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Segregation and competition of Y-based impurities in Y-rich biepitaxial YBCO samples is investigated. The analysis of distribution and microstructure of the precipitates is performed by high resolution electron microscopy (HREM). Y 2 O 3 precipitates are found in (103) YBCO films grown on (110) SrTiO 3 (STO) substrates. On the same biepitaxial samples, Y 2 BaCuO 5 (Y211) precipitates are found in (001) YBCO films deposited on an intermediate (110) MgO seed layer. Agglomeration of Y211 precipitates is observed near the edge in the MgO seed layer. The experimental data are discussed in the context of phase competition, nucleation, epitaxy and surface migration in the Y–Ba–Cu–O system. It is deduced that the change of supersaturation and surface energy, also governed by the favorable epitaxy of the secondary phase with the substrate or the YBCO matrix, plays a major role in determining the segregation of either Y211 or Y 2 O 3 precipitates.

To assess the role of macrofauna-mediated sediment changes on nematode community recovery, we examined the temporal development of macrobenthos, nematode communities and sediment properties following hypoxia in 16 m2 replicated plots over a 6 mo period. Hypoxia drastically changed nematode community composition (i.e. reduced diversity and abundances of all dominant nematodes, except Odontophora spp.), but complete mortality, as was the case for the macrobenthos, did not occur. Macrofauna diversity recovered slowly, but community composition approached that of control communities after several months. In contrast, nematode diversity recovered to control values within 1 mo but, subsequently, decreased again; hence, no clear convergence towards the control community composition was apparent. This diversity decline and lack of community recovery was mainly attributed to abundance overshoots of the epistrate feeding nematodes Chromadora spp., Daptonema spp. and Ptycholaimellus ponticus in the treatments, which dominated the treatment community after 2 mo. Nematode community reassembling was strongly related to the coupled macrobenthos- environmental temporal development. The dynamics of 2 sediment characteristics, which were both mediated by the colonizing macrobenthos, are presented as possible determinant factors for this relationship: (1) low nematode post-settlement resuspension resulting from stable sediments at early macrofauna recovery stages and (2) enhanced nematode reproduction and settlement success in a dense microphytobenthos mat in relation to the temporal variation in macrobenthos grazing pressure and bioturbation. In conclusion, the strong relationships between macrobenthos recovery, environmental development and nematode community development after hypoxia highlight the importance of macrobenthos-sediment interactions in the recovery and structuring of nematode communities.

Contains fulltext : 69763.pdf (Publisher’s version ) (Closed access) Inhalation exposure to total and hexavalent chromium (TCr and HCr) was assessed by personal air sampling and biological monitoring in 53 welders and 20 references. Median inhalation exposure levels of TCr were 1.3, 6.0, and 5.4 microg/m(3) for welders of mild steel (MS, 5% alloys), and stainless steel (SS, >26% alloys), respectively. The median exposures to HCr compounds were 0.23, 0.20, and 0.08 microg/m(3), respectively. Median concentrations of TCr in urine, blood plasma and erythrocytes were elevated in all welders, compared with the corresponding median concentrations in the reference group (p

YBa2Cu3O7-x artificial grain boundary Josephson junctions have been fabricated, employing a recently implemented biepitaxial technique. The grain boundaries can be obtained by controlling the orientation of the MgO seed layer and are characterized by a misalignment of the c-axes (45 degrees a-axis tilt or 45 degrees a-axis twist). These types of grain boundaries are still mostly unexplored. We carried out a complete characterization of their transport properties and microstructure. Junctions and de SQUIDs associated with these grain boundaries exhibit an excellent Josephson phenomenology and high values of the ICRN product and of the magnetic flux-to-voltage transfer parameter respectively. Remarkable differences in the transport parameters of tilt and twist junctions have been observed, which can be of interest for several applications. A maximum speed of Josephson vortices as calculated from the voltage step values of the order of 2 x 10(6) m s(-1) is obtained. These devices could also have some impact on experiments designed to study the symmetry of the order parameter, exploiting their microstructure and anisotropic properties. High-resolution electron microscopy showed the presence of perfect basal plane faced boundaries in the cross sections of tilt boundaries.

