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The purpose of this research is to determine the sedimentary environment of alluvial terraces south of Khorramabad to Poldokhter using structural elements and limiting surfaces. In line with this goal, 4 sections were identified and studied. The cuttings are located at distances between 60 and 80 kilometers south of Khorram Abad towards Poldokhter. The studies conducted on these sections lead to the identification of 10 rock facies, including 4 gravelly rock facies (Gm, Gms, Gp, Gt), 4 sandy rock facies (Sm, Sp, St, Sh) and 2 rock facies. Flower (Fsm, Fm), 13 structural elements including (GB, HS, C/S, LHF, LCS, CVs, DIs, TCS, OF, CH, SB, SHF, LIS) and 6 limiting levels of rank 1 to 6 became. According to rock faces, limiting surfaces and structural elements under channel environments, channel bars, point bar, wide cuts (crevasse splay), natural embankments (levee).) and flood plain subenvironment were determined for the alluvial terraces south of Khorramabad to Poldokhtar. Structural elements CH, GB, C/S, LHF, SHF were observed in the studied alluvial barracks in abundance, which indicates a river environment with low twist for the studied alluvial terraces, which alternates between at times, it was attacked by strong and destructive floods, and the coexistence of flood channels indicates that they are periodic. [ABSTRACT FROM AUTHOR]

A compliance-based excavation on Parramatta River (western Sydney) found evidence of a brief visitation by Aboriginal people during the terminal Pleistocene (c.14 ka), from which an exotic raw material–medium-grained porphyroblastic andalusite-cordierite hornfels–was recovered. This raw material is rare in the region, only found in the Megalong Valley situated some 75 km west of the site in Parramatta, and separated from the site by the Blue Mountains–a 40 km wide, 1 km high dissected sandstone upland. Historical observations and geological evidence suggest that the Coxs River, which runs through the upland, formed the probable connection between the two locales. The formation of the site at c.14 ka, along with our broader understanding of the region, suggests that the upland was only explored after the Last Glacial Maximum (LGM) and that the Great Dividing Range may have formed a significant barrier to early peopling of Sahul. Further, a delay between the end of the LGM and the exploration of the region implies populations were severely affected by the event and required considerable time to recover. The coincident timing of rapid sea-level rise from Meltwater Phase Pulse 1A and an increased supply of moisture associated with the Antarctic Climate Reversal at the time of many site initiations may have been factors in the upland and south west slopes visitation. Finally, the movement of the unusual hornfels artefact provides a coarse indication of the ranging territory for hunter-gatherers living in a temperate region (c. 8,000 km2) at this time. This is probably a lower estimate but begins to provide a quantitative value with which to begin to ratify the increasing divergence between archaeological and genomic studies in their definitions of mobility, sedentism and regional nomadism. [ABSTRACT FROM AUTHOR]

Copyright of Spal: Revista de Prehistoria y Arqueologia de la Universidad de Sevilla is the property of Spal. Revista de Prehistoria y Arqueologia de la Universidad de Sevilla and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background Biological invasion is one of the main threats to tropical biodiversity and ecosystem functioning. Prosopis juliflora (Sw) DC. (Fabales: Fabaceae: Caesalpinioideae) was introduced in the Caatinga dry forest of Northeast Brazil at early 1940s and successfully spread across the region. As other invasive species, it may benefit from the soils and seed dispersal by livestock. Here we examine how seed dispersal ecology and soil conditions collectively affect seed germination, early seedling performance and consequently the P. juliflora invasive potential. Methods Seed germination, early seedling survival, life expectancy and soil attributes were examined in 10 plots located across three habitats (flooding plain, alluvial terrace and plateau) into a human-modified landscape of the Caatinga dry forest (a total of 12,000 seeds). Seeds were exposed to four seed dispersal methods: deposition on the soil surface, burial in the soil, passed through cattle (Boss taurus) digestive tracts and mixed with cattle manure and passed through mule (Equus africanus asinus × Equus ferus caballus) digestive tracts and mixed with mule manure. Seeds and seedlings were monitored through a year and their performance examined with expectancy tables. Results Soils differed among habitats, particularly its nutrient availability, texture and water with finely-textured and more fertile soils in the flooding plain. Total seed germination was relatively low (14.5%), with the highest score among seeds buried in the flooding plain (47.4 ± 25.3%). Seed dispersal by cattle and mule also positively impacted seed germination. Early seedling survival rate of P. juliflora was dramatically reduced with few seedlings still alive elapsed a year. Survival rate was highest in the first 30 days and declined between 30 and 60 days with stabilization at 70 days after germination in all seed treatments and habitats. However, survival and life expectancy were higher in the flooding plain at 75 days and lower in the plateau. Prosopis juliflora seedling survival and life expectancy were higher in the case seeds were mixed with cattle manure. Synthesis Prosopis juliflora seeds and seedlings are sensitive to water stress and habitat desiccation. Therefore, they benefit from the humid soils often present across human-disturbed flooding plains. This plant also benefits from seed deposition/dispersal by livestock in these landscapes, since cattle manure represents a nutrient-rich and humid substrate for both seeds and seedlings. The quality of the seed dispersal service varies among livestock species, but this key mutualism between exotic species is due to the arillate, hard-coated and palatable seeds. Prosopis juliflora traits allow this species to take multiple benefits from human presence and thus operating as a human commensal.

