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29 pages, 556 KiB  
Article
Quantifying the Performance of European Agriculture Through the New European Sustainability Model
by Puiu-Lucian Georgescu, Nicoleta Barbuta-Misu, Monica Laura Zlati, Costinela Fortea and Valentin Marian Antohi
Agriculture 2025, 15(2), 210; https://doi.org/10.3390/agriculture15020210 (registering DOI) - 18 Jan 2025
Abstract
The study aims to assess the performance of European sustainable agriculture through a new model of agricultural sustainability, addressing a significant gap identified in the literature: the lack of a systematic framework integrating the economic, environmental, and resource efficiency dimensions of agricultural resource [...] Read more.
The study aims to assess the performance of European sustainable agriculture through a new model of agricultural sustainability, addressing a significant gap identified in the literature: the lack of a systematic framework integrating the economic, environmental, and resource efficiency dimensions of agricultural resource use in the context of the EU Common Agricultural Policy and the Green Deal. The research develops four synthetic indicators: ISPAS (Index of Sustainable Agricultural Productivity), IREA (Index of Reduced Emissions from Agriculture), ISAC (Index of Combined Agricultural Sustainability), and IESA (Index of Agricultural Land Area Efficiency), each reflecting complementary aspects of sustainable agricultural performance. The methodology is based on an econometric linear model and a dynamic Arellano–Bond model, which allows the analysis of the temporal relationships between synthetic indicators and agricultural sustainability performance, capturing the inertia effects and structural dynamics of the European agricultural sector. The modeling provides a robust approach to capture the interdependencies between agricultural emission reductions, sustainability mainstreaming, and land use efficiency. The results of the study indicate a superior quality of measurement by applying this integrated framework, highlighting significant relationships between emission reductions, the integration of economic and environmental dimensions, and the optimization of agricultural land use. The analysis also provides valuable policy implications, suggesting concrete directions for adapting European agricultural policies to the structural particularities of Member States. By integrating a dynamic methodological framework and innovative synthetic indicators, this study contributes to a thorough understanding of agricultural sustainability performance and provides a practical tool for underpinning sustainable agricultural policies in the European Union. Full article
(This article belongs to the Section Agricultural Economics, Policies and Rural Management)
13 pages, 12824 KiB  
Article
Detection of Crop Damage in Maize Using Red–Green–Blue Imagery and LiDAR Data Acquired Using an Unmanned Aerial Vehicle
by Barbara Dobosz, Dariusz Gozdowski, Jerzy Koronczok, Jan Žukovskis and Elżbieta Wójcik-Gront
Agronomy 2025, 15(1), 238; https://doi.org/10.3390/agronomy15010238 (registering DOI) - 18 Jan 2025
Abstract
Crop damage caused by wild animals, particularly wild boars (Sus scrofa), significantly impacts agricultural yields, especially in maize fields. This study evaluates two methods for assessing maize crop damage using UAV-acquired data: (1) a deep learning-based approach employing the Deepness plugin [...] Read more.
Crop damage caused by wild animals, particularly wild boars (Sus scrofa), significantly impacts agricultural yields, especially in maize fields. This study evaluates two methods for assessing maize crop damage using UAV-acquired data: (1) a deep learning-based approach employing the Deepness plugin in QGIS, utilizing high-resolution RGB imagery; and (2) a method based on digital surface models (DSMs) derived from LiDAR data. Manual visual assessment, supported by ground-truthing, served as the reference for validating these methods. This study was conducted in 2023 in a maize field in Central Poland, where UAV flights captured high-resolution RGB imagery and LiDAR data. Results indicated that the DSM-based method achieved higher accuracy (94.7%) and sensitivity (69.9%) compared to the deep learning method (accuracy: 92.9%, sensitivity: 35.3%), which exhibited higher precision (92.2%) and specificity (99.7%). The DSM-based method provided a closer estimation of the total damaged area (9.45% of the field) compared to the reference (10.50%), while the deep learning method underestimated damage (4.01%). Discrepancies arose from differences in how partially damaged areas were classified; the deep learning approach excluded these zones, focusing on fully damaged areas. The findings suggest that while DSM-based methods are well-suited for quantifying extensive damage, deep learning techniques detect only completely damaged crop areas. Combining these methods could enhance the accuracy and efficiency of crop damage assessments. Future studies should explore integrated approaches across diverse crop types and damage patterns to optimize wild animal damage evaluation. Full article
(This article belongs to the Special Issue Remote Sensing Applications in Crop Monitoring and Modelling)
16 pages, 466 KiB  
Article
An Evaluation and Correlation Analysis of Regional Development Under the Background of Chinese-Style Modernization
by Kaile Wang and Yunwei Chen
Sustainability 2025, 17(2), 750; https://doi.org/10.3390/su17020750 (registering DOI) - 18 Jan 2025
Abstract
Regional development represents a pivotal component in advancing the Chinese path to modernization. The pace of modernization is intrinsically linked to the effectiveness of regional development strategies. In this context, the innovative evaluation of regional development assumes critical importance. Understanding the status and [...] Read more.
Regional development represents a pivotal component in advancing the Chinese path to modernization. The pace of modernization is intrinsically linked to the effectiveness of regional development strategies. In this context, the innovative evaluation of regional development assumes critical importance. Understanding the status and dynamics of regional development offers valuable insights into the progress of Chinese-style modernization. This study, grounded in a scientific interpretation of the concept and distinctive characteristics of Chinese-style modernization, proposes an enhanced regional development evaluation indicator system within this conceptual framework. By employing dynamic comprehensive evaluation and gravitational models, this study examines the regional modernization process in China from 2012 to 2021, exploring development patterns and inter-regional relationships. The findings reveal that regional modernization has evolved into four distinct types of agglomerated areas, with a strong correlation observed between regional development patterns and geographic location. Based on these findings, targeted recommendations for optimizing regional development are provided. Full article
22 pages, 3673 KiB  
Article
Adaptive Simplified Calculation of Algal Bloom Risk Index for Reservoir-Type Drinking Water Sources Based on Improved TOPSIS and Identification of Risk Areas
by Shuyi Ji, Jihong Xia, Yue Wang, Jiayi Zu, Kejun Xu, Zewen Liu, Qihua Wang and Guofu Lin
Water 2025, 17(2), 267; https://doi.org/10.3390/w17020267 (registering DOI) - 18 Jan 2025
Abstract
As a result of global climate change and human production activities, algal blooms are occurring in aquatic environments. The problem of eutrophication in water bodies is becoming increasingly severe, affecting the safety of drinking water sources. In this study, an algal bloom risk [...] Read more.
As a result of global climate change and human production activities, algal blooms are occurring in aquatic environments. The problem of eutrophication in water bodies is becoming increasingly severe, affecting the safety of drinking water sources. In this study, an algal bloom risk index model combining the Improved Fuzzy Analytic Hierarchy Process (IFAHP), Entropy Weight Method (EWM), and Game Theory (GT) was proposed for the Shanxi Reservoir based on the TOPSIS method. After the seasonal and spatial variability in algal bloom risk from 2022 to 2023 was analyzed, an adaptive simplification of the algal bloom risk index calculation was proposed to optimize the model. To enhance its practical applicability, this study proposed an adaptive simplification of the algal bloom risk index calculation based on an improved TOPSIS approach. The error indexes R2 for the four seasons and the annual analysis were 0.9884, 0.9968, 0.9906, 0.9946, and 0.9972, respectively. Additionally, the RMSE, MAE, and MRE values were all below 0.035, indicating the method’s high accuracy. Using the adaptively simplified risk index, a risk grading and a spatial delineation of risk areas in Shanxi Reservoir were conducted. A comparison with traditional risk classification methods showed that the error in the risk levels did not exceed one grade, demonstrating the effectiveness of the proposed calculation model and risk grading approach. This study provides valuable guidance for the prevention and control of algal blooms in reservoir-type drinking water sources, contributing to the protection of drinking water sources and public health. Full article
20 pages, 10596 KiB  
Article
Finite Element Analysis of Functionally Loaded Subperiosteal Implants Evaluated on a Realistic Model Reproducing Severe Atrophic Jaws
by Gerardo Pellegrino, Maryia Karaban, Veronica Scalchi, Marco Urbani, Amerigo Giudice, Carlo Barausse and Pietro Felice
Methods Protoc. 2025, 8(1), 8; https://doi.org/10.3390/mps8010008 (registering DOI) - 18 Jan 2025
Viewed by 54
Abstract
Abstract: Implant-supported prosthetic rehabilitation for patients with severely atrophic jaws is challenging due to complex anatomical considerations and the limitations of conventional augmentation techniques. This study explores the potential of subperiosteal (juxta-osseous) implants as an alternative solution, using finite element analysis (FEA) to [...] Read more.