We report on the preparation of CuBa(2)(Sr(x)Ca(1-x))(n)Cu(n-1)O(y) compounds by fabrication of (Ba,Sr,Ca)CuO(2) superlattices with pulsed laser deposition (PLD). A technique called interval deposition is used to suppress multi-level or island growth resulting in high-quality superlattice structures. Both, the applicability of PLD to atomic engineering as well as the fabrication of artificial superconductors is demonstrated. The (Sr,Ca)CuO(2)-BaCuO(2) superlattices are characterized by X-ray diffraction, high-resolution electron microscopy (HREM) and selected area electron diffraction. The superlattice period has been deduced from electron diffraction patterns and XRD measurements. For Sr containing films, the best growth behavior is observed and films with the highest degree of crystallinity are obtained, whereas superconductivity is only found in less crystalline, Ca containing films. Under some deposition conditions and depending on the amount of Ba containing layers in the superlattice, it was observed that the BaCuO(2) material is converted to Ba(2)CuO(4-delta). Image simulations to interpret the HREM contrast are performed. (C) 2001 Elsevier Science B.V. All rights reserved.

${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\delta}}}$ (YBCO) artificial grain-boundary Josephson junctions have been fabricated, employing a recently implemented biepitaxial technique. The grain boundaries can be obtained by controlling the orientation of the MgO seed layer and are characterized by a misalignment of the c axes (45\ifmmode^\circ\else\textdegree\fi{} c-axis tilt or 45\ifmmode^\circ\else\textdegree\fi{} c-axis twist). A detailed characterization of the Josephson properties has been carried out, showing remarkable differences in the transport parameters of tilt and twist junctions. High-resolution electron microscopy showed the presence of perfect basal plane faced boundaries in the cross sections of tilt boundaries; however interfaces meandering along the sample thickness are also sometimes observed. The correlation between transport properties and microstructure is investigated and the possibility to employ these junctions to explore the symmetry of the order parameter is presented. On the basis of the analysis of microstructural data and of a qualitative growth model for (103) YBCO grains, it is suggested that clean basal plane boundaries exhibiting uniform Josephson properties could be obtained by this technique.

a -axis oriented YBa 2 Cu 3 O 7− δ (YBCO) films on La 4− x Ba x Cu 5 O 13− δ (LBCO) template layers and multilayer structures with La 4− x Ba x Cu 5 O 13− δ as intermediate layer have been characterized by X-ray diffraction and high resolution electron microscopy. La 4− x Ba x Cu 5 O 13− δ as template layer induces a -axis growth of YBa 2 Cu 3 O 7− δ films with T c ( R = 0)= 81 K although the presence of c -axis domains at the interface is not entirely suppressed. Depending on the deposition temperature, this material can take the form of a disordered perovskite or exhibits a local ordering between the La and Ba cations of the type A 4 B. Moreover La 4− x Ba x Cu 5 O 13− δ can be used as a intermediate layer for SNS-type structures permitting the growth of a second YBCO layer in a -axis orientation.

Thin films of La{sub 2}SrCu{sub 2}O{sub 6+y} with varying Sr/La ratios have been grown by molecular beam epitaxy on (001) SrTiO{sub 3}; their structural as well as their transport properties are reported. Under appropriate conditions, thin films with a metal-like resistivity down to 8 K are obtained; i.e., these films are closer to the onset of superconductivity than previous results indicate for bulk samples. This observation might be explained by a thin-film-specific alteration in site occupation of the La and Sr atoms in the lattice. In addition, the defect structures of a typical sample have been studied by transmission electron microscopy and the thin-film/substrate interface structure is determined. Out-of-phase boundaries with displacement vectors R=[00(1)/(5)] occur throughout the entire film thickness. Such interfaces, which possibly originate at substrate surface steps, disconnect the CuO{sub 2} layers and negatively influence eventual superconductivity. The films contain copper oxide outgrowths and nano-sized a-axis grains at the surface. Locally a 2{radical}(2)a{sub p}{times}2{radical}(2)a{sub p} modulation is observed; we have determined its unit cell and compared it with other so-called 2{radical}(2)a{sub p}{times}2{radical}(2)a{sub p} structures occurring in other superconducting compounds such as YBa{sub 2}Cu{sub 3}O{sub 7{minus}d} and Bi{sub 1.8}Pb{sub 0.4}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+x}. {copyright} {ital 1997} {ital Themore » American Physical Society}« less

The report describes the amorphization occurring during mechanical grinding of a mixture of Bi-HTSC 2223 and 2212 phases. It is shown that the visually determined grain size and the actual crystal size diminish upon grinding. Noticeable amorphization occurs even after only 30 min of grinding. Furthermore, different crystal planes exhibit variable sensitivity towards the amorphization process and the high Tc-phase is more easily affected by this phenomenon than the low Tc-phase in the Bi-system. Identical results were obtained whether the starting composition of the spray dried powder was 2223 or 2234.

