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[Objective] In order to clarify the law of sediment yield and sediment loss of different land use types under different rainfall types, and to evaluate the benefit of sediment reduction of different land use types under different rainfall types. [Methods] Based on the monitoring data of runoff and soil loss under natural rainfall conditions over 2015—2016 in 31 runoff plots located in the Loess Plateau of China the characteristics of sediment yield and loss in different land use types, including farmlands, abandoned lands, artificial grasslands, natural grasslands, shrublands and artificial forest lands were discussed. The efficiency of runoff and sediment reduction for each land use type under different rainfall types was determined. [Results] The runoff and soil loss of abandoned lands were the largest (30 mm, 86 t/hm2) and artificial forest lands were the smallest (8 mm, 24 t/hm2) under the annual rainfall scale, and there was no significant difference between other land use types. Through the application of duster analysis a total of 120 rainfall events were categorized into three distinct rainfall types based on criteria that included amount, duration, and maximum intensity of rainfall in a 30-minute period. That is, Rainfall Type I: characterised by moderate rainfall duration (749 min), moderate rainfall volume (35.4 mm), and moderate rainfall intensity (16.9 mm/h); Rainfall Type II: comprising short-duration rainfall (222 min), moderate rainfall volume (25.2 mm), and intense rainfall intensity (23.8 mm/h); Rainfall Type III: involving a long duration of rainfall (1 451 min), substantial rainfall volume (40.6 mm), but low intensity of rainfall (11.5 mm/h). When considering the impact of these types of rainfall within the given scale, the study observed the following trends, for the runoff coefficient, exhibiting Rainfall Type II > Rainfall Type III > Rainfall Type I, while for soil loss, exhibiting Rainfall Type II > Rainfall Type I > Rainfall Type III. The runoff coefficient of Rainfall Type I was significantly higher than that of other land use types, reaching 17.7%, which was 2.36 times that of artificial forest land. There were no significant difference in runoff coefficient under Rainfall Type II, and the average runoff coefficient was 19.9%. The runoff coefficient of abandoned lands, artificial grasslands, natural grasslands, and farmlands (average of 14.3%) was significantly higher than that of shrublands and artificial forest lands (averaging at 9.0%). The soil loss of famlands, artificial grasslands, shmblands and artificial forest lands under Rainfall Type II (3.94, 0.87, 1.06, 1.08 t/hm2) > Rainfall Type I (1.60, 0.60, 0.59, 0.63 t/hm2) > Rainfall Type III (0.09, 0.20, 0.06, 0.04 t/hm2). [Conclusion] In the Loess Plateau, the artificial forest land was the first choice to control soil and water loss effectively under the condition of medium-low rainfall intensity and medium-long duration rainfall, and the soil and water conservation effect of shrubland and grassland was better under short-duration heavy rainfall.

Copyright of Journal of Soil & Water Conservation (1009-2242) is the property of Institute of Soil & Water Conservation 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.)

Many empirical relationships have been proposed to relate the sediment volume to various influencing factors. However, the accuracy of such empirical relationships generally requires a large number of observation data, which is difficult to guarantee at a specific site. Moreover, based on the limited investigation data, a complicated empirical model with more input factors may be an overfitted equation. Therefore, how to develop a reliable prediction model of debris-flow sediment volume still remains a great challenge. This paper develops a probabilistic method to establish the most appropriate empirical model for predicting the debris-flow volume based on Bayesian inference. First, the limited site investigation data are preprocessed by a series of multicollinearity analysis to select the candidate input variables. Then, a Bayesian framework is developed to select the most appropriate model among alternatives and identify its corresponding model parameters based on the site investigation data and prior knowledge. To address the multidimensional issues in Bayesian inference, a multichain method, specifically the DREAM(ZS) algorithm, is used to obtain the posterior distribution of model parameters of a candidate model to overcome the inefficient sampling problems of single-chain Markov chain Monte Carlo methods (e.g., Metropolis–Hastings algorithm). The DREAM(ZS) algorithm is subsequently integrated with Gaussian copula to calculate the evidence of a candidate model, making it feasible in the model selection problem. Results show that compared with the preexisting empirical relationship, the proposed approaches can provide a more accurate and simpler empirical model by reasonably considering the balance between data fitting and model uncertainty. [ABSTRACT FROM AUTHOR]

