Fujian Coastal Area Research Articles

Risk Analysis and Visualization of Merchant and Fishing Vessel Collisions in Coastal Waters: A Case Study of Fujian Coastal Area

The invasion of ship domains stands out as a significant factor contributing to the risk of collisions during vessel navigation. However, there is a lack of research on the mechanisms underlying the collision risks specifically related to merchant and fishing vessels in coastal waters. This study proposes an assessment method for collision risks between merchant and fishing vessels in coastal waters and validates it through a comparative analysis through visualization. First of all, the operational status of fishing vessels is identified. Collaboratively working fishing vessels are treated as a unified entity, expanding their ship domain during operation to assess collision risks. Secondly, to quantify the collision risk between ships, a collision risk index (CRI) is proposed and visualized based on the severity of the collision risk. Finally, taking the high-risk area for merchant and fishing vessel collisions in the Minjiang River Estuary as an example, this paper conducts an analysis that involves classifying ship collision scenarios, extracts risk data under different collision scenarios, and visually analyzes areas prone to danger. The results indicate that this method effectively evaluates the severity of collision risk, and the identified high-risk areas resulting from the analysis are verified by the number of accidents that occurred in the most recent three years.

Modeling and Simulation of a Turbine Access System with Three-Axial Active Motion Compensation

As an essential transportation equipment for personnel to access offshore wind plants, the safety and stability of the turbine access system (TAS) have gained increasing significance. However, when sea conditions deteriorate, the end of the TAS will experience large-angle shaking and an increase in the heave height. A novel 3-DOFs TAS with active motion compensation for the Fujian coastal area is designed to solve the problem of the stability of the end of the TAS under sea conditions with a significant wave height of 2.2 m, including structural design, kinematic analysis, hydraulic drive design, and control system design. In the research, a new stacking compensation method is proposed to compensate for the roll angle, pitch angle, and heave height at the end of the TAS. The 3-DOFs TAS is modeled mathematically by the Denavit–Hartenberg parameters, and the hydraulic system model is established. In order to improve the compensation effect, a fuzzy PID controller with feedforward compensation is designed based on fuzzy PID control, and the model simulation experiment is carried out by MATLAB/Simulink. Finally, the experimental simulation shows that under the compensation of the feedforward compensation fuzzy PID control algorithm and the new compensation algorithm, the roll angle of the TAS is reduced by a maximum of 84.8%, the pitch angle is reduced by 75%, and the heave height is reduced by 73.6%. This validates the effectiveness of the proposed scheme and provides a reference for future TAS design and development.

Controlling effects of cap rocks on the formation of deep geothermal resources

Cap rocks with high thermal insulation are important for deep geothermal systems at a depth of 3000‒6000 m. Based on the deep geothermal geological conditions in the Fujian-Guangdong-Hainan area of South China, this study established an ideal geological model of reservoir-cap rock assemblages and simulated the geothermal field distribution of cap rocks of different thicknesses and thermal conductivity. The simulation results show that the vertical geothermal temperature distribution in an uplifted area of a depression was present as inverted mirror reflections relative to the elevated area of the basement. Specifically, the isotherms above the elevated area are convex in shape, while those below the elevated area are concave. There is a temperature equilibrium line between the convex and concave isotherms. The heat flow moves from the depressed area to the uplifted area below the temperature equilibrium line and migrates in an opposite direction above the line. On this base, this study conducted the inversion of geothermal temperature fields in typical areas with thin, moderately thick, and thick cap rocks. The results indicate that, at the depth of 3000–6000 m, areas with thin cap rocks (igneous rock zone in the coastal area of Fujian) mainly host moderate- to low-temperature hydrothermal resources; areas with moderately thick cap rocks (Yuezhong Depression) have the geothermal temperature ranging between 100 °C and 200 °C and may develop moderate- to high-temperature hydrothermal resources and hot dry rocks (HDRs), with the former superimposing on the latter; and areas with thick cap rocks (onshore Beibuwan Basin) have a geothermal temperature of 120‒220 °C, and contains mainly moderate- to high-temperature hydrothermal resources and HDRs. Therefore, it is recommended that the evaluation, exploitation, and utilization of deep geothermal resources be carried out according to the burial depth of the temperature equilibrium line and the specific demand for geothermal resources.

