East China Research Articles

Cooling History of Mesozoic Magmatism and Implications for Large-Scale Gold Mineralization in the Jiaodong Peninsula, East China: Constraints from T-t Paths Determined by U-Pb Thermochronology of Zircon and Apatite

Cooling History of Mesozoic Magmatism and Implications for Large-Scale Gold Mineralization in the Jiaodong Peninsula, East China: Constraints from T-t Paths Determined by U-Pb Thermochronology of Zircon and Apatite

Formation of large- and medium-sized Cretaceous volcanic reservoirs in the offshore Bohai Bay Basin, East China

Based on the geological and geophysical data of Mesozoic oil-gas exploration in the sea area of Bohai Bay Basin and the discovered high-yield volcanic oil and gas wells since 2019, this paper methodically summarizes the formation conditions of large- and medium-sized Cretaceous volcanic oil and gas reservoirs in the Bohai Sea. Research shows that the Mesozoic large intermediate-felsic lava and intermediate-felsic composite volcanic edifices in the Bohai Sea are the material basis for the formation of large-scale volcanic reservoirs. The upper subfacies of effusive facies and cryptoexplosive breccia subfacies of volcanic conduit facies of volcanic vent-proximal facies belts are favorable for large-scale volcanic reservoir formation. Two types of efficient reservoirs, characterized by high porosity and medium to low permeability, as well as medium porosity and medium to low permeability, are the core of the formation of large- and medium-sized volcanic reservoirs. The reservoir with high porosity and medium to low permeability is formed by intermediate-felsic vesicular lava or the cryptoexplosive breccia superimposed by intensive dissolution. The reservoir with medium porosity and medium to low permeability is formed by intense tectonism superimposed by fluid dissolution. Weathering and tectonic transformation are main formation mechanisms for large and medium-sized volcanic reservoirs in the study area. The low-source “source-reservoir draping type” is the optimum source-reservoir configuration relationship for large- and medium-sized volcanic reservoirs. There exists favorable volcanic facies, efficient reservoirs and source-reservoir draping configuration relationship on the periphery of Bozhong Sag, and the large intermediate-felsic lava and intermediate-felsic composite volcanic edifices close to strike-slip faults and their branch faults are the main directions of future exploration.

Subgroups of mild cognitive impairment based on cognitive function among Chinese older adults

Abstract Background: Due to the heterogeneity of mild cognitive impairment (MCI), the key points for nonpharmaceutical therapies cannot be determined. Examining impairment characteristics among different MCI subgroups would therefore be beneficial to the development of nonpharmaceutical therapies. Objective: To characterize the subgroups of older Chinese with MCI and examine factors associated with the membership of distinct subgroups. Methods: This cross-sectional study was conducted between October 2018 and June 2022 in Fujian, East China, with 1017 older adults with MCI deemed eligible. Exclusion criteria included any diagnosis of other neurological or psychiatric conditions that could affect cognition. Participants underwent a neuropsychological test that assessed memory, language, attention, and executive function(s) and completed a questionnaire collecting their socioeconomic and clinical variables. Neuropsychological test scores were transformed into z-scores, which were then examined using latent class analysis. Associations between socioeconomic and clinical variables, and MCI subgroups were assessed using multinomial logistic regression analysis. Results: Three MCI subgroups were identified: G1 “Minimally impairment” (56.64%), G2 “Moderate impairment” (36.28%), and G3 “Worst impairment” (7.08%). Age, place of residence, marriage status, living status, and participation in intellectual activities differed significantly across the 3 MCI subgroups (P<0.05). Compared with the minimally impairment group, participants with the worst impairment were less likely to participate in intellectual activity and more likely to live in a nursing home. Conclusion: Cognitive function is a suitable foundation for establishing classifications among individuals with MCI. Nonpharmalogical therapies may target older adults at higher risk of moderate or worst impairment.

