Alluvial fans formed from sediments derived from erosion of the Juarez Mountains in northernmost Mexico have a significant flood impact on the Ciudad Juarez, which is built on the fan system. The northern part of Ciudad Juarez is the most active; further south, older parts of the fan, upon which the rest of the city is built, were largely eroded by natural processes prior to human habitation and subsequently modified only recently by human construction. Three aeolian sand samples, collected from the uppermost (youngest) parts of the fan system in the city area, in places where human intervention has not disturbed the sediment, and constrain the latest dates of fan building. Depositional ages of the Quaternary alluvial fans were measured using Optically Stimulated Luminescence (OSL) on aeolian sands that have inter-fingered with alluvial fan material. These dates are: a) sample P1, 31 ka; b) sample P2, 41 ka; c) sample P3, 74 ka, between Oxygen Isotope Stages (OIS) 3 to 5. They demonstrate that fan development, in the area now occupied by the city, terminated in the Late Pleistocene, immediately after what we interpret to have been an extended period of erosion without further deposition, lasting from the Late Pleistocene to Holocene. The three dates broadly correspond to global glacial periods, implying that the cool, dry periods may reflect periods of aeolian transport in northern Mexico in between phases that were wetter to form the alluvial fans. Alluvial fan margins inter-finger with fluvial terrace sediments derived from the Rio Bravo, indicating an additional component of fan dis by Rio Bravo lateral erosion, presumed to be active during earlier times than our OSL ages, but these are not yet dated. Further dating is required to ascertain the controls on the fan and fluvial system.

This study was undertaken in the south and western regions of the Amazonas Basin to describe the conodont biostratigraphy and paleoecology of Pennsylvanian carbonate rocks of the marine portion of the Tapajos Group comprising the upper Monte Alegre, Itaituba, and lower Nova Olinda formations. The analyzed area includes one outcrop along the Tapajos river (TAP), two carbonate quarries (QI, QII), and 18 wells (dots 1-18). The conodont fauna is dominated by Idiognathoides sinuatus and Neognathodus symmetricus in the Monte Alegre Formation, followed by Idiognathodus incurvus, Diplognathodus coloradoensis and Neognathodus bassleri in the Itaituba and Nova Olinda formations. The conodont association suggests an Early to Middle Pennsylvanian age to the analyzed section. Relative ages attributed to the three lithostratigraphic units using conodonts, palynomorphs, and foraminifers are consistent. Herein are proposed one local taxon-range zone of Idiognathodus incurvus in the Itaituba and lower part of the Nova Olinda Formation and one local taxon-range subzone of Diplognathodus coloradoensis in the Itaituba Formation, suggesting a late Bashkirian - Moscovian (Atokan - early Desmoinesian) age to these strata. The Itaituba Formation marks the establishment of large Pennsylvanian marine conditions in the Amazonas Basin and is composed primarily of marine carbonates of abundant fossil content, tidal flat evaporites and siliciclastic thin intervals. Its lower limit, with the Monte Alegre Formation, is characterized by the predominant occurrence of fluvial-deltaic sandstones superimposed on an extensive sequence of aeolian sandstones, siltstones and shales intercalated with the interdune and lakes. From the upper strata of Itaituba Formation the faunal and lithological characteristics indicate the occurrence of a regressive phase culminating in a restricted environment, arid which indicates the Nova Olinda Formation. This is characterized by the occurrence of evaporites increasingly abundant to the top of carbonates, also shales and siltstones intercalated with the sabkha plain. The carbonate strata have similar marine fossils to those of Itaituba Formation, however, the fauna becomes impoverished in abundance and diversity. The conodont fauna of Early-Middle Pennsylvanian of Amazonas Basin suggests similarities of species with the North American Midcontinent region and the Illinois Basin indicating their probable cosmopolitism; however in a slightly different paleogeographic context, probably due to latitudinal differences, coal deposits are present in North America, whereas widespread evaporitic deposits are registered to the Tapajos Group, Amazonas Basin. (C) 2015 Elsevier Ltd. All rights reserved.