Chromaticity characteristics of soil profiles in the coastal areas of Fujian and Guangdong, southern China and their climatic significance

In recent years, there has been an increasing interest in the use of soil color as a climatic proxy. We investigated the variation of soil chromaticity parameters in subtropical and tropical coastal areas in China and their relationships with climatic factors (mean annual precipitation and temperature). Latitudinal zonal soil profiles in the coastal areas of Fujian and Guangdong were selected for study, and chromaticity analysis of soil samples was performed using the CIELAB color system. The principal results are as follows: (1) Soil color in the coastal areas of Fujian and Guangdong is mainly controlled by hematite and goethite. Redness (a∗) varies significantly with depth within the soil profiles, and two types of profile can be defined: type I in which a∗ decreases with increasing depth within the profile, and type II in which a∗ increases with increasing depth within the profile. (2) Overall, a∗, b∗ (yellowness) and the b∗/a∗ ratio do not show a significant relationship with latitude. The a∗ of some of the Fujian profiles and the Guangdong soil profiles are significantly negatively correlated with the MAP, the b∗/a∗ of some of the Fujian is highly positively correlated with MAP. A precipitation threshold may exist for both sets of profiles. There is a high correlation coefficient between b∗/a∗ and MAT, and a temperature threshold of ∼23 °C is evident. b∗/a∗ is correlated with MAP and MAT, and it can potentially be used as a climate proxy.

Zircon reveals crystal-melt segregation processes in the genesis of Cretaceous A-type granites and related cumulated rocks in southeastern China

A-type granites are a distinctive group of igneous rocks classified based on chemical and mineralogical criteria. Although numerous theories for the origin of A-type granite have previously been proposed, their genesis remains highly controversial. In the current study, we present bulk-rock geochemistry and zircon UPb isotopes, Hf isotopes, and trace elemental data for a suite of quartz monzonite, porphyritic granite, and miarolitic alkali feldspar granite from the coastal area of Fujian, southeastern China, to evaluate the genetic link between these rocks. Zircon UPb dating indicates that these rocks were crystallized at ∼94–102 Ma. Our data strongly suggests that lithological differences in these rocks are the result of crystal-melt segregation in the shallow crust. The quartz monzonites are enriched in Sr and Ba, with high Zr/Hf and low silica content and a weak negative Eu anomaly, representing the cumulate residue from the crystal-melt segregation of a magma reservoir. A limited fraction of zircon from the quartz monzonite has evolved trace element signatures (high Hf, Nb, Y, U; low Eu/Eu⁎), indicating that the quartz monzonite represents a mixture of accumulated crystals and high silicic melt trapped in cumulate mush. The miarolitic alkali feldspar granites and porphyritic granites are enriched in silica and Rb, and depleted in Sr and Eu. They also display low whole-rock Zr/Hf and Eu/Eu⁎ ratios, and high Rb/Sr ratios, representing highly evolved silicic melts that were segregated from a magma reservoir. The majority of the zircon grains from the miarolitic alkali feldspar granites exhibit the most evolved trace element signatures (high Hf, Nb, Y, U; low Zr/Hf and Eu/Eu⁎) of the entire suite. This reveals that these zircons crystallized from the high silicic melts extracted from a magma reservoir. Magma recharge and the exsolution of volatiles from the interstitial melt have promoted the segregation and upward extraction of high silica magmas from a compacting magma reservoir in the upper crust. Our work demonstrates that the miarolitic alkali feldspar granites with A-type granite features from the coastal area of southeastern China were generated by the crystal-melt segregation process in a shallow crustal magma reservoir.