Incidence trends and spatial distribution of thyroid cancer in the Chinese female population from 1990 to 2019

ObjectiveThis study aimed to analyze the incidence trends and spatial distribution characteristics of thyroid cancer among Chinese females from 1990 to 2019, thereby providing a scientific foundation and data support for the development of prevention and control policies. MethodsThyroid cancer incidence data from the Global Burden of Disease (GBD) research and the annual report from the Chinese Tumor Registration were utilized. The standardized thyroid cancer incidence rate among Chinese females 1990 to 2019 was described to understand the changes in developmental trends. The JoinPoint Regression Model was employed using Excel 2019, GraphPad Prism 8, JoinPoint Regression Program 4.8.0.1, and ArcGIS 10.2. ResultsThyroid cancer's standardized incidence among female Chinese continued to increase at 1.7% per year (annual average percentage change [AAPC] = 1.7, P < 0.001), and the spatial distribution was clustered. The main high-incidence areas were North, East, and Northwest China. ConclusionsThyroid cancer incidence in Chinese women is rapidly increasing, and its spatial distribution is concentrated. Strengthening monitoring, prevention, and control efforts in the relevant areas is warranted.

Geographical variation in dementia prevalence across China: a geospatial analysis

Dementia poses great health and social challenges in China. Dementia prevalence may vary across geographic areas, while comparable estimations on provincial level is lacking. This study aims to estimate dementia prevalence by provinces across China, taking into account risk factors of individual level and potential spatial correlation of provinces. In this study, 17,176 adults aged 50 years or older were included from the fourth wave of the ChinaHealth and Retirement Longitudinal Study (CHARLS 2018), covering 28 provinces, autonomous regions and municipalities. To improve provincial representativeness, we constructed provincial survey weights based on China 7th census (2020). The prevalence of dementia and 95% Bayesian credible intervals (BCIs) were estimated using a Bayesian conditional autoregressive (CAR) model with spatially varying coefficients of covariates. The weighted prevalence of dementia at provincial level in China in 2018 ranged from 2.62% (95%BCI: 1.70%, 3.91%) to 13.53% (95%BCI: 8.82%, 20.93%). High dementia prevalence was concentrated in North China, with a prominent high-high cluster, while provinces of low prevalence were concentrated on East and South China, characterized by a low-low cluster. Ordered by the median estimation of prevalence, the top 10% of provinces, include Xinjiang, Jilin, and Beijing. Meanwhile, Fujian, Zhejiang, and Guangdong rank among the last. The association between dementia prevalence and drinking, smoking, social isolation, physical inactivity, hearing impairment, hypertension, and diabetes exhibits provincial variation. Our study identifies a geospatial disparity in dementia prevalence and risk factor effects across China's provinces, with high-high and low-low clusters in some northern and southern provinces, respectively. The findings emphasize the need for targeted strategies, such as addressing hypertension and hearing impairment, in specific regions for more effective dementia prevention and treatment. National Science Foundation of China/the Economic and Social Research Council, UK Research and Innovation joint call: Understanding and Addressing Health and Social Challenges for Ageing in the UK and China. UK-China Health And Social Challenges Ageing Project (UKCHASCAP): present and future burden of dementia, and policy responses (grant number 72061137003, ES/T014377/1).

Differences in hydrocarbon accumulation and controlling factors of slope belt in graben basin: A case study of Pinghu Slope Belt in the Xihu sag of the east China Sea Shelf basin (ECSSB)

