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Comprehensive review on green synthesis of bio-based 2,5-furandicarboxylic acid Lei ZHAO, Zelin LI, Bolong LI, Shuchang BIAN, Jianhua WANG, Hailan ZHANG, Chen ZHAO Journal of East China Normal University(Natural Science)    2023, 2023 (1): 160-169.   DOI: 10.3969/j.issn.1000-5641.2023.01.016 Abstract （2060）   HTML （94）    PDF （1090KB）（1278）       Knowledge map    Bio-based 2,5-furandicarboxylic acid (FDCA) is expected to partially replace petroleum-based terephthalic acid (PTA) for the synthesis of high-performance polymer materials. This review article summarizes the latest achievements on the various synthesis routes of FDCA from 5-hydroxymethylfurfural (HMF), furoic acid, furan, diglycolic acid, hexaric acid, 2,5-dimethylfuran, and 2-methylfuran. In particular, the direct oxidation, heterogeneous thermal catalytic oxidation, photoelectric catalytic oxidation of HMF and furoic acid carboxylation, disproportionation, carbonylation, and other routes to synthesize FDCA are reviewed in detail. Based on the comparative analysis of the advantages and disadvantages of each route, the HMF route and the furoic acid route are considered the most promising candidates for the large-scale production of FDCA. Further exploration and future research should be carried out to improve the catalytic production and separation efficiency of FDCA, simplify the reaction process, and reduce production wastes. Table and Figures | Reference | Related Articles | Metrics

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Application of Cu-based catalysts in the electroreduction of carbon dioxide Jing TANG, Zining ZHANG, Xiang ZHENG Journal of East China Normal University(Natural Science)    2023, 2023 (1): 149-159.   DOI: 10.3969/j.issn.1000-5641.2023.01.015 Abstract （1141）   HTML （39）    PDF （1081KB）（713）       Knowledge map    To achieve the national strategy of carbon neutralization, the electroreduction of carbon dioxide into usable reagents via renewable energy has caused widespread concern in the scientific community. Cu-based electrocatalysts can reduce carbon dioxide to high value-added multi carbon products, but the catalytic mechanism still needs to be studied to improve its selectivity and efficiency. Depending on the state of the Cu, Cu-based catalysts can be divided into Cu alloy/composite catalysts, single-atom, oriented crystalline, and oxidized Cu-based catalysts. This paper introduced the common preparation methods, structural characteristics, effect of electro catalytic reduction of carbon dioxide, and possible catalytic mechanism of the four types of Cu-based catalysts mentioned above. Table and Figures | Reference | Related Articles | Metrics

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Survey of few-shot instance segmentation methods Xueming ZHOU, Dingjiang HUANG Journal of East China Normal University(Natural Science)    2022, 2022 (5): 136-146.   DOI: 10.3969/j.issn.1000-5641.2022.05.012 Abstract （916）   HTML （25）    PDF （968KB）（433）       Knowledge map    Instance segmentation is an important task in computer vision. In recent years, the development of meta- and few-shot learning has promoted the combination of computer vision learning tasks, which has overcome the bottleneck of detection and classification with regard to objects that are difficult to manually label and those with high labeling costs. Although great progress has been made with few-shot semantic segmentation and object detection, instance segmentation based on few-shot learning has not become a research hotspot until very recently. Beginning with an overview of few-shot instance segmentation, existing approaches are divided into categories of anchor-based and anchor-free algorithms. The architectures and primary technologies behind those approaches are respectively discussed, and common datasets and evaluation indices are described. Additionally, advantages and disadvantages of algorithm performance are analyzed, and future development directions and challenges are presented. Table and Figures | Reference | Related Articles | Metrics