Port is one of the transportation networks that connect sea and land transportation. Thus, it can be ensured that there are many activities closely related to port such as planning, implementation, and maintenance. One of the port maintenance activities is dredging. The sea current that is always moving carries sediment towards the port causing sedimentation in the port pool area and preventing the ship from grounding. Maintenance dredging is required to remove sediment deposits in the pool port to maintain the safety depth. Before dredging, the parameter that has to be considered is the sediment type and its thickness in the area of interest. The study utilized underwater acoustic remote sensing instruments such as Sub Bottom Profiler, Side Scan Sonar, and Multibeam Echosounder to determine the type and thickness of sediments in the port pool. The validation process for the sediment types and the Standard Penetration Test value are derived from the soil investigation data. There are six borehole points at the research location which have a Standard Penetration Test value. The research location is in a shallow water area with depth values ranging from 0.5 m to 7.0 m with respect to Low Water Spring. Based on the SSS image interpretation, the research location is dominated by sediment type of clay. The area of interest is 30541.29 m² and the total volume of the sediment thickness is 82326.7 m³ with respect to the depth design. This sediment volume is dominated by the soft sediment with the volume of 79614.8 m³. The couple of underwater acoustic remote sensing and soil investigation can provide a continuous representation of the sediment thickness and an essential reference for future research on the estimation of sediment volume in the port pool. [ABSTRACT FROM AUTHOR]

The Noahic Flood deposited and emplaced a significant amount of sedimentary and volcanic rock on the continents. Much of it remains despite appreciable Recessional Stage erosion. How much? We answer using a method in Colorado as a pilot for many other locations. The principle is simple: creating grids of the basal and upper diluvial boundaries, then subtracting the lower from the upper. In Colorado, we chose the top of the Precambrian crystalline surface as our basal boundary and digitized a Colorado Geological Survey map into a Geographic Information System (GIS). NOAA's ETOPO1 Digital Elevation Model (DEM) of surface topography was selected as the upper boundary. Small volumes of Precambrian sedimentary and metasedimentary rocks and most of the San Juan and Thirty-Nine Mile volcanic fields were not included in the final calculation, and minor postdiluvial sediments were ignored. The total Flood rock record in Colorado totals more than one-half million cubic kilometers, predominantly in six sedimentary basins. Our method allows recalculation for revised or alternate boundaries. [ABSTRACT FROM AUTHOR]

The Port of Klaipėda, located at the Klaipėda strait, divides the Lithuanian coast into two different geomorphological parts: southern—the coast of the Curonian Spit, and northern—the mainland coast. Port jetties interrupt the main sediment transport path along the South-Eastern Baltic Sea's coast. Port of Klaipėda reconstruction in 2002 and the beach nourishment project which started in 2014 significantly influenced the northern part of the coast, which led to changes in the coastal zone evolution. The measurements in various periods are essential for cross-shore profile elevation to analyze seabed morphology and sedimentation patterns. These data highlight our understanding of the scale and timing of seabed erosion or sedimentation processes scale and timing. This study evaluates the impact of anthropogenic pressure and natural factors on coastal geomorphology and dynamics. In order to assess the latter changes, the cross-shore profile evolution and sediment budget were analyzed as well as nearshore bathymetry changes. The data illustrated a changing picture of the entire shore profile—on land and underwater. [ABSTRACT FROM AUTHOR]

The Ganga River is one of the largest river systems in the world that has built extensive alluvial plains in northern India. The stretch of the Lower Ganga River is vulnerable to siltation because of: (a) the naturally low slope in the alluvial stretch; (b) the confluence of several highly sediment‐charged rivers such as the Ghaghra, Gandak, and Kosi; and (c) the reduction in non‐monsoon flows because of upstream abstractions of both surface and groundwater. Additionally, the Farakka barrage has impacted the morphology of the Ganga River significantly, both upstream and downstream of the barrage. Large‐scale siltation in several reaches has reduced the channel capacity, leading to catastrophic floods in this region even at low discharges. This work has utilized historical remote sensing data and UAV surveys to reconstruct channel morphodynamics and compute sediment volumes accumulated in the channel belt along the Lower Ganga River between Buxar and Farakka. The work was carried out by dividing the total length of the river into four continuous stretches: (a) Buxar–Gandhighat (GW1, 160 km); (b) Gandhighat–Hathidah (GW2, 106 km); (c) Hathidah–Azmabad (GW3, 182 km); and (d) Azmabad–Farakka (GW4, 132 km). We document that major 'hotspots' of siltation have developed in several reaches of the Lower Ganga during the last four to five decades. Sediment budgeting using planform maps provides estimates of 'extractable' volumes of sediment in GW1, GW2, GW3, and GW4 as 656 ± 48, 706 ± 52, 876 ± 71, and 200 ± 85 Mm3, respectively. These estimates are considerably lower than those computed from the hydrological approach using observed suspended sediment load data, which assumes uniform sedimentation between two stations. Further, our approach provides reach‐scale hotspots of aggradation and estimates of extractable sediment volumes, and this can be very useful for river managers to develop a strategic sediment management plan for the given stretch of the Ganga River. [ABSTRACT FROM AUTHOR]