OSL chronological evidence reveals one of the earliest island-type Neolithic sites in the coastal area of South China

Many prehistoric sites are preserved in the southeast China coastal area; however, it is still unclear when ancient human activity occurred owing to a lack of chronological evidence, which is unfavourable for research on the coupling of prehistoric man-earth relationships. In this study, we present an optically stimulated luminescence (OSL) chronology analysis of two profiles (T1 and T4) collected from the Neolithic Jianhu (JH) site on Haitan Island, South China. The single-aliquot regenerative-dose (SAR) protocol for coarse silt (38–63 μm) quartz was used to determine the equivalent dose (De). The results showed that the OSL technology is reliable and of great value for archaeochronology in coastal aeolian regions. The results suggest that the JH site is one of the earliest Neolithic sites in the coastal area of Fujian. The ages of cultural layers with ancient human activities at the JH site varied from 7.4 ± 1.13 to 5.77 ± 0.35 ka, thereby making the JH site the earliest Neolithic site in the coastal area of Fujian. The sand-tempered pottery unearthed from the JH site can be used as direct evidence of ancient human survival, and its age is 6.33 ± 0.21 ka with a high precision, which presents the earliest OSL data on pottery in South China. We also discuss the regional environmental background of ancient human activity. The Keqiutou culture corresponds to a period of relatively high sea level and a superior natural environment on Haitan Island. The sea retreat 5.7 ka ago was a crucial factor driving prehistoric human migration to the Fuzhou Basin and Taiwan Island.

Study on the effect of inflow conditions on wind flow acceleration in mountainous micro-topography

The acceleration of wind flow in mountainous areas can cause the destruction or collapse of transmission towers. The wind speed and direction of inflow have a significant impact on the flow acceleration in mountainous areas. The mountain terrain in the coastal area of Fujian was selected to study the influence of the inflow wind speed and direction on the acceleration effect. By analyzing the radar chart of the wind speed acceleration ratio of the monitoring points under 24 wind direction angles, the variation law of the wind speed acceleration ratio is consistent with the trend of the influence law obtained by the analysis of the surrounding terrain. The obtained simulation results are correct and credible, which can be used to correct the design wind speed of transmission lines in mountainous areas.

Chromaticity Characteristics of Soil Profiles in the Coastal Areas of Fujian and Guangdong and Their Climatic Significance

Chromaticity Characteristics of Soil Profiles in the Coastal Areas of Fujian and Guangdong and Their Climatic Significance

Semi-/Weakly-Supervised Semantic Segmentation Method and Its Application for Coastal Aquaculture Areas Based on Multi-Source Remote Sensing Images—Taking the Fujian Coastal Area (Mainly Sanduo) as an Example

Coastal aquaculture areas are some of the main areas to obtain marine fishery resources and are vulnerable to storm-tide disasters. Obtaining the information of coastal aquaculture areas quickly and accurately is important for the scientific management and planning of aquaculture resources. Recently, deep neural networks have been widely used in remote sensing to deal with many problems, such as scene classification and object detection, and there are many data sources with different spatial resolutions and different uses with the development of remote sensing technology. Thus, using deep learning networks to extract coastal aquaculture areas often encounters the following problems: (1) the difficulty in labeling; (2) the poor robustness of the model; (3) the spatial resolution of the image to be processed is inconsistent with that of the existing samples. In order to fix these problems, this paper proposes a novel semi-/weakly-supervised method, the semi-/weakly-supervised semantic segmentation network (Semi-SSN), and adopts 3 data sources: GaoFen-2 image, GaoFen-1(PMS)image, and GanFen-1(WFV)image with a 0.8 m, 2 m, and 16 m spatial resolution, respectively, and through experiments, we analyze the extraction effect of the model comprehensively. After comparing with other the-state-of-art methods and verifying on an open remote sensing dataset, we take the Fujian coastal area (mainly Sanduo) as the experimental area and employ our method to detect the effect of storm-tide disasters on coastal aquaculture areas, monitor the production, and make the distribution map of coastal aquaculture areas.

3-D isotropic and anisotropic shallow crustal structure on Pingtan Island, Fujian, southeastern coast of China

Pingtan Island is located on the southeastern coast of China between the Changle-Zhao'an and Binhai fault zones. We use P- and S-wave traveltime data from marine large-volume airgun sources for 3-D velocity structure inversion, and the spatial resolution is high at depths of 1–3 km. The isotropic inversion results show that the velocity in the island is higher in the midwestern area, which consists of sedimentary plains. The velocity is lower in the southern and eastern areas, which consist of eroded hills. Then we perform azimuthally anisotropic inversion using the obtained isotropic model as the initial model. The fast directions in the island are predominantly NE-SW and NNE-SSW, consistent with the main fault structures along the southeastern coast of China. The magnitude of anisotropy gradually decreases from south to north, consistent with the decreasing intensity of fault activity from south to north. On the southeastern coast of China, the fast direction in the upper crust is nearly orthogonal to that in the upper mantle from previous studies, which is nearly parallel to the absolute plate motion in the lower crust and upper mantle. The faults along the Fujian coastal area and Taiwan formed at different time period. But the fast directions in these two areas are similar. Therefore, the fast direction is mainly dominated by the trends of faults and fractures in the upper crust. And it is dominated by aligned olivine crystals induced by plate motion in the lower crust and upper mantle.