The Pinghu slope belt in the Xihu sag of the East China Sea Shelf Basin (ECSSB) is a crucial hydrocarbon production area in eastern China. However, due to the complex geological conditions, publications have lacked comprehensive research on the spatial-temporal coupling relationships of primary factors that impact hydrocarbon accumulation in the Pinghu slope belt. Furthermore, the hydrocarbon distribution patterns and the controlling factors across different study areas within the same slope belt are not yet fully understood. This study extensively utilized three-dimensional seismic data, well logging data, geochemical analysis, fluorescence analysis, and oil testing and production data to address these issues. Following a “stratification and differentiation” approach, the study identified seven distinct hydrocarbon migration and accumulation units (HMAU) in the Pinghu slope area based on the structural morphology characteristics, hydrocarbon source-reservoir-cap rock patterns, hydrocarbon migration pathways, and hydrocarbon supply range. Detailed analysis was conducted to examine the hydrocarbon distribution patterns and controlling factors within each migration and accumulation unit across different structural units, including high, medium, and low structural components. All data sources support a “southern‒northern sub-area division, eastern‒western sub-belt division, and variations in hydrocarbon accumulation” pattern in the Pinghu slope belt. The degree of hydrocarbon accumulation is controlled by the factors of structural morphology, hydrocarbon generation potential of source rocks, the spatial position of source slopes, fault sealing capacity, and sand body distribution. Furthermore, different coupling patterns of faults and sand bodies play a pivotal role in governing hydrocarbon enrichment systems across various migration and accumulation units. These observations indicate that three hydrocarbon accumulation patterns have been established within the slope belt, including near-source to far-source gentle slope with multiple hydrocarbon kitchens in the XP1−XP4 zones, near-source to middle-source gentle slope with dual-hydrocarbon kitchens in the XP5 zone, and near-source steep slope with a single hydrocarbon kitchen in the XP6−XP7 zones. These findings contribute to enhancing the theoretical system of hydrocarbon accumulation in the slope belt.

Decadal Variation in Winter‐Spring Thermal Front to the Zhejiang‐Fujian Coast and Its Mechanism

AbstractOff the east shore of China, thermal front plays a crucial role in modulating coastal biogeochemical environment. Based on multi‐source observational and reanalysis products, decadal variation and regulatory mechanism of Zhejiang‐Fujian coastal front (ZFCF) were investigated. The intensity of ZFCF showed a two‐stage inversed varying trend over past four decades: a downtrend from 1982 to 2002 followed by an uptrend from 2002 to 2022. During 1982–2002, sea surface temperature (SST) experienced more pronounced warming in inshore areas than offshore due to weakening of the southward coastal current, and this primarily led to the downtrend of ZFCF. Within 2002–2022, opposite SST trends were observed on two sides of ZFCF, that is, the ZFCF kept intensifying due to the cooperation of cooling inshore and warming offshore. The enhanced coastal current driven by stronger monsoon and increased Yangtze River discharge cooled the inshore area, then the cooling was further facilitated by intensified heat loss in the upper layer of the plume. Meanwhile, the onshore shift of Kuroshio led to strengthened intrusion of warm water into the East China Sea, heating the offshore side of ZFCF and thus intensifying the front.

Effect of dissolved organic nitrogen on the bloom of Prorocentrum donghaiense and Karenia spp. in the East China Sea coastal waters

Effect of dissolved organic nitrogen on the bloom of Prorocentrum donghaiense and Karenia spp. in the East China Sea coastal waters

Idiopathic hypertrophic pachymeningitis: Features of 9 patients and a literature review

Introduction: Idiopathic hypertrophic pachymeningitis (IHP) is a rare disorder presenting with headache, cranial and spinal neuropathy. This study is to explore the clinical, laboratory and imaging changes; treatment; and clinical outcomes of idiopathic hypertrophic pachymeningitis (IHP). Methods: This was a retrospective evaluation of 9 patients (5 men and 4 women; mean age: 53.6 years), their clinical features, laboratory tests, cerebral spinal fluid (CSF) analysis, MRI results, pathological features, treatment and clinical outcomes from a tertiary centre in Qingdao, North East China. The serum IgG4 was negative for all the cases. Results: Headache was the most common symptom (7/9), followed by oculomotor, trigeminal, abducens and facial nerve neuropathies, and limb numbness in one case. Two cases showed increased ESR and CRP, and four were positive for ANA or anti-SSA antibodies. On CSF analysis, 2/7 had increased pressure, and 4/7 showed lymphocytosis and high protein levels. MRI revealed a thickening and enhancement of the dura, mainly involving bilateral tentorium (85%), falx cerebri (57%), and cerebellar hemisphere (57%). The tissue biopsy of dura mater in three cases showed thickened collagen fibers, lymphocytosis and focal necrosis, with similar but not identical features to IgG4-related sclerosing disease. Most patients were treated with corticosteroids, and 79% showed improvement. The abnormal thickness and enhancement of the dura mater disappeared in one case. Conclusion: Gadolinium-enhanced MRI serves as the key preliminary investigation for the diagnosis and evaluation of the clinical course for IHP. Majority of patients have good respond to steroid.

