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The effect of alginit on the soil and on triticale was studied over three years, from 2012 to 2014, in a long-term field experiment set up on acidic sandy soil in Nyirlugos 53 years ago. A 100 t•ha-1 rate of alginit was applied in autumn 2011 on plots given 0, 50, 100 and 150 kg•ha-1•year-1 N. The originally 5 x 10 = 50 m2 plots were halved, and the halves without alginit treatment served as controls. The 4N + 4N (with alginit) = 8 treatments × 4 replications = 32 plots. The main results are as follows: 1. Physical soil measurements showed that alginit treatment had no effect on the total porosity or water capacity of the soil. The field capacity increased by 4.4% on average, but this was not significant. The saturation percentage (KA according to Arany) rose significantly from 30.2 to 31.6. 2. On alginit-treated plots the pH(KCl) increased from 3.9 to 6.2, CEC from 1.3 to 3.6, EC from 21 to 67 ms/cm and base saturation from 53% to 74%, while the hydrolytic acidity decreased from 10 to 6 after the first year. 3. NH4-acetate + EDTA-soluble Ca increased from 154 to 730, K2O from 50 to 62, Mg from 18 to 104, Sr from 0.9 to 4.4 mg•kg-1 and Ni from 125 to 330 μ g•kg-1 on the alginit-treated plots. 4. The straw and grain yield of triticale increased in all three years. Alginit treatment generally doubled the yields, especially on plots treated with 150 kg•ha-1•year-1 N, which became acidified and impoverished in Ca, Mg, K and P. 5. Alginit treatment increased the Mg, Mo and Cd uptake and reduced that of Mn, Zn and Ba by triticale seeds. The Ca, Mg, S and Mo concentrations increased in the straw, while the incorporation of Mn, Zn, Ba, Cu, Ni and Co was inhibited by alginit. 6. Alginit is a suitable mineral for the amelioration of similar acid sands, which may eliminate the acidity caused by excessive N supplies and improve the water holding capacity, colloidal and nutrient status and drought-tolerance, and thus their fertility.

A talajmikrobiota melyrehato vizsgalata elengedhetetlen a fenntarthato mezőgazdasagi termeles okologiai alapjainak a megteremtesehez. A mikrobialis kozossegek faji es funkcionalis diverzitasanak vizsgalatahoz a rendelkezesre allo hagyomanyos vizsgalati eljarasok mellett, szukseg van a talajbol tortenő DNS kinyeresen alapulo vizsgalati modszerek hazai agrarkutatasokba valo bevezetesere. A megfelelő modszertan kidolgozasanal figyelembe kell venni a talaj fizikai es kemiai tulajdonsagait, mert peldaul a talaj pH-erteke, humusztartalma, szemcseosszetetele alapvetően meghatarozza a talaj DNS kivonas sikeret. A sejtfeltaras modszeret vagy esetleg modszerkombinacioit a vizsgalni kivant mikrobacsoport(ok) anatomiai es elettani tulajdonsagaihoz kell igazitani. A DNS kivonas soran kompromisszumot kell talalni a kinyeresi hatekonysag es a tisztasag kozott. A kinyeresi hatekonysag novelese altalaban a tisztasag rovasara megy, vagy noveli a toredezettseget, ugyanakkor a tobbszoros tisztitasi procedura soran kevesebb, de nagy tisztasagu DNS nyerhető, de jelentős lehet az informaciovesztes is. A fenti irodalmi adatok alapjan a kulonboző modszereknek, vagy modszerkombinacioknak a kutatasi celhoz es az adott talaj-okologiai korulmenyekhez valo adaptalasat es fejleszteset tartjuk szuksegesnek.

A szójaoltás hatékonyságát és az oltóanyagtörzsek gazdanövény specificitását vizsgáltuk csernozjom talajon, szántóföldi körülmények között. A szóját (Glycine max L., Kurca) 80 kg vetőmag/5×1011 CFU arányban oltottuk. Az oltást a vegetációs periódus folyamán mikroelem tápoldattal egészítettük ki. Az eredményeket kezelésenként 5×1 folyóméter növény- és talajminta vizsgálata alapján értékeltük. A mikroszimbionta baktériumtörzsek összehasonlító jellemzését BOX-PCR módszerrel végeztük el. Megállapítottuk, hogy a vizsgált kontrollnövényeken nem volt gümőképződés. A szója magoltása sikeres volt. Az oltóanyagtörzsek infekciós- és N-kötő aktivitása megfelelő volt, növényenként átlagosan 6–7 összetett, aktív gümő képződött. Az oltás hatására a növények száraztömege 25%-kal nőtt. A kiegészítő mikroelem tápoldat nem növelte szignifikánsan a növények száraztömegét és virágszámát. Az oltóanyagban lévő törzsek közül csak egy volt képes hatékony szimbiózist kialakítani a szójával, ami a gazdanövény és mikroszimbionta közötti kapcsolat nagyfokú specificitására utal. Ezt a PCR vizsgálat eredményei is alátámasztották.

