Gijsman, R., Horstman, E.M., Swales, A., MacDonald, I.T., Bouma, T.J., Wal, D., Wijnberg, K.M. (2024) Mangrove forest drag and bed stabilisation effects on intertidal flat morphology. Earth Surface Processes and Landforms, 49(3), 1117–1134, https://doi.org/10.1002/esp.5758
In the Data Availability Statement of the ‘Open Research’ section, the authors missed the opportunity to mention that the hydrodynamic data that were specifically used for the calibration of the drag coefficients were obtained by the University of Waikato. The calibration of the drag coefficients is presented in Section S2 of the ‘Supporting Information’. For that reason, the authors would like to add the following sentence to the Data Availability Statement: ‘The hydrodynamic data that are used for the calibration of the drag coefficients are available from the University of Waikato upon reasonable request’.
Accordingly, in the ‘Acknowledgements’, the authors would like to adjust the sentence ‘Pressure, profile and vegetation data was partly obtained in prior field campaigns funded by the Royal Society of New Zealand's Marsden Fund (grant 14-UOW-011)’ to ‘Pressure, profile and vegetation data were partly obtained in prior field campaigns by EMH, Karin Bryan and Julia Mullarney (University of Waikato), funded by the Royal Society of New Zealand's Marsden Fund (grant 14-UOW-011)’.
The authors apologize for this inaccuracy.
Gijsman, R., Horstman, E.M., Swales, A., MacDonald, I.T., Bouma, T.J., Wal, D., Wijnberg, K.M. (2024) Mangrove forest drag and bed stabilisation effects on intertidal flat morphology.Earth Surface Processes and Landforms, 49(3), 1117-1134, https://doi.org/10.1002/esp.5758In 在 "开放研究 "部分的 "数据可用性声明 "中，作者没有提及专门用于校准阻力系数的水动力数据是由怀卡托大学获得的。阻力系数的校准情况见 "辅助信息 "的 S2 部分。因此，作者希望在 "数据可用性声明 "中添加以下句子："用于校准阻力系数的流体力学数据可向怀卡托大学合理索取"。因此，在 "致谢 "中，作者希望将 "压力、剖面和植被数据部分是在新西兰皇家学会马斯登基金（14-UOW-011 号赠款）资助的先前实地考察中获得的 "这句话调整为 "压力、剖面和植被数据部分是在新西兰皇家学会马斯登基金（14-UOW-011 号赠款）资助的先前实地考察中获得的，由 EMH、Karin Bryan 和 Julia Mullarney（怀卡托大学）提供"。
{"title":"Correction to ‘Mangrove forest drag and bed stabilisation effects on intertidal flat morphology’","authors":"","doi":"10.1002/esp.5971","DOIUrl":"10.1002/esp.5971","url":null,"abstract":"<p>\u0000 <span>Gijsman, R.</span>, <span>Horstman, E.M.</span>, <span>Swales, A.</span>, <span>MacDonald, I.T.</span>, <span>Bouma, T.J.</span>, <span>Wal, D.</span>, <span>Wijnberg, K.M.</span> (<span>2024</span>) <span>Mangrove forest drag and bed stabilisation effects on intertidal flat morphology</span>. <i>Earth Surface Processes and Landforms</i>, <span>49</span>(<span>3</span>), <span>1117</span>–<span>1134</span>, https://doi.org/10.1002/esp.5758</p><p>In the Data Availability Statement of the ‘Open Research’ section, the authors missed the opportunity to mention that the hydrodynamic data that were specifically used for the calibration of the drag coefficients were obtained by the University of Waikato. The calibration of the drag coefficients is presented in Section S2 of the ‘Supporting Information’. For that reason, the authors would like to add the following sentence to the Data Availability Statement: ‘The hydrodynamic data that are used for the calibration of the drag coefficients are available from the University of Waikato upon reasonable request’.</p><p>Accordingly, in the ‘Acknowledgements’, the authors would like to adjust the sentence ‘Pressure, profile and vegetation data was partly obtained in prior field campaigns funded by the Royal Society of New Zealand's Marsden Fund (grant 14-UOW-011)’ to ‘Pressure, profile and vegetation data were partly obtained in prior field campaigns by EMH, Karin Bryan and Julia Mullarney (University of Waikato), funded by the Royal Society of New Zealand's Marsden Fund (grant 14-UOW-011)’.</p><p>The authors apologize for this inaccuracy.</p>","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/esp.5971","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Soil loss is a common land degradation process worldwide, which is impacted by land use and climate change. In this study, random forests (RF) were first used to establish a soil loss model at the scale of a small watershed in the hilly‐gully region of the Loess Plateau based on the field observation data. Subsequently, the model was used to predict soil loss in the Chabagou watershed under the historical (1990–2020) and future emission scenarios, namely SSP1–2.6 (low‐emission), SSP2–4.5 (medium‐emission) and SSP5–8.5 (high‐emission) (2030–2,100) from the Coupled Model Intercomparison Project Phases 6 (CMIP6). In the RF model, the coefficient of determination (R2) and Nash‐Sutcliffe coefficient of efficiency (NS) were both greater than 0.86, and the RMSE‐observations standard deviation ratio (RSR) was less than 0.36. Additionally, the RF‐based model had higher simulation accuracy and robustness than those of the previous soil loss models, indicating its potential for wider applications in simulating soil loss. Compared with