Transport Patterns Research Articles

Assessing the impact of mining on cyclic and linear methylsiloxane distribution in Tibetan soils: Source contribution and transport pattern

The pervasive presence of methylsiloxanes (MSs), comprising linear and cyclic congeners, in the environment poses significant ecological risks, yet the understanding of their transport mechanisms and deposition patterns remains limited. This study analyzed the concentrations of 12 linear-MSs (L3–L14) and 7 cyclic-MSs (D3–D9) in 29 surface soil samples collected across varying altitudes (3726 to 4863 m) near the Jiama mining sector in Tibet, aiming to investigate the distribution and transport dynamics of MSs from the emission source. The distribution of total MS concentration (ranging from 50.1 to 593 ng/g) showed a remarkable correlation with proximity to the mining site, suggesting the emergent source of mining activities for the MSs in the remote environment of the Tibetan Plateau. Employing the innovative model of robust absolute principal component scores-robust geographically weighted regression (RAPCS-RGWR), the analysis predicted that the mining operations contributing 57.1 % of the total soil MSs, would significantly surpass contributions from traffic emissions (14.7 %), residential activities (13.2 %), and the environmental factor of total organic matter content (14.9 %). The Boltzmann equation effectively modeled the distribution pattern of soil MSs, highlighting atmospheric transport and gravitational settling as key distribution mechanisms. However, linear-MSs exhibited longer transport distances than cyclic-MSs and were more profoundly affected by prevailing wind directions, suggesting their differential environmental behaviors and risks. Our study underscored that the mining sector possibly emerged as a significant source of Tibetan MSs, and provided insights into the transport and fate of MSs in remote, high-altitude environments. The findings emphasize the need for targeted pollution control strategies to mitigate the environmental footprint of mining activities in Tibet and similar regions.

Research on the competitiveness of the Arctic transportation route under the belt and road initiative

AbstractWith the continuous improvement of the navigation environment of the Arctic routes, the commercialization potential of the Arctic routes is enhanced, which brings new challenges to the Suez Canal route and the China–Europe railway Express. In addition, geopolitical factors such as the Russia–Ukraine conflict and the Red Sea crisis have also brought some impact on the Eurasian transport pattern. In this context, the future trade and transportation between China and Europe will take on a new pattern. In order to study the transport competition pattern between China and Europe under the opening of the Arctic routes, this article takes into account the time‐value cost of goods and geopolitical factors, constructs a logit competition model, and quantitatively investigates the competitiveness of the Arctic route and the traditional routes of the “Belt and Road Initiative” using major international transportation hub cities in China. The results show that the types of cargo and the level of freight are important factors affecting the competitiveness of Arctic routes. Under the influence of geopolitics, the competitive advantage of the Arctic routes are highlighted.

Numerical simulation of heavy metal migration in stabilized soils under multi-field coupling

Heavy metal contamination of soils has become a global issue. In pursuit of a reference for the management of heavy metal pollution, numerical simulations were used here to investigate the migration pattern of heavy metals in soil under multi-field coupling of rainfall, temperature, and hydraulic conductivity. Models were built using TOUGHREACT, and measured and simulated values were compared with those of existing studies to verify the accuracy of the software in simulating coupled water vapor-thermal transport and rainfall infiltration. Taking Nanjing rainfall data as an example, the transport pattern of zinc in soil under multi-field coupling was explored. Although evaporation and rainwater infiltration were found to increase with the temperature, the effects of evaporation and temperature counteracted each other, resulting in a weak influence of temperature on heavy metal transport. The hydraulic conductivity of stabilized soil was the main factor controlling zinc migration, with the saturation and heavy metal concentration clouds of soil columns tending to stabilize when the hydraulic conductivity of solidified soil was under 1 × 10-11 m/s.

