Flat Width Research Articles

2DH Numerical Study of Solitary Wave Processes around an Idealized Reef-Fringed Island

In order to better understand the role of coral reefs around an isolated island in mitigating tsunami hazards, this study performed a horizontally two-dimensional (2DH) numerical study of tsunami-like solitary wave propagation and run-up around an idealized reef-fringed island. The shock-capturing Boussinesq wave model, the FUNWAVE-TVD is used in the present study and well-validated with existing experimental data for its robustness in predicting 2DH solitary wave processes around an island. Based on the validated model, the typical solitary propagation process around the reef-fringed island and the effects of morphological and hydrodynamic parameters on the maximum run-up heights were systematically investigated. It is found that coral reefs can effectively reduce maximum run-up heights around an isolated island. The reef flat’s water depth, reef flat width, and reef surface roughness are the main factors affecting maximum run-up heights around an island, while the fore-reef slope has little impact. For the idealized reef-fringed island in this study, sea-level rise will cause coral reefs to lose their protective capability on the lee side, and the presence of coral reefs may even enhance tsunami hazards around an island when the reef flat width is very narrow or coral bleaching happens.

Co-creating a coastal climate service to prioritise investments in erosion prevention and sea-level rise adaptation in the Maldives

While the prioritisation of scarce resources for climate adaptation is becoming a priority for low and middle income countries, the climate service literature addressing adaptation prioritisation decisions is scarce. This paper contributes to filling this gap by presenting a co-creation process carried out in the Maldives among representatives of government, civil society and researchers. Together, we identified the need to improve a ranking method currently used by the Maldivian government to prioritise islands for investments in erosion prevention. As a solution we developed a layered index. The first layer of this index captures the objective dimension of the problem through an erosion hazard subindex, using the three variables wave energy, reef health and reef flat minimum width. The second layer captures the normative dimension through a multi-criteria analysis using the erosion hazard subindex as one criterion next to other stakeholder selected criteria such as critical infrastructure, economic activity, per capita income and the potential to house additional people that resettle from riskier places as sea-level rise progresses. Results of this new ranking method show that socioeconomic criteria were considered more important by the stakeholders than the biophysical criterion of erosion hazard. Among the top-ranked islands are many regional centres but also less populous islands that have a large potential to house additional people. Lessons learnt from the co-creation process highlight the importance of assembling interdisciplinarity teams, fostering mutual learning among project participants, and designing research projects that do not prescribe upfront the exact problems to be addressed and methods to be applied.

Finding patterns of atoll morphometrics at a range of spatial scales

Small Island Nations, often comprised of Atolls, are at considerable risk of climate change impacts from sea-level rise to coral acidification to increasing cyclone intensity; understanding how they will change in the coming century is vital for climate mitigation and resiliency. However, the morphology of atolls are not well quantified or summarized. In this work, we calculate modern atoll morphometrics on a global scale including 3,786 motu and 593 reef flats on 154 atolls. Temporal composites of Landsat imagery are created for 4 years (2015–2018), and are classified into motu, reef flat, open water/lagoon via unsupervised classification. Morphometrics, including widths, lengths, and area, are computed for each motu and reef flat of the atoll in Python, creating a database of atolls and their associated morphometrics. Consistency in automated processing of atoll morphometrics removes spatial and user bias, enabling a better understanding of geographic patterns of atoll area and other morphometrics. Distinct differences in the distribution of motu are seen on a regional scale in French Polynesia, while globally, wider reef flats and larger motu are found closest to the equator. Globally, there is a consistent reef flat width in front of large motu (>1 km length) of 184 ± 93 m (n = 724). Our atoll morphometric database creates a baseline of current atoll characteristics that can be expanded upon in the future and used for evaluating temporal changes to atoll islands.

Ultraviolet-C AlGaN Resonant-Cavity Light-Emitting Diodes with Thermal Stability Pipe-AlGaN-Distributed Bragg Reflectors.