soil loss between 1990 and 1999, climate change led to a 35.36% increase in soil loss, while land use change resulted in an 11.13% reduction from 2000 to 2020 in the Chabagou watershed. This reveals that the current land use management could not effectively counterbalance the soil loss caused by rainstorms. Furthermore, compared with the historical period (1990–2020), under SSP1–2.6, SSP2–4.5 and SSP5–8.5 (2030–2,100), the soil loss rates without land use change would be increased by 6.01%, 19.11% and 35.35%, while the soil loss rates with land use change would be changed by −5.88%, +4.41% and +19.12%, respectively. These results help to provide a scientific basis for enhancing the capacity to respond to climate change and mitigation of soil and water loss on the Loess Plateau.
{"title":"Predicting soil loss in small watersheds under different emission scenarios from CMIP6 using random forests","authors":"Yulan Chen, Nan Wang, Juying Jiao, Jianjun Li, Leichao Bai, Yue Liang, Yanhong Wei, Ziqi Zhang, Qian Xu, Zhixin Zhang, Jiaxi Wang","doi":"10.1002/esp.5980","DOIUrl":"https://doi.org/10.1002/esp.5980","url":null,"abstract":"Soil loss is a common land degradation process worldwide, which is impacted by land use and climate change. In this study, random forests (RF) were first used to establish a soil loss model at the scale of a small watershed in the hilly‐gully region of the Loess Plateau based on the field observation data. Subsequently, the model was used to predict soil loss in the Chabagou watershed under the historical (1990–2020) and future emission scenarios, namely SSP1–2.6 (low‐emission), SSP2–4.5 (medium‐emission) and SSP5–8.5 (high‐emission) (2030–2,100) from the Coupled Model Intercomparison Project Phases 6 (CMIP6). In the RF model, the coefficient of determination (R<jats:sup>2</jats:sup>) and Nash‐Sutcliffe coefficient of efficiency (NS) were both greater than 0.86, and the RMSE‐observations standard deviation ratio (RSR) was less than 0.36. Additionally, the RF‐based model had higher simulation accuracy and robustness than those of the previous soil loss models, indicating its potential for wider applications in simulating soil loss. Compared with soil loss between 1990 and 1999, climate change led to a 35.36% increase in soil loss, while land use change resulted in an 11.13% reduction from 2000 to 2020 in the Chabagou watershed. This reveals that the current land use management could not effectively counterbalance the soil loss caused by rainstorms. Furthermore, compared with the historical period (1990–2020), under SSP1–2.6, SSP2–4.5 and SSP5–8.5 (2030–2,100), the soil loss rates without land use change would be increased by 6.01%, 19.11% and 35.35%, while the soil loss rates with land use change would be changed by −5.88%, +4.41% and +19.12%, respectively. These results help to provide a scientific basis for enhancing the capacity to respond to climate change and mitigation of soil and water loss on the Loess Plateau.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Shuttle Radar Topography Mission (SRTM) is a digital representation of the terrain surface morphology that contains rich terrain information and is widely used in environmental analyses. However, SRTM is adversely affected by mixed noise, which typically include random and stripe noise. Mixed noise results in the significant loss of topographic information, which reduce the validity of related research. To eliminate mixed noise in SRTM data, we propose an adaptive low‐rank group sparse model based on edge preservation (ALGS_EP) to remove mixed noise from datasets. The method relies on a low‐rank group sparse model that considers the gradient features of the terrain. It calculates a terrain factor to adapt the noise elimination model to terrain changes. Additionally, it integrates with the edge structure of elevation data and applies a double‐gradient constraint to preserve the structural details of the elevation data. The proposed model, built upon the alternating direction multiplier method framework, enhances the traditional weighted kernel paradigm minimization algorithm by introducing variable weights that adjust according to the gradient of elevation data during iterations. Additionally, it incorporates the correlation between strip noise and residual data blocks when computing the iteration count, ensuring an iterative solution approach that converges to the optimal solution. We used ALGS_EP to process global SRTM 1 data and published a higher‐quality and higher‐precision elevation dataset. The elevation data noise before and after noise elimination were statistically analyzed. Simulated and empirical results show that the model is highly robust and more effective than existing methods in both visual and quantitative evaluations. The noise elimination rate was 97.6%, compared to the original data. Therefore, this research was valuable for applications that use digital elevation model as an important data layer.