A mechanism of enhanced subsurface near-inertial kinetic energy in the East China Sea associated with successive typhoons

Near-inertial waves (NIWs) play an important role in diapycnal processes and energy dissipation. A mooring observation deployed on the continental shelf in the East China Sea captured anomalously intensified subsurface near-inertial kinetic energy (NIKE) during the passage of Typhoon Danas (2013). An early study has investigated the role of Parametric Subharmonic Instability (PSI) induced by internal tides in the intensification of the subsurface intensified near-inertial velocity. However, results based on regional numerical simulations reveal that strong subsurface near-inertial velocity persists even in the absence of tidal effects, implying the existence of additional sources of NIWs. Our analyses showed that after excluding the effect of PSI, approximately 30% of the remaining subsurface NIKE can be attributed to another Typhoon Fitow (2013), which occurred a week prior to Typhoon Danas. Constrained by the Kuroshio current and the continental shelf, the NIKE generated by Typhoon Fitow propagates northward and reaches the mooring location, leading to the intensified subsurface NIW signal. Our simulation, together with the observations, suggests complicated NIW dynamics in continental shelf regions, involving interactions between successive typhoons, topography and background current, and differing from the open ocean. These interactions will further influence vertical mixing on the continental shelf along the pathway of NIW.

Surface Reconstruction of Silicone-Based Amphiphilic Polymers for Mitigating Marine Biofouling.

Poly(dimethylsiloxane) (PDMS) coatings are considered to be environmentally friendly antifouling coatings. However, the presence of hydrophobic surfaces can enhance the adhesion rate of proteins, bacteria and microalgae, posing a challenge for biofouling removal. In this study, hydrophilic polymer chains were synthesised from methyl methacrylate (MMA), Poly(ethylene glycol) methyl ether methacrylate (PEG-MA) and 3-(trimethoxysilyl) propyl methacrylate (TPMA). The crosslinking reaction between TPMA and PDMS results in the formation of a silicone-based amphiphilic co-network with surface reconstruction properties. The hydrophilic and hydrophobic domains are covalently bonded by condensation reactions, while the hydrophilic polymers migrate under water to induce surface reconstruction and form hydrogen bonds with water molecules to form a dense hydrated layer. This design effectively mitigates the adhesion of proteins, bacteria, algae and other marine organisms to the coating. The antifouling performance of the coatings was evaluated by assessing their adhesion rates to proteins (BSA-FITC), bacteria (B. subtilis and P. ruthenica) and algae (P. tricornutum). The results show that the amphiphilic co-network coating (e.g., P-AM-15) exhibits excellent antifouling properties against protein, bacterial and microalgal fouling. Furthermore, an overall assessment of its antifouling performance and stability was conducted in the East China Sea from 16 May to 12 September 2023, which showed that this silicon-based amphiphilic co-network coating remained intact with almost no marine organisms adhering to it. This study provides a novel approach for the development of high-performance silicone-based antifouling coatings.

Research on multiscale OpenStreetMap in China: data quality assessment with EWM-TOPSIS and GDP modeling