Ultraviolet-C AlGaN resonant-cavity light-emitting diodes with top and bottom pipe-AlGaN-distributed Bragg reflectors (DBRs) have been demonstrated. For the top/bottom DBR structures, 20 pairs of n+-AlGaN:Si/n-AlGaN:Si stack structures were transformed into the pipe-AlGaN:Si/n-AlGaN:Si DBRs through a doping-selective electrochemical wet etching process. The reflectivity of the pipe-AlGaN DBR structure was measured as 90% at 276.7 nm with a 20.9 nm flat stopband width. The anisotropic optical properties of the pipe-AlGaN DBR structure had been analyzed through the polarization-dependent reflectance spectra. For temperature-dependent reflectance spectra, the central wavelengths were slightly redshifted from 275 nm (100 K) to 281 nm (600 K) due to thermal expansion, refractive index increase, and partial strain release phenomena in the pipe-DBR structure. High photoluminescence emission intensity and line-width reducing phenomena were observed at 10 K in the UVC-LED with the resonant-cavity structure, which has potential for high-efficiency UV-C light source applications.

Design and optimization of dry powder jet cleaning nozzles for airport navigation lights

The research of this work is based on the nozzle design and optimization of dry powder (NaHCO3) jet cleaning system for airport navigation aid lamps. In this cleaning system, compressed air drives dry powder (NaHCO3) abrasive, and a gas-solid mixed high-speed jet is sprayed onto the surface of the luminaire through the nozzle to scour and clean the dirt attached to the surface of the luminaire. Based on the computational fluid dynamics and flow field theory, three types of nozzle structures, namely tapered nozzle, Laval nozzle, and flat nozzle, were studied; the DPM (Deformable part model) model in Fluent was used to analyze the internal and external flow fields of the nozzle mixed with the gas-solid two-phase flow to obtain the velocity field, pressure field and nozzle wear rate of the mixed gas, and the flat nozzle was selected and the nozzle parameters were optimized. The optimized level combination of flat type nozzle structure is obtained with a flat width of 4mm, flat height of 24.5mm, and flat length of 55mm.

Loss of tidal creek ecosystem vitality caused by tidal flat narrowing on the central Jiangsu coast, China

Globally, tidal flats are increasingly narrowing due to continuous reclamation and sea level rise. Nonetheless, the impact of tidal flat narrowing (TFN) on tidal creek systems that play a crucial role in the formation and shaping of tidal flats is not well understood, despite a cognition that the tidal flat-creek system is integrated and coevolved. In this study, based on the quantification and mapping of tidal creek ecosystem vitality (TCEV), we detected the state evolution of tidal creek systems in response to TFN process on the central Jiangsu coast (CJC), China. The results showed that two thirds of the original tidal flat width was lost from 1984 to 2020, with a narrowing rate of 210.9 m/yr. The seaward movement of seawall lines and the landward movement of low tide lines contributed 82.5 % and 17.5 % to this serious TFN process, respectively. Across the study period, the overall TCEV lost 82.3 % with a substantial transformation from high level to low level. In terms of three dimensions of structural complexity, functional integrity and spatial occupancy, the tidal creek system of CJC has greatly deviated from the high-quality state in 1984, which was significantly associated with TFN. For a natural mature tidal flat, the loss of its initial width seems acceptable when <1/3, but unacceptable when >1/2, which are two important thresholds corresponding to the lower and higher loss of TCEV, respectively. It is worried that the CJC tidal flat-creek system would fall into a vicious circle of state evolution. Therefore, efforts should be made to control irrational reclamation and perform ecological restoration based on an insight into the relationship between TCEV and TFN.