{"title":"An adaptive low‐rank group sparse model based on edge‐preserving for eliminating mixed noise in SRTM","authors":"Xiao Fan, Hongming Zhang, Qinke Yang, Baoyuan Liu, Chenyu Ge, Zhuang Yan, Yuwei Sun, Jincheng Ni, Linlin Yuan, Xiaoxing Huang","doi":"10.1002/esp.5976","DOIUrl":"https://doi.org/10.1002/esp.5976","url":null,"abstract":"The Shuttle Radar Topography Mission (SRTM) is a digital representation of the terrain surface morphology that contains rich terrain information and is widely used in environmental analyses. However, SRTM is adversely affected by mixed noise, which typically include random and stripe noise. Mixed noise results in the significant loss of topographic information, which reduce the validity of related research. To eliminate mixed noise in SRTM data, we propose an adaptive low‐rank group sparse model based on edge preservation (ALGS_EP) to remove mixed noise from datasets. The method relies on a low‐rank group sparse model that considers the gradient features of the terrain. It calculates a terrain factor to adapt the noise elimination model to terrain changes. Additionally, it integrates with the edge structure of elevation data and applies a double‐gradient constraint to preserve the structural details of the elevation data. The proposed model, built upon the alternating direction multiplier method framework, enhances the traditional weighted kernel paradigm minimization algorithm by introducing variable weights that adjust according to the gradient of elevation data during iterations. Additionally, it incorporates the correlation between strip noise and residual data blocks when computing the iteration count, ensuring an iterative solution approach that converges to the optimal solution. We used ALGS_EP to process global SRTM 1 data and published a higher‐quality and higher‐precision elevation dataset. The elevation data noise before and after noise elimination were statistically analyzed. Simulated and empirical results show that the model is highly robust and more effective than existing methods in both visual and quantitative evaluations. The noise elimination rate was 97.6%, compared to the original data. Therefore, this research was valuable for applications that use digital elevation model as an important data layer.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ana Entrena, Luis F. Auqué, María J. Gimeno, Joan J. Fornós
Phreatic overgrowths on speleothems (POS) are unique precipitates that are found in a small number of coastal caves around the world, like those in the Mallorca Island. Their growth is directly related to the water level of the brackish lakes connected to the sea characteristic of these caves and, therefore, they can be very reliable indicators of past sea levels. The study presented here characterizes and classifies an important number of POS samples collected in the coastal caves of Mallorca. The characterization includes not only the observations made on 117 handheld samples and on 102 thin sections from POS, but also the study of their mineralogy and their location in the caves. This study has provided the basis for a systematization of all these characteristics, some of which are reported here for the first time in POS samples. The results indicate that (1) most of the POS precipitate on stalactites, (2) calcite POS show branched internal and external texture and their most common crystal fabric is mosaic calcite and (3) aragonite POS show globular external texture and fan‐shaped internal texture, and their principal crystal fabric is needle‐like. All the aragonitic samples have been found above or at the same heights as the current sea level, which indicates that they have probably formed during warmer climates. The calcite POS have been found at heights above and below the present sea level and are interpreted as to have formed during cold and rainy periods. The systematization proposed in this paper could be applied and checked in other POS worldwide. Additionally, the combination of these results with the information obtained from studies on the present precipitation of these phreatic speleothems in some Mallorca caves has provided an insight on their formation conditions which will enlarge the utility of these speleothems as palaeoenvironmental indicators.