Sequence stratigraphic concepts have a variety of applications well beyond hydrocarbon exploration. Through coastal plain-to-shelf stratigraphic correlation of Last Glacial Maximum deposits from the Central Adriatic area, we tested a source-to-sink approach for exploring offshore groundwater reserves stored within the lowstand systems tract. Above an erosional unconformity (sequence boundary) formed at the Marine Isotope Stage 3–2 transition in response to sea-level fall, lowstand fluvial gravel-sand bodies, up to 20 m thick, can be tracked continuously downstream, from the coastal-plain paleovalleys to the shelf, 30 km away from the modern shoreline. The LST is overlain by a mud-dominated wedge (TST + HST) made up of alluvial, estuarine and delta plain deposits in lateral transition to thick shallow-marine and prodelta clay successions. Using three catchment-to-shelf transects, 35–70 km long, we document the separation between potential reservoir/aquifer units (LST), primarily made of coarse-grained (porous) deposits, and the overlying, laterally continuous seal (TST + HST), which mainly includes fine-grained (low permeability) estuarine to marine sediments. Thickness maps of reservoir/aquifer and seal units provide a three-dimensional view of the stratigraphic architecture and of accumulation patterns at the systems tract scale. Lowstand fluvial deposits spread across a 5600 km2 wide area of the western Central Adriatic shelf, with average thickness of about 10 m. North of the Meso-Adriatic Deep (MAD), two major depocenters, up to 60 m thick, reflect the local highest fluvial sediment load that correlates, further offshore, to the lowstand Po Delta. West of the MAD, LST deposits, up to 25 m thick, were nourished by Apennine rivers. In the southern area, lowstand deposits are <10 m thick. The LST is overlain across the entire western Central Adriatic shelf by an up to 80 m-thick succession of TST + HST fine-grained deposits. A first assessment of sediment volumes provides a value of 130 km3 for TST + HST and 57.2 km3 for LST. Sediment provenance analysis delineates the contribution to the shelf of individual detrital sources (Apennine rivers from the west, Po River from the north), offering a powerful tool in quantifying sediment fluxes (about 52 km3 from the Apennines catchments and 5 km3 from the lowstand Po system). As a whole, the application of sequence stratigraphic concepts led, for the first time, to the identification of a potential groundwater reservoir stored beneath the western Central Adriatic shelf. This LST aquifer possibly contains about 13.85 km3 of groundwater (the salinity of which is unknown), and is vertically confined by a thick, low-permeability unit (i.e., TST + HST) that might have prevented salt-water intrusion into the underlying aquifer. The documented stratigraphic continuity likely makes this offshore aquifer an actively recharging system, with important implications for possible future sustainable exploitation. • We tested a systems-tract scale methodology for offshore groundwater exploration. • High-resolution stratigraphic correlation extends from alluvial plain to shelf environments. • We mapped extensive LST fluvial deposits across the western Central Adriatic shelf. • Sediment volumes were assessed through 3D stratigraphic reconstructions. • About 13.85 km3 of groundwater are stored in the LST confined aquifer. [ABSTRACT FROM AUTHOR]

This laboratory study examines the potential use of an anionic polyacrylamide (PAM)-based material as an environmentally sustainable additive for the stabilization of an expansive soil from South Australia. The experimental program consisted of consistency limits, sediment volume, compaction and oedometer cyclic swell–shrink tests, performed using distilled water and four different PAM-to-water solutions of PD = 0.1 g/L, 0.2 g/L, 0.4 g/L and 0.6 g/L as the mixing liquids. Overall, the relative swelling and shrinkage strains were found to decrease with increasing number of applied swell–shrink cycles, with an ‘elastic equilibrium’ condition achieved on the conclusion of four cycles. The propensity for swelling/shrinkage potential reduction (for any given cycle) was found to be in favor of increasing the PAM dosage up to PD = 0.2 g/L, beyond which the excess PAM molecules self-associate as aggregates, thereby functioning as a lubricant instead of a flocculant; this critical dosage was termed ‘maximum flocculation dosage’ (MFD). The MFD assertion was discussed and validated using the consistency limits and sediment volume properties, both exhibiting only marginal variations beyond the identified MFD of PD = 0.2 g/L. The accumulated axial strain progressively transitioned from ‘expansive’ for the unamended soil to an ideal ‘neutral’ state at the MFD, while higher dosages demonstrated undesirable ‘contractive’ states.