Abstract: Implant-supported prosthetic rehabilitation for patients with severely atrophic jaws is challenging due to complex anatomical considerations and the limitations of conventional augmentation techniques. This study explores the potential of subperiosteal (juxta-osseous) implants as an alternative solution, using finite element analysis (FEA) to evaluate mechanical performance. Realistic jaw models, developed from radiographic data, are utilized to simulate various implant configurations and load scenarios. Results indicate that different screw placements, implant designs, and structural modifications can significantly influence stress distribution and biomechanical behavior. Upper and lower jaw models were assessed under multiple load conditions to determine optimal configurations. Findings suggest that strategic adjustments, such as adding posterior screws or altering implant connections, can enhance load distribution and reduce stress concentration, particularly in critical areas. Tensile loads in critical bone areas near cortical fixing screws exceeded 50 MPa under anterior loading, while configurations with larger load distributions reduced stress on both implant and bone. The study provides evidence-based insights into optimizing subperiosteal implant design to improve stability, longevity, and patient outcomes. Full article
(This article belongs to the Section Biomedical Sciences and Physiology)
25 pages, 25562 KiB  
Article
A Mapping Method Fusing Forward-Looking Sonar and Side-Scan Sonar
by Hong Liu, Xiufen Ye, Hanwen Zhou and Hanjie Huang
J. Mar. Sci. Eng. 2025, 13(1), 166; https://doi.org/10.3390/jmse13010166 (registering DOI) - 18 Jan 2025
Viewed by 32
Abstract
In modern ocean exploration, forward-looking sonar (FLS) provides real-time 2D imaging of the seabed ahead, but its detection range is relatively limited. Conversely, side-scan sonar (SSS) enables large-scale imaging of the seabed during movement but struggles to effectively image areas directly beneath the [...] Read more.
In modern ocean exploration, forward-looking sonar (FLS) provides real-time 2D imaging of the seabed ahead, but its detection range is relatively limited. Conversely, side-scan sonar (SSS) enables large-scale imaging of the seabed during movement but struggles to effectively image areas directly beneath the sensor. Integrating FLS and SSS offers a promising solution by leveraging their complementary strengths to achieve comprehensive seabed mapping. However, no prior research has explored this fusion approach. This paper presents a novel method for FLS and SSS fusion mapping. Firstly, a novel sonar image enhancement method based on equalization is proposed, enabling simultaneous enhancement and grayscale unification of two sonar images. Additionally, an effective area extraction approach for FLS images, grounded on the approximate erosion method, is introduced to produce high-quality FLS mapping. Furthermore, by examining the data distribution in FLS and SSS mappings, the standard deviation of these datasets is utilized to refine the grayscale distribution of FLS mapping, thereby enhancing the grayscale distribution similarity between the two mapping results. Finally, FLS map data are seamlessly integrated into the gaps of the SSS map, resulting in a fused, comprehensive seabed representation. Large-scale experiments demonstrate that the proposed method effectively combines the strengths of FLS and SSS, producing complete and detailed seabed topography maps. Simultaneously, numerous ablation experiments are conducted to evaluate the impact of various parameters on fusion mapping, providing guidelines for selecting the optimal parameters. This fusion approach, thus, holds significant practical value for ocean exploration and seabed mapping applications. Full article
(This article belongs to the Section Ocean Engineering)
Show Figures

Figure 1

Figure 1
<p>Typical SSS image. The (<b>left</b>) panel depicts a rock pile, while the (<b>right</b>) panel shows a sand pattern on the seafloor.</p>
Full article ">Figure 2
<p>Typical FLS images. (<b>a</b>) The FLS imaging result of a rock pile on the seabed. (<b>b</b>) Corresponding FLS fan-shaped image. The areas circled by red lines represent the effective imaging regions of the FLS, while the remaining areas constitute the background.</p>
Full article ">Figure 3
<p>Schematic diagram of the unmanned ship carrying FLS and SSS for seabed scanning. The red lines indicate the square-cone imaging area of the FLS, while the yellow lines represent the fan-shaped imaging area of the SSS. The center line connects the centers of the FLS and SSS imaging areas and is parallel to the center lines of the FLS and SSS devices.</p>
Full article ">Figure 4
<p>Data processing flowchart of the proposed method.</p>
Full article ">Figure 5
<p>Flowchart of grayscale equalization and geocoding method for SSS. (<b>a</b>) Original SSS image. (<b>b</b>) Filtered SSS image. (<b>c</b>) Grayscale equalized SSS image. (<b>d</b>) Resulting SSS map.</p>
Full article ">Figure 6
<p>Schematic diagram of the coordinate system definition for SSS geocoding. <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msub> </mrow> </semantics></math> represents the physical center coordinates of the SSS device in WCS. <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mi>r</mi> </mrow> </msub> </mrow> </semantics></math> is the coordinate of a point on the seafloor in the WCS.</p>
Full article ">Figure 7
<p>Flowchart of grayscale equalization and geocoding method for FLS. (<b>a</b>) Original FLS image. (<b>b</b>) FLS image processed with the mean filtering method. (<b>c</b>) Binary image distinguishing the effective imaging area from the noise background, calculated using the approximate erosion method. The white area represents the effective imaging area (pixel value is 1), while the black area represents the noise background (pixel value is 0). (<b>d</b>) Grayscale-balanced image. (<b>e</b>) Effective imaging area map after grayscale equalization and removal of the noise background. (<b>f</b>) FLS mapping result after geocoding the grayscale-balanced image.</p>
Full article ">Figure 8
<p>Schematic diagram for effective region extraction based on the approximate erosion method. (<b>a</b>) illustration of the calculation process on an FLS Image. (<b>b</b>) Binary image representing the calculated effective imaging region. <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>x</mi> </mrow> <mrow> <mi>u</mi> <mi>p</mi> </mrow> </msub> </mrow> </semantics></math> keeps increasing and <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>x</mi> </mrow> <mrow> <mi>d</mi> <mi>o</mi> <mi>w</mi> <mi>n</mi> </mrow> </msub> </mrow> </semantics></math> keeps decreasing, approaching the effective imaging area in the middle step by step. <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>W</mi> </mrow> <mrow> <mi>w</mi> <mi>i</mi> <mi>d</mi> <mi>t</mi> <mi>h</mi> </mrow> </msub> </mrow> </semantics></math> is the width of FLS image. <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>H</mi> </mrow> <mrow> <mi>h</mi> <mi>e</mi> <mi>i</mi> <mi>g</mi> <mi>h</mi> <mi>t</mi> </mrow> </msub> </mrow> </semantics></math> is the height of FLS image.</p>
Full article ">Figure 9
