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Soil organic carbon (SOC) is an important component of any soil which determines many of its properties. Nowadays, more and more attention is being paid to the SOC content determination in soils by not using the conventional, time-consuming and expensive technique, but by using colour image processing of soil samples. In this case, even the camera of modern smartphones can be used as an image source, making this technique very convenient and practical. However, it is important to maintain certain standardised conditions (light intensity, light incidence angle, etc.) when capturing the images of soil samples. In our opinion, it is best to use a regular scanner for this purpose, with subsequent image processing by graphic programs (e.g., Adobe Photoshop). To increase the reliability of the colour information obtained in this way, it is desired (if possible) to use a spectrograph or a monochromator in the subsequent calculation of reflection or brightness ratios. It is these two approaches that we have implemented in our work. As a result of the experiment, the values of brightness ratios (at 480, 650 and 750 nm wavelengths and integral brightness ratio), colour indicators (the hue, saturation and value [HSV], red, green and blue [RGB], CIE L*a*b* and cyan, magenta, yellow and key [CMYK] systems) and SOC content in Calcic Chernozem samples of the steppe zone of Ukraine were obtained. Using correlation analysis of the dataset, the existence of direct (r = 0.88–0.90) and inverse close relationships (r = −0.75–0.90) between SOC, values of brightness ratios and colour indicators of the soil samples were established. This allows us to develop predictive models. Statistical analysis showed that the models were significant when they were based on the values of brightness ratios at 650 nm wavelength, integral brightness ratio, V indicator in HSV system, R, G and B indicators in RGB system, C, M and K indicators in CMYK system and L* and b* indicators in L*a*b* system. The subsequent calculation of variation coefficients showed that the largest variability was observed in SOC indicators (CV = 0.72) and slightly less variability in the K index of CMYK system and brightness ratio values at 650 nm wavelength (CV = 0.67 and 0.53, respectively). Based on this, we believe that the models y = 0.0188 + 0.0535*x (x is the value of the K index in CMYK system) and y = 5.0716 – 3.2255*log10(x) (x is the value of brightness ratio at 650 nm wavelength) were the most statistically significant and promising parameters for determining SOC content (y in these equations) in Calcic Chernozem samples of the steppe zone of Ukraine.

Se analizan tecno-tipológicamente las industrias líticas, mayoritariamente elaborada sobre cuarcitas, del yacimiento paleolítico al aire libre de Tarazona III (2.479 piezas líticas), formando parte de la Secuencia Paleolítica del Guadalquivir, que abarca el final del Pleistoceno Medio e inicios del Pleistoceno Superior (129 ka y

espanolEl Plioceno Superior de la cuenca sedimentaria del Guadalquivir esta caracterizado por un episodio continental de caracter edafico con neoformacion de caolinitas. C. Viguier (1974) establecio el nivel guia en el perfil El Calvario (Olivares) en la plataforma de El Aljarafe (provincia de Sevilla, Espana). Se estudia fisico-quimica y mineralogicamente y se reinterpreta el perfil de tres metros de potencia, a partir de un muestreo sistematico cada 10-20 cm hasta el material parental y el significado del mismo en relacion al Plioceno Medio. Los resultados muestran una evolucion polifasica del perfil, con tres partes bien diferenciadas sedimentologicamente, formacion de caolinitas, intensa rubefaccion, incorporacion de carbonatos y procesos eolicos que lo hacen muy diferente del material parental. Los cambios en la distribucion de la fraccion arena modifican su porosidad y el movimiento de esmectitas, diferenciandose dos fases edafologicas imbricadas en los bloques sedimentarios existentes. EnglishThe Upper Pliocene of the Guadalquivir sedimentary basin is characterized by a continental episode of soil character with neoformation of kaolinites. Claude Viguier (1974) established the guide level in the profile El Calvario (Olivares) in the Aljarafe of the province of Seville (Spain). This three meter thick profile is physically and mineralogically studied and reinterpreted from a systematic sampling every 10-20 cm to the parent material and its meaning in relation to the Middle Pliocene. The results show a multiphasic evolution of the profile, with three sedimentological well differentiated parts, kaolinites formation, intense rubefaction, incorporation of carbonates and aeolian processes that make it very different from the parental material. Changes in the distribution of the sand fraction modify its porosity and the esmectites movement, differentiating two pedological phases imbricated in the existing sedimentary sectors.