The Port of Klaipėda, located at the Klaipėda strait, divides the Lithuanian coast into two different geomorphological parts: southern—the coast of the Curonian Spit, and northern—the mainland coast. Port jetties interrupt the main sediment transport path along the South-Eastern Baltic Sea’s coast. Port of Klaipėda reconstruction in 2002 and the beach nourishment project which started in 2014 significantly influenced the northern part of the coast, which led to changes in the coastal zone evolution. The measurements in various periods are essential for cross-shore profile elevation to analyze seabed morphology and sedimentation patterns. These data highlight our understanding of the scale and timing of seabed erosion or sedimentation processes scale and timing. This study evaluates the impact of anthropogenic pressure and natural factors on coastal geomorphology and dynamics. In order to assess the latter changes, the cross-shore profile evolution and sediment budget were analyzed as well as nearshore bathymetry changes. The data illustrated a changing picture of the entire shore profile—on land and underwater.

In assessing the removal of dams, it is important to consider the degree to which these efforts could affect channel evolution. A number of previous studies have analyzed the problem of channel evolution using frameworks based on the diffusion equation. In this study, we adopted a similar analytical framework to examine one‐dimensional channel evolution within an infinite channel following dam removal. The Fourier transform is used to obtain an analytical solution which is further used to determine the volume of sediment and position of knickpoints. Analytical results obtained using the proposed models were compared with experiment results reported by Cantelli et al. (2004), https://doi.org/10.1029/2003wr002940 and in‐situ data related to the Balin dam break in Taiwan. We determined that the rate of sediment volume change is proportional to t−1/2 in the early period and t−3/2 in the intermediate period, before eventually decreasing to nearly zero. The proposed solution also makes it possible to derive qualitative and quantitative predictions pertaining to bed elevation, sediment volume, and knickpoint positions. Key Points: Developing an analytical model of channel evolution following dam removal based on a diffusion frameworkDeriving the rate of change in sediment volumes and knickpoint migration with the asymptotic approachThe proposed model deals with diffusivity in a time‐dependent manner [ABSTRACT FROM AUTHOR]

Sediments retained in hydrological correction check dams are a useful source of information to understand soil erosion rates and sediment fluxes. Two hundred sixty nine check dams distributed in an area of 239 ha in SW Spain accumulated sediments over a period of 11 to 23 years. The aim of this work is to estimate the volume of sediments deposited in those check dams and to study the spatial variability of the accumulated sediments and its relationships with different environmental variables. The methodology included five steps: 1) flying the study area with a fixed-wing Unmanned Aerial Vehicle to capture high-resolution aerial photographs, 2) Structure-from-Motion photogrammetry, 3) processing the obtained point clouds and Digital Elevation Models (DEMs) to create the current topography and model the past soil surface, 4) estimating the volume of sediments behind each check dam using a topographic technique and 5) exploring the relationship between sediments and different environmental variables. A total of 269 check dams were identified, from which 160 were suitable to quantify the deposited sediment volume. The volume of sediments trapped by individual check-dams ranged from 0 to 108.35 m3, with an average deposition rate of 0.141 m3 ha−1 y−1. The 77% of the check dams retained <1 m3 of sediment. The topographic position and the size of the dam wall played a fundamental role in explaining the differences of total sediment accumulation as well as the deposition rates. Deposition rate was negatively correlated with drainage area, connectivity index, stream power index, topographic wetness index, upstream channel length and the number of upstream check dams. Conversely, deposition rate was positively correlated with the slope of the channel. Those dams located in valley bottoms with longer walls retained more sediment, while those of hillslopes with shorter check dam walls were ineffective. Unlabelled Image • Depth of sediment deposit was accurately estimated using the proposed workflow. • The proposed methodology overcomes limitations to traditional topographic methods. • Some check dams efficiently retained sediment, particularly in valley bottoms. • Deposition rate was negatively correlated with drainage area and connectivity. • The mapped CI proved to be a valuable resource to guide suitable check dam locations. [ABSTRACT FROM AUTHOR]