Holocene sedimentary distribution and morphological characteristics reworked by East Asian monsoon dynamics in the Mekong River shelf, South Vietnam

The distribution of Holocene sediments in the Mekong River shelf area was investigated using shallow seismic and core data. The results show that the shelf depositional stratigraphy since the last glacial period can be classified into four depositional units (U1, U2, U3 and U4). The average thickness of the Holocene deposit in the nearshore area of the Mekong River estuary is approximately 20 m and decreases seaward. In addition to a thickened deposit in the palaeo-river channel, two sedimentary centres have developed, namely, the Mekong River estuary and the Cape Ca Mau area. In contrast to nearshore deposition, the Holocene sedimentation rate rapidly decreased offshore, even in the transgressive systems tract. To understand the driving mechanisms for the variation in Holocene deposition, a three-dimensional numerical model and Geographic Information System(GIS)-based model were applied to reconstruct the oceanographic and sediment transport patterns on the South Vietnam shelf. The simulation results reveal that the Mekong River shelf has undergone significant transformations since the Last Glacial Maximum (LGM). During the LGM, the coastline was situated near the shelf break, and as the sea level rose rapidly, the shoreline retreated. When the sea level reached its peak, the modern Mekong Delta emerged. Furthermore, the distribution of Holocene deposits is controlled by monsoon-influenced seasonal variations in currents, resulting in a triangular delta and narrow strip-like subaqueous clinoform. Our simulation results also show obvious erosional capacity in the offshore area, leading to an evident erosional through to the east of Cape Ca Mau and erosion of Pleistocene sediments in the shelf break area. By combining stratigraphic interpretation and oceanographic simulations, our study provides new insights into sediment transport and erosion processes mediated by ocean currents driven by East Asian monsoons.

Integrated optimization of production planning and electric trucks charging and discharging scheduling

The majority of supply chains in any manufacturing industry rely on heavy trucks for their flow of material from suppliers to end-users. Transportation by these heavy trucks causes greenhouse gas emissions detrimental to the environment. To cope with challenges caused by environmental issues and energy crises, replacing heavy trucks with electric trucks seems to be a viable solution. They can be considered as an energy resource that supports grid-to-vehicle and vehicle-to-grid, enabling efficient energy management for smart manufacturing systems and supply chains. Proper scheduling of charging and discharging activities of electric trucks also supports the penetration of renewable energy sources with volatile energy generation. This paper encourages sustainable practices and proposes a mixed integer programming model for the simultaneous optimization of production planning and transportation scheduling of electric trucks in a smart manufacturing system. The uncertainty sources considered in this system include power generation of renewable energy, transportation patterns, and customer demand for products. The results show that utilizing electric trucks in smart manufacturing with real-time pricing, save up to 11% of the total cost compared to traditional manufacturing systems without electric trucks and renewable energies. This integration also increases the efficient utilization of renewable energies such as wind and solar powers. The savings decrease to 4% and 8% under flat and time-of-use electricity pricing strategies. The results also highlight the complexity of setting utilization level of electric trucks and renewable energy sources into well-implemented sustainability standards.

AGENT-BASED MODELING OF UP DILIMAN INTRACAMPUS PEDESTRIAN MOBILITY USING NETLOGO AND GIS

Abstract. In the Philippines, campus mobility studies remain underexplored. Since small-scale models help in policy making that may also be applied in a large spatiotemporal context, intracampus mobility modeling and simulation offer support for future mobility research. In this study, we designed a NetLogo model to apply ABM and GIS in understanding intracampus student pedestrian mobility. We created a deterministic model using discrete student schedule and a probabilistic model using the multinomial logistic (MNL) regression model derived from the student demographics data to analyze student movement. To provide a realistic representation of student pedestrians and campus environment, GIS spatiotemporal data was proven crucial to the pedestrian mobility models. The generated pedestrian count heatmaps show a significant increase in student count from online learning switching to face–to–face instruction. The overall campus building occupancy served as the key factor influencing the changes in agent behaviors such as walking speed and student tardiness. Moreover, the probabilistic model showed erratic movements of students. The model evaluation depends on the heavily imbalanced datasets and its multiclass nature with relatively higher model performance (F1 score > 0.8) is observed during morning, noon, and end schedule times, whereas suboptimal performance (F1 score < 0.6) where the dataset has a higher number of classes. The simulations demonstrate that ABM is a useful tool for examining pedestrian and transport patterns and can be enhanced further to allow multimodal and multiagent systems.