International audience; The purpose of this study is to better understand the system of Quaternary loess-palaeosol sequences (LPS) of the Matmata region in southern Tunisia. Results from a combination of predominantly classical methods (grain size and mineral analysis, CaCO3- content estimation, environmental magnetism) indicate strong soil formation phases during which the conditions of sedimentation changed drastically. The heavy mineral analysis underlines northwest, west and southwest provenances of the loessic material. Furthermore, we discuss the process of soil formation in LPS and explain why these soils are very sandy in comparison to the loess units. During phases of soil formation, the northwestern sediment transport path was blocked while sandy material was blown dominantly from the southwestern Grand Erg. Therefore, we present a conceptual model including a provenance analysis of the loessic material that support and improve earlier results of Coudé-Gaussen and collaborators.; Dans cette étude, nous présentons un modèle conceptuel pour une meilleure compréhension du système de séquences de loess paléosol (LPS) dans la région de Matmata située dans le sud de la Tunisie. Les résultats d'une combinaison de méthodes principalement classiques (analyse granulométrique, analyse minéralogique, détermination de la teneur en CaCO3, magnétisme environnemental) indiquent des phases de formation importante de sols au cours desquelles les conditions de sédimentation ont fondamentalement changé. L'analyse des minéraux lourds met en évidence une origine nord-ouest, ouest et sud-ouest du matériel loessique. En outre, nous discutons la nature de la formation des sols et expliquons pourquoi ces sols sont si sableux par rapport aux unités de loess. Pendant les phases de formation des sols, le trajet des sédiments en provenance du nord-ouest a été bloqué alors que les matériaux sableux pouvaient encore être soufflés à partir du Grand Erg au sud-ouest. Notre modèle conceptuel de la provenance du lœss à Matmata soutient et précise les conclusions de Coudé-Gaussen et collaborateurs.

The appearances of palaeosurfaces intercalated into palaeo-dune fields on Fuerteventura are multifaceted. Although reddened layers in these dune sediments might suggest that strong soil-formation processes have taken place, the combination of aridity and parent material, namely biogenic carbonate sand of shelf origin, reveals that strong soil formation seems unlikely. These sediments rather represent de- and recalcification processes only. Solely in the case of admixed material of volcanic origin and dust deposits further soil-forming processes seem to be possible. Hematite-rich Saharan dust contributes to reddish colouration of the palaeosurfaces. In addition, CaCO3-coated iron particles appear to be ingredients of dust being leached after deposition and transformed to hematite. Overall, we propose much weaker soil-forming processes during the Pleistocene than previously postulated. Our findings support the relevance of local environments. Carbonate sands of shelf origin hinder strong soil formation and the reddish layers separating dune generations are palaeosurfaces, which mainly consist of Saharan dust. After deposition of allochthonous material, these layers are overprinted by weak soil-forming processes. The formation of palaeosurfaces primarily depends on morphodynamically stable periods during limited sand supply. Our data suggest a cyclicity of processes in the following order: (1) sand accumulation, (2) dust accumulation and weak soil formation, and (3) water-induced erosion. For the Canary Islands, we support the assumption of glacial maxima being periods of increased levels of moisture. In combination with rising sea level, we propose that favorable conditions of surface stability occur immediately after glacial maxima during periods of starting transgression, whereas regression periods immediately after sea-level high stands seem to yield the highest sand supply for the study area.

The development of the organic market in the world requires conducting a research on the problems that accompany this process. Such studies are becoming more popular and apply not only to organic products market at the global level, but also at the local level. In order to identify global problems, the state and trends of the organic products markets in the USA, Germany, France, Britain as the biggest national markets were analyzed on the basis of the data characterizing the state of organic products market in Ukraine and in the world, provided by the Research Institute of Organic Agriculture (FIBL) and the International Federation of Organic Agricultural Movements (IFOAM). The research of the state and trends of the Ukrainian organic market and agricultural production development was conducted, and using the SWOT analysis methodology and the principles laid out in the PEST analysis, its strengths and weaknesses, opportunities and threats were identified. Within each element, social, environmental, economic and financial constituents have been grouped, providing a possibility to understand which factor is determining in terms of sustainable development. It enabled to make a conclusion that the Ukrainian market remains small in size, entailing significant risks, first of all, for producers, as its further development requires a significant all-round support from the state both from the financial point of view and from the point of view of active promotion of sustainable development ideas and education of the population on the importance of consuming quality products, taking care about their health and, as a result, contributing to the improvement of the environment.

Donana temporary ponds (southwest Spain) form a system of water bodies of remarkable ecological singularity with a high protection status. However, its species composition, diversity, and distribution of algal communities are largely unknown. During a biological survey carried out in shallow temporary ponds in 2010, several unknown diatom taxa were found in various population densities in the epiphyton of these systems. Detailed light and scanning electron microscopy observations allowed the description of five of them (Eunotia vozmedianoi, Planothidium lacustre, Halamphora tharsis, G. undulans and Pinnularia acidophila var. baetica) as taxa new to science. Differential diagnostic criteria with respect to similar taxa, together with ecological and biogeographical implications of these findings, are briefly discussed. Our results support recent studies indicating that endemism in diatoms might be a widespread pattern.