Background: Biological invasion is one of the main threats to tropical biodiversity and ecosystem functioning. Prosopis juliflora (Sw) DC. (Fabales: Fabaceae: Caesalpinioideae) was introduced in the Caatinga dry forest of Northeast Brazil at early 1940s and successfully spread across the region. As other invasive species, it may benefit from the soils and seed dispersal by livestock. Here we examine how seed dispersal ecology and soil conditions collectively affect seed germination, early seedling performance and consequently the P. juliflora invasive potential. Methods: Seed germination, early seedling survival, life expectancy and soil attributes were examined in 10 plots located across three habitats (flooding plain, alluvial terrace and plateau) into a human-modified landscape of the Caatinga dry forest (a total of 12,000 seeds). Seeds were exposed to four seed dispersal methods: deposition on the soil surface, burial in the soil, passed through cattle (Boss taurus) digestive tracts and mixed with cattle manure and passed through mule (Equus africanus asinus × Equus ferus caballus) digestive tracts and mixed with mule manure. Seeds and seedlings were monitored through a year and their performance examined with expectancy tables. Results: Soils differed among habitats, particularly its nutrient availability, texture and water with finely-textured and more fertile soils in the flooding plain. Total seed germination was relatively low (14.5%), with the highest score among seeds buried in the flooding plain (47.4 ± 25.3%). Seed dispersal by cattle and mule also positively impacted seed germination. Early seedling survival rate of P. juliflora was dramatically reduced with few seedlings still alive elapsed a year. Survival rate was highest in the first 30 days and declined between 30 and 60 days with stabilization at 70 days after germination in all seed treatments and habitats. However, survival and life expectancy were higher in the flooding plain at 75 days and lower in the plateau. Prosopis juliflora seedling survival and life expectancy were higher in the case seeds were mixed with cattle manure. Synthesis: Prosopis juliflora seeds and seedlings are sensitive to water stress and habitat desiccation. Therefore, they benefit from the humid soils often present across human-disturbed flooding plains. This plant also benefits from seed deposition/dispersal by livestock in these landscapes, since cattle manure represents a nutrient-rich and humid substrate for both seeds and seedlings. The quality of the seed dispersal service varies among livestock species, but this key mutualism between exotic species is due to the arillate, hard-coated and palatable seeds. Prosopis juliflora traits allow this species to take multiple benefits from human presence and thus operating as a human commensal. [ABSTRACT FROM AUTHOR]

Copyright of Acta Zoologica Lilloana is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We document the temporal evolution of deformation in the northern Tianshan piedmont where the deformation is partitioned across several thrusts and folds. We focus on the Dushanzi anticline, where abandoned terraces and growth strata allow us to constrain the history of folding since the Miocene. Based on subsurface seismic imaging, structural measurements and morphological analysis, we show that this anticline is associated with two decollement levels. We use kink band migration in growth strata dated by paleomagnetism to constrain the shortening from the Mio-Pliocene to the Holocene. Our results show that the Dushanzi anticline has been active since at least 8 Ma and that the fold grew at a steady shortening rate of 0.6 ± 0.1 mm/yr from 8 to ~1.5 Ma with possible variations from 2.5 to 1.5 Ma. Then it accelerated rapidly to a rate of 4.3 ± 1.0 mm/yr over at least the last 100 ka. These results, together with similar temporal shortening evolutions across other structures, suggest that the deformation rate across the eastern Tianshan piedmont increased relatively recently. This may reflect either a redistribution of the deformation from the internal structures toward the borders or a general acceleration of the deformation across the entire range. [ABSTRACT FROM AUTHOR]