<p>Schematic diagram of FLS imaging coordinate system. <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msub> </mrow> </semantics></math> is the coordinate of the FLS physical center in the WCS. <math display="inline"><semantics> <mrow> <msub> <mrow> <mi>P</mi> </mrow> <mrow> <mi>n</mi> </mrow> </msub> </mrow> </semantics></math> is the coordinate of a point on the seabed in the WCS. (<b>a</b>) Three-dimensional diagram. (<b>b</b>) Bottom view. (<b>c</b>) Side view.</p>
Full article ">Figure 10
<p>A schematic diagram of data sampling in the overlapping region. The blue square represents the overlapping area used to calculate the average standard deviation, corresponding to a flat seabed. The green lines represent the positions where sampling is performed within the overlapping region.</p>
Full article ">Figure 11
<p>The pixel data of the two sonar maps corresponding to the green line in <a href="#jmse-13-00166-f010" class="html-fig">Figure 10</a>. (<b>a</b>) The values of all the pixels along the line. (<b>b</b>) The statistical histogram of these data. The horizontal axis represents the original pixel values divided by 4 due to the small sample size.</p>
Full article ">Figure 12
<p>The pixel data of the two sonar maps after adjustment. (<b>a</b>) The values of all the pixels along the line. (<b>b</b>) The statistical histogram of these data. The horizontal axis represents the original pixel values divided by 4 due to the small sample size.</p>
Full article ">Figure 13
<p>The FLS and SSS maps after grayscale adjustment. (<b>a</b>) The result of directly overlaying the FLS map onto the SSS map. (<b>b</b>) The result of filling the gaps in the SSS map with the FLS map data.</p>
Full article ">Figure 14
<p>Unmanned surface vessel and equipment used to collect data.</p>
Full article ">Figure 15
<p>(<b>a</b>) ES900 side scan sonar. (<b>b</b>) M750d forward-looking sonar.</p>
Full article ">Figure 16
<p>Schematic diagram of data sampling in the overlapping region. The green lines represent the positions where single ping sampling is conducted within the overlapping region. The blue square represents the overlapping area used to calculate the average standard deviation.</p>
Full article ">Figure 17
<p>The sampling data generated by different filter parameters, <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> </mrow> </semantics></math> in Ping 1. (<b>a</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>10</mn> </mrow> </semantics></math>. (<b>b</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>50</mn> </mrow> </semantics></math>. (<b>c</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>100</mn> </mrow> </semantics></math>. (<b>d</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>200</mn> </mrow> </semantics></math>.</p>
Full article ">Figure 18
<p>Sonar maps generated by different filter parameters, <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> </mrow> </semantics></math>. (<b>a</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>10</mn> </mrow> </semantics></math>. (<b>b</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>50</mn> </mrow> </semantics></math>. (<b>c</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>100</mn> </mrow> </semantics></math>. (<b>d</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>F</mi> <mi>L</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>200</mn> </mrow> </semantics></math>.</p>
Full article ">Figure 19
<p>The sampling data generated by different filter parameters <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> </mrow> </semantics></math> in Ping 1. (<b>a</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>5</mn> </mrow> </semantics></math>. (<b>b</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>20</mn> </mrow> </semantics></math>. (<b>c</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>40</mn> </mrow> </semantics></math>. (<b>d</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>60</mn> </mrow> </semantics></math>.</p>
Full article ">Figure 20
<p>Sonar maps generated by different filter parameters, <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> </mrow> </semantics></math>. (<b>a</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>5</mn> </mrow> </semantics></math>. (<b>b</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>20</mn> </mrow> </semantics></math>. (<b>c</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>40</mn> </mrow> </semantics></math>. (<b>d</b>) <math display="inline"><semantics> <mrow> <msup> <mrow> <mi>M</mi> </mrow> <mrow> <mi>S</mi> <mi>S</mi> <mi>S</mi> </mrow> </msup> <mo>=</mo> <mn>60</mn> </mrow> </semantics></math>.</p>
Full article ">Figure 21
<p>Sonar map results generated by different parameters, <math display="inline"><semantics> <mrow> <mi>κ</mi> </mrow> </semantics></math>. (<b>a</b>) <math display="inline"><semantics> <mrow> <mi>κ</mi> <mo>=</mo> <mn>30</mn> </mrow> </semantics></math>. (<b>b</b>) <math display="inline"><semantics> <mrow> <mi>κ</mi> <mo>=</mo> <mn>40</mn> </mrow> </semantics></math>. (<b>c</b>) <math display="inline"><semantics> <mrow> <mi>κ</mi> <mo>=</mo> <mn>5</mn> </mrow> </semantics></math>0. (<b>d</b>) <math display="inline"><semantics> <mrow> <mi>κ</mi> <mo>=</mo> <mn>60</mn> </mrow> </semantics></math>.</p>
Full article ">Figure 22
<p>Comparison of large-scale fusion map and SSS map results (distance of more than 800 m). The above image represents the result of seabed mapping using SSS alone. The center images provide a zoomed-in view of a specific local area. The image below shows the seabed mapping results generated by the proposed method.</p>
Full article ">Figure 23
<p>Comparison of large-scale fusion map and SSS map results (data in Sanya, China). The above image represents the result of seabed mapping using SSS alone. The center images provide a zoomed-in view of a specific local area. The image below shows the seabed mapping results generated by the proposed method.</p>
Full article ">Figure 24
<p>Fusion maps generated using different image filtering methods. (<b>a</b>) Bilateral filtering. (<b>b</b>) Mean filtering. (<b>c</b>) Median filtering. (<b>d</b>) Gaussian filtering.</p>
Full article ">Figure 25
<p>Fusion maps generated by different fusion methods. (<b>a</b>) Fixed-weight fusion method. (<b>b</b>) This study. (<b>c</b>) Distance-weighted fusion method. (<b>d</b>) Maximum-value fusion method.</p>
Full article ">Figure 25 Cont.
<p>Fusion maps generated by different fusion methods. (<b>a</b>) Fixed-weight fusion method. (<b>b</b>) This study. (<b>c</b>) Distance-weighted fusion method. (<b>d</b>) Maximum-value fusion method.</p>
Full article ">
20 pages, 4064 KiB  
Article
Development of a Combined 2D-MGD TLC/HPTLC Method for the Separation of Terpinen-4-ol and α-Terpineol from Tea Tree, Melaleuca alternifolia, Essential Oil
by Aimé Vázquez and Nurhayat Tabanca
Biomolecules 2025, 15(1), 147; https://doi.org/10.3390/biom15010147 (registering DOI) - 18 Jan 2025
Viewed by 52
Abstract
Tea tree oil (TTO), acquired from Melaleuca alternifolia (Maiden & Betche) Cheel, Myrtaceae, is a widely utilized essential oil (EO) due to its bioactive properties. The identification and quantification of TTO ingredients is generally performed by GC-MS, which provides the most accurate results. [...] Read more.