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Natural products: A bridge between new targets and novel pesticide discovery Zhengqi FANG, Shuanhu GAO, Haibing HE Journal of East China Normal University(Natural Science)    2023, 2023 (1): 21-30.   DOI: 10.3969/j.issn.1000-5641.2023.01.003 Abstract （883）   HTML （40）    PDF （3235KB）（497）       Knowledge map    Pesticides are important tools to control crop diseases and pest hazards, guaranteeing the crop harvest. Natural products and their derivatives are major sources of novel pesticides and play indispensable roles in various fields, such as insecticide, fungicide, plant growth regulation, immune regulation and so on. In recent years, numerous fields of biotechnology have made great progress, like genomics, proteomics and structural biology. And thus, the identification of pesticide targets based on natural products and the creation of novel pesticide molecules based on target structures developed rapidly. The concept, rational design, received more attention in pesticide creation. In this article, the discovery of active natural products based on existed targets or novel targets verifying by natural products were demonstrated by several cases, and the subsequent progress in the development of new pesticides were also discussed. The cases explained the important role of natural products in bridging new targets and novel pesticides. Table and Figures | Reference | Related Articles | Metrics

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Research progress on pollution and degradation of plastic waste Kaizhen MIAO, Jiaolong MENG, Xuefeng JIANG Journal of East China Normal University(Natural Science)    2023, 2023 (1): 170-176.   DOI: 10.3969/j.issn.1000-5641.2023.01.017 Abstract （859）   HTML （44）    PDF （1177KB）（458）       Knowledge map    Plastics are widely used in daily life owing to their light weight, portability, and affordability. However, post-consumer-waste plastics do not degrade easily in the natural environment, making plastic pollution a new global environmental issue. Thus, exploration in the field of plastic degradation has increased in recent years. To promote the treatment of plastic waste and provide a scientific reference for environmental protection and sustainable development, this study describes the current state of plastic pollution. It also systematically summarizes various research fields of plastic degradation and presents the development prospect of photocatalysis and bio-based plastics in the future. Table and Figures | Reference | Related Articles | Metrics

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Review of zeolite-confined subnanometric cluster catalysts Yue MA, Hao XU, Yueming LIU, Kun ZHANG, Peng WU, Mingyuan HE Journal of East China Normal University(Natural Science)    2023, 2023 (1): 82-94.   DOI: 10.3969/j.issn.1000-5641.2022.00.009 Abstract （675）   HTML （26）    PDF （5085KB）（525）       Knowledge map    The design of efficient and stable supported metal catalysts to prevent metal species from sintering into large nanoparticles under harsh preparation and reaction conditions is key for various important processes, including the conversion of C1 resources and dehydrogenation of low carbon alkanes to C2 and C3 olefins. Zeolites with uniform subnano micropores and various three-dimensional crystalline structures have been proven as ideal supports for preparing highly efficient and stable metal catalysts via encapsulating subnanometric metal clusters within their pores, cages, and channels. Interactions between metal clusters and the zeolite skeleton can regulate their geometric and electronic structure. The development of zeolite-confined subnanometric cluster catalysts aims to take advantage of this joint confinement effect and induce synergy between guest metal species and active sites in host zeolite frameworks. This can further improve the catalytic activity of resultant composite catalysts, for applications in multiple catalytic reaction processes . In this review, typical preparation methods of zeolite-confined subnanometric clusters and their catalytic applications in selective hydrogenation of CO2 and alkynes, hydrogen generation by formic acid decomposition and ammonia borane hydrolysis, and propane dehydrogenation to propene are discussed. Table and Figures | Reference | Related Articles | Metrics

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Prediction of remaining useful life of aeroengines based on the Transformer with multi-feature fusion Yilin MA, Huiling TAO, Qiwen DONG, Ye WANG Journal of East China Normal University(Natural Science)    2022, 2022 (5): 219-232.   DOI: 10.3969/j.issn.1000-5641.2022.05.018 Abstract （668）   HTML （31）    PDF （1754KB）（610）       Knowledge map    As the core components of aircraft, engines play a vital role during flight. Accurate prediction of the remaining useful life of the aeroengine can help prognostics and health management, thus preventing major accidents and saving maintenance costs. In view of the lack of consideration of different time steps and the relationship between different sensors and operating conditions in existing methods, a remaining useful life prediction method based on the Transformer was proposed, which fuses multi-feature outputs from different encoder layers. This method selects two input data with different time steps, analyzes the relationship between the sensors using permutation entropy, and extracts features independently from the operating condition data. The experimental results on the public aeroengine dataset CMAPSS (Commercial Modular Aero-Propulsion System Simulation) show that the proposed method is superior to other advanced remaining useful life prediction methods. Table and Figures | Reference | Related Articles | Metrics