Caudle, T.L.; Paine, J.G.; Andrews, J.R., and Saylam, K., 2019. Beach, dune, and nearshore analysis of southern Texas Gulf Coast using Chiroptera LIDAR and imaging system. Journal of Coastal Research, 35(2), 251–268. Coconut Creek (Florida), ISSN 0749-0208. LIDAR data and color infrared aerial imagery were acquired for southern Padre Island and Brazos Island, Texas, in 2013 to calculate rates of shoreline change; analyze beach-dune system volume; and test bathymetric LIDAR capabilities along the Texas Gulf of Mexico shoreline. Data were acquired using a Chiroptera airborne system, which simultaneously collects topographic and bathymetric LIDAR and high-resolution imagery. Shoreline position was extracted from LIDAR digital elevation models (DEMs) to compare with historical shoreline positions for shoreline change analyses. Long-term rates (1937–2013) of gulf shoreline change for southern Padre Island and Brazos Island averaged 2.2 m/y of retreat, with 86% of sites retreating. Retreat rates decreased over the last decade (2000–13) to 1.1 m/y (76% of sites retreating). The trend changed between 2010 and 2013: 64% of monitoring sites advanced at an average distance of 4.9 m. Beach and dune volumes above threshold elevations (1 to 6 m above mean sea level) were extracted from DEMs to assess geographic and temporal patterns of sand storage. The undeveloped area of southern Padre Island had 2 to 4 times the volume of sand at lower threshold elevations and 7 times the volume at higher elevation thresholds than did the heavily developed southernmost section of the island. A constant trend across the study area is that volume reduced by approximately half with each 1 m increase in threshold elevation. Beach and dune system volume in the study area increased steadily since 2000, mirroring the decreased retreat rates observed in the shoreline movement analysis. Possible causes of the decreased shoreline retreat rates and increased subaerial sand storage are a lack of tropical cyclone impacts to the study area during the most recent periods, as well as sediment contribution from beach nourishment activities. Bathymetric LIDAR detected the seafloor in low-turbidity areas less than 4 m deep. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department 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.)

In this study, the influence of different coastal processes, including ocean-atmospheric processes of regional scale, on the spatiotemporal variability of the morphodynamic from the emerged zone of a beach in the Colombian eastern tropical Pacific, specifically in the macrotidal regime's Playa La Bocana, was analyzed during 2014–2019. The linear dependence of the sediment volume on the tide, rainfall, and winds was quantified using Pearson correlations and with large-scale oceanic and climatic relationships, that could be related to sediment volume anomalies. The highest correlation sediment volume monthly mean values are presented with the tide on an intra-annual scale. On an inter-annual scale, the sea surface temperature and sea level pressure composites were consistent with the El Niño-Southern Oscillation patterns. Thus, a cooling (warming) of the tropical Pacific is associated with a higher (lower) sediment volume onshore at Playa La Bocana. Furthermore, it was found that increase (decrease) on Swell (Mean Wave Period and Significant Wave Height) decreased (increased) the volume of sediments. These results show that the tide is the main modulator of beach sediment volume changes under the macrotidal regime, on the intra-annual scale, and that on the inter-annual scale, sediment volume responds to the combined effect of the tide and changes in swell intensity modulated by ENSO conditions. • The method used in our study becomes a complementary alternative to identify the dominant processes in the morphodynamics of the beach, based on reanalysis data. • Intra-annual sediment volume averages identified the tide as the engine of change. • Sediment volume responds to the combined effect of the tide and changes in swell intensity modulated by ENSO conditions at the inter-annual scale. • The analysis of the annual series of sediment volume anomalies and the ONI index showed negative anomalies of sediment volume in Playa La Bocana from 2014 to 2015, confirming the relationship between El Niño periods erosive processes. [ABSTRACT FROM AUTHOR]

Gully erosion is widespread in Nigeria and has been reported in all the states of the Federation: This study was carried out to examine the relationships between gully length (L) and average gully depth (D) on two geological sediments of varying vulnerability to erosion. The dimensions of thirty-seven and five random gully samples formed respectively on the Ajalli Sandstones (AS) and the Upper Coal Measures’ (UCM) geological sediments underlying the Idah-Ankpa Plateau of North Central Nigeria were measured: The L and D variables were subjected to correlation analysis and the sample bivariate regression to examine their relationships and the predictability of D using L as a prediction tool on the two formations. Results show that on the highly erodible AS, L has no correlation with D (R=0.004, R2 =0.00). On the more resistant UCM, L is strongly, significantly, but negatively correlated with D (R=–0.899, R2 =0.808, P<0.05). The regression analyses indicate that L is not a predictive tool for D on the erodible AS (D1 = 6.469 + 0.00L1), whereas on the more resistant UCM, L is a useful parameter for the prediction of D (D2=13.929 – 0.022L2), which appears in the form of bed aggradation. The study suggests that the correlation of gully length with average depth transmutes to a stronger, negative, and significant value with increasing resistance to erosion of the geological formation housing the gully. It also suggests that the reliability of the gully average depth estimation using the length as a prediction tool improves with increasing resistance to erosion of the geological sediments. However, the relationship of gully length with the average depth could also be affected by other factors, such as the vertical homogeneity of the sediments. [ABSTRACT FROM AUTHOR]