ABSTRACT OpenStreetMap (OSM) is a voluntary platform designed to provide free and up-to-date geographic data. Since OSM is based on multisource geographic data provided by the public, the quality of the data has become a concern of researchers. In this study, a unified measure for evaluating OSM data quality was constructed, and the entropy weight method (EWM) and Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) model were used to evaluate the quality of multiscale OSM data in China from 2014 to 2020. In addition to evaluating the data quality, the use of OSM data quality index factors in economic modeling at different spatial scales in China was explored by using a geographic information system (GIS) analysis method and a geographically and temporally weighted regression (GTWR) model. Four machine learning models, SVM, RF, XGBoost and CatBoost, were used to simulate the grid-scale GDP, and the effectiveness of these simulations was discussed. The results showed that (1) the weights of OSM data quality indicator factors vary across different spatial scales. (2) From 2014 to 2020, the quality of national-scale OSM data first increased, then decreased and then gradually stabilized. In addition, the quality of OSM data at the provincial and municipal scales is significantly different, and the distribution is affected by the population and geographical environment. (3) Over time, the spatial clustering characteristics of OSM data quality at different spatial scales in China has continuously strengthened. In addition, the quality of Chinese OSM data displays obvious local spatial autocorrelation characteristics, which are dominated by H-H clustering and L-L clustering. (4) The GTWR model performs well in predicting and revealing the spatiotemporal correlation characteristics between GDP and OSM data quality indicators at the provincial and municipal scales in China. The correlations increase with decreasing spatial scale (provincial to municipal). Moreover, the GDP modeling ability is better in economically underdeveloped Northwest China and economically developed East China. (5) Four machine learning models coupled with road network length completeness, relative linear density, road name attribute completeness, POI name attribute completeness, road network accuracy, road network update frequency, POI update frequency, topological consistency and directional similarity yielded the best grid-scale GDP simulation values. Notably, the CatBoost model provided the best accuracy, and the results further verified that it is feasible to use the proposed OSM data quality index system to predict the regional economic development level in China.

Contribution of Atmospheric Factors in Predicting Sea Surface Temperature in the East China Sea Using the Random Forest and SA-ConvLSTM Model

Atmospheric forcings are significant physical factors that influence the variation of sea surface temperature (SST) and are often used as essential input variables for ocean numerical models. However, their contribution to the prediction of SST based on machine-learning methods still needs to be tested. This study presents a prediction model for SST in the East China Sea (ECS) using two machine-learning methods: Random Forest and SA-ConvLSTM algorithms. According to the Random Forest feature importance scores and correlation coefficients R, 2 m air temperature and longwave radiation were selected as the two most important key atmospheric factors that can affect the SST prediction performance of machine-learning methods. Four datasets were constructed as input to SA-ConvLSTM: SST-only, SST-T2m, SST-LWR, and SST-T2m-LWR. Using the SST-T2m and SST-LWR, the prediction skill of the model can be improved by about 9.9% and 9.43% for the RMSE and by about 8.97% and 8.21% for the MAE, respectively. Using the SST-T2m-LWR dataset, the model’s prediction skill can be improved by 10.75% for RMSE and 9.06% for MAE. The SA-ConvLSTM can represent the SST in ECS well, but with the highest RMSE and AE in summer. The findings of the presented study requires much more exploration in future studies.

Hospitalization information and burden of pediatric inpatients in transport accidents

BackgroundTransport accidents are one of the leading causes of child morbidity and mortality worldwide and represent a significant public health burden. This study aimed to investigate the hospitalization information and burden of pediatric inpatients in transport accidents in China.MethodsIn this study, we collected the cover page of the medical records of pediatric inpatients in transport accidents using the Futang Research Center of Pediatric Development (FRCPD) database from January 1, 2016 to December 31, 2021. Then, we extracted the epidemiological characteristics, including demographic characteristics, cases distribution, disease information, and hospitalization burden.ResultsAmong 36,455 included inpatients, males, aged 1–3 years, East China, July were dominant in different subgroups. In transport accidents, pedestrians were the most frequently type of injury (65.69%). Of all known lesions, craniocerebral/nerve injury was the more common results in pediatric inpatients in transport accidents (33.93%). In addition to pedal cyclists more susceptible to sport system injury, other types of injured person with transport accidents were mainly craniocerebral/nerve injury. In terms of the type of discharge, occupant of heavy transport vehicle or bus and people with craniocerebral/nerve injury had the highest mortality rate after hospitalization in all type and lesion of injured person groups, respectively. The largest hospitalization burden in the type of injured person was occupant of heavy transport vehicle or bus.ConclusionsThis study revealed that epidemiological characteristics and the main factor influencing the hospitalization information and burden of children with traffic accidents in China.