Two stages are distinguished in the study of Quaternary deposits in Crimea. At the first stage (from the late 19th century to the 1960s), the stratigraphic description of Quaternary strata was based on the allocation of terraced complexes (marine terraces in the coastal part and synchronous alluvial terraces in the continental part of the Crimean Peninsula). At the second stage, the description of Quaternary deposits was based on their climatostratigraphic classification, with the leading role of the loess-soil formation. The structure of the paleo-Dnieper and paleo-Dniester valleys was used as the basis for the stratigraphic subdivision of Quaternary deposits in Crimea. It is shown that the nonlinear reversible changes of the Black Sea level that took place in the Quaternary can break the rule that the lower the hypsometric level of a terrace is, the younger the terrace is. [ABSTRACT FROM AUTHOR]

High temperatures and rainfall prevail in the Brazilian Amazon, but some areas have soils with high clay mineral contents of 2:1, and there is limited information concerning their properties. Therefore, it is important to study the soil formation and understand the environmental conditions in which they were formed. This study aimed to investigate the physical, chemical and mineralogical properties of the soil in relation to the environmental factors acting on a chronosequence in the Late Pleistocene sediments of the Middle Madeira River. Soil profiles were selected on three alluvial terraces. Morphological, physical, chemical, mineralogical, X-ray fluorescence, TEM and SEM characterizations were performed. The soils that exhibited a clayey texture, acidic reaction, low values of exchangeable bases and high values of aluminum had profiles containing a considerable presence of 2:1 clay minerals, especially illite, vermiculite, mica-vermiculite, hydroxyl-interlayered vermiculite and pyrophyllite. Soil mineralogy indicated that these soils were recently weathered, where the low values of sum of bases correspond to the low presence of these cations in the parent material. Meanwhile, high values of exchangeable aluminum were derived from the pyrophyllite alteration, different parent material and 2:1 clay minerals recent alteration. Therefore, the parent material, presence of amorphous silica, different climate conditions in the past and current drainage restriction contribute to the slow alteration rate of 2:1 clay minerals of the soils of the humid tropical Amazon environment. [ABSTRACT FROM AUTHOR]

doi: http://dx.doi.org/10.15447/sfews.2015v13iss3art2

Sequences of alluvial fill-terraces record the long-term variation of fluvial transport regimes in response to Quaternary climatic changes. Through a production of increasingly precise chronologies, the broadening range of sediment dating methods in recent years has improved our understanding of correlations between alluvial dynamics and external forcing mechanisms. However, results in this field have mostly focused on periglacial and other mid-latitude settings. These may not readily apply to glaciofluvial environments, where alluvial regimes are narrowly dependent on the behavior of the adjacent ice-field. Here we constrain the ages of three glaciofluvial fill terraces based on five vertical 10 Be age profiles in the Ariège River catchment, and produce a chronofunction of related contrasts in terrace tread topsoil characteristics. Each profile consists of 9 to 11 gravel samples collected over depths of 4.6 to 15 m. Terrace T1 (+ 15 m above the current riverbed) was sampled at ~ 4, 22 and 53 km downstream from the Last Glacial Maximum terminal moraine system of the Ariège outlet glacier. The profiles of T2 (+ 30 m) and T3 (+ 50 m) complete the data set. Beryllium-10 age profiles date the age of terrace tread abandonment as a result of fluvial incision. Results show that the incision of T1 occurred over a protracted period during the Last Termination, beginning ca. 17.5 – 3.5 + 2.0 ka. Prior to this, aggradation occurred from MIS 4 to the global Last Glacial Maximum (LGM), i.e.,under maximum ice extent conditions, and lasted a few thousand years thereafter. The protracted influx of debris after the LGM was sustained by paraglacial storage release in the catchment and promoted by strong coupling between slope and channel processes. Fluvial incision of T1 occurred during the post-LGMcold-to-warm transition after a time (supported by paleobotanical evidence) when the vegetation cover was capable of ensuring catchment-wide slope stability. The wave of incision propagated downstream between 17.5 – 3.5 + 2.0 ka (proximal profile) and 13.0 – 0.5 + 3.5 ka (distal profiles). The exposure-age confidence intervals for T2 and T3 are much larger than for T1 (60–145 ka and 204–226 ka, respectively) but the data nonetheless allow the aggradation of T2 and T3 to be attributed to MIS 6 and MIS 8, respectively. The soil chronosequence permitted by the fill-terrace age sequence indicates that the Luvic Cambisols capping T1 formed after ~ 13–16 ka, i.e.,during the Holocene; (ii) the Haplic Luvisols capping T2 required at least ~ 130 ka, i.e.,two interglacials; and (iii) the deeply rubified, highly eluviated Luvisols capping T3 required at least ~ 250 ka, i.e.,at least three interglacials. [ABSTRACT FROM AUTHOR]

