EURASIAN JOURNAL OF SOIL SCIENCE

89 – 94

Authors: Amrakh I. Mamedov

In arid and semi-arid zones with a short water resources studying the effects of water quality on soil water retention and structure is important for the development of effective soil and water conservation and management practices. Three water qualities (electrical conductivity, EC ~ 2, 100 and 500 μS cm-1 with a low SAR representing rain, canal-runoff and irrigation water respectively) and semi-arid loam and clay soils were tested to evaluate an effect of soil texture and water quality on water retention, and aggregate and structure stability using the high energy moisture characteristic (HEMC) method. The water retention curves obtained by the HEMC method were characterized by the modified van Genuchten (1980) model that provides (i) model parameters α and n, which represent the location (of the inflection point) and the steepness of the S-shaped water retention curve respectively, and (ii) a volume of drainable pores (VDP), which is an indicator for the quantity of water released by the tested sample over the range of suction studied, and modal suction (MS), which corresponds to the most frequent pore sizes, and soil structure index, SI =VDP/MS. Generally (i) treatments significantly affected the shape of the water retention curves (α and n) and (ii) contribution of soil type, water EC, and wetting rate and their interaction had considerable effect on the stability induces and model parameters. Most of changes due to the water quality and wetting condition were in the range of matric potential (ψ), 1.2-2.4; and 2.4-5.0 J kg-1 (pore size 125-250 μm and 60-125 μm). The VDP, SI and α increased, and MS and n decreased with the increase in clay content, water EC and the decrease in rate of aggregate wetting. The SI increased exponentially with the increase in VDP, and with the decrease in MS. Contribution of water EC on stability indices and model parameters was not linear and was soil dependent, and could be more valuable at medium water EC. Effect of wetting rate was more pronounced at low water EC. Results indicate that effectiveness of water EC in the field condition has no simple outcome on water retention and soil structure, and that its application should consider and be adjusted to soil properties and condition, such as soil texture, and moisture content and solution EC. Detailed contribution of treatments on structure induces and model parameters are discussed in the paper.

101 – 107

Authors: Betty Natalie Fitriatin, Anny Yuniarti, Tien Turmuktini, Fadilah Kennedy Ruswandi

Ultisol is soil that have problem of soil acidity, low organic matter and low available macro nutrient in particularly low P availability. This is only small part of phosphorus is available for plant because most of the phosphate was still present in the soil were fixed by soil colloids. Some soil microbes are known phosphate solubilizing microbes have capability to dissolve phosphate that transform of P fixed into the soluble P. The field experiment conducted at Jatinangor, West Java Indonesia to determine the effect of PSM on phosphate solubility, growth and yield of maize and phosphorus fertilizer efficiency. Design experiment of Randomized Block Design (RBD) was used in field experiment, consisted of two factors and three replications. Phosphate solubilizing microbe as the first factor consisted four levels i.e without, phosphate solubilizing bacteria (PSB), phosphate solubilizing fungi (PSF), mixture of PSB and PSF. While the second factor was P fertilizer consists five levels (0%, 25%, 50%, 75% and 100% doses of recomendation). The results of the field experiment showed that application of phosphate solubilizing microbes significantly improve the yield of maize in Ultisol Jatinangor, but did not significantly affect on soil P, available soil P, phosphatase and P uptake of plants. Application of a mixture of PSB and PSF better effect on soil available P and yield of maize. Phospate fertilizer dosing at a dose of 25 % , 50 % , 75 % and 100 % recommendations increased available soil P. Fertilizer of P could inhibit the activity of phosphatases. Phosphate fertilizer with dose 50 % recommendation gave better effect on soil P and yield of maize.

116 – 122

Authors: Ekaterina Ivanova, Natalia Chizhikova

Cyanobacteria and actinomycetes are essential components of soil microbial community and play an active role in ash elements leaching from minerals of the parent rock. Content and composition of clay minerals in soil determine the sorption properties of the soil horizons, water-holding capacity of the soil, stickiness, plasticity, etc. The transformative effect of cyanobacterial–actinomycetes associations on the structure of clay minerals – kaolinite, vermiculite, montmorillonite, biotite and muscovite – was observed, with the greatest structural lattice transformation revealed under the influence of association in comparison with monocultures of cyanobacterium and actinomycete. The range of the transformative effect depended both on the type of biota (component composition of association) and on the crystal–chemical parameters of the mineral itself (trioctahedral mica – biotite, was more prone to microbial degradation than the dioctahedral – muscovite). The formation of the swelling phase – the product of biotite transformation into the mica–vermicullite mixed-layered formation was revealed as a result of association cultivation. Crystal chemical transformation of vermiculite was accompanied by the removal of potassium (К), magnesium (Mg) and aluminum (Al) from the crystal lattice. The study of such prokaryotic communities existed even in the early stages of the Earth's history helps to understand the causes and nature of the transformations undergone by the atmosphere, hydrosphere and lithosphere of the planet.contribution of treatments on structure induces and model parameters are discussed in the paper.