Understanding the removal of heavy metals from stormwater runoff in permeable pavement system

Understanding the removal of heavy metals (HMs) in permeable pavement systems is of great significance for controlling urban runoff pollution and optimizing structural design. However, few studies have systematically investigated the mechanism of permeable pavement systems in removing HMs from stormwater runoff. In this study, we adopted a hierarchical strategy to understand the efficiency of individual structural layers on HMs removal in a permeable interlocking concrete pavement (PICP) system. Experimental results illuminated that the surface layer exhibited the highest uptakes of HMs, which can remove up to 64 % of Pb2+, 50 % of Cu2+, 28 % of Cd2+ and 13 % of Zn2+. Meanwhile, as the rainfall return period increased, the removal rates of HMs in PICP was gradually decreased. In addition, batch experiments were conducted and the adsorption results were in accordance with the rainfall filtration experiments. More importantly, X-ray Photoelectron Spectroscopy (XPS) and leaching results were investigated to understand the HMs removal mechanism, which found that the ion exchange is the main mechanism in the surface layer to remove HMs, whereas the chemical adsorption play a crucial role in the base and sub-base layers. Overall, these findings provided new insights into the transport patterns of HMs in the internal structural layers of the PICP.

Extraction of persistent lagrangian coherent structures for the pollutant transport prediction in the Bay of Bengal

Lagrangian Coherent Structures (LCS) are the hidden fluid flow skeletons that provide meaningful information about the Lagrangian circulation. In this study, we computed the monthly climatological LCSs (cLCS) maps utilizing 24 years (1994–2017) of HYbrid Coordinate Ocean Model (HYCOM) currents and ECMWF re-analysis winds in the Bay of Bengal (BoB). The seasonal reversal of winds and associated reversal of currents makes the BoB dynamic. Therefore, we primarily aim to reveal the cLCSs associated with seasonal monsoon currents and mesoscale (eddies) processes over BoB. The simulated cLCS were augmented with the complex empirical orthogonal functions to confirm the dominant lagrangian transport pattern features better. The constructed cLCS patterns show a seasonal accumulation zone and the transport pattern of freshwater plumes along the coastal region of the BoB. We further validated with the satellite imagery of real-time oil spill dispersion and modelled oil spill trajectories that match well with the LCS patterns. In addition, the application of cLCSs to study the transport of hypothetical oil spills occurring at one of the active oil exploration sites (Krishna-Godavari basin) was described. Thus, demonstrated the accumulation zones in the BoB and confirmed that the persistent monthly cLCS maps are reasonably performing well for the trajectory prediction of pollutants such as oil spills. These maps will help to initiate mitigation measures in case of any occurrence of oil spills in the future.

Sediment resuspension and transport due to synoptic winter winds in the Bohai Sea

The Bohai Sea is the receiving basin of the Yellow River (Huanghe), one of the largest contributors of global terrestrial materials to the sea. An area of fine-grained sediment deposition extends northeast of the Yellow River and its formation mechanism is still unclear. A calibrated, high-resolution coupled model of the Bohai and Yellow Seas was used to investigate sediment transport pathways in the region under the influence of strong and varying winds in winter. Numerical results highlight the importance of storm events in modifying the regional sediment resuspension and transport. During winter, the prevailing winds are typically from the northeast and northwest, interspersed by relaxation periods with weak winds. Winds influenced the currents and sediment movement in the Bohai Sea through several processes: local wind waves and resuspension, coastal-trapped waves in the Bohai Sea, and remotely forced coastal-trapped waves in the Yellow Sea. During northwesterly winds, sediment off the Yellow River Delta was mainly transported eastward along the south coast of Bohai Sea and escaped the Bohai Sea through the southern Bohai Strait. When northeasterly winds prevailed, sediment transport split into three branches: westward into the Bohai Bay, northeastward to the central Bohai Sea, and eastward along the south coast of Bohai Sea. Modeling results driven by synoptic winds indicate a more complex sediment transport pattern than previously understood with monthly average wind forcing. These findings challenge the traditional view of predominantly eastward sediment transport during winter and help to explain the observed grain size distribution in the Bohai Sea, in particular the accumulation of fine-grained sediments northeast of the Yellow River.