Tea tree oil (TTO), acquired from Melaleuca alternifolia (Maiden & Betche) Cheel, Myrtaceae, is a widely utilized essential oil (EO) due to its bioactive properties. The identification and quantification of TTO ingredients is generally performed by GC-MS, which provides the most accurate results. However, in some instances, the cost and time of the analysis may pose a challenge. Thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) offer a simpler, faster, cost-effective alternative capable of simultaneously analyzing and quantifying multiple samples. In addition, for more complex oils, two-dimensional (2D) or multigradient development (MGD) TLC provide better separation. Nevertheless, further development is sometimes necessary for the isolation of comigrating components. This study showcases a combined 2D-MGD TLC/HPTLC method for the successful separation of TTO components of interest. While human error, limited separation, and the partial evaporation of volatile components may still present a challenge during the process, considerable recovery of mono- and sesquiterpenes was achieved. This protocol also resulted in the successful isolation of target oxygenated monoterpenes (OMs) producing highly pure terpinen-4-ol (100%) and α-terpineol (≥94%), confirmed by GC-MS. The accurate enantiomeric distribution of these major OMs was verified by GC-FID through the use of a chiral cyclodextrin-based stationary phase. The observed positive enantiomer range (area percent) as well as (+)/(−) ratio for each terpinen-4-ol and α-terpineol were within acceptable ISO criteria. Full article
(This article belongs to the Special Issue Feature Papers in the Natural and Bio-Derived Molecules Section)
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<p>One-dimensional HPTLC separation of TTO components using n-hexane/ethyl acetate at 8:2 (<span class="html-italic">v</span>/<span class="html-italic">v</span>). (See <a href="#biomolecules-15-00147-t001" class="html-table">Table 1</a> for track assignment.) Separation of SST before derivatization under shortwave UV light (254 nm) ((<b>A</b>) track 1). Reference standards and <span class="html-italic">Melaleuca</span> spp. EOs post derivatization under longwave UV (350 nm broadband) (<b>B</b>) and white light RT (<b>C</b>).</p>
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<p>One-dimensional HPTLC separation of TTO components using cyclohexane/ethyl acetate at 8:2 (<span class="html-italic">v</span>/<span class="html-italic">v</span>). (See <a href="#biomolecules-15-00147-t001" class="html-table">Table 1</a> for track assignment.) Separation of SST before derivatization under shortwave UV light (254 nm) ((<b>A</b>) track 1). Reference standards and <span class="html-italic">Melaleuca</span> spp. EOs post derivatization under longwave UV (350 nm broadband) (<b>B</b>) and white light RT (<b>C</b>).</p>
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<p>The one-dimensional HPTLC separation of TTO components at higher concentrations (20%) using (<b>A</b>) n-hexane/ethyl acetate at 9:1 (<span class="html-italic">v</span>/<span class="html-italic">v</span>) and (<b>B</b>) n-hexane/ethyl acetate at 8:2 (<span class="html-italic">v</span>/<span class="html-italic">v</span>). Target components are monoterpenes (a non-visible zone with approximate R<sub>F</sub> between 0.8 and 0.95); sesquiterpenes (purple zone between R<sub>F</sub> at 0.7 and 0.8); terpinen-4-ol (a wide purple zone marked by a green arrow); and α-terpineol (a narrow purple zone marked by a red arrow). A small percentage of 1,8-cineole can be observed as a narrow blue zone marked by an orange arrow.</p>
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<p>Simple 2D separation of TTO using hexane/ethyl acetate at 82:18 (<span class="html-italic">v</span>/<span class="html-italic">v</span>) in both directions. α-Terpineol, terpinen-4-ol, and 1,8-cineole are signaled by red, green, and orange arrows, respectively.</p>
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<p>2D-MGD separation of TTO using n-hexane/ethyl acetate multigradient (<a href="#biomolecules-15-00147-t003" class="html-table">Table 3</a>) observed under white (<b>A</b>) and UV366 (<b>B</b>). Color-coded arrows show increased separation of target components.</p>
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<p>The GC-FID chiral separation of terpinen-4-ol (<b>A</b>) and α-terpineol (<b>B</b>). In both cases, the enantiomeric distribution is displayed (<b>1</b>), followed by a 1:1 reference standard mix (<b>2</b>), (−) enantiomer (<b>3</b>) and (+) enantiomer (<b>4</b>). Asterisk (*) referrs to manual integration.</p>
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12 pages, 2298 KiB  
Article
PTR-ToF-MS VOC Profiling of Raw and Cooked Gilthead Sea Bream Fillet (Sparus aurata): Effect of Rearing System, Season, and Geographical Origin
by Iuliia Khomenko, Valentina Ting, Fabio Brambilla, Mirco Perbellini, Luca Cappellin and Franco Biasioli
Molecules 2025, 30(2), 402; https://doi.org/10.3390/molecules30020402 (registering DOI) - 18 Jan 2025
Viewed by 72
Abstract
This study explores the impact of geographical origin, harvest time, and cooking on the volatile organic compound (VOC) profiles of wild and reared seabream from the Adriatic and Tyrrhenian Seas. A Proton Transfer Reaction–Time of Flight–Mass Spectrometry (PTR-ToF-MS) allowed for VOC profiling with [...] Read more.
This study explores the impact of geographical origin, harvest time, and cooking on the volatile organic compound (VOC) profiles of wild and reared seabream from the Adriatic and Tyrrhenian Seas. A Proton Transfer Reaction–Time of Flight–Mass Spectrometry (PTR-ToF-MS) allowed for VOC profiling with high sensitivity and high throughput. A total of 227 mass peaks were identified. Principal component analysis (PCA) showed a clear separation between cooked and raw samples, with cooking causing a significant increase in 64% of VOCs, especially hydrogen sulphide, methanethiol, and butanal. A two-way ANOVA revealed significant effects of origin, time, and their interaction on VOC concentration, with 102 mass peaks varying significantly based on all three factors. Seasonal effects were also notable, particularly in reared fish from the Adriatic Sea, where compounds like monoterpenes and aromatics were higher during non-breeding months, likely due to environmental factors unique to that area. Differences between wild and reared fish were influenced by lipid content and seasonal changes, impacting the VOC profile of seabream. These findings provide valuable insights into how cooking, geographical origin, and seasonality interact to define the flavour profile of seabream, with potential applications in improving quality control and product differentiation in seafood production. Full article
(This article belongs to the Special Issue Innovative Analytical Techniques in Food Chemistry)
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<p>Principal component analysis (PCA) on the measured VOC concentration for raw and cooked wild sea bream that were reared in either the Adriatic, Tyrrhenian, or Levant Sea.</p>
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<p>Differences in t.i. (<b>a</b>) hydrogen sulphide (<span class="html-italic">m</span>/<span class="html-italic">z</span> 34.995) (mean ± SD), (<b>b</b>) methanethiol (<span class="html-italic">m</span>/<span class="html-italic">z</span> 49.011), (<b>c</b>) methanol, and (<b>d</b>) hexenol (<span class="html-italic">m</span>/<span class="html-italic">z</span> 83.086) between cooked and raw fish samples and the level of significance according to a two-way ANOVA of geographical origin and time of harvest.</p>
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<p>The score plot (<b>a</b>) and loading plot (<b>b</b>) of the principal component analysis (PCA) on the measured VOC concentration for cooked wild sea bream from the Levant Sea, and cooked sea bream reared in either the Adriatic or Tyrrhenian Sea. The different colours in the score plot (<b>a</b>) show the geographical origin reported in the legend, and colour shades indicate the months in which the fish were harvested. The colours of the loading plot (<b>b</b>) correspond to the classification according to the two-way ANOVA results presented, as well as those in the Venn diagram (<b>c</b>).</p>
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<p>Selected mass peaks (mean ± SD), which distinguish different fish geographical origins, are plotted for three fish types under two conditions (cooked and raw). The two selected mass peaks are tentatively identified as (<b>a</b>) an isotope of dimethyl sulphide (<span class="html-italic">m</span>/<span class="html-italic">z</span> 65.022); (<b>b</b>) 2-Methyl propanal and butanal (<span class="html-italic">m</span>/<span class="html-italic">z</span> 73.066); (<b>c</b>) hexanal (<span class="html-italic">m</span>/<span class="html-italic">z</span> 101.097); and (<b>d</b>) 1,2,4-Trimethylbenzene, 1,3,5-Trimethylbenzene, 1-Ethyl-2-methylbenzene, and Propylbenzene (<span class="html-italic">m</span>/<span class="html-italic">z</span> 121.103).</p>
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19 pages, 870 KiB  
Article
Prioritizing Patient Selection in Clinical Trials: A Machine Learning Algorithm for Dynamic Prediction of In-Hospital Mortality for ICU Admitted Patients Using Repeated Measurement Data
by Emma Pedarzani, Alberto Fogangolo, Ileana Baldi, Paola Berchialla, Ilaria Panzini, Mohd Rashid Khan, Giorgia Valpiani, Savino Spadaro, Dario Gregori and Danila Azzolina
J. Clin. Med. 2025, 14(2), 612; https://doi.org/10.3390/jcm14020612 (registering DOI) - 18 Jan 2025
Viewed by 96
Abstract
Background: A machine learning prognostic mortality scoring system was developed to address challenges in patient selection for clinical trials within the Intensive Care Unit (ICU) environment. The algorithm incorporates Red blood cell Distribution Width (RDW) data and other demographic characteristics to predict ICU [...] Read more.