ABSTRACT Yuhi, M. and Umeda, S., 2018. Characteristics of systematic migrations of multiple sandbars and related cross-shore sediment transport at Chirihama and adjacent coasts, Japan. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 231–235. Coconut Creek (Florida), ISSN 0749-0208. Characteristics of systematic migration of multiple bar system on the Chirihama and adjacent coasts, Japan, have been investigated based on a set of annual field surveys collected over 11 years. The morphological variations were first separated into time-averaged profiles and deviation components. An EOF analysis was conducted on the deviation components in order to extract the principal modes of periodic bar migration. The migration cycle consisting of generation, migration and degeneration were well reproduced by the combination of first and second modes. The cross-shore sediment transport and sediment volume variation related to bar migration were then examined. An integration of the equation for sediment volume conservation revealed that the principal modes of cross-shore sediment transport was characterized by the spatial integration of spatial eigen-functions and the temporal derivative of the temporal eigen-functions. Corresponding to the cyclic behaviors of sandbar system, the direction of sediment transport changed alternatively between seaward and landward directions. On short-term, cyclic exchange of sediment occurred between the bar migration zone and foreshore, but on long-term the principal modes of bar migration made little contribution to overall sediment volume variation. [ABSTRACT FROM AUTHOR]

Gully erosion is a global problem that degrades land and reduces its utility for agriculture, development, and water quality. Quantification of sediment yield and control of sediment sources is essential for environmental protection. Five methods to evaluate erosion rates and sediment yield on an east Tennessee, USA, hillslope were compared: (1) physical measurement by removal of accumulated sediment using 10 L buckets; (2) repeated measurement of erosion pins in gully (erosional) and delta (depositional) areas; (3) geometric model using a combination trapezoidal prism-cylinder segment; (4) geometric model using a series of trapezoidal pyramids; and (5) 3D solid computer modeling. The 3D solid model created in SolidWorks was selected as the reference model and all other methods overestimated sediment yield to varying degrees. Erosion pin methods overestimated sediment yield by 368% in deltas and 123% in gullies. Volumetric measurement of sediment using buckets overestimated sediment yield by 160% due to void space in the buckets. The trapezoidal prism-cylinder segment model overestimated sediment yield by 66% and the trapezoidal pyramids method overestimated sediment yield by 5.7%. For estimation of sediment trapped behind an elliptical or circular silt fence dam, use of the trapezoidal pyramid method provides a good approximation comparable to 3D solid computer modeling. [ABSTRACT FROM AUTHOR]

This study investigates the combined performance of ground rubber (GR), the additive, and polyacrylamide (PAM), the binder, as a sustainable solution towards ameliorating the inferior geotechnical attributes of an expansive clay. The first phase of the experimental program examined the effects of PAM concentration on the soil’s mechanical properties—consistency, sediment volume attributes, compactability, unconfined compressive strength (UCS), reactivity and microstructure features. The second phase investigated the effects of GR content, with and without the optimum PAM concentration. An increase in PAM beyond 0.2 g/L, the identified optimum concentration, caused the excess PAM to act as a lubricant rather than a flocculant. This feature facilitated reduced overall resistance to sliding of soil particles relative to each other, thereby adversely influencing the improvement in stress−strain−strength response achieved for ≤0.2 g/L PAM. This transitional mechanism was further verified by the consistency limits and sediment volume properties, both of which exhibited only minor variations beyond 0.2 g/L PAM. The greater the GR content, the higher the mobilized UCS up to 10% GR, beyond which the dominant GR-to-GR interaction (i.e., rubber-clustering) adversely influenced the stress−strain−strength response. Reduction in the soil’s swell−shrink capacity, however, was consistently in favor of higher GR contents. Addition of PAM to the GR-blended samples amended the soil aggregate−GR connection interface, thereby achieving further improvements in the soil’s UCS and volume change behaviors. A maximum GR content of 20%, paired with 0.2 g/L PAM, managed to satisfy a major decrease in the swell−shrink capacity while improving the strength-related features, and thus was deemed as the optimum choice.