Hydrodynamics and sediment transport patterns on intertidal flats along middle Jiangsu coast

Two field campaigns in Dafeng and Jianggang were organized to compare spatial variations of hydrodynamic characteristics and sediment transport patterns on intertidal flats of different types with distinct human interferences along middle Jiangsu coast, China. The major contributors to the different patterns of sediment dynamics between the two tidal flats were offshore tidal current field and human interference. Offshore tidal force provide the basic setup of tidal current patterns on tidal flats, which is then modified by local morphology. Seawalls parallel to coast reduce tidal flat width, forcing tidal energy to dissipate within a shorter distance and thus influencing tidal flat morphology. Seawalls vertical to coast and major tidal current significantly reduce tidal current speed, which favors sediment deposition on tidal flats. Two seawalls built on both sides of the observational tidal flat profile caused much reduced current speed at Dafeng tidal flat, comparing to the offshore station. Being exposed to offshore radial tidal currents, hydrodynamics at Jianggang was much stronger than that at Dafeng. Residual currents at both areas showed net landward transport at the lower flat and net seaward transport at the upper flat, in favor to sediment accumulation at the middle flat. Sediment flux over tidal cycles showed net landward sediment transport at Dafeng, and net seaward transport at Jianggang, consistent with the convex-up accretion-dominated profile observed at Dafenge, and concave-up erosion-dominated profile observed at Jianggang. The instantaneons sediment flux changed significantly due to variations in velocity and sediment concentrations, but these terms counteracted with each other within tidal cycles, leading to the dominant role of Eulerian flux in determining net sediment flux over tidal cycles.

Critical heat flux and bubble behaviour study on differently oriented flat plates during pool boiling

An experimental study is brought off to analyse the effect of flat plate length, width, orientation, and pool liquid temperature on CHF under atmospheric conditions during pool boiling. The bubble nucleation and departure for the aforementioned parametric and operational conditions are discussed. Based on bubble behavior, various pool boiling regimes under uniform heat flux conditions are investigated. The pool is maintained at 25℃ and saturation temperature corresponding to ambient pressure. The occurrence of burnout on the heater plates is analysed on the basis of bubble behaviour. It is analysed that prior to the occurrence of CHF a liquid film enclosed with vapour leads to initiate the dry patch. It is observed that with an increase in pool temperature, the magnitude of CHF reduces. It has been estimated that there is a decrement of around 62 % in the magnitude of CHF in saturated conditions as compared with subcooled conditions. The vertical orientation of the plates results in a higher CHF magnitude. In the subcooled pool, the CHF in vertical orientation ranges between 6.197 MW/m2 to 2.909 MW/m2. Whereas in the saturated pool the CHF magnitude in vertical orientation ranges between 2.652 MW/m2 to 0.998 MW/m2. As the length of the heater plate increases, the CHF value reduces. The minimum magnitude of CHF is obtained as 0.898 MW/m2 for downward facing heater of 300 mm in length at the saturated pool. Higher the width lesser the CHF. The obtained experimental results are compared with available correlations to access its viability. An empirical correlation is suggested, implicating the effect of heater length, width, orientation, and pool temperature for the pool boiling CHF on flat plates.

Is condyle morphology a factor for anterior temporomandibular disc displacement?

To investigate morphological features of the mandibular condyle and its association with anterior temporomandibular disc displacement on sagittal oblique MRI plane. One hundred and twenty patients with temporomandibular MRI examination were retrospectively involved in the study. Patients aged less than 18 years and those with severe osteoarthritis, posterior disk displacement, tumor, abscess, history of a rheumatic disease, facial trauma, and motion artifacts on images were excluded. Three radiologists evaluated all images in consensus. Temporomandibular disc locations were classified as normal, anteriorly displaced with reduction (ADr), and anteriorly displaced without reduction (ADwr) on sagittal oblique T1-weighted images. Condylar shapes were classified as flat, rounded, and angled, and condyle anteroposterior width (c-APW) was measured on these images in closed-mouth position. Ninety six discs were in normal position (40%), 70 discs were ADr (29%), and 74 discs were ADwr (31%). Eighty-four condyles were flat (35%), 100 condyles were rounded (42%), and 56 condyles were angled (23%). Mean c-APW was 7 mm in normal joints, 5.9 mm in ADr, and 5.8 mm in ADwr joints, and it was smaller in joints with anterior disc displacement (p < 0.001). In normal joints, flat and rounded type condylar shape was more common and almost equally prevalent (44% and 43%); however, rounded type was more common among ADr (%47) and angled type was more common among ADwr joints (36%) (p = 0.008). Patients with anterior disc displacement were significantly younger from normal cases and anterior disc displacement was more common among female sex. Mandibular condyle shape alterations and condyle size on sagittal oblique MRI plane are associated with anterior disc displacement. Angled shape was more common among ADwr joints. Joints with anterior disc displacement had smaller c-APW than normal joints.