131 – 137

Authors: Jordana Ninkov, Jovica Vasin, Stanko Milic, Petar Sekulic,Tijana Zeremski, Slobodan Milenkovic

This research studied the copper content of vineyard soils as affected by the long-term use of copper-based fungicides. The soil samples were taken from individual vineyards located in the central region of Serbia, from two depths: 0-30 and 30-60 cm. At the same time, at each site, control samples were collected from a nearby forest in order to determine the background concentrations. The pseudototal (CuT) and available (CuEDTA) copper content were analysed in 60 soil samples in total, 46 of which represented vineyard soils and 14 control samples. The maximum value of copper was 200.1 mg/kg of pseudototal and 82.1 mg/kg of available copper. Comparison of the copper content in vineyards to the background concentrations of control samples clearly confirmed anthropogenic influence. Out of 46 vineyard soil samples, about one half (22 of them) had the CuT concentration above the critical level of 60 mg/kg. Eleven samples had the pseudototal content over the MAC of 100 mg/kg. Anthropogenic influence was also confirmed on the basis of copper bioavailability and copper distribution along the soil profile. Available content of over 50 mg/kg was found in 8 out of 46 analysed samples of vineyard soils. According to the percentage contribution of available CuEDTA to pseudototalCuT, half of the samples were above 36%, which is potentially phytotoxic. The concentration of copper was the highest in the surface layer in the vineyard soil samples. A check of the background Cu levels has shown that the distribution of CuT and CuEDTA is uniform throughout the soil profile. Data from some of the analysed plots indicate that the process of erosion is under way at the site. The soil on lower-lying terrain has been found to be more exposed to copper pollution than the soil of higher terrain. Since copper at the surveyed sites is very persistent and accumulates in a short period of time, focus should be placed on the preventive measures of reducing the use of copper-based fungicides to an optimal level.

144 – 151

Authors: Tatiana Minkina, Saglara Mandzhieva, Galina Motusova, Marina Burachevskaya, Olga Nazarenko, Svetlana Sushkova, Rıdvan Kızılkaya

The emissions from the Novocherkassk power station comprise 1% of the total volume in the Russian Federation and up to 58% of the emissions in the Rostov oblast. The aim of this work was to assess the regularities of heavy metals accumulation and transformation in soils subjected to aerosol emissions from the power station on the basis of the fractional composition of their compounds. Studies have been conducted on the soils of monitoring plots distances from the power station (1.0–20.0 km) during 15 years. The monitoring plots located on fallow areas. Soil samples for the determination of soil properties and the contents of heavy metals compounds were taken from a depth of 0–20 cm. The soil cover in the region under study consisted of ordinary chernozems, meadow-chernozemic soils, and alluvial meadow soils. The total amount of heavy metals in soils was determined by X-ray fluorescence. Metals in soil extracts were determined by atomic absorption spectroscopy. The fractional composition of heavy metals was determined using combined fractionation. A combined approach for fractioning metal compounds in soils on the basis of and parallel extractions (1 N NH4Ac, pH 8; 1% EDTA in NH4Ac; and 1 N HCl) was used. Aerosol emissions from the power station are the major agents of technogenic impact on the soils under study in the Rostov oblast. The highest degree of contamination with metals (mg/kg: Ni - 64, Cd – 1.3, Cr - 145 and As – 12) was observed for soils located within a radius of 5 km from the power station along the predominant wind direction. It was marked the rise of metals mobility in the polluted soils and predominant participation of Cr and Ni organic-mineral complexes among their mobile species. The increasing of Cd mobility was provided predominantly by exchangeable forms and specifically sorbed by Fe-Mn (hydr)oxides. The environmental contamination hazard increases with the decreasing metal-buffering capacity of soils.