Traits related to seed quality have an important role in production of durum wheat. To estimate the heritability of protein content, semolina content, Zeleny number, seed hardness, SDS, dry and fresh gluten content, gluten index, and also to investigate the relationship of these traits in durum wheat, a recombinant inbred lines (RILs) population including 94 recombinant inbred lines (F10), two parents (Ac. Navigator and G9580B-FE1C) and four controls (Diper, Preion and PI10235 varieties and a local variety “Ajr”) were evaluated. This experiment was carried out in the Research Farm of Shahrekord University, Shahrekord, Iran, using a triple lattice design.. Results showed that frequency distribution for gluten index was bimodal and for the rest of the traits was normal. This indicated the two-genes control and quantitative inheritance of these traits in the population,respectively. Transgressive segregation was observed for all the traits. The calculated heritability for protein content, seed hardness, SDS and semolina content was in the low range of 11.4-24.7%. For fresh and dry gluten and Zeleny number, it was 45, 36.2 and 37.1%, respectively. For gluten index, it was high (76.6%). The genetic correlation coefficient between protein content and Zeleny number was positive and high (r= 0.98), which indicates the suitability of this trait as a criterion for protein content. The results of path analysis for semolina, as the main feature in pasta production, based on genetic correlation coefficients, showed that the highest negative direct effect was related to Zeleny number the highest positive effect was related to protein content, which indicated the importance of these traits in explaining the semolina yield.

Gully erosion is a global problem that degrades land and reduces its utility for agriculture, development, and water quality. Quantification of sediment yield and control of sediment sources is essential for environmental protection. Five methods to evaluate erosion rates and sediment yield on an east Tennessee, USA, hillslope were compared: (1) physical measurement by removal of accumulated sediment using 10 L buckets; (2) repeated measurement of erosion pins in gully (erosional) and delta (depositional) areas; (3) geometric model using a combination trapezoidal prism-cylinder segment; (4) geometric model using a series of trapezoidal pyramids; and (5) 3D solid computer modeling. The 3D solid model created in SolidWorks was selected as the reference model and all other methods overestimated sediment yield to varying degrees. Erosion pin methods overestimated sediment yield by 368% in deltas and 123% in gullies. Volumetric measurement of sediment using buckets overestimated sediment yield by 160% due to void space in the buckets. The trapezoidal prism-cylinder segment model overestimated sediment yield by 66% and the trapezoidal pyramids method overestimated sediment yield by 5.7%. For estimation of sediment trapped behind an elliptical or circular silt fence dam, use of the trapezoidal pyramid method provides a good approximation comparable to 3D solid computer modeling.

The morphological evolution of the Barents-Kara Shelf is a graphic example of how erosion and glaciation reshape the Earth's surface. Decades of petroleum exploration sparked longstanding debates on the shelf's obscured Cenozoic history. As a result, the Barents-Kara shelf has almost become a benchmark of erosion models and techniques. Several studies along the edges of the Barents shelf focus on the local relationship between sediments accumulated off-shelf and the amount of erosion in the adjacent areas. However, there are no studies of the entire Barents-Kara region. To address this issue and test the regional estimations of erosion, we first compiled an up-to-date map of erosional products accumulated off-shelf and separated them into Quaternary (glacial) and pre-glacial successions. Mass balance between erosion and sedimentation coupled with numerical analysis of morphology of the Barents-Kara realm demonstrates that the dominant part of Quaternary erosion is expressed within modern cross-shelf troughs and fjords. This analysis also shows that at the beginning of the Quaternary the shelf was submarine, with average water depths of ca. 40–90 m. Using recently acquired borehole data and published thermo-chronological and morphological studies, we developed a new map of Cenozoic erosion of the Barents-Kara shelf. The predicted erosion of our new model is smaller than previously published. However, even reduced, our estimate of erosion volume is almost 50 % larger than the amount of off-shelf sediment. Generally, sub-sea erosion estimates are based on seismic methods and well logs reflecting compaction of sedimentary rocks caused by (now partly removed) load from above. This missing load, however, may comprise not only erosion, but also glaciation, as the shelf was repeatedly covered by thick ice caps. A reduction of erosional estimates by accounting for ice load may provide a balance between accumulated sediments and erosion estimates. [Display omitted] • Off-shelf sediment and erosion estimates do not balance for the Barents-Kara shelf. • Reconstruction of pre-glacial shelf requires 20 % more glacial off-shelf sediments. • Total Cenozoic erosion volume is 50 % larger than the volume of off-shelf sediments. • Traditional techniques of erosion estimates may fail in the Barents-Kara shelf. • Ice load on the strata could explain misinterpretation of compaction trends. [ABSTRACT FROM AUTHOR]