Optimization of 3D Printing Parameters of Biodegradable Polylactic Acid/Hydroxyapatite Composite Bone Plates.

The building parameters of three-dimensional (3D) printed polylactic acid/hydroxyapatite (HA) composite bone plates were optimized by an orthogonal experiment, and the effects of the layer thickness, printing speed, filament feeding speed, and HA content on the bending strengths of the specimens were analyzed. The deformation characteristics of the specimens were studied by 3D full-field strain analysis, and the internal defects of the specimens were analyzed. The effects of different combinations of the process parameters on the cross-sectional shape of the single deposited line, printing temperature, and pressure of the molten material were further analyzed. The results showed that the factors affecting the bending properties were the layer thickness, printing speed, filament feeding speed, and HA content, successively. The optimized process parameters were an HA content of 10%, a layer thickness of 0.1 mm, a printing speed of 30 mm/s, and a filament feeding speed of 0.8 mm/s, and the optimized specimen bending strength was 103.1 ± 5.24 MPa. The deposited line with a flat section shape and width greater than the print spacing helped to reduce the porosity of the specimens. The process parameters that resulted in large high-temperature areas and a high extrusion pressure could better promote material fusion.

Assessment of coastal erosion vulnerability and socio-economic impact along the Yangtze River Delta

Vulnerability assessment is critical for management of hazards in coastal area. However, research on erosion vulnerability assessment in delta region is still very limited. In this paper, we assessed the erosion vulnerability of 49 towns along the coast of the Yangtze River Delta by combining five physical (i.e., mean tidal range, mean wave height, suspended sediment concentration, tidal flat width, and coastal slope) and three social (i.e., embankment height, GDP per unit area, and fiscal revenue) indicators using the percentile ranking method. Population density and land use were analyzed to reveal the potential socio-economic impact of erosion. The assessment result of physical vulnerability is validated by comparison with the bathymetric change between 1980s and 2010s and previous assessment studies using different indicators and aggregation methods. Our results show that areas categorized as very high, high, moderate, low, and very low vulnerability account for 13%, 22%, 39%, 24% and 2% of the coastal towns, respectively. Vulnerable towns with very high and high socio-economic impacts are located along the coastline with narrow tidal flat and lower social coping capacities. The large variability in the physical vulnerability assessment result demonstrates that fine scale study at town level is extreme important, considering the spatial heterogeneity in geomorphological process within the fluival-tidal delta. Our method of erosion vulnerability assessment has potential use in deltaic environments elsewhere.

Variation Tendency of Coastline under Natural and Anthropogenic Disturbance around the Abandoned Yellow River Delta in 1984–2019

The coast around the Abandoned Yellow River Delta underwent significant changes under anthropogenic disturbance. This study aims to reveal the variation of the coastline, tidal flat area, and intertidal zone slope before, during, and after extensive reclamation during the period of 1984–2019 using satellite remote sensing images. In order to eliminate the influence of the varying water level, a new coastline correction algorithm had been proposed under the condition of insufficient accurate slope and water level data. The influence of seawalls on slope estimation were considered in it. The spatiotemporal evolution of coast had been analyzed and confirmed to be reasonable by comparing with the observed data. The results show that the coast can be roughly divided into a north erosion part and a south deposition part. Affected by reclamation, their tidal flat area in 2019 is reduced to only 43 and 27% of original area in 1984, respectively, which results in a continuous decrease in the tidal flat width. The adjustment of the tidal flat profile makes the slopes steeper in the erosion part, while the slopes in the deposition part remain stable. The reclamation has stimulated a cumulative effect as the disappearance of the intertidal zone, which may lead to the destruction of biological habitats.

