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Reduced tillage (RT) has soil conservation benefits compared to conventional ploughing (Krauss et al., 2021), but can lead to lower yields in organic farming. For the further development of reduced tillage systems in organic farming a long-term experiment was established 2010 on a Loess soil in Aesch BL, Switzerland. The factors are tillage (plough vs. reduced) and fertilization (slurry vs. mineral fertilization on two levels each (1=low; 2=high) and no fertilization). The mean yield over 13 years was reduced by 4% with RT compared to ploughing (PL). Organic carbon stocks increased significantly in the surface layer (0–10 cm) in RT compared to PL, while in the 10–20 cm layer, they were not significantly lower (P≤0.01). Life Cycle Assessment (or simply LCA) revealed an 18 to 32% lower impact of RT on climate change, mainly due to more carbon being sequestered in the soil but also less energy use. Gross margins for RT vary depending on fertilizer treatment: with unfertilised and slurry1 they were similar to PL, with slurry2 they were 9% lower than with PL. Lower gross margins for RT were due to yield reductions and thus lower revenues. However, when subsidies for RT were considered, all RT treatments had a higher gross margin than the corresponding treatments with ploughing.

The preservation of organic and human remains in Early Nordic Bronze Age mounds (1700 BCE -1100 BCE) permits new provenance work on this important period. Studies have shown that different mobility/non-mobility patterns were exercised by elite women during this time. To extend the database, we conducted strontium isotope analyses of the enamel from the second and third molars from the elite female grave from Ginderup in Thisted County, Denmark. Among other items, this grave included the textile remains of a possible corded skirt or fringed blanket. We complemented analyses of this woman’s enamel with strontium isotope analyses of the first molar from Grave B as well as osteological analysis of the individuals from Early Nordic Bronze Age Graves A, B and C. Our results revealed that the strontium isotope ratios obtained from the woman wearing a possible corded skirt yielded one local ratio (M2) and one non-local ratio (M3). The results from Grave B yielded a ratio which falls within the local baseline of present-day Denmark. Our results suggest that the Ginderup Woman was probably of local origin, but that she also was repeatedly mobile during her life. These data are further evidence for the Nordic Bronze Age’s complex socio-dynamics.

Our study focused on the leaching processes in soil contaminated with hexavalent chromium (Cr(VI)), traced to industrial waste from a disused site and resulting in groundwater contamination. Mineral and geochemical characterization of the soil by means of XRD, SEM-EDS, total digestion and sequential extractions revealed that the main Cr content was from solid waste located in the upper meter of the soil profile. Flow-through and column experiments were carried out to investigate the processes responsible for Cr(VI) release. Cr(VI) mobility along the soil profile was also assessed. Moreover, Cr isotope signatures were used to evaluate a potential Cr(VI) reduction process, which preferably could immobilize toxic Cr(VI) complexes. One-dimensional (1D) numerical simulations reproduced the Cr(VI) release from the flow-through experiment containing the Cr(VI) rich-solid waste and also the Cr(VI) mobility along the column experiment. These results enabled us to interpret quantitatively the processes resulting in Cr(VI) contamination and mobility along the soil profile. Cr(VI) was released from dissolving Cr(VI)-rich phases (e.g., sodium chromate, Cr(VI)-hydrocalumite and Cr(VI)-ettringite) of the solid waste layer. Cr(VI) reduction and Cr(VI) adsorption did not take place along the column. Such accurate characterization of these processes is necessary for the mitigation of Cr(VI) mobility in contaminated soils.

Our study focused on the leaching processes in soil contaminated with hexavalent chromium (Cr(VI)), traced to industrial waste from a disused site and resulting in groundwater contamination. Mineral and geochemical characterization of the soil by means of XRD, SEM-EDS, total digestion and sequential extractions revealed that the main Cr content was from solid waste located in the upper meter of the soil profile. Flow-through and column experiments were carried out to investigate the processes responsible for Cr(VI) release. Cr(VI) mobility along the soil profile was also assessed. Moreover, Cr isotope signatures were used to evaluate a potential Cr(VI) reduction process, which preferably could immobilize toxic Cr(VI) complexes. One-dimensional (1D) numerical simulations reproduced the Cr(VI) release from the flow-through experiment containing the Cr(VI) rich-solid waste and also the Cr(VI) mobility along the column experiment. These results enabled us to interpret quantitatively the processes resulting in Cr(VI) contamination and mobility along the soil profile. Cr(VI) was released from dissolving Cr(VI)-rich phases (e.g., sodium chromate, Cr(VI)-hydrocalumite and Cr(VI)-ettringite) of the solid waste layer. Cr(VI) reduction and Cr(VI) adsorption did not take place along the column. Such accurate characterization of these processes is necessary for the mitigation of Cr(VI) mobility in contaminated soils.