Pebble tracing experiment at the Promenade des Anglais (Nice, France): A contribution towards beach management efforts

In this paper, the results of a short-term tracing experiment carried out at a beach compartment along the Bay of Nice (southern France) are presented. Nice urban beach is characterized by persistent offshore sediment loss issues that force the local administration to operate frequent artificial replenishments to maintain the current configuration, which also protects the well-renown Promenade des Anglais from high-energy events. As beach refills are quite expensive, the aim of the paper is to provide novel insights about the transport processes of pebble-sized tracers, which might support the Municipality to better adjust future interventions. Pebbles were tracked by means of the Radio Frequency Identification technology, largely used in such settings because of its reliability and efficiency. In addition, the morphology of the beach was monitored during the three-days-long experiment by airborne and ground topographic surveys, as well as the shape and the size of the tracers. Finally, a wave model was produced to simulate wave propagation in the nearshore, which validates the observed transport patterns. The results documented a low recovery rate (56%) 4 h after tracer injection, which is uncharacteristic considering that it jumped to 91% after the second survey, 24 h after the injection. At the end of the experiment (48 h), the recovery rate sank to 14%. These data were adequate to identify a few trends in pebble transport: tracer recovery rate in the swash zone was very low, while many marked pebbles were found at the step crest. Although this transport pattern may corroborate the offshore movement of the sediments, the topographic surveys revealed the destruction and re-formation of the fair-weather berm overnight, which would imply the presence of a shoreward transport under low energy wave conditions. While size did not single out any tendency, shape did: spheres rolled down the beachface earlier than disks; by contrast, disk-shaped pebbles moved for longer distances than spheres. These findings will be useful for local coastal managers because next beach fills will be planned and optimized based on the observed transport patterns. Though the selection of disk-shaped pebbles implies increasing costs, replenishments would be more efficient and fine-tuned for this sector of coast, which would ultimately save resources reducing negative impacts on the environment along the way. These considerations are valid for the Bay of Nice, but they might be useful wherever coarse-clastic beaches need recurring replenishments.

Soil structure and solute transport pathways in biogas digestate-amended soils

Here, we investigated the effects of biogas digestate application on flow pathways and soil properties in a sandy soil aiming at unraveling phosphorus accumulation and depletion processes in fertilized soils. Dye tracer experiments were conducted to visualize and distinguish between various flow pathways, while X-ray tomography was utilized to characterize the soil structure. The dye tracer experiments revealed differences between the control and the digestate-treated group of soil profiles in the top-soils although no statistical verification was possible amid a single plot per treatment. The stained soil profiles in both treatments indicate extensive areas of homogeneous and heterogeneous matrix flow. However, the digestate-treated group showed a decrease in homogeneous matrix flow and a notable presence of preferential flow with low interaction. The application of biogas digestate impacted various soil properties, including organic carbon content, water drop penetration time, and pH levels. Accordingly, the topsoil experienced an increase in soil organic carbon, water repellency, and a decrease in pH levels. The fraction of macropores also increased in the topsoil of the digestate-treated group, accompanied by an increase in tortuosity.Double lactate-extractable phosphorus (DL-P) distribution varied across the different flow pathways, with higher concentrations detected in matrix flow and a depletion observed in preferential flow regions in both treatments. These findings confirm the close relationship between the type of flow pathway and phosphorus distribution in soils. Additionally, a significant correlation was observed between pH levels and DL-P in the digestate-treated group, indicating potential implications for phosphorus availability. Overall, the results of this study suggest that the long-term application of biogas digestate is likely to improve soil properties as related to soil organic matter content, particularly in the topsoil of sandy soils. The study highlights the significance of the prevailing flow and transport pattern on nutrient distribution, with potential implications for nutrient management in agricultural systems. While the study design presented prevents the unequivocal assignment of differences to treatment effects, our data likely illustrate the impacts of biogas digestate amendment on the investigated sandy soil.Further research should focus on assessing the long-term effects of digestate application in loamy and clayey soils.