A new borehole in Rozce (SW Mazovian Lowland) drilled in 2012, combined with a wide variety of research methods (palaeomagnetism, palynological analysis, studies of plant macroremains and textural features of deposits) shed new light on the age and stratigraphic position of the Early Pleistocene deposits, formerly assigned as the Lower Pleistocene. The study focuses on the deposits from 50.7-104.0 m depth, between glacial till of the Nidanian Glaciation (ca. 0.9 Ma) and the Poznan Clays (ca. 5.322 Ma). The deposits situated directly underneath the till (50.7-60.2 m) are related to the Nidanian Glaciation and show a reversed polarity and correlate with the end of the Matuyama Epoch. The deposits from 60.2-104.0 m depth were accumulated during the Early Pliocene, i.e. approximately 5.332-4.6 million years ago. They appear to correlate with the middle part of the Gilbert Palaeomagnetic Epoch and thus they are considerably older than previously thought. The cored indicates a stratigraphic gap of about 3.5 Ma from the Lower Pliocene to the first advance of the Scandinavian ice sheets into Poland, which are thought to have occurred in the early Middle Pleistocene. The analysed deposits accumulated under variable climatic conditions showing two periods with significant aridity alternated with two periods of increased humidity. Deposits of the arid periods contain no pollen, but aeolian sand quartz grains are found. During periods of more humid climate the area was covered by various types of mixed forest.

The Saharan regions of Algeria are characterized by a hot and dry climate. The most used cement materials such as the concrete or the mortar blocks have bad thermal characteristic. However, these regions have several local materials: clay, dune sand and some natural fibers, which are formerly proved their thermal efficiency. The price of construction material used therefore depends on the international market constantly destabilized by the economic crisis coupled with the energy crisis in recent times. To produce a framework of life at a lower cost, it is important, therefore, to circumvent the influence of the cost of energy by upgrading the local materials of construction. In order to improve thermal performances in Saharan building materials this study was lanced. The aim of this research isthen to fabricate some bricks using three local materials: namely the clay, sand dune and the fibers of date palm. The percentage of sand and fibers varies from 0% to 40% and 0% to 3% by mass respectively. A sand dune of Ain El Beida of Ouargla of Algeria was used. Clay was extracted from BeldetAmer of TouggourtOuarglaAlgerie. The fibers used in this study were vegetable fibers from date palm of OuarglaAlgeria. The results showed that increasing in the mass fraction of sand and of fiber were beneficial for improving thermal properties. As function of increasing the percentage of sand dune and fibers there were: A decrease in: thermal conductivity, specific heat, heat capacity, thermal effusivity and thermal diffusivity and there were an increase in the thermal resistance.

Despite the large number of studies on biochar and soil properties, few studies have investigated the effects of biochar in contrasting soils. A study was conducted including four rice-husk biochar rates (0%, 0.1%, 0.5% and 1%) to understand the effects on selected soil properties of two Alfisols (sand and sandy loam) in Sri Lanka. Significant changes in soil properties including increases in pH, cation exchange capacity (CEC), organic carbon, water retention at field capacity and saturated hydraulic conductivity, and reduction in bulk density, were observed at higher rates of biochar (0.5% and 1%). Mean-weight-diameter increased only at 1% biochar application rate in sandy soil, whereas it significantly increased across all the rates in sandy loam soil over the control. Electrical conductivity showed no significant increase in either soil, indicating no threat of salinity. Biochar showed a potential for ameliorating acidity, especially in slightly acidic sandy soil. Soil aggregation and water flow improved markedly in sandy loam soil over sandy soil. Further, CEC and water retention of sandy soil had pronounced effects compared with sandy loam soil. Our study highlights the importance of soil type in determining the value of rice-husk biochar as a soil amendment to improve soil aggregation, water retention and flow and CEC.

We conducted a field experiment to determine whether application of biosolids (municipal sewage sludge) to degraded areas of the Brazilian Atlantic rainforest had the potential to contaminate native forest species with trace metals in the sandy soils of the region. Treatments consisted of 0, 2.5, 5, 10, 15, and 20 dry Mg biosolids ha(-1), with nine native pioneer, secondary, and climax tree species assessed for metal uptake: capixingui, aroeira-pimenteria, canafistula, cedro-rosa, mutamba, angico-vermelho, copaiba, jatoba, and jequitiba. Biosolid application did not have a statistically significant effect on metal concentrations in soil, and Cd was the only metal with increased availability. No increased metal uptake was seen in tree foliage sampled at 6 and 12 months after application. Additional longer-term study is recommended; however, the results of this study indicate biosolids could be used in Atlantic rainforest reclamation in degraded sandy soils with little impact on soil accumulation and tree uptake of trace metals.