A geoarchaeological study of some lithic assemblages found in late Middle Pleistocene and beginning Upper Pleistocene alluvial terraces system has been carried out. The MIS 6/MIS 5 transition in the fluvial terraces of the Guadalquivir River has been identified in the Middle Terraces Complex (MTC) at Tarazona (T11.1, +44–38 m and T11.2, +36–30 m) Seville (Spain). The results were obtained from an archaeological excavation (TAR-III), and two other complementary archaeological sites (TAR-I and TAR-II). Geomorphological cartography, chronostratigraphic study with OSL dating, cantometric analysis and technotypological characterization of 5870 lithic pieces (measurement techniques for erosion and transport on gravels and lithic) have been accomplished. The alluvial chronosequence shows a probable climatic character with autocyclic sedimentary processes correlated with the transition from MIS 6 to MIS 5. Four alluvial Episodes with associated lithic techno-complexes were identified, which refer to the chronostratigraphic transition from Mode 2 to Mode 3 during the late Middle Pleistocene (MIS 6) and the beginning of Upper Pleistocene (MIS 5): Episode 1 with Mode 2 (MIS 6); Episode 2 with varied assemblages that could be associated to Mode 2 or Mode 3 (129/121 ka, MIS 5e and MIS 5d, pre-110 ka); Episode 3 with Mode 3 (between 110 and 104 ka, MIS 5c), and Episode 4 with Mode 3 (post-MIS 5c). The archaeological sites have lithic pieces which were knapped in situ (workshop, habitual or temporary sites) or were slightly displaced. The raw material selection of high quality (quartzites from alluvial deposits) is very notable during Mode 2 (Acheulian) (TAR-I2), Mode 2 or Mode 3 assemblages (TAR-III5) and Mode 3 (TAR-III1, 2, 3). During Mode 3 (Middle Paleolithic) (TAR-II1), the selection of flint raw material was from areas near or in the Guadalquivir terraces.

Holocene and late Pleistocene alluvial sequences of the mid-Medjerda floodplain (Northern Tunisia) reveal three types of soils with gradual transitions: Fluvisols (Calcaric), Cambisols (Calcaric) and Calcic Luvisols (Chromic). Stratigraphic cross-correlations, palaeomagnetic secular variation, and 14 C and IRSL dating enable detailed information about ages and durations of soil formation in the floodplain. Weakly developed Fluvisols (Calcaric) commonly reveal late Holocene ages with soil formation durations lasting between 100 and 300 years. Hence, Holocene soil formation is detectable in the exposures from durations of around 100 years onwards. Cambisols show predominantly mid-Holocene ages. The durations of soil formation are between 800 and 5000 years. Calcic Luvisols (Chromic) feature late Pleistocene ages, with durations of soil formation between 10,000 and 40,000 years. Profile Development Indices were computed from simple field parameters like soil structure, soil colour, horizon thickness and leaching features. The derived development indices show good correlation ( R 2 = 0.804) with the calculated durations of soil formation. Field parameters are well suited for a quantitative development index of Holocene soil formation, even if very weak developed soils are predominant. The study shows that maturity stages of Holocene alluvial soils in a homogeneous Mediterranean environment are predominantly driven by soil formation duration.

The physicochemical properties of a red Mediterranean soil profile (Chromic Luvisol) developed on a fluvial terrace 20 m above the Guadalquivir river, near the city of Cordoba, Spain, were examined with emphasis on finding evidence of translocation of carbonates affecting preexisting Bt red horizons in the selected soil profile. The high concentration of carbonate nodules below the argillic horizon and the vertical distribution of carbonate supported the hypothesis that capillary ascent process explained this phenomenon. Two phases are suggested for this carbonation process. First, a Mediterranean pedo-genesis occurred, with illuviation, rubification, and lixivied carbonates, which are accumulated in deep calcic horizons with nodules more than 350 ky. This was followed by a second phase with important processes of capillarity ascent affecting preexisting Bt horizons and carbonate nodules with chronology dated 114 (8.9) ky.

The monolayer values at 30°C of 17 spices of various botanical families, obtained from different parts of the plant and commercially marketed in diverse forms, were determined from stepwise moisture adsorption data at four relative humidities over the lower 50% of water activity (a w) values by using the BET and GAB equations. Fitting was similarly good for five spices, better by the BET equation for five other spices, and better by the GAB equation for another three, the experimental results provided by the remaining four species being fitted by neither equation. The monolayer values determined by the three-parameter GAB model were not always larger than those obtained by use of the simpler two-parameter BET equation, which appears to be more accurate in those cases where only sorption data for the low a w range are available.

Se presenta una sintesis de las investigaciones morfoedafologicas elevadas a cabo en las formaciones superficiales del cuaternario continental de las cuencas sedimentarias (campinas) de Sevilla y Cordoba, con presencia de focos lagunares. A nivel geomorfologico resalta la presencia de una alta paleotopografia carbonatada, a partir de la cual se organiza el relieve actual y las catenas de suelos de fersialiticos a vertisoles. La tirsificacion, como mecanismo reciente, pero no actual, y diferenciada de un frecuente tenue ennegrecimiento de los horizontes, se detecta como proceso tipico en los perfiles edaficos de las formaciones lagunares permanentes y estacionales. Mientras que es constante y generalizada la incorporacion de sedimentos finos (arenas y limos) a los perfiles de las formaciones en posicion depresionaria. Con estos datos se interpreta la evolucion cuaternaria de las campinas, desde medios humedos lacustres-palustres a los actuales aridos o semiarldos, con geomorfologia lagunar proxima a tipos de sebkhas.