Abstract: Although dominated by erosion over long term, the tectonically active mountains of Taiwan commonly contain thick landslide and debris-flow gravels capping hillslopes or forming alluvial terraces. These deposits and their associated landforms serve to study ancient mass-wasting histories and their controls on fluvial processes. This study focuses on the Pa-chang River draining the <2000m high Ali-shan area in southwestern Taiwan (current tectonic uplift: 5–8mmyr−1). Although small (catchment area: 83km2), the Pa-chang exhibits one of the largest alluvial terraces in Taiwan, which stretches from the outlet of the catchment for 9km along the river and comprises fluvial and debris-flow gravels up to 150m thick. Totally 55 radiocarbon dates have been obtained, tracing the mass-wasting records back to 14.8ka. The largest events, which created the studied major terraces, occurred in 10.0−11.3 and 8.7−9.4ka. These events are synchronous with the formation of some regionally largest alluvial terraces in Taiwan, and may have been triggered by the frequent heavy rains associated with the early Holocene East Asian summer-monsoon maximum. More mass-wasting events have been dated at ~5.4, ~1.9, 1.2−1.7, 0.7−0.9, ~0.6, and <0.3ka. The vast supply of sediment from the recorded mass-wasting events not only caused river aggradation but also regulated the subsequent incision by forming boulder armors. As a result, the bedrock incision in the upper part of the catchment has been negligible since the early Holocene debris-flow deposition. The incision rates increase to the downstream direction as the size and concentration of boulders reduce. Still, the 14.8ka-averaged bedrock incision rate (<4.5mmyr−1) at the catchment outlet is lower than the current uplift rate (6mmyr−1). At the same site, however, the bedrock incision rate is 23mmyr−1 averaged over the past 0.6ka. Even higher rates of incision (>50mmyr−1) are detected further downstream after the recent gravel mining. The fact that the obtained bedrock incision rates and patterns are decoupled with the tectonic uplift advises caution in using short-term erosion data to interpret the tectonics of the Taiwan's mountains. [Copyright &y& Elsevier]

The aim of this study was to investigate the influence of mining on the geochemical composition of the alluvial sediments of the Gualaxo do Norte River Basin, located in the eastern-southeastern portion of the Quadrilátero Ferrífero (Minas Gerais State, Brazil). The analysis of the sedimentological succession was carried out using 16 stratigraphic sections (cutbanks and alluvial terraces) and analysis of 111 sediment samples for major- and trace-elements by ICP-OES. The stratigraphic analysis revealed the deposition history of the collected sediments. Anomalous concentrations of certain elements such as As and Pb were found, which are associated with stratigraphic facies with evidences of gold artisanal mining, and Fe anomalies associated with iron ore mining. The classification of the sections was possible by means of principal component analysis. From the sediment characteristics, three groups were identified: (1) those influenced by iron ore mining and gold artisanal mining; (2) those influenced by iron ore mining and (3) those with no influence of human activities. [ABSTRACT FROM AUTHOR]