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3D obstacle-avoidance for a unmanned aerial vehicle based on the improved artificial potential field method Lanfeng ZHOU, Mingyue KONG Journal of East China Normal University(Natural Science)    2022, 2022 (6): 54-67.   DOI: 10.3969/j.issn.1000-5641.2022.06.007 Abstract （668）   HTML （21）    PDF （2858KB）（455）       Knowledge map    This paper aims to address the challenge of seeking an optimal safe path for a UAV (unmanned aerial vehicle) from an initial position to a target position, while avoiding all obstacles in a three-dimensional environment. An improved APF (artificial potential field) method combined with the regular hexagon guidance method is proposed to solve unreachable and local minimum problems near obstacles as observed with traditional artificial potential field methods. First, we add a distance correction factor to the repulsive potential field function to solve problems associated with unreachable targets. Then, a regular hexagon-guided method is proposed to improve the local minimum problem. This method can judge the environment when the UAV is trapped in a local minimum point or trap area and select the appropriate planning method to guide the UAV to escape from the local minimum area. Then, 3D modeling and simulation were carried out via Matlab, taking into account a variety of scenes involving complex obstacles. The results show that this method has good feasibility and effectiveness in real-time path planning of UAVs. Lastly, we demonstrate the performance of the proposed method in a real environment, and the experimental results show that the proposed method can effectively avoid obstacles and find the optimal path. Table and Figures | Reference | Related Articles | Metrics

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Research on user behavior portrait and subject mining in the express logistics field during Coronavirus epidemic Jiling LI, Baolin LI, Songru YAN Journal of East China Normal University(Natural Science)    2022, 2022 (5): 100-114.   DOI: 10.3969/j.issn.1000-5641.2022.05.009 Abstract （613）   HTML （19）    PDF （1321KB）（230）       Knowledge map    Based on logistics-field blog post data from Weibo from November 2019 to May 2022, the user behaviors of express logistics services in the context of the Coronavirus epidemic are profiled. Using grounded theory and abstract clustering methods, five user behaviors and 22 subject contents are abstracted, and the corresponding user profile is generated. This paper further discusses the subject contents, the subject evolution, and the analysis of group differences. The results show that user satisfaction with logistics services was similar, and the dissatisfaction was diversified with obvious escalation. Variables of transportation efficiency and logistics guarantee were the main factors affecting the evaluation, and the development of the epidemic affected the concerns and attitudes of the subject contents, which had obvious group differences at different degrees. Table and Figures | Reference | Related Articles | Metrics

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Progress in synthesis of methyl glyoxylate by selective oxidation of methyl glycolate with molecular oxygen Hao WANG, Guofeng ZHAO, Yong LU Journal of East China Normal University(Natural Science)    2023, 2023 (1): 104-113.   DOI: 10.3969/j.issn.1000-5641.2023.01.011 Abstract （610）   HTML （8）    PDF （834KB）（408）       Knowledge map    Methyl glyoxylate is widely used in organic synthesis and chemical production. The application of traditional preparation methods is limited by high cost, low efficiency, and significant environmental pollution. During the coal to ethylene glycol process, methyl glycolate is produced as an intermediate product of the hydrogenation of dimethyl oxalate (DMO) to ethylene glycol. Methyl glycolate can be selectively obtained from DMO via hydrogenation, and therefore, has the potential to serve as raw material for methyl glyoxylate. However, only few studies have considered this process. Herein , the applications, traditional preparation methods, and state-of-the-art research progress of methyl glycolate oxidation are reviewed. Recent research on selective oxidation of related alcohols (such as ethanol) to aldehydes and ketones is also summarized. Table and Figures | Reference | Related Articles | Metrics