The M2 Cotidal Chart in the Bohai, Yellow, and East China Seas from Dynamically Constrained Interpolation

AbstractThe harmonic constants extracted from tidal gauge stations and satellite altimeter observations are usually sparsely distributed in the continental marginal seas, but they are precious data for addressing the main characteristics of different constituents. In this paper, a dynamically constrained interpolation methodology (DCIM) is developed and applied to interpolate the observed harmonic constants of the M2 constituent from satellite altimeter observations in the Bohai, Yellow, and East China Seas (BYECS) with those from tidal gauge stations for validation. In the DCIM, the tide model provides dynamical constraints to interpolate the observations, and the adjoint assimilation method provides iterative optimization for the interpolated results by adjusting key model parameters. In particular, a substantial quantity of enhanced “observations” generated from the interpolated results of the domain are further interpolated with the sparse observations in the subdomain. The final interpolated results for each subdomain, naturally blending the dynamical constraints from the dynamical model with statistical information from observations, can describe the main characteristics of the M2 constituent in the BYECS, the continental shelf sea of the East China Sea, and the Zhejiang–Fujian coastal area, respectively. The results indicate that the DCIM is feasible and effective to utilize the observations to obtain high-accuracy cotidal charts for regional ocean.

Development of a new cultural design process using Kansei engineering and fuzzy techniques

PurposeBelief in Mazu has a crucial cultural status in Taiwan and the coastal area of Fujian, China. The design and manufacture of apparel and accessories to be placed on statues of the deity are also considered a sacred and critical part of the religion’s cultural and artistic inheritance. The crown hat of Mazu is one of the most essential elements of the deity’s apparel. The paper aims to discuss these issues.Design/methodology/approachThis study explored the styles of Mazu crown hats using Kansei engineering (KE). People generally use adjectives words to provide aesthetic evaluations. Fuzzy theory is suitable for processing linguistic problems that include vagueness, thereby providing a reasonable method of quantifying such aesthetic evaluations. Therefore, this study first established a fuzzy positioning model (FPM) of word evaluations for analysis. Factor analysis was used to obtain representative image adjectives that represented Mazu’s image. Fuzzy analysis methods were then employed to rank the various image adjectives through evaluation words and to determine the differences between adjectives. Finally, on the basis of image analysis results and expert suggestions, the crown hat was redesigned and its suitability verified.FindingsFour results were obtained. First, four image adjectives appropriate for representing Mazu’s image were identified, of which “noble and kind” is the most suitable. Second, fuzzy analysis was found to successfully rank style images. Third, the crown hat style and design characteristics suitable for Mazu were acquired. Fourth, the verification demonstrated that the redesign effectively enhanced the perceived image of the crown hat design.Originality/valueThis study employed KE to improve the design of a Mazu crown hat. The proposed FPM can aid the development of cultural and creative design.

Optically stimulated luminescence dating of coastal sediments at Funing Bay, Southeastern China

Abstract The possible role of environmental change, especially sea level change, as a stimulus for the development of human residence and migration is poorly understood. We investigate this problem by showing a record of sea-level change and coastal transformation based on a sediment core (FN1 core) and a Neolithic site (Pingfengshan site) obtained from the Funing bay on the northeast coast of Fujian, China. The Funing bay coastal area represents a unique feature in China’s Neolithic cultures, comprising a silty beach dominated by quartz-rich sand and several important sites of Huangguashan cultural period. Samples from FN1 core and Pingfengshan site were taken for grain size ananlyses and for optically stimulated luminescence (OSL) dating. The blue-light stimulated OSL signals were measured by the single aliquot regenerative dose (SAR) protocol to determine the ages of of the samples. Samples from FN1 core yield OSL ages ranging from 49.9 ka to 0.8 ka, providing the systematic geochronological evidence for the sea level change of Funing bay. The comparison of sea level change and Neolithic cultural periods presents a good relationship in coastal area of Fujian, China since about 7 ka before present. In detail, the cultural types of Keqiutou culture and Huangguashan culture all belong to coastal mountainous culture, of which flourishing periods corresponds to the higher sea level periods of mid-late Holocene. Tanshishan culture belongs to estuarine coastal culture, and most sites of this period correspond to a lower sea level located at lower altitudes.