Abstract: The influence of salmon-derived nutrients (SDN) is widely accepted as a potential factor in the maintenance of aquatic and terrestrial productivity in North American Coastal rainforests. Holocene alluvial landforms are intimately connected with the return of anadromous salmon, but the influence of the soils that occupy these landforms and support this important terrestrial–aquatic ecological coupling have not been examined in SDN studies. We used paleo-ecologic information, soil resource inventories and measurements of soil morphology to construct a soil-geomorphic model for alluvial landforms along salmon spawning channels on Prince of Wales Island, Southeast Alaska, USA. Post-glacial sea-level rise, crustal uplift and subsidence combined with Holocene sediment deposition have formed alluvial terraces and floodplains along rivers on Prince of Wales Island. These alluvial landforms have soils that are mapped as Entisols (Tonowek soil series) and Spodosols (Tuxekan soil series). We propose a soil-geomorphic model where the Spodosols located on terraces are estimated to derive from sediments deposited after the stabilization of landscape approximately 8kybp to 6kybp. The stability of these soils is reflected through mature soil development with organic matter accumulation and podzolization. Our model identifies Entisols on floodplains developed from alluvial deposition in the latter Holocene that have soil morphologic features consistent with recent deposition and limited soil development. We used this soil-geomorphic model to test the hypothesis that the terrestrial end-member value commonly used to quantify nitrogen (N) loading on soils through stable isotope analysis differs by soil type and found that the two soil types had significantly different N isotopic (δ 15N) values more consistent with soil development than SDN loading. The use of a soil-geomorphic model provides a means to stratify alluvial landforms and constrain the natural variability encountered in studies of riparian nutrient cycles associated with the feedbacks between SDN and terrestrial ecosystems to improve estimates of the fate of SDN in soils and vegetation. [Copyright &y& Elsevier]

Background: Biological invasion is one of the main threats to tropical biodiversity and ecosystem functioning. Prosopis juliflora (Sw) DC. (Fabales: Fabaceae: Caesalpinioideae) was introduced in the Caatinga dry forest of Northeast Brazil at early 1940s and successfully spread across the region. As other invasive species, it may benefit from the soils and seed dispersal by livestock. Here we examine how seed dispersal ecology and soil conditions collectively affect seed germination, early seedling performance and consequently the P. juliflora invasive potential., Methods: Seed germination, early seedling survival, life expectancy and soil attributes were examined in 10 plots located across three habitats (flooding plain, alluvial terrace and plateau) into a human-modified landscape of the Caatinga dry forest (a total of 12,000 seeds). Seeds were exposed to four seed dispersal methods: deposition on the soil surface, burial in the soil, passed through cattle ( Boss taurus ) digestive tracts and mixed with cattle manure and passed through mule ( Equus africanus asinus × Equus ferus caballus ) digestive tracts and mixed with mule manure. Seeds and seedlings were monitored through a year and their performance examined with expectancy tables., Results: Soils differed among habitats, particularly its nutrient availability, texture and water with finely-textured and more fertile soils in the flooding plain. Total seed germination was relatively low (14.5%), with the highest score among seeds buried in the flooding plain (47.4 ± 25.3%). Seed dispersal by cattle and mule also positively impacted seed germination. Early seedling survival rate of P. juliflora was dramatically reduced with few seedlings still alive elapsed a year. Survival rate was highest in the first 30 days and declined between 30 and 60 days with stabilization at 70 days after germination in all seed treatments and habitats. However, survival and life expectancy were higher in the flooding plain at 75 days and lower in the plateau. Prosopis juliflora seedling survival and life expectancy were higher in the case seeds were mixed with cattle manure., Synthesis: Prosopis juliflora seeds and seedlings are sensitive to water stress and habitat desiccation. Therefore, they benefit from the humid soils often present across human-disturbed flooding plains. This plant also benefits from seed deposition/dispersal by livestock in these landscapes, since cattle manure represents a nutrient-rich and humid substrate for both seeds and seedlings. The quality of the seed dispersal service varies among livestock species, but this key mutualism between exotic species is due to the arillate, hard-coated and palatable seeds. Prosopis juliflora traits allow this species to take multiple benefits from human presence and thus operating as a human commensal., Competing Interests: Wagner de Souza Tavares is employed by Asia Pacific Resources International Holdings Ltd. (APRIL), PT. Riau Andalan Pulp and Paper (RAPP)., (© 2020 Nascimento et al.)