This paper introduces an in situ “Cyclodextrin-enhanced soil bioremediation technology” which is a combination of 1. in situ bioventilation for biodegradation in the unsaturated soil zone; 2. physico-chemical treatment of the pumped ground water; 3. impulsive flushing for the three-phase soil. For enhancement of biodegradation and solubilization randomly methylated β-cyclodextrin (RAMEB) was used. An additional aim of this study was to prove the importance of the technology monitoring which was used for characterisation of the soil processes by an integrated methodology. It consists of physico-chemical, biological and ecotoxicological methods specific for the contaminants. For technology monitoring the mobile soil phases – soil gas and ground water – were analysed. Sampling of the whole soil was carried out at the start and end of the technology application. RAMEB resulted in the enhanced removal of pollutants both from the saturated and unsaturated soil zones. Moreover, the biodegradation was more effective than the pump and treat technology, proved by the establishment of the carbon material balance in all soil phases.

This study concentrates on the effects of strong acid or alkaline treatments on subsequent titration curves of soil solid phase. Changes of soil mineral composition and organic matter content were estimated as a background. Samples of upper horizons of three brown, two chernozemic, one pseudopodzolic and three yellow-red soils were treated with hydrochloric acid or sodium hydroxide of concentrations ranging from 0.001 to 1 mol dm −3 . Sodium homoionic forms of the original and the treated soils were back titrated to estimate variable charge vs. pH dependencies and surface acidity. The total amount of variable charge decreased after acid and alkali treatments of low concentrations and increased at elevated concentrations. The latter phenomenon was particularly evident for alkali-treated clay-rich soils. In general, surface acidity weakened in acidic treatments and for clay-poor soils in alkaline treatments. The alkali treatment produced stronger surface acidity in clay-rich soils. In yellow-red soils, surface groups of apparent surface dissociation constants around 10 −4.5 were well distinguished. Amount of these groups decreased after acid treatment and sharply increased during alkali treatment. Marked increase of weakly acidic surface groups occurred after acid treatments. Long-term influence of pH on variable charge properties in natural soils can be similar to laboratory treatments, as evidenced by weaker surface acidity in soils of lower pH.

An HPLC method has been developed for determination of RAMEB in soil samplescontaminated with hydrocarbons. The extraction efficiency of RAMEB from soils wasfound to depend on the soil properties. The extraction method elaborated results in agood recovery from sandy and loamy soils, but only a poor recovery was obtained from soils of high clay content.

The limiting factor of soil remediation is often the low accessibility of the pollutants.Laboratory experiments have been carried out to investigate the effect of the randomlymethylated cyclodextrin (RAMEB) on bioremediation of various types of soils spikedwith Diesel and transformer oil and also on actual site soils contaminated with poorlydegradable mazout. The contaminated soil in the aerobic solid phase microcosm-experiments was amended with nutrients and supplemented with different amounts of RAMEB. An integrated chemical-biological-ecotoxicological methodology was applied to follow the bioremediation. The laboratory study proved the bioremediation enhancing effect of RAMEB both on artificially contaminated soils and on actual site mazout contaminated soils. RAMEB activated soil microbes by improving the bioavailability of the contaminants and accelerating biodegradation. Efficacy of RAMEB was influenced both by contaminantand environment related factors, such as the type and concentration of the pollutinghydrocarbons and characteristics of the soil.

Municipal waste landfills represent not only a source of landfill gases, but a source of thermal energy as well. The heat in landfills is generated by physical, chemical and microbiological processes. The goal of our study was to characterize the thermal properties of municipal solid waste (MSW) samples of the given landfill. A new apparatus was designed and constructed to measure heat flow. A systematic test series of 17 discrete measurements was carried out with municipal waste samples of 1.0-1.7 m(3). The thermal conductivity, heat diffusivity and specific heat capacity of the samples were determined. Analysing the results of the sampling and our experiments it was realized that the theoretical fundaments should be clarified. Two theories were developed for the serial and for the parallel heat flow in three phase disperse systems. The serial and parallel models resulted in different theoretical estimations. The measured thermal conductivity and heat diffusivity were better characterized by the parallel heat flow estimations. The results show that heat can flow parallel in solid, liquid and gas phases. Characterization of thermal properties serves to establish the fundament of heat extraction from municipal waste landfills.

Effects of 6 years no-tillage (NT), ploughing, disking and the two last treatments combined with loosening on surface area, water vapor adsorption energy, variable charge and fine pore properties of a brown forest soils were studied using water vapor adsorption–desorption, back-titration and mercury intrusion measurements. The studied soil properties altered markedly under mechanical tillage treatment as compared to NT soil. The radii and the volumes of cryptopores (sizes from 1 to a few tens of nanometers) decreased and the opposite was found for ultramicropores (sizes from a few tens of nanometers to around 10 μm). However, fractal dimension of cryptopores and ultramicropores had changed very slightly, indicating that general geometrical structure of the fine pore system in the studied range (ca 1 nm–10 μm) remained unaltered despite pore size-shift. Surface areas and the amount of variable surface charge were markedly lower in mechanically tilled soil. A decrease of organic matter content was observed as well. Decrease of water vapor adsorption energy and increase of the fraction of strongly acidic surface functional groups accompanied mechanical tillage treatments.