Background: A machine learning prognostic mortality scoring system was developed to address challenges in patient selection for clinical trials within the Intensive Care Unit (ICU) environment. The algorithm incorporates Red blood cell Distribution Width (RDW) data and other demographic characteristics to predict ICU mortality alongside existing ICU mortality scoring systems like Simplified Acute Physiology Score (SAPS). Methods: The developed algorithm, defined as a Mixed-effects logistic Random Forest for binary data (MixRFb), integrates a Random Forest (RF) classification with a mixed-effects model for binary outcomes, accounting for repeated measurement data. Performance comparisons were conducted with RF and the proposed MixRFb algorithms based solely on SAPS scoring, with additional evaluation using a descriptive receiver operating characteristic curve incorporating RDW’s predictive mortality ability. Results: MixRFb, incorporating RDW and other covariates, outperforms the SAPS-based variant, achieving an area under the curve of 0.882 compared to 0.814. Age and RDW were identified as the most significant predictors of ICU mortality, as reported by the variable importance plot analysis. Conclusions: The MixRFb algorithm demonstrates superior efficacy in predicting in-hospital mortality and identifies age and RDW as primary predictors. Implementation of this algorithm could facilitate patient selection for clinical trials, thereby improving trial outcomes and strengthening ethical standards. Future research should focus on enriching algorithm robustness, expanding its applicability across diverse clinical settings and patient demographics, and integrating additional predictive markers to improve patient selection capabilities. Full article
(This article belongs to the Section Intensive Care)
19 pages, 7245 KiB  
Article
Integrating Drone Truthing and Functional Classification of Remote Sensing Time Series for Supervised Vegetation Mapping
by Giacomo Quattrini, Simone Pesaresi, Nicole Hofmann, Adriano Mancini and Simona Casavecchia
Remote Sens. 2025, 17(2), 330; https://doi.org/10.3390/rs17020330 (registering DOI) - 18 Jan 2025
Viewed by 127
Abstract
Accurate vegetation mapping is essential for monitoring biodiversity and managing habitats, particularly in the context of increasing environmental pressures and conservation needs. Ground truthing plays a crucial role in ensuring the accuracy of supervised remote sensing maps, as it provides the high-quality reference [...] Read more.
Accurate vegetation mapping is essential for monitoring biodiversity and managing habitats, particularly in the context of increasing environmental pressures and conservation needs. Ground truthing plays a crucial role in ensuring the accuracy of supervised remote sensing maps, as it provides the high-quality reference data needed for model training and validation. However, traditional ground truthing methods are labor-intensive, time-consuming and restricted in spatial coverage, posing challenges for large-scale or complex landscapes. The advent of drone technology offers an efficient and cost-effective solution to these limitations, enabling the rapid collection of high-resolution imagery even in remote or inaccessible areas. This study proposes an approach to enhance the efficiency of supervised vegetation mapping in complex landscapes, integrating Multivariate Functional Principal Component Analysis (MFPCA) applied to the Sentinel-2 time series with drone-based ground truthing. Unlike traditional ground truthing activities, drone truthing enabled the generation of large, spatially balanced reference datasets, which are critical for machine learning classification systems. These datasets improved classification accuracy by ensuring a comprehensive representation of vegetation spectral variability, enabling the classifier to identify the key phenological patterns that best characterize and distinguish different vegetation types across the landscape. The proposed methodology achieves a classification accuracy of 92.59%, significantly exceeding the commonly reported thresholds for habitat mapping. This approach, characterized by its efficiency, repeatability and adaptability, aligns seamlessly with key environmental monitoring and conservation policies, such as the Habitats Directive. By integrating advanced remote sensing with drone-based technologies, it offers a scalable and cost-effective solution to the challenges of biodiversity monitoring, enabling timely updates and supporting effective habitat management in diverse and complex environments. Full article
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<p>Supervised pipeline to derive plant associations and habitat maps from Sentinel-2 time series using Multivariate Functional Principal Component Analysis and drone truthing activities.</p>
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<p>Study area: (<b>a</b>) overview of the study area on a regional scale. (<b>b</b>) Reference data overlaid on the Digital Elevation Model, marking the boundaries of the Gola del Furlo State Nature Reserve (in black), the Special Protection Area (SPA) “Furlo” (code: IT5310029) (in blue) and the Special Area of Conservation (SAC) “Gola del Furlo” (IT5310016) (in red). (<b>c</b>) Entry points to the Furlo Gorge, with Mount Paganuccio to the left and Mount Pietralata to the right.</p>
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<p>Drone photo acquisition at each survey point. Initially, an overhead photo (<b>a</b>) is captured from high above the canopy. This is followed by a close-range shot (<b>b</b>), providing a detailed view. Here, <span class="html-italic">Ostrya carpinifolia</span> is prominently visible. At this lower altitude, photos are taken in the four cardinal directions (north, east, south, and west) for species abundance estimation. Both photos were captured on 6 July 2022.</p>
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<p>Graphical representation of the main findings from the Functional Data Analysis applied to the multispectral weekly time series of the Furlo area. (<b>a</b>) Seasonal profiles for all of the pixels in the study area, with the columns representing the nine Sentinel-2 bands analyzed. (<b>b</b>) The first three MFPCA components. The influence of these components on the overall means of the nine selected time series (depicted by the black line) is shown by adding (red line) or subtracting (blue line) a multiple (e.g., the median of the scores) of each principal functional component. (<b>c</b>) MFPCA ordination space based on the top three MFPCA components, enabling comparisons between vegetation types. The spider diagram illustrates the relationship between MFPC components and vegetation types, with the labels corresponding to <a href="#remotesensing-17-00330-t001" class="html-table">Table 1</a>.</p>
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<p>Seasonal temporal profiles of the target classes across various spectral bands correspond to the 1118 reference data points. The bold red line represents the mean vegetation band variation. The red polygon shows the 10th–90th percentile range. The black line represents the mean vegetation band variation for the entire study area. The row acronyms denote the plant associations and habitats listed in <a href="#remotesensing-17-00330-t001" class="html-table">Table 1</a>, while the columns refer to the different Sentinel-2 bands.</p>
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<p>Vegetation and habitats map of study area: the map was obtained by the supervised random forest classification of the main seasonal remotely sensed phenological variations, as well as the main topographic predictors. The legend acronyms correspond to the plant associations and habitats listed in <a href="#remotesensing-17-00330-t001" class="html-table">Table 1</a>. The boundaries of the Gola del Furlo State Nature Reserve are outlined in black, that of the Special Protection Area (SPA) “Furlo” (code: IT5310029) are outlined in blue, and that of the Special Area of Conservation (SAC) “Gola del Furlo” (IT5310016) are outlined in red.</p>
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<p>Forested area, photographed on 7 October 2022, which was challenging to survey with traditional methods due to its inaccessibility and complex topography, which would have required considerable time.</p>
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<p>Proportion of variance explained by the identified functional components (eigenvalues). The bar plot shows the proportion of variance explained by each principal component, with the cumulative variance illustrated by the red line. The first three components individually explain 48.55%, 26.79%, and 10.17% of the variance, respectively, accounting for a combined total of 85.51% of the variance. Collectively, the first 10 components account for 97.40% of the total variance.</p>
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19 pages, 456 KiB  
Article
Mathematical Models for Coverage with Star Tree Backbone Topology for 5G Millimeter Waves Networks
by Sergio Cordero, Pablo Adasme, Ali Dehghan Firoozabadi, Renata Lopes Rosa and Demóstenes Zegarra Rodríguez
Symmetry 2025, 17(1), 141; https://doi.org/10.3390/sym17010141 (registering DOI) - 18 Jan 2025
Viewed by 123
Abstract
This paper proposes mathematical optimization models for solving the network planning problem using millimeter wave technology for 5G wireless communications networks. To this end, it is assumed that a set of users, M={1,,m}, and [...] Read more.