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Electrodeposition performance of a copper-based catalyst for the electroreduction of CO2 Meng’en CHU, Chunjun CHEN, Haihong WU, Mingyuan HE, Buxing HAN Journal of East China Normal University(Natural Science)    2023, 2023 (1): 129-139.   DOI: 10.3969/j.issn.1000-5641.2023.01.013 Abstract （605）   HTML （23）    PDF （4857KB）（479）       Knowledge map    To improve the catalytic performance of copper-based catalysts in the electroreduction of CO2, nitrotriacetic acid (NTA) was used as an additive to prepare copper-based catalysts having a three-dimensional structure by applying electrodeposition. The prepared catalysts exhibited excellent selectivity and activity for the electroreduction of CO2 to multi-carbon (C2+) products. At –1.26 V vs. RHE, the faradaic efficiency of C2H4 and C2+ products over the Cu-0.5/CP electrode reached 44.0% and 61.6%, respectively, and the total current density reached 12.3 mA·cm–2. In addition, Pd- and Zn-based catalysts were prepared by employing electrodeposition; the results showed that their selectivity for CO was significantly improved, proving that NTA has a certain universality in the preparation of electrocatalysts by using electrodeposition. Table and Figures | Reference | Related Articles | Metrics

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Research on diagnosis of leukemia by flow detection based on quantum dot coded microspheres Junfei YANG, Yeying WANG, Jing’e ZHOU, Jing WANG, Zhiqiang YAN, Lei YU Journal of East China Normal University(Natural Science)    2022, 2022 (6): 139-149.   DOI: 10.3969/j.issn.1000-5641.2022.06.014 Abstract （563）   HTML （6）    PDF （2251KB）（164）       Knowledge map    In this work, micro-scale porous carboxyl polystyrene microspheres (PS) were prepared using seed polymerization. Quantum dots (QDs) were used as fluorescent molecules to synthesize QDs with different emission wavelengths and successfully loaded into porous microspheres to form fluorescent coding microspheres (QDs@PS). Subsequently, serum samples of patients with acute leukemia (AL) were detected, and the antigen in the serum was quantitatively analyzed using flow cytometry. Scanning electron microscope (SEM) and flow cytometry images showed that the microspheres were regular and uniform in size. Fluorescence microscopy showed that the QDs permeated uniformly into the whole microsphere. In addition, QDs@PS showed good fluorescence stability, no QD leakage was observed, and the QDs@PS maintained its fluorescence for a period of at least two weeks. The use of fluorescence spectroscopic analysis for the detection of human immunoglobulin G (IgG) showed that the carboxyl groups on the surface of fluorescent microspheres are beneficial for the efficient covalent binding of biological macromolecules, which can be used for sandwich immunosandwich reaction coupling with leukemic high expression antigen interleukin 6 (IL-6). Combined with serum samples from leukemia patients, the fluorescence of QDs was detected by flow cytometry, and the mean fluorescence intensity (MFI) was calculated to determine the content of IL-6 in the serum. These results indicate that the designed optically-encoded microcarrier can be successfully applied to high-throughput and multichannel biomolecular analysis and has great potential in blood disease detection and diagnosis. Table and Figures | Reference | Related Articles | Metrics