Distribution of volatile organic compounds (VOCs) in the urban atmosphere of Hangzhou, East China: Temporal variation, source attribution, and impact on the secondary formations of ozone and aerosol

Distribution of volatile organic compounds (VOCs) in the urban atmosphere of Hangzhou, East China: Temporal variation, source attribution, and impact on the secondary formations of ozone and aerosol

Ocean acidification alters microeukaryotic and bacterial food web interactions in a eutrophic subtropical mesocosm

Ocean acidification (OA) is known to influence biological and ecological processes, mainly focusing on its impacts on single species, but little has been documented on how OA may alter plankton community interactions. Here, we conducted a mesocosm experiment with ambient (∼410 ppmv) and high (1000 ppmv) CO2 concentrations in a subtropical eutrophic region of the East China Sea and examined the community dynamics of microeukaryotes, bacterioplankton and microeukaryote-attached bacteria in the enclosed coastal seawater. The OA treatment with elevated CO2 affected taxa as the phytoplankton bloom stages progressed, with a 72.89% decrease in relative abundance of the protist Cercozoa on day 10 and a 322% increase in relative abundance of Stramenopile dominated by diatoms, accompanied by a 29.54% decrease in relative abundance of attached Alphaproteobacteria on day 28. Our study revealed that protozoans with different prey preferences had differing sensitivity to high CO2, and attached bacteria were more significantly affected by high CO2 compared to bacterioplankton. Our findings indicate that high CO2 changed the co-occurrence network complexity and stability of microeukaryotes more than those of bacteria. Furthermore, high CO2 was found to alter the proportions of potential interactions between phytoplankton and their predators, as well as microeukaryotes and their attached bacteria in the networks. The changes in the relative abundances and interactions of microeukaryotes between their predators in response to high CO2 revealed in our study suggest that high CO2 may have profound impacts on marine food webs.

PDO influenced interdecadal summer precipitation change over East China in mid-18th century

There have been few case studies of the relationship between the Pacific Decadal Oscillation (PDO) and the East Asian climate before the pre-industrial era with limited anthropogenic impacts. Using the CESM Last Millennium Ensemble (CESM-LME) simulation with reconstruction evidence, we showed that there was an interdecadal transition of the summer precipitation in East China, with the pattern of “southern flooding and northern drought” in the mid-18th century. The interdecadal transition was influenced by PDO, as suggested by both the reconstruction evidence and simulation. Corresponding to the positive PDO phase change, the East Asia-Pacific pattern teleconnection wave train propagated northward and modulated the circulation and precipitation in East China, together with the southward movement of the East Asian westerly jet. The volcanic double or clustered eruptions are thought to have played a crucial role on the shift of the PDO phase and the decadal summer climate change over East China during the mid-18th century. Incorporating volcanic activity in a reasonable manner would likely improve decadal simulations of East Asian climate in the past and predictions in the future.

Eocene to Miocene sediment provenance features and evolution history of the western slope area in the Xihu Sag of the East China Sea Continental Shelf Basin