A combination of CeO 2 and PtO 2 doping has been studied in melt-processed YBa 2 Cu 3 O 7−x . This study was carried out using an optimized well established MTG process. The cerium-platinum doped samples exhibit a high fishtail effect with a J c of 4.3 × 10 4 A/cm 2 under an applied field of 1 T. Microstructural and nanostructural studies have been performed. The 211 and BaCeO 3 inclusions are a few micrometers wide and the formation of a metastable nanocrystalline phase (Y 4 Ba 4 )Cu 8− x (Ce,Pt) x O 20±σ related to the perovskite is detected. The 123 grains show no specific extended defect generated by the doping process. The relationship between structure and properties are discussed.

A layer of YBa2Cu3O7-delta (123) can be grown on a Y2BaCuO5 (211) substrate by reaction with a mixture of 3BaCuO(2) + 2CuO. This reaction has been studied in the temperature range of 930 to 980 degrees C. The reaction is never complete but levels off when the CuO present in the reactant mixture is exhausted, The liquid dissolves an excess of CuO and the 211 substrate becomes covered by co-precipitation of 123 grains and CuO inclusions. The formation of 124 and related polytypoids is favoured by the Cu-rich stoichiometry of the reactant liquid. The growth of the 123 grains follows a parabolic law. The presence of a thermal gradient during reaction does not affect the orientation of the grains but has an influence on the thickness of the 123 layer.

The microstructure of (001) YBa 2 Cu 3 O 7-δ and YBa 2 Cu 3-x M x O 7-δ (M = Zn or Fe) thin films grown by inverted cylindrical magnetron sputtering was investigated by means of electron microscopy. The imperfections present in the films are discussed. Special attention is paid to nanoscale Y 2 O 3 inclusions. The density of [001] Y 2 O 3 precipitates was studied in YBa 2 Cu 3-x Zn x O 7-δ and YBa 2 Cu 3-x Fe x O 7-δ thin films prepared under identical conditions. The density decreases for increasing Zn-content and is unaffected in case of Fe-substitution.

A method to correlate microstructure from cross-section transmission electron microscopy ~TEM! investigations and transport properties of a single well characterized high-Tc artificial grain boundary junction is reported. A YBa2Cu3O72d 45° twist junction exhibiting the typical phenomenology of high-Tc Josephson weak links was employed. The TEM sample preparation is based on focused ion beam etching and allows to easily localize the electron transparent area on a microbridge. The reported technique opens clear perspectives in the determination of the microstructural origin of variations in Josephson junction properties, such as the spread in Ic and IcRN values and the presence of different transport regimes in nominally identical junctions.

Segregation and competition of Y-based impurities in Y-rich biepitaxial YBCO samples is investigated. The analysis of distribution and microstructure of the precipitates is performed by high resolution electron microscopy HREM.. Y2O3 precipitates are found in 103. YBCO films grown on 110. SrTiO3 STO. substrates. On the same biepitaxial samples, Y2BaCuO5 Y211. precipitates are found in 001. YBCO films deposited on an intermediate 110. MgO seed layer. Agglomeration of Y211 precipitates is observed near the edge in the MgO seed layer. The experimental data are discussed in the context of phase competition, nucleation, epitaxy and surface migration in the Y–Ba–Cu–O system. It is deduced that the change of supersaturation and surface energy, also governed by the favorable epitaxy of the secondary phase with the substrate or the YBCO matrix, plays a major role in determining the segregation of either Y211 or Y2O3 precipitates

YBa(2)Cu(3)O(7-delta) (YBCO) grain boundaries characterized by a misalignment of the c-axes (45 degrees c-axis tilt or 45 degrees c-axis twist) have been obtained by employing a recently implemented biepitaxial technique. Junctions based on these grain boundaries exhibit good Josephson properties useful for applications. High values of the I(C)R(N) product and a Fraunhofer-like dependence of the critical current on the magnetic field, differently from traditional biepitaxial junctions, have been obtained. The correlation between transport properties and microstructure has been investigated by Transmission Electron Microscopy (TEM), which was also performed on previously measured junctions. The presence of atomically clean basal plane (BP) faced tilt boundaries, among other types of interfaces, has been shown. The possibility of selecting these kinds of boundaries by controlling film growth, and their possible advantages in terms of reproducibility and uniformity of the junction properties an discussed. The possibility of employing these junctions to explore the symmetry of the order parameter is also discussed.