87Sr/86Sr ratios have frequently been used for correlating marine sedimentary units and its fossils, especially where high fidelity reference curves exist. The latter are usually constructed from macrofossil calcite samples, which have been screened for post-depositional alteration. Here, belemnite rostra from Lower Jurassic (Upper Sinemurian–Upper Toarcian) siliciclastic and carbonate sediments of the Swabo-Franconian Basin, deposited at mid-latitudes in the Laurasian Seaway, were targeted to confirm the trends and absolute values of the marine 87Sr/86Sr reference curve throughout this interval. 87Sr/86Sr ratios are derived from 21 belemnite rostra from a wider set of fossil specimens for which preservation was controlled using Scanning Electron Microscopy (SEM) and element/Ca ratios. Taken together with published data, a compilation of >500 87Sr/86Sr data points is established that helps verifying the global significance of the reported trends and allows for the best-constrained reconstruction of marine 87Sr/86Sr across the late Sinemurian-Toarcian interval yet. The obtained results are in excellent agreement with earlier measurements from basins in Portugal, Spain, UK, Germany, and Bulgaria and Canada. 87Sr/86Sr ratios follow the well-known decreasing trend, from 0.70747 in the latest Sinemurian to lowest ratios of 0.70708 around the Pliensbachian–Toarcian boundary. Also the subsequent increase throughout the early Toarcian reaching values of >0.7072 in the early Late Toarcian is found to match previously established datasets. The new results further corroborate a link between marine 87Sr/86Sr ratios and rifting related to the Central Atlantic Magmatic Province throughout the Early Jurassic and increased radiogenic influx, possibly linked to Karoo-Ferrar volcanism and associated climate change in the Early Toarcian whic

Unique deposits that formed in the Precambrian oceans are the Banded Iron-Formations (BIFs) which are chemical sediments comprised of alternating layers of iron- and silica-dominated precipitates. The origin of this enigmatic banding is still debated, with most favoring a primary sedimentary and a few others arguing for a secondary diagenetic origin. We here use a high-resolution integrated multi-proxy approach and report on the Ge-Si-Fe and Th-U systematics and on the isotopic composition of Cr in exceptionally pure adjacent magnetite and metachert bands from the ∼2.7 billion years old Temagami BIF, Ontario, Canada. While each of the geochemical proxies alone may be controversial, our multi-proxy approach sheds new light on their applicability, as the two types of adjacent BIF bands are each characterised by a distinct geochemical signature. The magnetite bands show super-crustal (i.e. fractionated) Ge/Si ratios approaching those of modern marine high-temperature hydrothermal fluids, unfractionated Th/U ratios similar to those of crustal rocks, and unfractionated Cr isotope ratios similar to “Bulk Silicate Earth”. Adjacent metachert bands, however, show lower (i.e. unfractionated) Ge/Si ratios close to those of modern seawater, sub-crustal (i.e. fractionated) Th/U ratios, and fractionated Cr isotope ratios above those of Bulk Silicate Earth. The composition of the magnetite bands suggests that the original iron-oxyhydroxide precipitated during periods when the dissolved Ge, Th, U, and Cr inventory of ambient seawater was dominated by input from mafic crust via anoxic high-temperature hydrothermal fluids. In contrast, the composition of the metachert bands indicates that these formed during times when ambient seawater was dominated by low-temperature riverine input from an evolved landmass that despite its Neoarchean age had provided environments for oxidative Cr and U mobilization during terrestrial weathering. This suggests that habitats with oxygenic photosynt