Design of perforated cold-formed steel hollow stub columns using direct strength method

This paper presents a numerical investigation on the performance and design of cold-formed steel square (SHSs) and rectangular hollow sections (RHSs) stub columns having two opposite central circular perforations located at column mid-height. Finite element (FE) models are initially developed and validated against the experimental results on perforated YSt-310 cold-formed steel stub columns reported by the authors. A total of 264 experimental and numerical column capacities, collected from previous experimental investigations and current parametric study, has been utilized to compare with the design strengths predicted by available codified and proposed design equations. Based on the analysis, most of the presently available design equations for perforated stub columns provide overly-conservative and highly scattered design predictions. In particular, the Direct Strength Method in American Standard provides the maximum overly conservative prediction of about 60% with high scatterings. Hence, a modified DSM design equation has been proposed for various perforation size ratios (i.e. diameter of perforation to flat element width) considering the previous test results and current FE column capacities through least square regression analysis. The newly proposed design equation is shown to offer improved mean (conservative) and reliable predictions, and therefore recommended for inclusion in future revisions of design codes for perforated cold-formed steel tubular stub columns.

Study on the Shape Optimization of Composite Slope at the End of Irregular Boundary Open-Pit Mine

In order to optimize the shape of the compound slope at the end of the open-pit mine under the condition of non-irregular boundary, the compound slope composed of the stope end and the inner dump in the south of the open-pit mine in Pingshuo is studied. Due to the impact of land acquisition, the space of external dump is seriously insufficient, and with the development and change of mining engineering and the influence of geological structure, the problem of compound form optimization and the release and utilization of internal drain space in the south side is generated. Through field investigation and theoretical analysis and numerical analysis method, on the basis of investigating the ore party production status, to establish a 3 d geological model, select two battery profile typical position, using rigid body limit equilibrium method from the perspective of 2 d, in the full study south help shrink battery limit compound stope side slope and mine safety distance, flat width, and the direction of dump active line and the relationship between the stability design of multiple slope configuration scheme, through the various methods of slope stability, enforceability and comparing some important parameters such as displacement capacity, ultimately determine the technology feasible economic and reasonable boundary zone composite slope space form. Based on the above research results, FLAC3D software was used to study the stress-strain relationship inside the slope, revealing the deformation and failure mechanism and stability of the composite slope in the south bound area. The results show that the landslide mode and stability of the composite slope in the south bound area of pingshuoAndaobao open-pit coal mine are mainly controlled by the safe distance between stope and dump and the weak layer of 11 coal floor. According to the design, the economic and reasonable parameters of the composite slope in the south slope shrinkage boundary area are as follows: the safe distance between the stope end side and the dump site is 50m, the width of the dump flat plate is 60m, and the working line Angle of the dump line with the abandonment height of 255m is 125°, the total discard space was95,934,100 m3.

Tidal flat evolution law and its mechanism on the south bank of Hangzhou Bay from 1959 to 2019

The tidal flat evolution law is an important basis for protecting and developing tidal flat resources. The complex flow-sediment conditions and high intensity of human activities in Hangzhou Bay have led to complex tidal flat evolution mechanisms. The tidal flat evolution law and its mechanism on the south bank of Hangzhou Bay under the influence of flow-sediment variation and human activities in the past 60 years were analyzed based on the hydrographic and bathymetrical monitoring data of Hangzhou Bay in the period of 1959-2019, combined with the process of deposit-promoting and reclamation. The results show that the tidal flat on the south bank of Hangzhou Bay has been deposited since 1959, with a deposition rate of approximately 6.70 cm/a during 1959-2003, and increased to 12.59 cm/a during 2003-2019. Large-scale reclamation projects and the increased tidal range are the main reasons for the increase in the slope gradient of the tidal flat profile. The periodic evolution of the plane morphology of the Andong tidal flat is related to the cycle of high and low runoff, showing the increased/decreased curvature in wet/dry years. The reduction of incoming sediment from the Yangtze River has not significantly affected the deposition of the tidal flat on the south bank of Hangzhou Bay. The reclamation project is the main reason for the increased deposition rate and decreased tidal flat width of the south bank of Hangzhou Bay.

