Quaternary sediments. To reproduce the heterogeneity of natural environments, 231 small plots of various sizes (between 2.5 and 3.5 m2; mean: about 3 m2) were used. The duration of all simulations was 1 h. We used water that had been collected during natural rainfall. The concentration of clay particles in the sheet wash depended upon the concentration of dissolved sodium in the wash (for about 42%) and of the sheet wash quantity (for about 37%). Under natural water conditions colloidal matter, like clay minerals, is charged negatively and therefore is destabilized by metal cations such as in the case of Na+. Results suggest that relatively higher concentrations of montmorrillonite were related to higher concentrations of sodium as opposed to illite and kaolinite. Microflakes of up to 25 μ were observed to vary between face-to-edge and face-to-face modes (competition between protons and other cations). The concentration of dissolved sodium (Na+) in the runoff water depends on water and sodium balances such as atmospheric input, infiltration, evaporation and surface water runoff. The reduction of vegetation cover increases the amount of salt and amorphous matter in/on the topsoil between heavy rainfall generations. The best predictor to explain montmorillonite, illite and kaolinite in % of mineral clay-sized matter in the surface water runoff (sheet wash) is the percentage of each clay mineral in the topsoil. As opposed to illite and kaolinite, more sheet wash indicate for montmorillonite relatively higher concentrations in the wash. The results of model simulations were confirmed on different field plots of about 1 ha and small catchments during natural heavy rainfall events. Models can also be used to understand and to better simulate sheet, rill and gully erosion, micropedimentation; and pedimentation.
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Vengosh, A., Spivack, A. J., Artzi, Y., & Ayalon, A. (1999). Geochemical and boron, strontium, and oxygen isotopic constraints on the origin of the salinity in groundwater from the Mediterranean coast of Israel. Water Resources Research, 35(6), 1877–1894.
Abstract: In order to identify the origin of the salinity and formation of saline plumes in the central part of the Mediterranean coastal aquifer of Israel, we determined the elemental and boron, strontium, and oxygen isotopic compositions of fresh and brackish groundwater (C1 up to 1500 mg/L). We distinguish between two key anthropogenic sources: (1) sewage effluents used for irrigation with high Na/C1, SO4/C1, and B/C1 ratios and low Br/C1 ratios relative to seawater ratios, low ;5•B values (0-10%o) and high ;5•80 values (>-4%0); and (2) imported water from the Sea of Galilee that is artificially
recharged tothe aquifer with high Br/C1 (3 x 10 -3) and ;5•80 values (-1%o) and a low 87Sr/86Sr ratio of 0.70753. The brackish groundwater from the saline plumes have relatively low Na/C1 ratios (0.5-0.8) and high Ca/Mg, Mg/C1, and Ca/(SO 4 q- HCO3) (> l) ratios relative to seawater ratios; marine SO4/C1 and Br/C1 ratios;5•B values of 24.8-49.9%0; 18 87 86 ;50 of -2.95%0 to -4.73%0; and Sr/ Sr ratios of 0.708275-0.708532. The composition of most of the investigated groundwater from the saline plumes differs from those of the 87 86 anthropogenic sources, imported water, fresh uncontaminated groundwater (Sr/ Sr of 0.70866, ;5•B of 20-30%o), and saline water from the adjacent Eocene aquitard. Only in ß 18 areas of artificial recharge does local groundwater have high Br/C1 and ;50 values that are typical to the Sea of Galilee. The linear relationships between chloride and most of the ions, including Band Sr, the relatively high ;5•B (>30%0) and low ;5•80 (<-4%0) values, and the chemical signature of the saline plumes (e.g., marine Br/C1 and SO4/C1 ratios), suggest that (1) mixing processes control the chemical composition of the brackish water within the aquifer, and (2) the saline postulated end-member has a chemical composition that resembles modified seawater with a marine and higher ;5•B values, and a 87Sr/86Sr ratio of <0.7083. We propose that most of the salinization phenomena and the formation of saline plumes in the inner parts of the coastal aquifer are derived from upconing of underlying natural saline water bodies and enhanced by overexploitation and draw-down of the overlying fresh groundwater.
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