Investigating the late neolithic millet agriculture in Southeast China: New multidisciplinary evidences

The spread of millet agriculture to southeast (SE) China is critical to understanding the region's economic pattern and its potential impact on the proposed initial expansion of proto-Austronesians. In this study, we present new multidisciplinary evidence for the development of millet agriculture from three Neolithic sites in Fujian Province, China: Hulushan, Pingfengshan and Huangguashan. The carbonized seeds from Hulushan indicate the existence of millet agriculture around 3842-3649 cal. BP. Meanwhile, we tested stable carbon and nitrogen isotope ratios of faunal remains (n = 22) from Pingfengshan and Huangguashan shell midden sites in a coastal area of Fujian. The stable isotope results for pigs (δ15N values range from 4.9 to 11.2‰, and δ13C values range from −24.1 to −11.2‰) show significant variations, suggesting that these pigs were fed different foods, including C3 plants, C4 plants and marine resources. Specifically, two samples of pig collagen with strong millet signals were directly dated to about 4000-3600 cal. BP. These new findings provide substantial evidence for a new understanding of the development of millet agriculture in SE China.

A13521 Association of microalbuminuria and retinal vessel in population with essential hypertension in Fujian coastal area

A13521 Association of microalbuminuria and retinal vessel in population with essential hypertension in Fujian coastal area

A13320 Associations between gene polymorphisms of the apelin-APJ system and hypertensive vascular damage

Objectives: The aim of this study was to investigate the association of apelin-APJ patyway single nucleotide and hypertensive vascular damage through brachial ankle pulse wave velocity (baPWV). Methods: A total of 556 hypertensive subjects, including 173 males and 383 females (aged 58 ± 11.0 years) were enrolled in this study based on a cross-sectional survey in Fujian coastal area. All subjects were given physical examination, laboratory test and baPWV measured. Genotypes of the apelin (rs56204867, rs3761581 and rs3115757) and APJ (rs9943582 and rs7119375) genes were determined by the TaqMan® MGB probe method. Results: Participants were divided into two groups on the basis of baPWV values: control group (baPWV < 1400 cm/s) and arterial stiffness group (baPWV≥1400 cm/s). The average baPWV value was (1266 ± 111)cm/s in the control group and (1764 ± 296) cm/s in the arterial stiffness group. The frequencies of mutant alleles in all five SNPs were not significantly different between the arterial stiffness and control groups (all P > 0.05). After adjusting for age, partial correlation analysis showed that male subjects carrying the apelin rs3115757-C mutant allele had a significantly higher baPWV value than those with the wild-type G allele [(1536 ± 375)cm/s vs (1383 ± 304)cm/s, P = 0.01] (Table 1). Logistic regression data demonstrated that female subjects with the apelin rs56204867-C mutant allele had an increased risk of developing arterial stiffness (OR = 2.087, 95%CI:1.018¡«4.276, P = 0.04). Conclusion: The apelin SNP rs56204867 was associated with reduced arterial elasticity in female hypertensive subjects, which indicates that gene polymorphisms of the apelin-APJ system are correlated with hypertensive vascular damage.

