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Restoring soil fertility and protecting it from pollution are complex scientific tasks of our time that require a set of physical, chemical and biological measures. An important theoretical and applied aspect is the development of new remediation methods to reduce soil degradation processes under the influence of chemical pollution. The publication analyzes the ecological features of the energy crops Miscanthus giganteus L. and Phalaris arundinacea L. as phytoremediation agents of soils contaminated with heavy metals, pesticides, and oil products. The content of toxicants in contaminated soils as a result of energy crops cultivation has significantly decreased, in particular, the content of mobile forms and the mass fraction of heavy metals. The greatest decrease was observed in the content of mobile forms of chromium: in the area contaminated with petroleum products by 0.55 mg/kg when growing reeds and by 1.06 mg/kg when growing miscanthus, and in the area contaminated with pesticides by 3.65 and 5.25 mg/kg, respectively. The gross stibium content decreased in the area contaminated with oil products by 60 mg/kg when growing reeds and by 69.61 mg/kg of soil when growing miscanthus, and by 65.68 and 78.35 mg/kg in the area contaminated with pesticides. The concentration of cadmium in the studied plots where energy crops were grown decreased in the range of 0.131-0.193 mg/kg when growing Phalaris arundinacea L. and by 0.187-0.312 mg/kg when growing Miscanthus giganteus L., respectively. The content of organic pollutants was also significantly reduced. [ABSTRACT FROM AUTHOR]

The article presents results of the research and mathematical modelling of the rainfall erosivity factors. Erosion, whether water, wind or resulting from soil cultivation, includes three processes -- soil descaling, movement and sedimentation. Spatial characteristics of precipitation during two researched periods are similar, having certain quantitative peculiar features. A common feature is maximum precipitation in the southwest and to a lesser extent in the eastern part of the region. Minimum precipitation is typical for the western part of the region. Peculiar feature of the second period of research is increase of contrasting effect of precipitation regime, when minimum values of precipitation decrease and maximum ones increase. Enhancement of contrasting effect of precipitation in space or time may cause increased intensity of erosion processes to the extent where the intensity of precipitation increases due to such contrasting effect. Thus, doubtless interest lies in the research of greater spatial or time contrasting effect of precipitation regime to activate water erosion. Thus, spatial peculiarities of distribution of precipitation within territory under study and time patterns correlate, but have their own special features. Clearly, total amount of precipitation as well as time distribution as a marker of correlation of intensification factor of erosion processes and defence mechanisms of vegetative cover are dominant for total losses of soil due to erosion. Coincidence of time of intense precipitation in summer and availability of vegetative cover reduces erosion. Nevertheless, continuance of intense precipitation when harvesting is started may cause intensification of water erosion of soil. Use of spatial variables and regression equations for spatial data calibration helped to estimate the spatial variation of precipitation on the territory under study. Comparison of two periods of research showed that in 2010-2016 significant reduction of rainfall erosivity factor has taken place in comparison with the previous period 9.6-65.4 MJ mm ha-1 h-1per year. In Turiyskyi and Kovelskyi district changes in rainfall erosivity factor were minimal (9.6 and 16.7 MJ mm ha-1 h-1per year respectively). Conversely, in Ivanytskyi and Gorokhivskyi districts changes were the most significant - 58.1 and 65.4 MJ mm ha-1 h-1per year respectively. [ABSTRACT FROM AUTHOR]

GPS observations of ocean tide loading displacements can help infer the regional anelastic properties of the asthenosphere. We estimate M2 ocean tide loading displacements at 170 GPS sites in New Zealand and compare these to modeled values using a range of numerical tide and radially symmetric (1D) elastic and anelastic Earth models. Regardless of the model combination, we are unable to reduce the strong spatial coherence of the M2 residuals across the North Island where they reach 0.4 mm (2%). The best fit in the North Island is obtained when combining the FES2014b tide model with spatially variable ocean density and water compressibility, and the STW105 Earth model. The residuals exhibit a change of ∼0.3 mm in magnitude between the Taupo Volcanic Zone and the east coast (∼100 km), suggesting that this region's laterally varying, shallow rheological structure may need to be considered to explain these observations. Plain Language Summary: The solid Earth changes shape due to the changing weight of the ocean as the ocean tides rise and fall. Measuring this change and comparing it to predictions can yield insights into the interior properties of the Earth, tens to hundreds of kilometers below the surface. We used GPS to measure the changing shape of New Zealand and compared it with predictions based on a range of Earth and tide models. The difference between the observed and modeled displacements revealed a complicated pattern over New Zealand, especially in the North Island and specifically near the Taupo Volcanic Zone. Due to the high accuracy of our GPS analysis and the ocean tide models, the observed residuals provide information about the elastic properties of the Earth and the complex geological structure of the region. The observed significant misfits show limitations of the 1D Earth model that varies only with depth which is standard in geodetic analysis. Key Points: M2 ocean tide loading displacements in New Zealand are inferred from GPS observationsEstimates for the North Island are not reproduced by models combining ocean tide loading and a 1D (an)elastic Earth structureSpatially coherent residual displacements of ∼0.4 mm (2%) are likely due to lateral Earth structure associated with Pacific Plate subduction [ABSTRACT FROM AUTHOR]

Ground displacements due to ocean tide loading have previously been successfully observed using Global Positioning System (GPS) data, and such estimates for the principal lunar M2 constituent have been used to infer the rheology and structure of the asthenosphere. The GPS orbital repeat period is close to that of several other major tidal constituents (K1 , K2 , S2); thus, GPS estimates of ground displacement at these frequencies are subject to GPS systematic errors. We assess the addition of GLONASS (GLObal NAvigation Satellite System) to increase the accuracy and reliability of eight major ocean tide loading constituents: four semi-diurnal (M2 , S2 , N2 , K2) and four diurnal constituents (K1 , O1 , P1 , Q1). We revisit a previous GPS study, focusing on 21 sites in the UK and western Europe, expanding it with an assessment of GLONASS and GPS+GLONASS estimates. In the region, both GPS and GLONASS data have been abundant since 2010.0. We therefore focus on the period 2010.0–2014.0, a span considered long enough to reliably estimate the major constituents. Data were processed with a kinematic precise point positioning (PPP) strategy to produce site coordinate time series for each of three different modes: GPS, GLONASS and GPS+GLONASS. The GPS solution with ambiguities resolved was used as a baseline for performance assessment of the additional modes. GPS+GLONASS shows very close agreement with ambiguity resolved GPS for lunar constituents (M2 , N2 , O1 , Q1) but with substantial differences for solar-related constituents (S2 , K2 , K1 , P1), with solutions including GLONASS being generally closer to model estimates. While no single constellation mode performs best for all constituents and components, we propose to use a combination of constellation modes to recover tidal parameters: GPS+GLONASS for most constituents, except for K2 and K1 where GLONASS (north and up) and GPS with ambiguities resolved (east) perform best. [ABSTRACT FROM AUTHOR]