This paper proposes mathematical optimization models for solving the network planning problem using millimeter wave technology for 5G wireless communications networks. To this end, it is assumed that a set of users, M={1,,m}, and a set of base stations, N={1,,n}, are deployed randomly in a square area. In particular, the base stations should be connected, forming a star backbone so that users can connect to their nearest active base stations forming the backbone where the connections are symmetric. In particular, the first two models maximize the number of users connected to the backbone and minimize the distance costs of connecting users to the base stations, and distances of connecting the base stations themselves. Similarly, the last two models maximize and minimize the same objectives and the number of base stations to be activated to form the star backbone. Each user is allowed to connect to a unique active base station. In general, the millimeter wave technology presents a high path loss. Consequently, the transmission distances should be no larger than 300 m at most for different radial transmissions. Thus, a direct line of sight between users and base stations is assumed. Finally, we propose local search-based algorithms that allow finding near-optimal solutions for all our tested instances. Our numerical results indicate that we can solve network instances optimally with up to k=100, n=200, and m=5000 users. Full article
(This article belongs to the Section Engineering and Materials)
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<p>Star network topology configuration composed of ten nodes and 30 users. The black node is the sink server base station, while the blue ones are the leaf base stations of the star. The green nodes represent users. Blue edges connect the star solution and the green links connect users to the base stations within the radial transmission area. The radial distance is 300 ms and all users are covered.</p>
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<p>A larger star network topology configuration composed of 50 nodes (BSs) and 1000 users. The black node is the sink server base station, while the blue ones are the leaf ones of the star. The green nodes and edges represent users connected to leaf BSs. The radial distance is 300 ms and all users are covered by the star.</p>
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<p>Objective values, CPU time in seconds, attended users, and gaps obtained for each instance in <a href="#symmetry-17-00141-t001" class="html-table">Table 1</a> where the radial transmission distance is 150 ms.</p>
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<p>Objective values, CPU time in seconds, attended users, and gaps obtained for each instance in <a href="#symmetry-17-00141-t002" class="html-table">Table 2</a> where the radial transmission distance is 200 ms.</p>
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<p>Objective values, CPU time in seconds, attended users, and gaps obtained for each instance in <a href="#symmetry-17-00141-t003" class="html-table">Table 3</a> where the radial transmission distance is 300 ms.</p>
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<p>Objective values, CPU time in seconds, attended users, number of base stations, and gaps obtained for each instance in <a href="#symmetry-17-00141-t004" class="html-table">Table 4</a> where the radial transmission distance is 150 ms.</p>
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<p>Objective values, CPU time in seconds, attended users, number of base stations, and gaps obtained for each instance in <a href="#symmetry-17-00141-t005" class="html-table">Table 5</a> where the radial transmission distance is 200 ms.</p>
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<p>Objective values, CPU time in seconds, attended users, number of base stations, and gaps obtained for each instance in <a href="#symmetry-17-00141-t006" class="html-table">Table 6</a> where the radial transmission distance is 300 ms.</p>
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23 pages, 74396 KiB  
Article
Change of NDVI in the Upper Reaches of the Yangtze River and Its Influence on the Water–Sand Process in the Three Gorges Reservoir
by Yiming Ma, Mingyue Li, Huaming Yao, Peng Chen and Hongzhong Pan
Sustainability 2025, 17(2), 739; https://doi.org/10.3390/su17020739 (registering DOI) - 18 Jan 2025
Viewed by 137
Abstract
Vegetation coverage in the upper reaches of the Yangtze River is very important to the ecological balance in this area, and it also has an impact on the inflow runoff and sediment transport processes of the Three Gorges Reservoir. Based on the normalized [...] Read more.
Vegetation coverage in the upper reaches of the Yangtze River is very important to the ecological balance in this area, and it also has an impact on the inflow runoff and sediment transport processes of the Three Gorges Reservoir. Based on the normalized vegetation index data (NDVI) with 250 m resolution in the upper reaches of the Yangtze River, annual runoff, sediment transport, land use, meteorology, and other data—and by using the methods of Sen + Mann–Kendall trend analysis, partial correlation analysis, and Hurst index—this paper analyzes the temporal and spatial variation characteristics, driving factors, and the influence on the water and sediment inflow processes of the Three Gorges Reservoir in each sub-basin in the upper reaches of the Yangtze River. The results show that (1) NDVI in the upper Yangtze River showed a fluctuating upward trend from 2001 to 2022, and the overall vegetation cover continued to increase, showing a spatial pattern of low in the west and high in the east. At the same time, the runoff volume of the upper reaches of the Yangtze River did not show a significant upward trend from 2006 to 2022, while the sand transport decreased significantly; (2) Among the NDVI-influencing factors in the upper reaches of the Yangtze River, the area driven by the land use factor accounts for about 43% of the whole study area, followed by precipitation; (3) Precipitation significantly affected runoff, and NDVI was negatively correlated with sand transport in most of the watersheds, suggesting that improved vegetation could help reduce sediment loss. In addition, the future trend of vegetation change was predicted to be dominated by improvement (Hurst > 0.5) based on the Hurst index, which will provide a reference for the NDVI change in the upper Yangtze River and the prediction of sediment inflow to the Three Gorges Reservoir. Full article
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<p>Schematic diagram of the location, scope, and terrain of the research area.</p>
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<p>Annual variation of NDVI in various basins in the upper reaches of the Yangtze River from 2001 to 2022.</p>
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<p>Spatial distribution of NDVI in the Upper Yangtze River Basin from 2001 to 2022.</p>
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<p>Significance of spatial variation in NDVI in the Upper Yangtze River Basin from 2001 to 2022.</p>
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<p>Spatial fluctuation of annual NDVI in the Upper Yangtze River Basin from 2001 to 2022.</p>
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<p>Interannual variability of runoff (<b>a</b>) and sand transport (<b>b</b>) in the Yangtze River Basin. Error bars indicate percentage of data for each year (5%).</p>
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<p>Spatial distribution of NDVI and precipitation correlation coefficients (<b>a</b>) and correlation coefficients significance (<b>b</b>) in the upper Yangtze River Basin from 2001 to 2022.</p>
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<p>Distribution of land cover types in the Upper Yangtze River Basin in 2001, 2010, and 2022.</p>
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<p>Vegetation change for different land cover types in the upper Yangtze River Basin from 2001 to 2022.</p>
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<p>Spatial distribution of partial correlation coefficient (<b>A</b>–<b>C</b>) and partial correlation significance (<b>D</b>–<b>F</b>) between NDVI and climate factors in the upper Yangtze River Basin from 2000 to 2022.</p>
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<p>Spatial distribution of dominant climate factors for NDVI changes in the upper Yangtze River Basin from 2001 to 2022.</p>
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<p>Persistence of NDVI in the Upper Yangtze River Basin from 2001 to 2022.</p>
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<p>Future trends of NDVI changes in the upper reaches of the Yangtze River.</p>
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15 pages, 5662 KiB  
Article
A Facile Electrode Modification Approach Based on Metal-Free Carbonaceous Carbon Black/Carbon Nanofibers for Electrochemical Sensing of Bisphenol A in Food
by Jin Wang, Zhen Yang, Shuanghuan Gu, Mingfei Pan and Longhua Xu
Foods 2025, 14(2), 314; https://doi.org/10.3390/foods14020314 (registering DOI) - 18 Jan 2025
Viewed by 120
Abstract
Bisphenol A (BPA) is a typical environmental estrogen that is distributed worldwide and has the potential to pose a hazard to the ecological environment and human health. The development of an efficient and sensitive sensing strategy for the monitoring of BPA residues is [...] Read more.