Bonding widths of Deposited Polymer Strands in Additive Manufacturing.

In this study, we explore the deformation of a polymer extrudate upon the deposition on a build platform, to determine the bonding widths between stacked strands in fused-filament fabrication. The considered polymer melt has an extremely high viscosity, which dominates in its deformation. Mainly considering the viscous effect, we derive analytical expressions of the flat width, compressed depth, bonding width and cross-sectional profile of the filament in four special cases, which have different combinations of extrusion speed, print speed and nozzle height. We further validate the derived relations, using our experimental results on acrylonitrile butadiene styrene (ABS), as well as existing experimental and numerical results on ABS and polylactic acid (PLA). Compared with existing theoretical and numerical results, our derived analytic relations are simple, which need less calculations. They can be used to quickly predict the geometries of the deposited strands, including the bonding widths.

Design and test of the crank slider mechanism feeding type rubber rotary cutting machine

Aiming at the problems such as low processing efficiency and high labor intensity when the rubber block was processed, a new type of crank slider mechanism feeding style rubber rotary cutting machine was designed with the help of computer. Starting with the two major processing steps of pushing and cutting the rubber block, an offset crank slider mechanism was used to push the rubber block in order to improve the processing efficiency of the rubber block. The V-belt was driven by the motor to rotate the circular saw blade, and the ball screw drove the rubber cutting table to make the rubber block perform reciprocating linear motion. The synthesis of the above two motions could achieve efficient cutting of the rubber block. Taking the needs of the rubber block cutting process into account, the flat belt width of the transmission rubber block was designed to be 355 mm, so that the machine had a good adaptability to rubber blocks. The modal simulation analysis determined that the optimal thickness of the circular saw blade was 3 mm and the optimal diameter of the circular saw blade was 500 mm. And the static finite element simulation analysis results also showed that the circular saw blade with this set of parameters had good strength and stiffness. After the orthogonal test was conducted on the prototype of crank slider mechanism feeding style rubber rotary cutting machine, the test results showed that the machine could cut 15 rubber blocks averagely per minute and each test produced less than 10 g rubber residue. In a word, the designed machine not only improved the cutting efficiency, but also met the demand for green and efficient processing of the modern agricultural products.

A Theoretical Framework for Characterizing Downlink Performance of Millimeter-Wave Networks for Highway Vehicular Communication

Associated and self-determining vehicles will play a significant job in upcoming Smart Transportation. what're more, brilliant urban areas, as a rule. High_speed and low_latency remote correspondence connections will enable regions to caution vehicles against security risks, and additionally, bolster cloud_driving arrangements to radically diminish roads turned parking_lots and air trash. To accomplish these objectives, vehicles should be outfitted by an extensive scope of devices creating and switching extreme rate information flows. As of late, millimetre wave (mm-Wave) methods have been offered as a method for satisfying such necessities. In_this_paper, we show a_highway network besides describing its key connection spending measurements. Specifically, we particularly think about a system in which vehicles_are assisted by mm-Wave Base_Stations installed beside the road. To evaluate our road_way, arrange, we build up another hypothetical model that represents a run of the mill situation where overwhelming vehicles, (for example, transports and lorries) in moderate paths impede Line_of-Sight_(LOS) ways of vehicles which are in fast tracks and, thus, perform as jams. Utilizing instruments from stochastic_geometry, we estimate for the_Signal-to-Interference-plus_Noise Ratio_(SINR) outage_probability, and in addition, the likelihood which a user accomplishes an objective correspondence (rate_coverage probability). Our examination gives new structure bits of knowledge to mm-Wave highway communication networks. In thought about highway situations, we demonstrate that lessening the flat beam width from 90 degrees to 30 degrees decides a negligible decrease in the SINR outage probability. Additionally, not at all like bi-dimensional mm-Wave cell systems, for little BS densities. it is as yet conceivable to accomplish an SINR outage_probability littler.