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Personalized course recommendations based on a learner’s knowledge and personality Qimin BAN, Wen WU, Wenxin HU, Hui LIN, Wei ZHENG, Liang HE Journal of East China Normal University(Natural Science)    2022, 2022 (6): 87-101.   DOI: 10.3969/j.issn.1000-5641.2022.06.010 Abstract （540）   HTML （14）    PDF （1363KB）（233）       Knowledge map    Adaptive learning is an educational method that uses computer algorithms to coordinate interaction with learners, and provides customized learning resources and learning activities to address the unique needs of each learner. With the impact of COVID-19, adaptive learning has become increasingly important. One of the challenges with adaptive learning is how to provide personalized learning resources for learners—i.e., how to generate personalized recommendation for learners from a large set of learning resources. Existing methodologies mainly generate recommendations based on a learner’s knowledge level; however, this approach has some limitations. Firstly, when assessing a learner’s knowledge level, learners’ forgetting phenomenon has to date not been well modeled. Secondly, recommendations are generated separately from knowledge tracing tasks, ignoring the interconnectedness between these aspects. In addition, learners’ preferences for the type of learning resources and learning strategies is normally ignored if the knowledge level alone is used. To solve the aforementioned problems, this paper proposes a knowledge and personality incorporated multi-task learning framework (KPM) to boost course recommendations (i.e., the above-mentioned learning resources); the proposed method regards an enhanced knowledge tracing task (EKTT) as an auxiliary task to assist the primary course recommendation task (CRT). Specifically, using EKTT, we design a personalized forgetting controller to enhance the deep knowledge tracing model for accurately assessing a learner’s knowledge level. With CRT, we combine the learner’s knowledge level and sequential behavior with their personality adapted to the specific context to obtain learner’s profile; this data is subsequently used to generate a course recommendation list. Experimental results on real-world educational datasets demonstrate the superiority of our proposed method in terms of hit ratio (HR), normalized discounted cumulative gain (NDCG), and precision, indicating that our method can generate more personalized recommendations. Table and Figures | Reference | Related Articles | Metrics

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Spatial and temporal distribution of Tettigonioidea and Grylloidea at different altitudes of Tianmu Mountain Zhuqing HE, Xinyi LIAO, Nuo DING Journal of East China Normal University(Natural Science)    2022, 2022 (6): 123-129.   DOI: 10.3969/j.issn.1000-5641.2022.06.012 Abstract （442）   HTML （6）    PDF （865KB）（203）       Knowledge map    In this research, we carried out a survey based on one fixed transect for Tettigonioidea and Grylloidea insects distributed in Tianmu Mountain from April to October of 2019. The results showed that there were 28 species of Tettigonioidea and 19 species of Grylloidea in Tianmu Mountain. Among them, six species of Tettigonioidea and eight species of Grylloidea were recorded in Tianmu Mountain for the first time. The insects became adults in August, September, and October. The insects distributed at lower altitudes tended to become adults earlier than those at higher altitudes. The number of species declined initially with increasing altitude, and subsequently increased. The Tettigonioidea species are distributed at various altitudes while Grylloidea species are primarily distributed at low altitudes. Because Truljalia tylacantha, Ruidocollaris truncatolobata, Goniogryllus punctatus and some other species are only distributed in a narrow scope at high altitudes, they can be used as indicator species for climate change in Tianmu Mountain. Table and Figures | Reference | Related Articles | Metrics

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Automatic generation of Web front-end code based on UI images Jin GE, Xuesong LU Journal of East China Normal University(Natural Science)    2023, 2023 (5): 100-109.   DOI: 10.3969/j.issn.1000-5641.2023.05.009 Abstract （433）   HTML （16）    PDF （1748KB）（180）       Knowledge map    User interfaces (UIs) play a vital role in the interactions between an application and its users. The current popularity of mobile Internet has led to the large-scale migration of web-based applications from desktop to mobile. Web front-end development has become more extensive and in-depth in application development. Traditional web front-end development relies on designers to give initial design drafts and then programmers to write the corresponding UI code. This method has high industry barriers and slow development, which are not conducive to rapid product iteration. The development of deep learning makes it possible to automatically generate web front-end code based on UI images. Existing methods poorly capture the features of UI images, and the accuracy of the generated code is low. To mitigate these problems, we propose an encoder–decoder model, called image2code, based on the Swin Transformer, which is used to generate web front-end code from UI images. Image2code regards the process of generating web front-end code from UI images as an image captioning task and uses Swin Transformer with a sliding window design as the backbone network of the encoder and decoder. The sliding window operation limits the attention calculation to one window, which reduces the amount of calculation by the attention mechanism while simultaneously ensuring that feature connections remain across windows. In addition, image2code generates Emmet code, which is much simpler and can be directly converted to HTML code, improving the efficiency of model training. Experimental results show that image2code performs better than existing representative models, such as pix2code and image2emmet, in the task of web front-end code generation on existing and newly constructed datasets. Table and Figures | Reference | Related Articles | Metrics