Increased moisture content leads to increased thermal conductivity and is beneficial for heat exchange of ground-coupled heat exchangers (GCHE). In this study, a horizontal GCHE was combined with a rain garden, characterized by the beneficial supply of rainwater to groundwater, increased soil moisture content and favorable conditions for GCHE. Sandy soil container experiment results showed that water immigration was possible under thermal action of the horizontal GCHE. Compared with little water transfer under the heat evacuation condition, with a relatively small temperature difference between fluid and adjacent soils, heat and water transfer were coupled under the heat rejection condition and a drying region appeared at regions adjacent to the tube wall because of the relatively large temperature difference. Water immigration was more likely to occur when sandy soil had low moisture content, for example 0.1 m(3)/m(3). The coupled heat and water transfer model was necessary for prediction of horizontal GCHE thermal performance. Under high moisture content conditions, the coupled model was dispensable but it was necessary to consider moisture-dependent variation in thermal conductivity. (C) 2015 Elsevier B.V. All rights reserved.

The research was conducted during 2012-2015 in Research - Development Center for Agricultural Plants on Sands Dabuleni, and were aimed the study of 16 cultivars of cowpea in a comparative culture of competition, in order to introduce culture of the most valuable. In sandy soil conditions, the cultivars of cowpea registered a vegetation period in 92-109 days, requiring approximately 1997.2 to 2499.9 degrees C, for maturing. The earliest varieties were: Aura 26, Aura, D4-1, Ofelia, and most late were Jiana, D12 / 2000 cowpea cultivars. The results concerning the productivity elements made from cowpea, indicate values differentiated by cultivar. They were marked by high levels of productivity elements, Aura 26, Ofelia, D2-b / 93, Aura, D2-3a, D3-5 cultivars, which recorded over 11 pods / plant and over 10 grains / pod. Between leaf area index (L.A.I.) and grain yield obtained at cultivars of cowpea, there is a distinct significantly negative correlation. The cultivars of cowpea, which have developed a value of L.A.I. by 5 to 5.4, were recorded the highest grain yields of 2603.7 to 2857 kg/ha (Ofelia, Aura, Aura 26, D2-3a, D3 / 93). Analysis on grain quality by cowpea cultivars, studied in sandy soils conditions, reflects an average protein by 22.4%, with values within limits from 20.5 to 23.8% and fats content with an average of 2.5%, which varied depending on the cultivar, between 1.9 to 2.9%.

The northern region of Piaui state is an important center of irrigated organic fruit farming, wherein sandy soils with low organic matter content are predominant, besides climate with high temperatures, long periods of water deficit and constant wind. Given this situation, it becomes necessary to investigate alternative management options able to meet the challenges of agricultural productivity. In this context, green manuring becomes an important practice, mainly when using fast-growing species and with great potential for biomass production. Thus, a study was carried out at Embrapa Meio-Norte to measure Crotalaria juncea biomass yield after thinning and at various sowing densities. The evaluated parameters were plant height, stem diameter, number of branches per plant, fresh and dry weight of shoots and roots. The results showed that sowing density had no influence on plant height; however, unthinned plants reached greater heights, which might have been due to reduced competition for light. Thinning had no effect on diameters of plant stem base; on the other hand, lower planting densities promoted larger diameters also due to less competition. Likewise, the number of branches per plant was not affected by thinning, being greater at lower planting densities on account of less competition. Thinned plants achieved higher averages of fresh shoot weight. Nevertheless, shoot dry biomass was greater at higher planting densities. Furthermore, both fresh and dry weight of roots were not influenced by any of the adopted treatments.

Climate change is expected to impact the water cycle and severely affect precipitation patterns across central Europe and in other parts of the world, leading to more frequent and severe droughts. Usually when projecting drought impacts on hydrological systems, it is assumed that system properties, like soil properties, remain stable and will not be affected by drought events. To study if this assumption is appropriate, we address the effects of drought on the infiltration behavior of forest soils using dye tracer experiments on six sites in three regions across Germany, which were forced into drought conditions. The sites cover clayey-, loamy- and sandy-textured soils. In each region, we compared a deciduous and a coniferous forest stand to address differences between the main tree species. The results of the dye tracer experiments show clear evidence for changes in infiltration behavior at the sites. The infiltration changed at the clayey plots from regular and homogeneous flow to fast preferential flow. Similar behavior was observed at the loamy plots, where large areas in the upper layers remained dry, displaying signs of strong water repellency. This was confirmed by water drop penetration time (WDPT) tests, which revealed, in all except one plot, moderate to severe water repellency. Water repellency was also accountable for the change of regular infiltration to fingered flow in the sandy soils. The results of this study suggest that the drought history or, more generally, the climatic conditions of a soil in the past are more important than the actual antecedent soil moisture status regarding hydrophobicity and infiltration behavior; furthermore, drought effects on infiltration need to be considered in hydrological models to obtain realistic predictions concerning water quality and quantity in runoff and groundwater recharge.