Rift basins are commonly characterised by multiple sediment sources (e.g. transverse and longitudinal) that change over time during different rifting evolution stages. Therefore, tracing sediment provenance to decipher the sedimentary source-to-sink analyses processes in rift basins is important to predict sandy reservoirs. The Xihu Sag in the East China Sea Shelf Basin, particularly its western slope, features large-scale sand bodies of unclear origin. We used petrography, heavy minerals and geochemistry to study sediment provenance in the Eocene Baoshi to Miocene Longjing formations. Our work suggests there are three distinct areas (namely zones A, B and C) affected by different source areas. Zone A, influenced by the Hupijiao uplift, primarily contains metamorphic rock minerals; Zone B, affected by the Haijiao and Hupijiao uplifts, contains igneous and metamorphic rock minerals; and Zone C, dominated by the Haijiao uplift, features igneous with some metamorphic sources, which increase over time, indicating stronger sediment input from the northern Hupijiao uplift. Rare earth element analysis suggests a continental margin and island arc setting, primarily with intermediate–acid felsic rock sources. However, a Eu negative anomaly in Eocene upper Pinghu Formation to the Miocene Longjing Formation indicates some basic source contributions, possibly from a volcanic belt east of the South Yellow Sea. This intermediate–basic volcanic rock belt is located to the northwest of the Hupijiao uplift and may provide clasts for zones A and B through axial channels. These findings indicate that varied sediment sources in the different zones and basin evolution stages with a growing extra-basinal contribution from the Eocene to Miocene, which align with the tectonic shift from the rifting to post-rift period, are essential for understanding the sedimentary filling in this area.

Mussel Culture Activities Facilitate the Export and Burial of Particulate Organic Carbon

The recent expansion of shellfish mariculture could significantly impact the ocean carbon cycle and its associated biogeochemical processes. To understand the source and fate of particulate organic carbon (POC), a summer cruise was conducted from September 8 to 10, 2022, at a mussel farm on Gouqi Island and its adjacent areas located in the East China Sea. Parameters included in situ temperature and salinity, contents of dissolved oxygen (DO), suspended particulate matter (SPM), POC, and chlorophyll a (Chl a), as well as the stable carbon isotopic composition (δ13C) of organic matter in particle and sediment samples, which were analyzed to facilitate a comparative assessment of the areas inside and outside the mussel farm. The POM was much fresher (POC/Chl a &lt; 150) inside the farm with little impact from sediment resuspension (lower SPM content, 11.6 ± 6.6 mg/L), while a significant influence of sediment resuspension was found outside the farm (SPM &gt; 20 mg/L, POC/Chl a &gt; 150). A two end-member mixing model showed that 82.0 ± 6.0% of POC originated from marine algae within the farm, much higher than that outside the farming area (66.1 ± 7.8%). Moreover, elevated DO saturation but relatively low Chl a concentration within the farm suggested continuous algae consumption following potential high productivity. The averaged δ13C values were similar among suspended POC, sinking POC, and sedimentary organic carbon within the farm, implying the fast export and burial of POC. This is likely due to the filter-feeding habits of mussels, who ingest fresh POC and then pack it as fecal pellets that rapidly settle into the sediment. This study sheds light on the distribution and sources of POM inside and outside the mussel farm on Gouqi Island, enhancing our understanding of the marine carbon cycle on shellfish farms and providing insights into the underlying biogeochemical processes.

Predictive Model for EV Charging Load Incorporating Multimodal Travel Behavior and Microscopic Traffic Simulation

A predictive model for the spatiotemporal distribution of electric vehicle (EV) charging load is proposed in this paper, considering multimodal travel behavior and microscopic traffic simulation. Firstly, the characteristic variables of travel time are fitted using advanced techniques such as Gaussian mixture distribution. Simultaneously, the user’s multimodal travel behavior is delineated by introducing travel purpose transfer probabilities, thus establishing a comprehensive travel spatiotemporal model. Secondly, the improved Floyd algorithm is employed to select the optimal path, taking into account various factors including signal light status, vehicle speed, and the position of starting and ending sections. Moreover, the approach of multi-lane lane change following and the utilization of cellular automata theory are introduced. To establish a microscopic traffic simulation model, a real-time energy consumption model is integrated with the aforementioned techniques. Thirdly, the minimum regret value is leveraged in conjunction with various other factors, including driving purpose, charging station electricity price, parking cost, and more, to simulate the decision-making process of users regarding charging stations. Subsequently, an EV charging load predictive framework is proposed based on the approach driven by electricity prices and real-time interaction of coupled network information. Finally, this paper conducts large-scale simulations to analyze the spatiotemporal distribution characteristics of EV charging load using a regional transportation network in East China and a typical power distribution network as case studies, thereby validating the feasibility of the proposed method.