A method to correlate microstructure from cross-section transmission electron microscopy (TEM) investigations and transport properties of a single well characterized high-T-c artificial grain boundary junction is reported. A YBa2Cu3O7-delta 45 degrees twist junction exhibiting the typical phenomenology of high T-c Josephson weak links was employed. The TEM sample preparation is based on focused ion beam etching and allows to easily localize the electron transparent area on a microbridge. The reported technique opens clear perspectives in the determination of the microstructural origin of variations in Josephson junction properties, such as the spread in I-c and IcRN values and the presence of different transport regimes in nominally identical junctions. (C) 1999 American Institute of Physics. [S0003-6951(99)03404-X].

The microstructure of various types of Josephson junctions is investigated with cross-sectional (CS) high-resolution electron microscopy (HREM). Special specimen preparation techniques, to facilitate the CS investigation, are discussed in the first part. Examples are shown of specially produced arrays of junctions and of the focused ion beam thinning technique allowing us to investigate specific measured junctions. Ramp-type junctions with PrBa2Cu3-xGaxO7-delta (PrBCGaO) barrier layers are discussed in more detail in the second part. The microstructure of PrBCGaO (0.1 < x < 1.0) thin films, barrier layers and bulk material is studied by HREM. Thin barrier layers with x greater than or equal to 0.7 contain a Ga-rich intergrowth, never observed before in YBCO-type structures. Ga-rich inclusions in single thin films exhibit a similar structure. In addition, diffusion of Ga in the ion-etched SrTiO3 substrate surface region was observed. The observed segregation of Ga from the PrBCGaO barrier layer explains the observed junction properties.

Nanoprecipitates in YBa2Cu3O7‐δ(YBCO) thin films have been identified by high resolution electron microscopy (HREM) as Y2O3 inclusions; they correspond to two different types of epitaxial relationships namely [001] or [110] parallel to the YBCOc‐axis. The [001] precipitates are situated near the YBCO surface, in the bulk and on the YBCO film/substrate interface. The [110] precipitates have only been observed at the surface. Literature data have been reinterpreted.

YBa(2)Cu(3)O(7-delta) (YBCO) grain boundaries characterized by a misalignment of the c-axes (45 degrees c-axis tilt or 45 degrees c-axis twist) have been obtained by employing a recently implemented biepitaxial technique. Junctions based on these grain boundaries exhibit good Josephson properties useful for applications. High values of the I(C)R(N) product and a Fraunhofer-like dependence of the critical current on the magnetic field, differently from traditional biepitaxial junctions, have been obtained. The correlation between transport properties and microstructure has been investigated by Transmission Electron Microscopy (TEM), which was also performed on previously measured junctions. The presence of atomically clean basal plane (BP) faced tilt boundaries, among other types of interfaces, has been shown. The possibility of selecting these kinds of boundaries by controlling film growth, and their possible advantages in terms of reproducibility and uniformity of the junction properties an discussed. The possibility of employing these junctions to explore the symmetry of the order parameter is also discussed. (C) 1999 Elsevier Science B.V. All rights reserved.

The physical properties and the microstructure of highly textured YBa2Cu3O7/Y2BaCuO5 ceramics, doped with platinum and/or cerium have been investigated by high resolution electron microscopy (HREM), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The Ce, Pt and Ce + Pt doped samples show different Jc behaviours as function of the applied field and a systematic comparison of the microstructure at different scales has been performed. The combination of both dopants leads to a drastic improvement of the critical current density either under zero field or with an external magnetic field (fishtail effect). A critical current density up to 56 000 A/cm2 has been observed, which remains 43 000 A/cm2 under 1 T in a sample doped with 2 wt% cerium oxide and 0.5 wt% platinum oxide. We suggest that a slight introduction of Ce in the YBa2Cu3O7−δ matrix locally changes the superconducting properties, and enhances the flux pinning properties. Micron size BaCeO3 particles, which appear with a preferential orientation in the YBa2Cu3O7−δ matrix, are also potential candidates for strong pinning. Other secondary phases, formed during the growth and the presence of a nanocrystalline phase in the plate like gap of the Ce + Pt doped samples are other admixtures. Finally a high density of twins is observed in all samples with some differences between the cerium and the platinum doped samples. They most probably contribute to pinning under intermediate field.