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Diversity of plants in Chinese Taoist temples and the distribution pattern of Taoist tree species Wei CHANG, Yongchuan YANG, Cheng JIN, Xinyang WANG, Li HUANG, Lihua ZHOU, Siwei HU Journal of East China Normal University(Natural Science)    2023, 2023 (3): 9-19.   DOI: 10.3969/j.issn.1000-5641.2023.03.002 Abstract （429）   HTML （247）    PDF （1768KB）（173）       Knowledge map    In this study, we obtained tree species from 72 Taoist temples across China. We subsequently documented the tree species composition, distribution pattern, and impact factors in different regions to determine the role of Taoist temples in biodiversity protection. The results showed that: ① Among 72 Taoist temples sampled across China, we observed a total of 354 species of trees, belonging to 85 families and 208 genera; ② The tree species in the Taoist temples were mainly native species, and the mean value for the proportion of native species in each Taoist temple was 62.5%±19.8% (mean ± standard deviation). Most of the Taoist temples (77.8%), moreover, housed threatened tree species; ③ Taoist tree species originated largely from subtropical regions, with the Yangtze River Basin being the most represented, especially in the southwest and south-central regions where a relatively large proportion of ethnic minorities reside; ④ The main factors affecting the distribution of Taoist tree species were geography and climate, but their composition was indistinguishable within each climate zone. As the climatic zone moves northward, there is no religious tree species replacement phenomenon (i.e., replacing the original religious tree species by native tree species with similar morphology or cultural meaning). The above results indicate that Taoist temples are rich in plant resources, which are potential biodiversity treasures. Thus, they play an essential role in protecting and maintaining biodiversity, with the potential to serve as a reference for regional ecological restoration and urban green space construction. Table and Figures | Reference | Related Articles | Metrics

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Research on a knowledge tracking model based on the stacked gated recurrent unit residual network Caidie HUANG, Xinping WANG, Liangyu CHEN, Yong LIU Journal of East China Normal University(Natural Science)    2022, 2022 (6): 68-78.   DOI: 10.3969/j.issn.1000-5641.2022.06.008 Abstract （426）   HTML （8）    PDF （1600KB）（270）       Knowledge map    The concept of knowledge tracking involves tracking changes in a student’s knowledge level based on historical question records and other auxiliary information, and predicting the result of a student’s subsequent answer to a question. Since the performance of existing neural network knowledge tracking models needs to be improved, this paper proposes a deep residual network based on a stacked gated recurrent unit (GRU) network named the stacked-gated recurrent unit-residual (S-GRU-R) network. The proposed solution aims to address over-fitting caused by too many parameters in a long short-term memory (LSTM) network; hence, the solution uses a GRU instead of LSTM to learn information on the sequence of questions. The use of stacked GRU can expand sequence learning capacity, and the use of residual connections can reduce the difficulty of model training. Experiments on the Statics2011 data set were completed using S-GRU-R, and AUC (area under the curve) and F1-score were used as evaluation functions. The results showed that S-GRU-R surpassed other similar recurrent neural network models in these two indicators. Table and Figures | Reference | Related Articles | Metrics