{"title":"Phreatic overgrowths on speleothems (POS) from the Mallorca caves: Morphology, mineralogy, and crystal fabric classification","authors":"Ana Entrena, Luis F. Auqué, María J. Gimeno, Joan J. Fornós","doi":"10.1002/esp.5967","DOIUrl":"https://doi.org/10.1002/esp.5967","url":null,"abstract":"Phreatic overgrowths on speleothems (POS) are unique precipitates that are found in a small number of coastal caves around the world, like those in the Mallorca Island. Their growth is directly related to the water level of the brackish lakes connected to the sea characteristic of these caves and, therefore, they can be very reliable indicators of past sea levels. The study presented here characterizes and classifies an important number of POS samples collected in the coastal caves of Mallorca. The characterization includes not only the observations made on 117 handheld samples and on 102 thin sections from POS, but also the study of their mineralogy and their location in the caves. This study has provided the basis for a systematization of all these characteristics, some of which are reported here for the first time in POS samples. The results indicate that (1) most of the POS precipitate on stalactites, (2) calcite POS show branched internal and external texture and their most common crystal fabric is mosaic calcite and (3) aragonite POS show globular external texture and fan‐shaped internal texture, and their principal crystal fabric is needle‐like. All the aragonitic samples have been found above or at the same heights as the current sea level, which indicates that they have probably formed during warmer climates. The calcite POS have been found at heights above and below the present sea level and are interpreted as to have formed during cold and rainy periods. The systematization proposed in this paper could be applied and checked in other POS worldwide. Additionally, the combination of these results with the information obtained from studies on the present precipitation of these phreatic speleothems in some Mallorca caves has provided an insight on their formation conditions which will enlarge the utility of these speleothems as palaeoenvironmental indicators.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142225602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bruno Martins, Catarina Pinheiro, Adélia Nunes, António Bento‐Gonçalves, Manuela Laranjeira
Mediterranean forests are very degraded, mainly due to the intensification of wildfires in recent decades, which, boosted by human activity, have contributed to the acceleration of erosion processes and soil degradation. Under certain conditions, this also contributes to the formation of gullies. The aim of this study is to identify and characterise gullies considering their morphological and topographical aspects and determine the factors that control vegetation regrowth in gullies in a Mediterranean environment after a wildfire. The gullies were identified based on the 2018 orthophotograph, after the large wildfire of October 2017 that affected the entire study area. To analyse the vegetation regrowth, we used the normalised difference vegetation index (NDVI) derived from seven Landsat 8 OLI/TIRS images (2017–2022). The Spearman's rho correlation coefficient was selected to estimate the correlation between gully characteristics and vegetation regrowth. Before running the model, a multicollinearity test was conducted (VIF ≤ 10 and tolerance ≥ 0.1). Stepwise multiple regression was conducted in order to identify the independent variable that has a strong relationship with vegetation regrowth. A marginal effects plot was drawn up. The 38 gullies identified are in forest areas, mainly composed of pine (Pinus pinaster) trees (17 gullies) or a combination of pine trees and broadleaf (Eucalyptus globulus) trees (eight gullies). In all, invasive species are present in 11 gullies, alone (one gully), together with pine trees (four gullies) or with other species (six). The other gully has broadleaf trees. The vegetation in the gully channel recovered well in the year after the wildfire. In the following years there was growth at a slower rate until it reached similar values of NDVI in 2022, 5 years after the wildfire. Stepwise multiple regression (SMR) produced a solution with three models. The three derived dimensions covered 66.8% of the variance, considering the mean width, altitude and flow accumulation. The results can help to devise more effective management strategies for areas where the recurrence and intensity of wildfires have contributed very effectively to soil loss and degradation from gully erosion, with a view to a more resilient and sustainable territory.