We studied the morphology of ramps in REBa2CU3O7 (REBCO) epitaxial films on SrTiO3 substrates, fabricated by RF magnetron sputter deposition and pulsed laser deposition (PLD), by scanning probe microscopy (SPM) and high resolution electron microscopy (HREM). The ramps were fabricated by Ar ion beam etching using masks of standard photoresist and TIN. AFM-studies on ramps in sputter deposited films show a strong dependence, i.e. formation of facets and ridges, on the angle of incidence of the ion beam with respect to the substrate surface as well as the rotation angle with respect to the crystal axes of the substrate. Ramps in pulsed laser deposited films did not show this dependence, Furthermore, we studied the effect of an anneal step prior to the deposition of barrier layers (i.e. PrBa2CU3O7, SrTiO3, CeO2) on the ramp. First results show a recrystallization of the ramp surface, resulting in terraces and a non-homogeneous growth of the barrier material on top of it. The thickness variations, for thin layers of barrier material, con even become much larger than expected from the amount of deposited material and are dependent on the deposition and anneal conditions. HREM studies show a well defined interface between barrier layer and electrodes. The angle of the ramp depends on the etch rate of the mask and REBCO, and on the angle of incidence of the ion beam. TiN has a much lower etch rate compared to photoresist, resulting in an angle of the ramp comparable to the angle of incidence, resulting in a low etching rate on the ramp. These results will lead to improved electrical characteristics of ramp-type junctions.

The use of a diluted O 2 /Ar atmosphere for laser deposition of YBa 2 Cu 3 O 7−x thin films results in a strong decrease of the surface outgrowth density as compared to deposition in pure O 2 . The smoother films need a longer oxygenation period and show slightly lower critical current densities, though still in excess of 10 6 A cm −2 at 77 K. Electron microscopy revealed that the outgrowths mainly consist of a large copper-oxide grain connected to Y 2 O 3 grains. Y 2 O 3 nano-scale inclusions are present irrespective of the deposition atmosphere, however, at remarkably low densities compared to other literature data. We find that the twin plane density is lower and the twin structure more homogeneous in the case of films deposited in a mixture of O 2 /Ar. This we ascribe to the absence of surface outgrowths which seem to block regular twin structure formation. Possibly the differences in necessary post deposition oxygenation time and in the electrical properties should be found in the difference in twin structure.

The dependence of the ramp geometry on high- or low-angle ion-beam etching, used to structure ramp-type Josephson junctions based on high- superconductors, is investigated by cross-section transmission electron microscopy. The surface quality, interfaces and crystal defects are analysed by high-resolution electron microscopy. Technical difficulties to reproducibly obtain the desired slope angle and shape make high-angle ion-beam etching less interesting although the surface quality is comparable and no systematic differences in electrical properties are observed.

Analytical and high resolution electron microscopy have been used to study the effect of Zn- and Fe-doping on the micro structure of [001] YBa 2 Cu 3 O 7-x thin films on [001] MgO substrates grown by magnetron sputtering. Special attention was paid to the presence of second phase inclusions and surface out-growths such as CuO, Y 2 Ba 1 Cu 1 O 5-x , Y 2 O 3 in order to establish a relationship with the critical current density.

A standard Philips CM200FEG electron microscope, without the special Lorentz lens, has been optimized for Lorentz imaging. The necessary field-free sample region is obtained by switching off the objective lens in the free lens mode. The limited range of magnification is compensated for by a post-column Gatan image filter (GIF) which magnifies by a factor of _ 20. Fresnel imaging is performed by defocusing with the diffraction lens. The use of low angle diffraction, in combination with the apertures located at the selected area aperture plane, allow Foucault imaging. The TEM analog of differential phase contrast (DPC) imaging has been implemented. This method makes it possible to obtain quantitave induction maps of the in-plane magnetization. TEM DPC is based on a series of Foucault images, recorded with different incremental beam tilts, which are processed to yield images equivalent to the quadrant signals obtained by the STEM DPC technique.

