Soil distribution and soil properties in the subalpine region of Kazbegi; Greater Caucasus

Georgia Soils of the alpine ecosystem of Kazbegi region were investigated in an interdisciplinary project (founded by the Volkswagen Stiftung) from 2014 until 2017. Soils on sediment fans as well as glacial sediments, mostly Cambisols (Humic), are characterized by a low to moderate yield potential while high-yield soils, mostly Cambic Umbrisols, can be found on volcanic plateaus. A common element of all soils is the high humus content. Actually, most of them are used only for pasture, due to poor accessibility. Soils on fluvial deposits, mostly Fluvisols, show a very high range of Muencheberg Soil Quality Rating (M-SQR)-scores. Most limiting factors are climate as well as steepness, while the low nutrient supply and soil acidity can be tackled by adequate fertilization and liming practice. Inorganic or organic pollution were not detected. Altogether, the soils of the study area have the actually untapped potential to optimize the basic supply of the local population as well as tourism also by cultivation of cereals. Nevertheless, variety trials on different soil forming substrates as well as erosion control are major preconditions for successful implementation of new cropping systems in the Kazbegi region. Furthermore, particularly rare soils, e.g. Cambisols on Tephra, should be protected

Ongoing oversanding induces biological soil crust layering – A new approach for biological soil crust structure elucidation determined from high resolution penetration resistance data

© 2017 Elsevier B.V. The aim of this study was to determine the in-situ strength and microscopic characteristics of bio-physical micro-horizons in the top 40 mm of oversanded sand soils detected by depth dependent penetration resistance (PR). These micro-horizons result from the burial of biological soils crust (BSC) surfaces and contribute to soil stability. They are also important as the biotic source for seeding new surficial crusts. Ex-situ polarised optical micrograph was employed to determine the bio-physical structures associated with the fossil BSC horizons. An automated electronic micro penetrometer (EMP) determining in-situ depth dependent soil PR was used for the quantitative detection of surface and buried micro-horizons. PR data was modelled using a multi-component/soil and micro-horizon multilayer plastic shear stress model. This enabled determination of soil and sediment structure, the contribution of buried ‘fossil’ BSCs to soil strength and structural mapping. We also employed proxy (synthetic) layered soil systems to determine the effect of EMP shaft and probe tip shape upon the PR profile. This methodology represents a significant improvement over penetrometer methods that only use single-value surface breaking point information. We find that buried BSC structures can contribute over 80% of the soil strength even at ca. 20 mm depth and that the strength of a buried crust, at least in the medium term, can exceed that of (developing) surficial ones. Typical soil strengths of BSCs in the Negev desert, Israel lie between 1.5 and 3.6 MPa. Finally we discuss the effects and potential importance that buried BSC horizons may have upon heat, and the percolation and diffusion of moisture and gas through structured bio-physical, BSC capped sand soil systems

Effects of added sewage sludge on contamination with Cd by winter wheat (Triticum aestivum)

The accumulation and transfer of heavy metals along soil-plant at experimental field were investigated. The study was conducted in the north-east of Romania at the Ezăreni experimental farm of the University of Agricultural Sciences and Veterinary Medicine Iaşi, during 2007-2009, in a cropping systems, viz., rape - wheat (Brasica napus – Triticum aestivum). One of the objectives of the study was to determine the risk of soil and plants contamination with heavy metals on applied sewage sludge (SS) as less expensive organic fertilizer. For assess the effect of this fertilization were applied two doses of sewage sludge (20 t/ha and 30 t/ha). The results show that cadmium concentration increased with the increasing fertilization level. On the second year, the applied of 30 t/ha sewage sludge determinate a cadmium concentration greater than safely concentration for wheat plant

Non-standard neutrino interactions in IceCube

Non-standard neutrino interactions (NSI) may arise in various types of new physics. Their existence would change the potential that atmospheric neutrinos encounter when traversing Earth matter and hence alter their oscillation behavior. This imprint on coherent neutrino forward scattering can be probed using high-statistics neutrino experiments such as IceCube and its low-energy extension, DeepCore. Both provide extensive data samples that include all neutrino flavors, with oscillation baselines between tens of kilometers and the diameter of the Earth. DeepCore event energies reach from a few GeV up to the order of 100 GeV - which marks the lower threshold for higher energy IceCube atmospheric samples, ranging up to 10 TeV. In DeepCore data, the large sample size and energy range allow us to consider not only flavor-violating and flavor-nonuniversal NSI in the μ−τ sector, but also those involving electron flavor. The effective parameterization used in our analyses is independent of the underlying model and the new physics mass scale. In this way, competitive limits on several NSI parameters have been set in the past. The 8 years of data available now result in significantly improved sensitivities. This improvement stems not only from the increase in statistics but also from substantial improvement in the treatment of systematic uncertainties, background rejection and event reconstruction

IceCube Search for Earth-traversing ultra-high energy Neutrinos

The search for ultra-high energy neutrinos is more than half a century old. While the hunt for these neutrinos has led to major leaps in neutrino physics, including the detection of astrophysical neutrinos, neutrinos at the EeV energy scale remain undetected. Proposed strategies for the future have mostly been focused on direct detection of the first neutrino interaction, or the decay shower of the resulting charged particle. Here we present an analysis that uses, for the first time, an indirect detection strategy for EeV neutrinos. We focus on tau neutrinos that have traversed Earth, and show that they reach the IceCube detector, unabsorbed, at energies greater than 100 TeV for most trajectories. This opens up the search for ultra-high energy neutrinos to the entire sky. We use ten years of IceCube data to perform an analysis that looks for secondary neutrinos in the northern sky, and highlight the promise such a strategy can have in the next generation of experiments when combined with direct detection techniques