Morphological Characteristics of Tidal Creeks in the Central Coastal Region of Jiangsu, China, Using LiDAR

Tidal creeks are an important component of the intertidal zone and are essential for maintaining the balance between sedimentary processes and the hydrodynamic environment. A quantitative analysis of the morphological characteristics of tidal creeks is essential for understanding their processes of evolution and to evaluate the stability of tidal flats. This study describes the morphological characteristics of tidal creeks using a high-resolution airborne LiDAR DEM. The parameters include the number, order, length, width, depth, and width/depth ratio. The results show that the number and degree of development tidal creeks along the central coast of Jiangsu are higher than those in the radial sandbanks, and the mean width and length increase with the increasing tidal creek order. The number, length, and depth of tidal creeks in the salt marsh zone with well-developed vegetation are higher than those areas with little vegetation cover. The number of tidal creeks in the mid-upper intertidal zone is the largest, while the length and width of tidal creeks in the lower intertidal zone are the greatest. The differences in these characteristics are mainly related to the vegetation distribution, tidal flat width, and hydrodynamic conditions. Our findings potentially provide guidelines for coastal management and the evaluation of tidal flat stability.

Meiofauna and nematode community assemblage as sediment disturbance indicator in Mida Creek, Kenya

Abstract. Wafula M, Muthumbi A, Wang’ondu V. 2019. Meiofauna and nematode community assemblage as sediment disturbance indicator in Mida Creek, Kenya. Ocean Life 3: 24-37. Meiofauna is a group of benthic fauna mostly found in the sediments’ upper centimeters (cm), including Copepoda, Polychaeta, and Nematoda. This study focused on determining nematodes’ potential as bio-indicators of sediment disturbance caused by bait harvesting. Furthermore, bait harvesting was common, albeit with different intensities, on the different beaches of Mida Creek, Kenya, on November 2013. Sediment samples were collected along two transects within the mud flat running from the mangrove forest edge to the edge of the subtidal zone. Along the transects, 1 m² was placed at 20 m intervals. A replicate of 2 sediments core (3.4 cm diameter, 10 cm deep) was taken from each quadrat. Next, samples were fixed using 5% formalin, stored in plastic bottles, and then transported to the laboratory for processing and identification. The nematodes were used because it could bring out a clear difference in their distribution, community assemblage, diversity, and abundance due to sediment disturbance compared to other meiofauna. Of the total meiofauna, 3,988 individual nematodes were identified to the genus level. In addition, Nematoda was the most abundant taxon of all other meiofauna taxa. The bait harvesting through digging was more pronounced in Mayonda due to its wider mud flat width. The result showed a clear difference in the distribution, diversity, and community assemblage of the nematodes seen in all the sites. A sum of 83 nematode genera was encountered in Mida Creek. Kirepwe had 58 genera, Dabaso had 46 and Mayonda had 35. Mayonda had the highest nematode diversity, then followed by Kirepwe and Dabaso. On the contrary, Dabaso had the highest nematode density, then followed by Mayonda and Kirepwe. The meiofauna had a high community similarity, while nematode community similarity was lower at different levels of sediment disturbances. That makes the nematodes better bio-indicators as compared to meiofauna as a group. Therefore, this study points out that digging out polychaetes causes sediment disturbance. The disturbance affects the benthic fauna distribution, community assemblage, diversity, and abundance. Moreover, Terschellingia and Spirinia were distributed across all sites, even though in disturbed quadrats the numbers reduced significantly. On the contrary in disturbed quadrats, Viscosia, Pontonema, Synochium, Haliplectus, and Pheronus increased in numbers. To measures such as educating the fishermen on the effects of digging polychaete should be emphasized to safeguard marine biodiversity and its ecosystem.