{"title":"Site‐scale drivers of post‐fire vegetation regrowth in gullies: A case study in Mediterranean Europe","authors":"Bruno Martins, Catarina Pinheiro, Adélia Nunes, António Bento‐Gonçalves, Manuela Laranjeira","doi":"10.1002/esp.5974","DOIUrl":"https://doi.org/10.1002/esp.5974","url":null,"abstract":"Mediterranean forests are very degraded, mainly due to the intensification of wildfires in recent decades, which, boosted by human activity, have contributed to the acceleration of erosion processes and soil degradation. Under certain conditions, this also contributes to the formation of gullies. The aim of this study is to identify and characterise gullies considering their morphological and topographical aspects and determine the factors that control vegetation regrowth in gullies in a Mediterranean environment after a wildfire. The gullies were identified based on the 2018 orthophotograph, after the large wildfire of October 2017 that affected the entire study area. To analyse the vegetation regrowth, we used the normalised difference vegetation index (NDVI) derived from seven Landsat 8 OLI/TIRS images (2017–2022). The Spearman's rho correlation coefficient was selected to estimate the correlation between gully characteristics and vegetation regrowth. Before running the model, a multicollinearity test was conducted (<jats:italic>VIF</jats:italic> ≤ 10 and tolerance ≥ 0.1). Stepwise multiple regression was conducted in order to identify the independent variable that has a strong relationship with vegetation regrowth. A marginal effects plot was drawn up. The 38 gullies identified are in forest areas, mainly composed of pine (<jats:styled-content style=\"fixed-case\"><jats:italic>Pinus pinaster</jats:italic></jats:styled-content>) trees (17 gullies) or a combination of pine trees and broadleaf (<jats:styled-content style=\"fixed-case\"><jats:italic>Eucalyptus globulus</jats:italic></jats:styled-content>) trees (eight gullies). In all, invasive species are present in 11 gullies, alone (one gully), together with pine trees (four gullies) or with other species (six). The other gully has broadleaf trees. The vegetation in the gully channel recovered well in the year after the wildfire. In the following years there was growth at a slower rate until it reached similar values of NDVI in 2022, 5 years after the wildfire. Stepwise multiple regression (SMR) produced a solution with three models. The three derived dimensions covered 66.8% of the variance, considering the mean width, altitude and flow accumulation. The results can help to devise more effective management strategies for areas where the recurrence and intensity of wildfires have contributed very effectively to soil loss and degradation from gully erosion, with a view to a more resilient and sustainable territory.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Brianna Shepherd, Eric W. Portenga, Alexys J. Peplinski
Schmidt hammer R‐values, which reflect the degree of rock surface weathering, can be paired with independent rock surface exposure ages to produce Schmidt hammer exposure‐age dating (SHD) calibration curves that are used to provide rapid estimations of exposure ages for undated rock surfaces. In this Letter, we lay the groundwork for later establishing a SHD calibration curve based on glacial erratics deposited by the Laurentide Ice Sheet in the North American Great Lakes region. First, we establish a reference R‐value for a calibration boulder, which may be used to facilitate direct comparison of R‐values collected by different individuals using mechanical N‐type Schmidt hammers, specifically. We then assess how no, light or heavy use of a carborundum puck to smooth rock surfaces affects resulting R‐value data. Lastly, we compare two different R‐value metrics on the same rock surface: Rmean (n = 30) versus ΔR (Rmax − Rmin of five consecutive R‐values on the same spot). In all assessments, Rmean is similar for erratic surfaces with no and light surface treatment, and both are significantly lower than Rmean of surfaces with heavy treatment. Thus, we advise against the use of heavy surface treatment in SHD applications. We observe no relationship between inferred erratic age and either Rmean or ΔR, which could arise from inferred ages of erratics being inaccurate, from inferred ages of erratics being too similar or from measuring too few erratics from each landform.
反映岩石表面风化程度的施密特锤 R 值可与独立的岩石表面暴露年龄配对，生成施密特锤暴露年龄定年（SHD）校准曲线，用于快速估算未定年岩石表面的暴露年龄。在这封信中，我们为以后根据北美五大湖区劳伦泰德冰盖沉积的冰川岩屑建立 Schmidt hammer 暴露年代校准曲线奠定了基础。首先，我们为校准巨石建立了一个参考 R 值，该值可用于直接比较不同个人使用 N 型施密特机械锤收集的 R 值。然后，我们评估了不使用、轻度使用或重度使用碳化硅球来平滑岩石表面对所得 R 值数据的影响。最后，我们对同一岩石表面的两种不同 R 值指标进行了比较：Rmean（n = 30）与 ΔR（同一地点五个连续 R 值的 Rmax - Rmin）。在所有评估中，未进行表面处理和轻度表面处理的不稳定表面的 Rmean 值相似，都明显低于重度表面处理的 Rmean 值。因此，我们建议在 SHD 应用中不要使用重度表面处理。我们观察到，推断的飘忽不定的年龄与 Rmean 或 ΔR 之间没有关系，这可能是由于推断的飘忽不定的年龄不准确、推断的飘忽不定的年龄过于相似或测量的每种地貌的飘忽不定的数量太少。
{"title":"Quantifying the effects of carborundum rock surface smoothing for Schmidt hammer R‐value metrics measured on glacial erratics in the North American Great Lakes region","authors":"Brianna Shepherd, Eric W. Portenga, Alexys J. Peplinski","doi":"10.1002/esp.5973","DOIUrl":"https://doi.org/10.1002/esp.5973","url":null,"abstract":"Schmidt hammer R‐values, which reflect the degree of rock surface weathering, can be paired with independent rock surface exposure ages to produce Schmidt hammer exposure‐age dating (SHD) calibration curves that are used to provide rapid estimations of exposure ages for undated rock surfaces. In this Letter, we lay the groundwork for later establishing a SHD calibration curve based on glacial erratics deposited by the Laurentide Ice Sheet in the North American Great Lakes region. First, we establish a reference R‐value for a calibration boulder, which may be used to facilitate direct comparison of R‐values collected by different individuals using mechanical N‐type Schmidt hammers, specifically. We then assess how no, light or heavy use of a carborundum puck to smooth rock surfaces affects resulting R‐value data. Lastly, we compare two different R‐value metrics on the same rock surface: R<jats:sub>mean</jats:sub> (<jats:italic>n</jats:italic> = 30) versus ΔR (R<jats:sub>max</jats:sub> − R<jats:sub>min</jats:sub> of five consecutive R‐values on the same spot). In all assessments, R<jats:sub>mean</jats:sub> is similar for erratic surfaces with no and light surface treatment, and both are significantly lower than R<jats:sub>mean</jats:sub> of surfaces with heavy treatment. Thus, we advise against the use of heavy surface treatment in SHD applications. We observe no relationship between inferred erratic age and either R<jats:sub>mean</jats:sub> or ΔR, which could arise from inferred ages of erratics being inaccurate, from inferred ages of erratics being too similar or from measuring too few erratics from each landform.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lingxiao Wang, Chenqi Huang, Lin Zhao, Huayun Zhou, Shibo Liu, Yunqi Tang, Zhibin Li, Yao Xiao, Defu Zou, Guangyue Liu, Erji Du, Guojie Hu, Chong Wang