Ammonium salts used as fertilizers may cause soil acidification by two different processes: nitrification in soil and net release of protons from roots. Their influence on soil pH may vary depending on the distance from root surface. The aim of this study was to distinguish between these two processes. For this purpose rape seedlings were grown 10 d in a system which separated roots from soil by a fine-meshed screen. As a function of distance from the plane root layer formed on the screen, pH, titratable and exchangeable acidity and NO3- and NH4-nitrogen were determined. The soil, a luvisol from loess, was supplied with no N or (NH4)2SO4 either with or without a nitrification inhibitor (DCD). The bulk soil pH remained unaffected when no N or 400 mg NH4N kg−1 soil plus DCD was applied but it decreased from 6.6 to 5.8 without DCD. In contrast, rhizosphere pH decreased in all cases, mainly within a distance of 1 mm from the root plane only, but with gradients extending to between 2 and 4 mm into the soil. The strongest pH decrease, from 6.6 to 4.9, occurred at the root surface of plants treated with both NH4-N and DCD where most of the mineral N remained as ammonium. In this case Al was solubilized in the rhizosphere as indicated by exchangeable acidity. Total soil acidity produced in the NH4 treatment without DCD was mainly derived from nitrification compared to root released protons. However, acidification of the rhizosphere was diminished by nitrification because nitrate ions taken up by the roots counteracted net proton release. It is concluded that nitrification inhibitors may reduce proton input from ammonium fertilizers but enhance acidification at the soil-root interface which may cause Al toxicity to plants. Versauerung des Bodens und der Rhizosphare von Raps-Samlingen durch Nitrifikation und Ammoniumaufnahme Die Verwendung von Ammoniumsalzen als Dungemittel kann die Versauerung des Bodens durch zwei unterschiedliche Prozesse auslosen: Nitrifikation im Boden und netto-Abgabe von Protonen durch die Wurzeln. Ihr Einflus auf den Boden-pH-Wert hangt von der Entfernung zur Wurzel ab. Die Studie hatte das Ziel, die Wirkung dieser beiden Prozesse aufzugliedern. Dazu wurden Raps-Samlinge 10 d in einem System kultiviert, das die Wurzeln durch eine Gaze vom Boden trennt. Als Funktion des Abstands von der ebenen Wurzelschicht, die sich auf der Gaze bildete, wurden der pH-Wert, titrierbare und austauschbare Aziditat sowie die NH4- und NO3-Gehalte des Bodens, eines Luvisols aus Los, bestimmt. Der pH-Wert des wurzelfernen Bodens blieb in der Versuchszeit unbeeinflust, wenn kein N oder 400 mg N kg−1 mit einem Nitrifikationshemmstoff (DCD) eingemischt wurde, bei gleicher N-Gabe ohne DCD nahm er dagegen von pH 6,6 auf 5,8 ab. Der pH-Wert der Rhizosphare sank in alien Fallen ab und zwar vorwiegend im Bereich unter 1 mm Abstand von der Wurzelschicht, jedoch mit Gradienten, die zwischen 2 und 4 mm in den Boden hineinreichten. Die starkste pH-Absenkung, von pH 6,6 auf 4,9, trat an den Wurzeln von Pflanzen ein, die sowohl NH4-N als auch DCD erhalten hatten. Bei ihnen war der Hauptteil des Mineralstickstoffs in der NH4-Form verblieben. In diesem Falle trat auch gelostes Al in der Bodenlosung auf, wie an der Austauschaziditat zu erkennen war. Von der gesamten Aziditat stammte bei NH4-Dungung ohne DCD der Hauptteil aus der Nitrifikation und nur ein kleinerer Anteil aus der netto-Protonenabgabe der Wurzeln. Die Versauerung der Wurzeln wurde durch Nitrifikation verringert, weil die Nitrataufnahme der Wurzeln der Versauerung entgegenwirkte. Es wird der Schlus gezogen, das Nitrifikationshemmstoffe zwar den Protoneneintrag in den Boden mindern, das sie aber die Bodenversauerung an der Wurzel verstarken und so zu Al-Toxizitat an den Pflanzen fuhren konnen.

The aim of the current research is to establish a suitable Environmental Risk Assessment (ERA) scheme for Danube sediments in Hungary by determining contaminants' concentrations by chemical analysis and by assessing their ecotoxicological effects. Seventeen sedimentation sites were identified, mainly upstream of Budapest, between river kilometres 1811 and 1586. The heavy metal contents and basic properties of sediments were determined. Excess heavy metal content was used to characterize the extent of heavy metal contamination. Direct contact biotests were developed for testing the toxic effect of contaminated sediments. Ecotoxicological effects were measured by three bacterial tests and one plant bioassay. Effect Concentrations were determined by the inhibition of the bioluminescence of Photobacterium phosphoreum. The resultant inhibition of different partial toxic effects was characterized by Cu equivalent. Chemical and ecotoxicological results were studied together, making it possible to characterize the extent of the pollution and its biological effects at the same time. It was concluded that combined chemical and ecotoxicological characterization of contaminated sediments may serve as a strong basis for assessing the site-specific risk of heavy metal pollution.