Bisphenol A (BPA) is a typical environmental estrogen that is distributed worldwide and has the potential to pose a hazard to the ecological environment and human health. The development of an efficient and sensitive sensing strategy for the monitoring of BPA residues is of paramount importance. A novel electrochemical sensor based on carbon black and carbon nanofibers composite (CB/f-CNF)-assisted signal amplification has been successfully constructed for the amperometric detection of BPA in foods. Herein, the hybrid CB/f-CNF was prepared using a simple one-step ultrasonication method, and exhibited good electron transfer capability and excellent catalytic properties, which can be attributed to the large surface area of carbon black and the strong enhancement of the conductivity and porosity of carbon nanofibers, which promote a faster electron transfer process on the electrode surface. Under the optimized conditions, the proposed CB/f-CNF/GCE sensor exhibited a wide linear response range (0.4–50.0 × 10−6 mol/L) with a low limit of detection of 5.9 × 10−8 mol/L for BPA quantification. Recovery tests were conducted on canned peaches and boxed milk, yielding satisfactory recoveries of 86.0–102.6%. Furthermore, the developed method was employed for the rapid and sensitive detection of BPA in canned meat and packaged milk, demonstrating comparable accuracy to the HPLC method. This work presents an efficient signal amplification strategy through the utilization of carbon/carbon nanocomposite sensitization technology. Full article
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<p>Schematic illustration of the construction of the CB/f-CNF/GCE sensor. Note: Black line, red line, blue line, purple line, yellow line, green line and cyan line are the DPV curves of CB/f-CNF/GCE in bisphenol A solution of 0.4 μM, 1 μM, 2 μM, 6 μM, 10 μM, 20 μM and 50 μM, respectively.</p>
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<p>SEM images of CNF (<b>A</b>), f-CNF (<b>B</b>), CB (<b>C</b>), and CB/f-CNF (<b>D</b>). XRD patterns for the as-synthesized CB, f-CNF, and CB/f-CNF (<b>E</b>); Raman spectra of carbon black, f-CNF, and CB/f-CNF composite (<b>F</b>).</p>
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<p>The CV (<b>A</b>) and EIS (<b>B</b>) in a [Fe(CN)6]<sup>3−/4−</sup> redox probe solution response of GCE, CB/GCE, f-CNF/GCE, and CB/f-CNF/GCE. CV responses for GCE (<b>C</b>) and (<b>D</b>) The CB/f-CNF/GCE was analyzed at different scan rates, ranging from 10 to 100 mV s<sup>−1</sup>, in a 2.0 mmol·L<sup>−1</sup> [Fe(CN)6]<sup>3/4−</sup> solution. Note: Different lines from top to bottom are the CV curves of GCE and CB/f-CNF/GCE under the sweep speed of 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 mv respectively.</p>
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<p>(<b>A</b>) CV curves of bare GCE, CB/GCE, f-CNF/GCE and CB/f-CNF/GCE in the BR containing 50 μmol L<sup>−1</sup> BPA and CV curves of CB/f-CNF/GCE in a BPA-free BR solution (blank). (<b>B</b>) CV curves of CB/f-CNF/GCE in the BR containing 20 μmol L<sup>−1</sup> BPA at various scan rates: 20, 40, 60, 80, and 100 mV s<sup>−1</sup>. (<b>C</b>) The linear relationship of the BPA oxidation peak currents versus the scan rates. (<b>D</b>) The relationship between the BPA oxidation peak potentials and the natural logarithm of scan rates. Note: The black, red, blue, green and purple lines are the CV curves of CB/f-CNF/GCE in BR containing 20 μmol L<sup>−1</sup> BPA at: 20, 40, 60, 80 and 100 mV s<sup>−1</sup> scanning rates, respectively.</p>
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<p>(<b>A</b>) DPV curves of CB/f-CNF/GCE for different concentrations of BPA. (<b>B</b>) The linear relationship between the peak current and the concentration of BPA was studied, along with anti-interference performance (<b>C</b>) and (<b>D</b>) repeatability experiments of CB/f-CNF/GCE. Note: In the <a href="#foods-14-00314-f005" class="html-fig">Figure 5</a>A, the DPV curves of CB/f-CNF/GCE in bisphenol A solution of 0.4 μM, 1 μM, 2 μM, 6 μM, 10 μM, 20 μM and 50 μM are shown in black lines, red lines, blue lines, purple lines, yellow lines, green lines and cyan lines respectively.</p>
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44 pages, 24354 KiB  
Article
Estimating Subcanopy Solar Radiation Using Point Clouds and GIS-Based Solar Radiation Models
by Daniela Buchalová, Jaroslav Hofierka, Jozef Šupinský and Ján Kaňuk
Remote Sens. 2025, 17(2), 328; https://doi.org/10.3390/rs17020328 (registering DOI) - 18 Jan 2025
Viewed by 153
Abstract
This study explores advanced methodologies for estimating subcanopy solar radiation using LiDAR (Light Detection and Ranging)-derived point clouds and GIS (Geographic Information System)-based models, with a focus on evaluating the impact of different LiDAR data types on model performance. The research compares the [...] Read more.
This study explores advanced methodologies for estimating subcanopy solar radiation using LiDAR (Light Detection and Ranging)-derived point clouds and GIS (Geographic Information System)-based models, with a focus on evaluating the impact of different LiDAR data types on model performance. The research compares the performance of two modeling approaches—r.sun and the Point Cloud Solar Radiation Tool (PCSRT)—in capturing solar radiation dynamics beneath tree canopies. The models were applied to two contrasting environments: a forested area and a built-up area. The r.sun model, based on raster data, and the PCSRT model, which uses voxelized point clouds, were evaluated for their accuracy and efficiency in simulating solar radiation. Data were collected using terrestrial laser scanning (TLS), unmanned laser scanning (ULS), and aerial laser scanning (ALS) to capture the structural complexity of canopies. Results indicate that the choice of LiDAR data significantly affects model outputs. PCSRT, with its voxel-based approach, provides higher precision in heterogeneous forest environments. Among the LiDAR types, ULS data provided the most accurate solar radiation estimates, closely matching in situ pyranometer measurements, due to its high-resolution coverage of canopy structures. TLS offered detailed local data but was limited in spatial extent, while ALS, despite its broader coverage, showed lower precision due to insufficient point density under dense canopies. These findings underscore the importance of selecting appropriate LiDAR data for modeling solar radiation, particularly in complex environments. Full article
(This article belongs to the Section Remote Sensing for Geospatial Science)
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<p>Locations of study areas. (<b>A</b>): Forested area; (<b>B</b>): built-up area; (<b>C</b>): side view of the forested area; (<b>D</b>): side view of the built-up area—Jesenná Street. Green lines indicate canopy areas.</p>
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<p>Data collection methods used in the study areas; TLS (terrestrial laser scanning), ALS (aerial laser scanning), ULS (unmanned laser scanning).</p>
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<p>TLS positions in (<b>A</b>): forested area; (<b>B</b>): built-up area.</p>
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<p>The TLS point cloud density in the forested area; (<b>A</b>): total points (vegetation and ground), (<b>B</b>): ground points.</p>
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<p>The TLS point cloud density in the built-up area; (<b>A</b>): total points (vegetation and ground), (<b>B</b>): ground points.</p>
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<p>The ULS point cloud density in the forested area; (<b>A</b>): total points (vegetation and ground), (<b>B</b>): ground points.</p>
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<p>The ALS point cloud density in the forested area; (<b>A</b>): total points (vegetation and ground), (<b>B</b>): ground points.</p>
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<p>The ALS point cloud density in the built-up area; (<b>A</b>): total points, (<b>B</b>): ground points.</p>
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<p>Localization of pyranometers in the forested area; (<b>A</b>): detailed photo of pyranometer in location A, (<b>B</b>): detailed photo of pyranometer in location B, (<b>C</b>): detailed photo of pyranometer in location C, (<b>D</b>): detailed photo of pyranometer in location D.</p>
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<p>Localization of pyranometer in the built-up area; (<b>A</b>): detailed photo of pyranometer in location A.</p>
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<p>Selected polygons for detailed data analysis in the forested area. P1: High vegetation; P2: meadow; P3: low vegetation; P4: high vegetation with canopy gaps.</p>
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<p>Comparison of TLS, ALS, and ULS data from the top and side views of polygon 1, 10 × 10 m, high vegetation.</p>
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<p>Comparison of TLS, ALS, and ULS data from the top and side views of polygon 2, 10 × 10 m, meadow.</p>