Recapitulation of native human expression patterns of key transport and drug metabolism genes in an in vitro human donor-derived intestinal epithelium

Recapitulation of native human expression patterns of key transport and drug metabolism genes in an in vitro human donor-derived intestinal epithelium

A Global Assessment of Eddy‐Induced Salinity Anomalies and Salt Transport by Eddy Movement

AbstractEddy‐induced salt transport is essential in maintaining the oceanic salinity balance and global climate. However, the paucity of in situ measurements poses challenges in obtaining the spatial structure of the eddy salt transport globally. Here, we conduct a global estimation of eddy‐induced salinity anomalies and salt transport by eddy movement using 2 million historical hydrographic profile measurements and satellite‐based eddy observations spanning from 1993 to 2019. The results demonstrate rich geographic and vertical variability in the salinity anomalies induced by eddies across the global ocean. Vertical sign switches of salinity anomalies within eddies are observed in the tropical and subtropical oceans, as well as in the Kuroshio Extension region. Additionally, meridional sign switches of eddy‐induced salinity anomalies are observed in the Antarctic Circumpolar Current region. By integrating eddy occurrence probability, we refine the methodology for estimating eddy‐induced salt transport, and provide global spatial patterns of both meridional and zonal salt transport induced by eddy movement at each 2° × 2° grid. Significant salt transport by meridional eddy movement is observed in the mid‐latitude oceans, with the peak zonal‐depth integrated salt transport reaching 106 kg·s−1 in the mid‐latitudes of the southern hemisphere. Specifically, the Brazil‐Malvinas Confluence region is identified as a highly efficient pathway for meridional salt transport, with a magnitude of −1.28 × 106 kg·s−1, significantly surpassing other regions in the global ocean. These findings may provide important references for the understanding and simulation of global oceanic salinity transport.

Electro-osmotic transport and thermal energy dynamics of tetra-hybrid nano fluid in complex peristaltic flows

BackgroundThis study explores the use of tetra-hybrid nanoparticles consisting of gold, silver, alumina, and titania nanocomposites dispersed in a non-Newtonian Casson fluid modelled as blood. The motivation lies in harnessing the synergistic optical, electrical, thermal, and physicochemical properties of the multimodal nanoscale assembly to advance electrokinetic pumping processes. ObjectivesThe study aims to computationally investigate the complex transport assisted by tailored gold, silver, alumina, and titania dioxide nanoparticles in the tetra-hybrid nanofluid, with potential applications in targeted drug delivery, hyperthermia cancer treatment, Lab-on-Chip devices, and miniaturized biosensors. MethodologyThe constructed streaming flow model examines the cumulative influence of viscous heating, Joule heating, conductive thermal, and external laser irradiation. Current simulations examine Casson flows with the integrated nanoparticles by modelling two- and three-dimensional conduits subject to transverse magnetohydrodynamics and localized laser irradiation. Key findingsThe solutions provide mathematical predictions and physical insights into the fully coupled velocity, temperature, concentration, and pressure gradient contours. Additional plots examining dimensionless analytes against pertinent profiles, combined with streamlined visualization, further elucidate the multifaceted transport and complex trapping patterns stemming from non-Newtonian rheology. Applications/implicationsThis multiscale examination reveals performance improvements realizable by leveraging biocompatible tetra-hybrid nanocomposites in electrokinetic flows vital for next-generation biomedical technologies.

Timing of emergency medical services activations for falls

ObjectiveFalls are a major challenge to public health, particularly among older adults. Understanding factors that influence fall risk is pivotal in the prevention of falls and fall-related injuries. This study evaluated the timing of emergency medical service (EMS) activations for falls and transport patterns for adults age ≥65. MethodsA patient care report system at a single fire-based emergency medical service agency in a suburban, Midwest city was retrospectively reviewed. Type of call (lift assist/fall), time of injury (time, day, and month), and demographics (sex, age) were collected for residents age ≥65 who activated 9–1–1 for a lift assist or fall. Results1169 calls met inclusion criteria. Mornings and afternoons were the time of day associated with falls (33 % and 36 % of EMS activations, respectively, vs. 21 % and 10 % for evenings and nights, respectively; p = 0.002) while day of the week and month were not associated with falls or lift assists. More males requested lift assists than females (256 vs. 238) and more females called for falls than males (408 vs. 267; p < 0.001). Falls were more likely to be associated with transport to the hospital than lift assists (78% vs. 7 %). Female sex was associated with increased risk for transport to the hospital (60 % of females vs. 40 % of males; p < 0.001). ConclusionsMornings and afternoons were associated with increased risk for falls and sex (female) with increased risk for transport to the hospital.