The ease with which water is released from cellulosic fiber material during the manufacturing of paper can affect both the production rate and the consumption of energy during the manufacturing process. Important theoretical contributions to dewatering phenomena have been based on flow through packed beds of uniformly distributed fibers. Such descriptions are able to explain why resistance to dewatering increases as a function of the hydrodynamic surface area of fibers. More recent studies have demonstrated a critical role of finely divided matter. If the fines are unattached to fibers, then they tend to move freely through the fiber mat and plug channels in the paper web during the dewatering process. Dewatering also is affected by the deformability of cellulosic fibers and by whether the fibers easily slide past each other, thereby forming a dense mat. By emphasizing the role of fine matter, colloidal forces, and conformability of cellulosic materials, one can gain a more realistic understanding of strategies that papermakers use to enhance initial drainage and vacuum-induced dewatering.

This study ascertains landslide impact under climate change. The disaster impact under climate change was estimated by calculating the variation in safety factor (FS value). The result shows less landslide impact for the late 21st century (2075 - 2099) than in the late 20th century (1979 - 2003). The relationship between rainfall characteristics and landslide susceptibility was then clarified. A total of 40 out of 82 typhoon events from the late 20th century and 40 out of 88 events from the late 21st century were selected for estimating landslide impact. The landslide ratio in each event is calculated to find the variation in landslide occurrence between the late 20th and the late 21st century. The result proved that landslide occurrence is highly dependent on the rainfall characteristics. Landslides occurred earlier during each rainfall event for the late 21st century, which is consistent with rainfall characteristics, e.g., high intensity and short duration, for the late 21st century. [ABSTRACT FROM AUTHOR]

Glaciers in alpine mountains create special landforms that store large amounts of sediment, providing loose materials for debris flows. Various types of catchments have diverse storage modes for such materials, resulting in differences in the location and volume of sediment. However, little is known about this phenomenon due to the lack of data. Hence, taking the Parlung Zangbo basin as an example, we identify the main sediment according to the catchment type and propose sediment calculation methods for different types. The results show that tributary catchments can be divided into five types: deep U-shaped catchments, shallow U-shaped catchments, glacial hanging catchments, fluvial catchments after glaciation, and fluvial catchments. The sediments include glacial deposits, landslides, talus slopes, fans, etc. Non-glacial sediments can be calculated by the morphological method, while the thickness of glacial deposits can be calculated effectively by the proposed curve-fitting method. The volumes of glacial deposits are obtained and compared with those of other sediments. Glacial deposits are one or two orders of magnitude larger than other deposits. Glacial deposits in the first three types are concentrated on gentle downstream slopes, while in the fourth type was in steep location. • The tributaries of the Parlung Zangbo Basin are divided into five types by principal component analysis. • The curve-fitting method can get an accurate accumulation thickness of glacial valley. • Channel deposits are one or two orders of magnitude larger than other deposits [ABSTRACT FROM AUTHOR]

• A UAV-based method estimating sediment deposited behind check dams was developed. • Errors of the optimal model for single and regional check dams are 12–13% and 2–3%. • This method avoids limitations of tedious field surveys and historical records. • This method can evaluate sediment retained by check dams in areas as large as 211,800 km2. The estimation of sediment deposited behind dams and reservoirs is of great significance for quantifying soil erosion rate and sediment flux. However, existing methods of sediment volume estimation often require detailed field measurements and historical topographic data, limiting the broader application of these methods. In this paper, focusing on the region that suffers the world's most severe soil erosion, we combine unmanned aerial vehicle (UAV) photogrammetry and simulate submerging analysis to propose a novel method for estimating sediment silted by check dams under complex topography. We obtained 1339 groups of topographic factors and ascertained the corresponding volumes of sediment deposited behind check dams in the loess hilly region of China (LHRC), and established five different models combined with regression analysis. Two different sets of data were used for method validation and optimal model determination. The results showed that the error of the optimal model in the volume estimation of single check dam and regional check dams is 12–13% and 2–3%, respectively. Additionally, the area-volume model has the potential to evaluate the sediment retention capacity of check dams (in the order of billions of cubic meters) in the whole LHRC, because the variables are easy to obtain and the model accuracy is relatively high. The further application of this method will help to evaluate the watershed sediment yield and regional soil and water conservation benefits, and is of great significance for explaining the future changes in water and sediment in the Yellow River basin. [ABSTRACT FROM AUTHOR]