Species distribution characteristics of arsenic in shellfish seafood collected from Fujian Province of China

Various shellfish samples were collected from seven coastal areas of Fujian, China, and their arsenic species characteristics were investigated. The results showed that there are six different arsenic species, i.e. arsenite, arsenate, dimethylarsinic acid, arsenobetaine, 5-deoxy-5-dimethylarsinoyl-β-ribofuranose and one unknown arsenic compound As1, existing in shellfish. Among 40 samples, arsenite was detected in 18 shellfish samples at the concentration range of 5–41 ng/g wet weight, and the later five arsenic species were detected in all shellfish samples at the concentration range of 0.01–0.07, 0.01–0.12, 0.13–1.52, 0.03–0.48 and 0.01–0.23 μg/g wet weight, respectively. The experimental results also revealed that the arsenic species characteristics in shellfish were dependent on both the shellfish species and sampling sites. For all 40 shellfish samples, arsenobetaine was the predominant species, its concentration accounted for 25–86% of total concentration of arsenic species; 5-deoxy-5-dimethylarsinoyl-β-ribofuranose was the subdominant arsenic species, its concentration accounted for 4–46% of total concentration of arsenic species. Our results provided basis for scientifically evaluating the arsenic uptake risk of shellfish samples.

Using self-organizing map for coastal water quality classification: Towards a better understanding of patterns and processes

Self-organizing map (SOM) was used to explore the spatial characteristics of water quality in the middle and southern Fujian coastal area. Nineteen water quality variables (temperature, salinity, pH, dissolved oxygen, alkalinity, chemical oxygen demand, nutrients NH4-N, H2SiO3, PO4−, NO2−, and NO3−, heavy metals/metalloid Cu, Zn, As, Cd, Pb, Hg, and Cr6+, and oil) were measured in the surface, middle, and bottom water layers at 94 different sampling sites. Patterns of water quality variables were visualized by the SOM planes, and similar patterns were observed for those variables that correlated with each other, indicating a common source. pH, COD, As, Hg, Pb, and Cr6+ likely originated from industries, while nutrients NH4-N, NO2−, NO3−, and PO43− were mainly attributed to agriculture and aquaculture. The k-means clustering in the SOM grouped the water quality data into nine clusters, which revealed three representative water types, ranging from low salinity to high salinity with different levels of heavy metal/metalloid pollution and nutrient pollution. Spatial changes in water quality reflected the impacts of natural factors (riverine outflows, tides, and alongshore currents), as well as anthropogenic activities (mariculture, industrial and urban discharges, and agricultural effluents). Principal component analysis (PCA) confirmed the clustering results obtained by SOM, while the latter provides a more detailed classification and additional information about the dominant variables governing the classification processes. The results of this study suggest that SOM is an effective tool for a better understanding of patterns and processes driving water quality.

软岩嵌岩桩承载力的计算与试验对比分析

在福建沿海地区许多重要建筑物都是以软岩作为其桩基持力层，本文依托某高层建筑的工程情况，对该工程中具有代表性的6根软岩嵌岩桩，按照JGJ94-2008《建筑桩基技术规范》、GB5007-2011《建筑地基基础设计规范》来计算其单桩竖向承载力，并进行了现场荷载试验，对计算和试验结果进行对比分析，得出了有意义的结论，为同类工程提供参考。 Many important buildings in coastal areas of Fujian are soft rock as its pile foundation bearing layer. Based on engineering geological conditions of a tall building, for six typical rock-socketed piles in soft rock area, according to Technical Code for Building Pile Foundation (JGJ94-2008) and Design Code for Building Foundation (GB5007-2011), this paper calculates vertical bearing capacity of single pile, and the load tests are carried out. The calculation and test results are compared and analyzed, and some useful conclusions are drawn. These conclusions will provide references for similar projects.

Species characteristics of lead in sea foods collected from coastal water of Fujian, Southeastern of China.

Various sea foods including fish, shellfish and shrimp were collected from different coastal areas of Fujian in China, and their Pb species characteristics were investigated in detail. The results indicated that there are two different species characteristics of Pb existing in sea food samples. About half of samples were detected to have only Pb2+, and another half of samples were detected to have both Pb2+ and trimethyl lead (TML). The results also revealed that Pb species characteristics in the sea foods rather depend on the species of sea food than the sampling area. In comparison with shellfish/shrimp samples, fish samples have higher concentrations of TML and Pb2+. Especially, the average concentration of TML in the TML-detected fish samples is about 3 times of that in the TML-detected shellfish/shrimp samples, indicating that fish has stronger ability to uptake and accumulate TML. The concentrations of total lead in all samples are lower than the maximum allowable limit of national standard, suggesting that the sea foods collected from Fujian are safe for consumption. By considering that TAL has more toxicity than Pb2+, the effect of TML in sea foods on the human health should be paid more attention in the future.