A data-driven framework for natural feature profile of public transport ridership: Insights from Suzhou and Lianyungang, China

Urban public transport systems, characterised by their complexity, generate vast data sets that pose challenges to traditional analytical methods. To address this issue, our research introduces an innovative natural feature profile framework, leveraging a comprehensive, data-driven approach that incorporates big data, data mining, machine learning, and correlation analysis. This approach provides detailed insights essential for transport planning and policy development. The framework's core is its three-layered structure: the data layer, the feature layer, and the application layer, complemented by a unique four-level feature tagging system. This system investigates correlations, significance, and sensitivities amongst feature tags. It facilitates the extraction of natural feature profiles from voluminous data sets, rendering the framework highly applicable in practical scenarios. The implementation of this framework in Suzhou and Lianyungang demonstrated its adaptability and effectiveness. The findings underscored distinct city-specific transport patterns, highlighting the necessity for customised transport strategies. Furthermore, our framework excels at capturing spatial–temporal dynamics, offering essential insights grounded in evidence. Overall, this paper introduces a methodical, adaptable, and data-oriented framework, signalling a promising future for the development of intelligent and sustainable urban public transport systems.

Phosphate and illite colloid pose a synergistic risk of enhanced uranium transport in groundwater: A challenge for phosphate immobilization remediation of uranium contaminated environmental water

The phosphorus-containing reagents have been proposed to remediate the uranium contaminated sites due to the formation of insoluble uranyl phosphate mineralization products. However, the colloids, including both pseudo and intrinsic uranium colloids, could disturb the environmental fate of uranium due to its nonnegligible mobility. In this work, the transport pattern and micro-mechanism of uranium coupled to phosphate and illite colloid (IC) were investigated by combining column experiments and micro-spectroscopic evidences. Results showed that uranium transport was facilitated in granular media by forming the intrinsic uranyl phosphate colloid (such as Na-autunite) when the pH > 3.5 and CNa+ < 10 mM. Meanwhile, the mobility of uranium depended greatly on the typical water chemistry parameters governing the aggregation and deposit of intrinsic uranium colloids. However, the attachment of phosphate on illite granule increased the repulsive force and enhanced the dispersion stability of IC in the IC-U(VI)-phosphate ternary system. The non-preequilibrium transport and retention profiles, HRTEM-mapping, as well as TRLFS spectra revealed that the IC enhanced uranium mobility by forming the ternary IC-uranyl phosphate hybrid, and acted as the coagulation preventing agent for uranyl phosphate particles. This observed facilitation of uranium transport resulted from the formation of intrinsic uranyl phosphate colloids and IC-uranyl phosphate hybrids should be taken into consideration when evaluating the potential risk of uranium migration and optimizing the in-situ mineralization remediation strategy for uranium contaminated environmental water.

Quantifying the role of submesoscale Lagrangian transport features in the concentration of phytoplankton in a coastal system

Abstract Food resources in the ocean are often found in low densities, and need to be concentrated for efficient consumption. This is done in part by oceanographic features transporting and locally concentrating plankton, creating a highly patchy resource. Lagrangian approaches applied to ocean dynamics can identify these transport features, linking Lagrangian transport and spatial ecology. However, little is known about how Lagrangian approaches perform in ageostrophic coastal flows. This study evaluates two Lagrangian Coherent Structure metrics against the distribution of phytoplankton; Finite Time Lyapunov Exponents (FTLE) and Relative Particle Density (RPD). FTLE and RPD are applied to High Frequency Radar (HFR) observed surface currents within a biological hotspot, Palmer Deep Canyon Antarctica. FTLE and RPD identify different transport patterns, with RPD mapping single particle trajectories and FTLE tracking relative motion of paired particles. Simultaneous measurements of circulation and phytoplankton were gathered through the integration of vessel and autonomous glider surveys within the HFR footprint. Results show FTLE better defined phytoplankton patches compared to RPD, with the strongest associations occurring in stratified conditions, suggesting that phytoplankton congregate along FTLE ridges in coastal flows. This quantified relationship between circulation and phytoplankton patches emphasizes the role of transport in the maintenance of coastal food webs.