The landscape and landforms in permafrost regions are transforming due to climate change and permafrost thaw. This study uses optical and radar remote sensing, alongside spatial analysis, to examine thermokarst features and their driving factors in the source region of the Yangtze River (SRYR) on the central Tibetan Plateau. We analyse the distribution, interaction, and key environmental factors influencing thermokarst ponds and ground surface deformation, which are the two widespread and noticeable thermokarst features. Since the 1960s, the number of small water bodies has doubled from approximately ~2 × 104 to ~4 × 104 by the 2020s, with the median size of these water bodies decreasing from 2.3 × 104 m2 to 1.4 × 104 m2. The permafrost terrain has an average subsidence rate of 6.8 mm/a. About 50.9% of the SRYR exhibits evident thermokarst features. Surficial geological factors, especially geomorphology and slope, are primary factors in shaping the spatial distributions of thermokarst features. Both seasonal deformation and long‐term subsidence rates are more pronounced in areas with thermokarst ponds. However, once pond coverage exceeds around 5%, the amplifying effect on long‐term subsidence rates and seasonal deformation diminishes. The investigation further reveals that the relationship between seasonal deformation and long‐term subsidence is not strictly linear and that the combined increase in seasonal deformation and long‐term subsidence applies only to areas with seasonal deformation below approximately 20 mm. Beyond this threshold, the long‐term subsidence rate is no longer exacerbated by increased seasonal deformation.
{"title":"Permafrost thaw and thermokarst in the source region of the Yangtze river in the central Tibetan plateau revealed by radar and optical remote sensing","authors":"Lingxiao Wang, Chenqi Huang, Lin Zhao, Huayun Zhou, Shibo Liu, Yunqi Tang, Zhibin Li, Yao Xiao, Defu Zou, Guangyue Liu, Erji Du, Guojie Hu, Chong Wang","doi":"10.1002/esp.5969","DOIUrl":"https://doi.org/10.1002/esp.5969","url":null,"abstract":"The landscape and landforms in permafrost regions are transforming due to climate change and permafrost thaw. This study uses optical and radar remote sensing, alongside spatial analysis, to examine thermokarst features and their driving factors in the source region of the Yangtze River (SRYR) on the central Tibetan Plateau. We analyse the distribution, interaction, and key environmental factors influencing thermokarst ponds and ground surface deformation, which are the two widespread and noticeable thermokarst features. Since the 1960s, the number of small water bodies has doubled from approximately ~2 × 10<jats:sup>4</jats:sup> to ~4 × 10<jats:sup>4</jats:sup> by the 2020s, with the median size of these water bodies decreasing from 2.3 × 10<jats:sup>4</jats:sup> m<jats:sup>2</jats:sup> to 1.4 × 10<jats:sup>4</jats:sup> m<jats:sup>2</jats:sup>. The permafrost terrain has an average subsidence rate of 6.8 mm/a. About 50.9% of the SRYR exhibits evident thermokarst features. Surficial geological factors, especially geomorphology and slope, are primary factors in shaping the spatial distributions of thermokarst features. Both seasonal deformation and long‐term subsidence rates are more pronounced in areas with thermokarst ponds. However, once pond coverage exceeds around 5%, the amplifying effect on long‐term subsidence rates and seasonal deformation diminishes. The investigation further reveals that the relationship between seasonal deformation and long‐term subsidence is not strictly linear and that the combined increase in seasonal deformation and long‐term subsidence applies only to areas with seasonal deformation below approximately 20 mm. Beyond this threshold, the long‐term subsidence rate is no longer exacerbated by increased seasonal deformation.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kai Boggild, Michael Z. Li, Jordan B. R. Eamer, Cooper D. Stacey