Ramp-type Josephson junctions with highly doped PrBa2Cu3-xGaxO7-δ barrier layers (x=0.7, 1.0) have been investigated by high-resolution electron microscopy. A Ga-rich intergrowth and Ga diffusion in the ion-milled SrTiO3 substrate are observed. The Ga segregation is responsible for the deviating electrical behavior as expected from extrapolation of low doping levels (x=0.1-0.4). The Ga diffusion in the ion-milled substrate, and possibly in the base electrode, may hamper Josephson junction fabrication using substituted REBa2Cu3O7-delta materials (RE=rare earth)

The structure of different intermediate layers and their interfaces was studied in sapphire bicrystals by high resolution electron microscopy (HREM), selected area electron diffraction (SAED) and energy dispersive X-ray analysis (EDX). The intermediate layer of Y3Al5O12 between two sapphire bicrystal parts, was found to be polycrystalline with three major orientations between sapphire and Y3Al5O12. The structure of the Y3Al5O12/sapphire interfaces is described. Sapphire bicrystals with a multilayer of Y-stabilized ZrO2 (YSZ) and sapphire (Al2O3) as intermediate layer, are also studied. Recrystallization of the intermediate layers occurred during the solid phase intergrowth of the sapphire bicrystals parts and only an YSZ layer was found as intermediate layer. The misorientation between the consecutive YSZ grains is less than 1.5°. Misfit dislocation and atomic height steps decorate the YSZ/sapphire interface.

Soil acidification can be detrimental to root growth and nutrient uptake, and liming may alleviate such acidification. In the following study, seedlings of sessile oak (Quercus petraea Liebl. M.) were grown in rhizotrons and subjected to liming (L) or gypsum (G) treatments and compared with the control (C). In order to study and interpret the impact of these calcium rich treatments on fine root development and tree growth, the following parameters were assessed: fine root biomass, fine root length, seedling development (height, diameter, leaves), seedling biomass, nutrient content of roots and seedlings, bulk soil and soil solution chemistry and rhizosphere soil chemistry. The results show that liming increased bulk soil pH, exchangeable Mg, Ca and the Ca/A1 molar ratio, and decreased exchangeable Al, mainly in the A-horizon. Gypsum had a similar but smaller impact on exchangeable Al, Ca, H+ and the Ca/Al molar ratio in the A-horizon, but reacted with depth, so that exchangeable Mn, Mg and Ca were increased in the B-horizon. In the rhizosphere, the general pattern was determined by the treatment effects of the bulk soil. Most elements were more concentrated in the rhizosphere than in bulk soil, except for Ca which was less concentrated after liming or gypsum application. In the B-horizon rhizosphere pH was increased by the treatments (L > G,C) close to the root tips. Furthermore, the length of the zone with a positive root-induced pH increase was greater for the limed roots as compared with both the other treatments. Fine root growth was stimulated by liming (L > G,C) both in terms of biomass and length, whereas specific root length was not obviously affected apart from the indication of some stimulation after liming at the beginning. The live:dead ratio of fine roots was significantly higher in the limed rhizotrons as compared to the control (G not assessed), indicating lower mortality (higher longevity). Shoot growth showed greater lime-induced stimulation (L > G,C) as compared to root growth. As a result the shoot:root ratio was higher in the limed rhizotrons than in the control (L > G,C). Liming induced a higher allocation of P, S, Mg, Ca and K to the leaves, stem and twigs. Gypsum showed similar effects, but was only significant for S. Liming increased the foliar Ca/A1 ratio by both increasing foliar Ca and decreasing foliar Al, whereas gypsum did not clearly improve foliar nutrition. This study suggests that a moderate application of lime can be successful in stimulating seedling growth, but that gypsum had no effect on seedling growth. It can be concluded that this lime-induced growth stimulation is directly related to the improved soil fertility status, and the alleviation of Al toxicity and acid stress, resulting in better foliar nutrition. The impact of liming on fine roots, as a consequence, was not limited to a stimulation of the total amount of fine roots, but also improved the root uptake performance.