Net Transport Patterns of Surficial Marine Sediments in the North Aegean Sea, Greece

The spatial distribution of sediments on the seafloor reflects the various dynamic processes involved in the marine realm. To analyze sediment transport patterns in the North Aegean Sea, 323 surficial samples were obtained and studied. The granulometry data revealed a diverse range of grain sizes of surficial sediments, ranging from purely sandy to clay. The predominant size classes were silt and muddy sand, followed by sandy silt and mud. However, there were very few samples that fell within the clay classes. The sorting coefficient ranged from 0.21 to 5.48, while skewness ranged from −1.09 to 1.29. The sediment transport patterns were analyzed based on the grain-size parameters (mean, sorting, and skewness). The results showed the variability of flow parameters involved in sediment distribution. River influx and longshore drift near the shoreline are the most significant factors affecting sediment transport. At the open sea, sediment distribution is mainly controlled by general water circulation patterns, especially by the outflow of low-salinity waters from the Black Sea through the Dardanelles and the Marmara Sea. The heterogeneity of sediment textural parameters across the study area suggests that seafloor sediments are further reworked in areas where water masses are highly energetic. It can be concluded that open sea water circulation controls sediment distribution patterns at the open shelf, while close to the coast, river discharge plays a key role.

Identification and Expression Analysis of Putative Sugar Transporter Gene Family during Bulb Formation in Lilies.

Sugar transporters play important roles in plant growth and development, flowering and fruiting, as well as responses to adverse abiotic and biotic environmental conditions. Lilies (Lilium spp.) are some of the most representative ornamental bulbous flowers. Sugar metabolism is critical for bulb formation in lilies; therefore, clarifying the amount and expression pattern of sugar transporters is essential for further analyzing their roles in bulb formation. In this study, based on the transcriptome data of the Lilium Oriental hybrid 'Sorbonne' and Lilium × formolongi, a total of 69 and 41 sugar transporters were identified in 'Sorbonne' and Lilium × formolongi, respectively, by performing bioinformatics analysis. Through phylogenetic analysis, monosaccharide transporters (MSTs) can be divided into seven subfamilies, sucrose transporters (SUTs) can be divided into three subgroups, and sugars will eventually be exported transporters (SWEETs) can be divided into four clades. According to an analysis of conserved motifs, 20, 14, and 12 conserved motifs were predicted in MSTs, SUTs, and SWEETs, respectively. A conserved domain analysis showed that MSTs and SUTs contained a single domain, whereas most of the SWEETs harbored two MtN3/saliva domains, also known as a PQ-loop repeat. The LohINT1, which was predicted to have a smaller number of transmembrane structural domains, was cloned and analyzed for subcellular localization. It was found that the LohINT1 protein is mainly localized in the cell membrane. In addition, the expression analysis indicated that 22 LohMSTs, 1 LohSUTs, and 5 LohSWEETs were upregulated in 'Sorbonne' 1 day after scale detachment treatment, suggesting that they may regulate the initiation of the bulblet. A total of 10 LflMSTs, 1 LflSUTs, and 6 LflSWEETs were upregulated 4~6 months after sowing, which corresponds to the juvenile-to-adult transition phase of Lilium × formolongi, suggesting that they may also play a role in the accompanying bulb swelling process. Combined with quantitative real-time PCR (qRT-PCR) analysis, LohSTP8 and LohSTP12 were significantly overexpressed during the extremely early stage of bulblet initiation, and LflERD6.3 was significantly overexpressed during the growth of the underground bulblet, suggesting that they may be key sugar transporters in the formation of lily bulbs, which needs further functional verification.