Movement of sediment along shallow continental shelves is a natural process with wide‐ranging environmental and economic implications, making it of high importance to marine spatial planning efforts in the offshore. Development of marine renewable energy, for instance, requires detailed understanding of the morphodynamics of mobile bedforms to select foundation types and ensure safe installation of infrastructure in shallow shelf environments. This study evaluates geomorphology and sediment mobility of Dogfish Bank (< 20 mbsl) in the Hecate Strait offshore British Columbia, Canada, using hydroacoustic and airborne bathymetric data combined with seismic profiles and grain‐size information. These data reveal current‐swept features ranging from sediment‐depleted lag to sediment‐abundant sand ridges and dunes, with sand ribbons and furrows in‐between. Seismic reflection data show up to 15 m of surficial sand concentrated beneath north‐aligned sand ridges that dominate the bathymetry of northwest Hecate Strait. Sand ribbons (typically understood sediment‐limited features in shallow marine environments) are notably maintained over seabed with comparable sand thickness to adjacent dunes (i.e. sediment‐abundant features), suggesting local spatial variability in hydrodynamics and sediment characteristics (principally grain size) influence expression of mobile bedforms. Repeat mapping between 2008 and 2019 shows dunes and ribbons both migrate northwards, with largest seafloor changes along northeast‐facing lee sides of dunes, matching closely with published models of sediment mobility which suggest northward bedform migration is largely driven by storms. Median total migration distance is 164 m (northward) for dunes (time‐averaged rate of 14.9 m/year). Sand ribbons show less migration (median northward distance of 73 m) and migrate in a depth‐dependent manner. Because sand ribbons are typically flow‐parallel features, their lateral migration likely results from varying current directions and flow acceleration over shallower seabed. Sand ribbon migration should therefore a consideration in studies examining seabed change, particularly when they are formed over unconsolidated sediment.
{"title":"Geomorphology and sediment mobility on sand banks: A study of Dogfish Bank, Hecate Strait, Northeast Pacific Ocean","authors":"Kai Boggild, Michael Z. Li, Jordan B. R. Eamer, Cooper D. Stacey","doi":"10.1002/esp.5925","DOIUrl":"https://doi.org/10.1002/esp.5925","url":null,"abstract":"Movement of sediment along shallow continental shelves is a natural process with wide‐ranging environmental and economic implications, making it of high importance to marine spatial planning efforts in the offshore. Development of marine renewable energy, for instance, requires detailed understanding of the morphodynamics of mobile bedforms to select foundation types and ensure safe installation of infrastructure in shallow shelf environments. This study evaluates geomorphology and sediment mobility of Dogfish Bank (< 20 mbsl) in the Hecate Strait offshore British Columbia, Canada, using hydroacoustic and airborne bathymetric data combined with seismic profiles and grain‐size information. These data reveal current‐swept features ranging from sediment‐depleted lag to sediment‐abundant sand ridges and dunes, with sand ribbons and furrows in‐between. Seismic reflection data show up to 15 m of surficial sand concentrated beneath north‐aligned sand ridges that dominate the bathymetry of northwest Hecate Strait. Sand ribbons (typically understood sediment‐limited features in shallow marine environments) are notably maintained over seabed with comparable sand thickness to adjacent dunes (i.e. sediment‐abundant features), suggesting local spatial variability in hydrodynamics and sediment characteristics (principally grain size) influence expression of mobile bedforms. Repeat mapping between 2008 and 2019 shows dunes and ribbons both migrate northwards, with largest seafloor changes along northeast‐facing lee sides of dunes, matching closely with published models of sediment mobility which suggest northward bedform migration is largely driven by storms. Median total migration distance is 164 m (northward) for dunes (time‐averaged rate of 14.9 m/year). Sand ribbons show less migration (median northward distance of 73 m) and migrate in a depth‐dependent manner. Because sand ribbons are typically flow‐parallel features, their lateral migration likely results from varying current directions and flow acceleration over shallower seabed. Sand ribbon migration should therefore a consideration in studies examining seabed change, particularly when they are formed over unconsolidated sediment.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arnab Das, Renji Remesan, Somsubhra Chakraborty, Adrian L. Collins, Ashok Kumar Gupta
The need to control soil erosion has received increasing attention, but quantitative data on the sources of suspended sediment in many river–reservoir systems is still lacking. The goal of this research was to compare the application of spectroscopic [mid‐infrared (MIR)] and mineralogical [X‐ray diffraction (XRD)] fingerprints for assessing relative sediment source contributions from different land use groups (agricultural lands, forests and human settlements) in the Konar–Damodar river–reservoir system in India. Source apportionment was estimated using partial least square (PLS) regression for spectroscopic tracers (MIR) and the Bayesian MixSIAR model for mineralogical tracers. Both methods identified differences between the pre‐ and post‐monsoon sediment contributions of forests (overall contribution bounds of ~35–43%). During monsoon seasons, both fingerprinting methods indicated agricultural land use as the primary source of suspended sediment. Although there were some temporal variations in the predicted contributions of the land use sources, the MIR‐PLS and mineralogical–MixSIAR methods produced comparable ranges. The respective variations in contributions, using MIR‐PLS and mineralogical–MixSIAR, were ~31 to 66% compared with ~36 to 61% for agricultural lands, ~21 to 43% compared with ~15 to 39% for forests and ~16 to 37% compared with ~19 to 32% for human settlements.