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<p>Comparison of TLS, ALS, and ULS data from the top and side views of polygon 3, 10 × 10 m, low vegetation.</p>
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<p>Comparison of TLS, ALS, and ULS data from the top and side views of polygon 4, 10 × 10 m, high vegetation with a gap in the vegetation.</p>
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<p>Selected polygons for detailed data analysis—built-up area. P1: high vegetation; P2: roof; P3: parking lot; P4: high vegetation.</p>
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<p>Comparison of TLS and ALS data from the top and side views of polygon 1, 10 × 10 m, high vegetation.</p>
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<p>Comparison of TLS and ALS data from the top and side views of polygon 2, 10 × 10 m, roof.</p>
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<p>Comparison of TLS and ALS data from the top and side views of polygon 3, 10 × 10 m, parking.</p>
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<p>Comparison of TLS and ALS data from the top and side views of polygon 4, 10 × 10 m, high vegetation.</p>
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<p>Estimated subcanopy solar radiation by PCSRT in forested area—ALS data; 27 September 2023, 12 a.m.</p>
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<p>Estimated subcanopy solar radiation by PCSRT in forested area—ULS data; 27 September 2023, 12 a.m.</p>
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<p>Estimated subcanopy solar radiation by PCSRT in forested area—TLS data; 27 September 2023, 12 a.m.</p>
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<p>Estimated subcanopy solar radiation by r.sun—ULS data; 27 September 2023, 10 a.m.; white line—computing region for LPI.</p>
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<p>Estimated subcanopy solar radiation by r.sun—ALS data; 27 September 2023, 10 a.m.; white line—computing region for LPI.</p>
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<p>Estimated subcanopy solar radiation by r.sun—TLS data; 27 September 2023, 10 a.m.; white line—computing region for LPI.</p>
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<p>Estimated subcanopy solar radiation by PCSRT in built-up area—ALS data; 27 September 2023, 12 a.m.</p>
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<p>Estimated subcanopy solar radiation by PCSRT in built-up area—TLS data; 27 September 2023, 12 a.m.</p>
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<p>Estimated subcanopy solar radiation by r.sun—ALS data; 28 September 2023, 10 a.m.; white line—computing region for LPI.</p>
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<p>Estimated subcanopy solar radiation by r.sun—TLS data; 28 September 2023, 10 a.m.; white line—computing region for LPI.</p>
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<p>Solar irradiance difference maps between r.sun and PCSRT models using the TLS and ALS data, built-up area; (<b>A</b>): difference between r.sun TLS—r.sun ALS, (<b>B</b>): difference between PCSRT TLS—PCSRT ALS, (<b>C</b>): difference between r.sun TLS—PCSRT TLS, (<b>D</b>): difference between r.sun ALS—PCSRT ALS.</p>
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<p>Solar irradiance difference maps between r.sun and PCSRT models—ULS, ALS, and TLS data, forested area; (<b>A</b>): difference between r.sun ULS—r.sun ALS, (<b>B</b>): difference between r.sun ULS—r.sun TLS, (<b>C</b>): difference between r.sun TLS—r.sun ALS, (<b>D</b>): difference between PCSRT ULS—PCSRT ALS, (<b>E</b>): PCSRT ULS—PCSRT TLS, (<b>F</b>): PCSRT TLS—PCSRT ALS, (<b>G</b>): r.sun ULS—PCSRT ULS, (<b>H</b>): r.sun TLS—PCSRT TLS, (<b>I</b>): r.sun ALS—PCSRT ALS.</p>
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<p>Solar irradiance difference histograms between r.sun and PCSRT models using the TLS and ALS data, built-up area; (<b>A</b>): difference between r.sun TLS—r.sun ALS, (<b>B</b>): difference between PCSRT TLS—PCSRT ALS, (<b>C</b>): difference between r.sun TLS—PCSRT TLS, (<b>D</b>): difference between r.sun ALS—PCSRT ALS.</p>
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<p>Solar irradiance histograms between r.sun and PCSRT models—ULS, ALS, and TLS data, forested area; (<b>A</b>): difference between r.sun ULS—r.sun ALS, (<b>B</b>): difference between r.sun ULS—r.sun TLS, (<b>C</b>): difference between r.sun TLS—r.sun ALS, (<b>D</b>): difference between PCSRT ULS—PCSRT ALS, (<b>E</b>): PCSRT ULS—PCSRT TLS, (<b>F</b>): PCSRT TLS—PCSRT ALS, (<b>G</b>): r.sun ULS—PCSRT ULS, (<b>H</b>): r.sun TLS—PCSRT TLS, (<b>I</b>): r.sun ALS—PCSRT ALS..</p>
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19 pages, 10970 KiB  
Article
Variations in Sedimentation Rate and Corresponding Adjustments of Longitudinal Gradient in the Cascade Reservoirs of the Lower Jinsha River
by Suiji Wang
Water 2025, 17(2), 262; https://doi.org/10.3390/w17020262 (registering DOI) - 18 Jan 2025
Viewed by 155
Abstract
The Xiangjiaba and Xiluodu reservoirs, as important components of the large cascade reservoirs in the lower Jinsha River, and the interactive changes in sediment trapping amounts, the differences in sedimentation dynamics, and the potential mutual influence mechanisms among them are scientific issues worthy [...] Read more.
The Xiangjiaba and Xiluodu reservoirs, as important components of the large cascade reservoirs in the lower Jinsha River, and the interactive changes in sediment trapping amounts, the differences in sedimentation dynamics, and the potential mutual influence mechanisms among them are scientific issues worthy of attention. Based on the multiple observed data of thalweg elevation before and after the completion of the dam construction, this study calculated the average sedimentation rates of all 20 km segments of the above-mentioned reservoirs in different periods. Meanwhile, the local mean gradients between adjacent segments and the regional mean gradients from the segments to the dam in the corresponding periods were calculated. The results show that the maximum and average sedimentation rates of the Xiangjiaba Reservoir, which was built earliest and is located downstream, were as high as 19.62 m yr−1 and 8.88 m yr−1, respectively, in the first half year after the dam closure. After the completion of the Xiluodu Reservoir, an adjacent cascade reservoir upstream, the average sedimentation rate of the Xiangjiaba Reservoir in the following seven years dropped to 0.67 m yr−1. The maximum and average sedimentation rates of the Xiluodu Reservoir were 9.07 m yr−1 and 4.15 m yr−1, respectively, within one year after the dam closure, and its average sedimentation rate in the following six years was 2.51 m yr−1. The spatial variations of sedimentation rates in these two reservoirs follow different changing patterns. There is an obvious correlation between the change in mean gradient and the change in sedimentation rate. The sequence of dam construction, the relative positions of the reservoirs, the differences in sediment trapping amounts, and operation modes are the key factors controlling the changes in sedimentation rate and gradient in the reservoir area. This study reveals the interactive changes in sedimentation rates among cascade reservoirs and the response mechanism of river channel morphology, and has a guiding role for the formulation of effective measures for the sustainable utilization of cascade reservoirs. Full article
(This article belongs to the Special Issue Regional Geomorphological Characteristics and Sedimentary Processes)
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<p>Locations of cascade reservoirs/dams, main tributaries, and typical cross-sections in the lower Jinsha River (WDD, BHT, XLD, and XJB represent Wudongde, Baihetan, Xiluodu, and Xiangjiaba dams/reservoirs, while TZL, PZH, and SDZ refer to the hydrological stations of Sanduizi, Panzhihua, and Tongzilin, respectively).</p>
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<p>Spatiotemporal variations in the average erosion and deposition depth and average sedimentation rate along channel thalweg line in the Xiangjiaba Reservoir.</p>
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<p>Spatiotemporal variations in average scouring and sedimentation thickness and average sedimentation rate along channel thalweg line in the Xiluodu Reservoir.</p>
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<p>Changes in the thalweg elevation and gradient before and after the dam completion in the Xiangjiaba Reservoir.</p>
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<p>Changes in the thalweg elevation and gradient before and after the dam completion in the Xiluodu Reservoir.</p>
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<p>Comparison of typical cross-sectional morphological characteristics in cascade reservoir sections.</p>
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<p>Changes in width–depth ratio of typical cross-sections in cascade reservoirs.</p>
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<p>Characteristics of thalweg gradient between adjacent typical cross-sections in cascade reservoirs.</p>
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