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Progress in supported Pt-based catalysts for the liquid-phase selective hydrogenation of cinnamaldehyde Mengnan LI, Huiyue XIN, Peng WU, Xiaohong LI Journal of East China Normal University(Natural Science)    2023, 2023 (1): 114-128.   DOI: 10.3969/j.issn.1000-5641.2023.01.012 Abstract （424）   HTML （21）    PDF （3712KB）（268）       Knowledge map    The selective hydrogenation of cinnamaldehyde is an important model reaction for investigating the relationship between catalyst structures and regioselectivity. In recent years, researchers have designed and synthesized a series of better-performing, supported Pt-based catalysts for the selective hydrogenation of cinnamaldehyde, based on electronic, synergistic, and geometric effects to improve the selectivity. In this mini-review, we aim to summarize the recent progress in different supported Pt-based catalysts for the selective hydrogenation of cinnamaldehyde and discuss the performance of these supported catalysts to provide ideas for the design of novel better-performing Pt-based catalysts. Table and Figures | Reference | Related Articles | Metrics

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Catalytic asymmetric synthesis of chiral heterocyclic compounds with CO2 as the C1 synthon Zhipeng ZHAO, Ying SUN, Xiaotong GAO, Feng ZHOU Journal of East China Normal University(Natural Science)    2023, 2023 (1): 31-40.   DOI: 10.3969/j.issn.1000-5641.2023.01.004 Abstract （423）   HTML （14）    PDF （1463KB）（511）       Knowledge map    As the main component of greenhouse gases, CO2 represents an inexpensive and readily available renewable C1 synthon. In the past few decades, great efforts have been made toward the development of chemical processes that use CO2 as a promising fossil fuel alternative for C1 feedstocks for the production of industrially attractive chemicals. This could provide access to materials of commercial interest from an abundant, nontoxic, renewable, and low-cost carbon source, thus offering interesting opportunities for the chemical industry, organic synthesis, and so on. Considering the importance of chiral heterocycles in organic synthesis and drug development, the development of highly stereoselective and efficient catalytic asymmetric reactions using CO2 as a C1 synthon for these chiral heterocycles has received considerable attention. Successful examples for chiral lactones, carbonates, and carbamates have already been demonstrated. In this paper, we summarize the recent advances in this field. Table and Figures | Reference | Related Articles | Metrics

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Study on sediment stability between vegetation and bare flats in a muddy intertidal flat: A case study for Chongming Dongtan in the Yangtze River Estuary Yingxin ZHANG, Wenxiang ZHANG, Benwei SHI, Yaping WANG Journal of East China Normal University(Natural Science)    2022, 2022 (6): 169-177.   DOI: 10.3969/j.issn.1000-5641.2023.03.017 Abstract （407）   HTML （24）    PDF （3028KB）（250）       Knowledge map    With the present global warming scenario, the erosion of intertidal flats in estuarine zones often occurs due to rising sea levels and an increase in human activities. Intertidal flats have an important ecological function and economic value, including for carbon sequestration, preventing flooding, water purification, attenuating waves, and tourism development. Hence, it is of great theoretical and practical significance to study the stability of the wetland ecosystem for intertidal flats. Previous studies mainly focused on the stability of intertidal bare flats, while the stability of salt marsh ecosystems has attracted relatively less attention. The mechanisms of their respective influencing factors are, as of yet, poorly understood. In this study, we took a typical muddy intertidal zone of Chongming Dongtan in the Yangtze River Estuary as an example and made a comparative analysis on sediment stability for both the salt marsh zone and the adjacent bare flat using in-situ sampling and laboratory tests. The results indicate that: ① Sediment stability improves with an increase of clay content in the bare flat. ② Sediment stability in the salt marsh zone is significantly higher than that in the adjacent bare flat because of the “reinforcing” effect of the root system. ③ Underground biomass determines sediment stability for the same type of vegetation. The sediment becomes more stable with an increase of the underground biomass in vegetation. The sediment stability of different vegetation is determined by characteristics of the vegetation root system. The sediment stability of Spartina alterniflora vegetation zone with coarser roots was worse than that of Scirpus mariqueter with finer roots. Our results not only advance theoretical research on sediment stability in intertidal flats, but also provide scientific guidance for the construction of Green Sea Defence and other coastal green protection measures. Table and Figures | Reference | Related Articles | Metrics