{"title":"Comparative study using spectroscopic and mineralogical fingerprinting for suspended sediment source apportionment in a river–reservoir system","authors":"Arnab Das, Renji Remesan, Somsubhra Chakraborty, Adrian L. Collins, Ashok Kumar Gupta","doi":"10.1002/esp.5972","DOIUrl":"https://doi.org/10.1002/esp.5972","url":null,"abstract":"The need to control soil erosion has received increasing attention, but quantitative data on the sources of suspended sediment in many river–reservoir systems is still lacking. The goal of this research was to compare the application of spectroscopic [mid‐infrared (MIR)] and mineralogical [X‐ray diffraction (XRD)] fingerprints for assessing relative sediment source contributions from different land use groups (agricultural lands, forests and human settlements) in the Konar–Damodar river–reservoir system in India. Source apportionment was estimated using partial least square (PLS) regression for spectroscopic tracers (MIR) and the Bayesian MixSIAR model for mineralogical tracers. Both methods identified differences between the pre‐ and post‐monsoon sediment contributions of forests (overall contribution bounds of ~35–43%). During monsoon seasons, both fingerprinting methods indicated agricultural land use as the primary source of suspended sediment. Although there were some temporal variations in the predicted contributions of the land use sources, the MIR‐PLS and mineralogical–MixSIAR methods produced comparable ranges. The respective variations in contributions, using MIR‐PLS and mineralogical–MixSIAR, were ~31 to 66% compared with ~36 to 61% for agricultural lands, ~21 to 43% compared with ~15 to 39% for forests and ~16 to 37% compared with ~19 to 32% for human settlements.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hai Xiao, Junkui Guo, Zhenyao Xia, Ping Guo, Feng Gao, Rui Xiang, Deyu Liu, Yu Ding, Di Wang, Lun Zhang
The particle size distribution (PSD) of eroded sediment can effectively reflect changes in erosion processes. Hedgerows provide significant soil and water conservation benefits and influence erosion processes. However, the impact of hedgerows on the PSD of eroded sediment remains unclear. Therefore, three slope conditions (control check, CK; only hedgerow root, R; and whole hedgerow, P) involving the configuration of two slope gradients (15 and 25°) were established, and simulated rainfall experiments were conducted under three rainfall intensities (60, 90, and 120 mm/h). The PSD, sediment sorting process, and sediment particle agglomeration degree under the different slope conditions were compared to evaluate the influence of hedgerows on the size selectivity of eroded sediment during water erosion. Moreover, the direct and indirect effects of hedgerows on the sorting process and sediment particle agglomeration degree were revealed via correlation analysis and partial least squares path modelling (PLS–PM). Compared with those under CK slope conditions, the average clay, fine silt, and coarse silt contents under R slope conditions decreased by 1.37%, 0.06%, and 1.71%, respectively, whereas the sand content increased by 0.46%. Under P slope conditions, the average clay, fine silt, and coarse silt contents increased by 32.61%, 38.71%, and 36.14%, respectively, whereas the average sand content decreased by 47.30%. Under CK slope conditions, sediment sorting occurred primarily during the early stages of rainfall. R slope conditions caused an increase in the duration of early‐stage sediment sorting but caused a reduction in the degree of sorting, whereas P slope conditions exhibited interceptive sorting of sand throughout the rainfall event. Under R slope conditions, more aggregates were dispersed into individual particles due to raindrop impact, whereas under P slope conditions, more fine particles aggregated initially, but loose aggregates were dispersed into individual particles during the later rainfall stages. The enrichment rates of fine silt and coarse silt were positively correlated with slope conditions, whereas they were negatively correlated with the enrichment rate of sand. However, there was no significant relationship between the slope conditions and the aggregation rates of particles of various sizes. PLS–PM indicated that hedgerows directly and indirectly affect sorting processes and sediment particle agglomeration degree by regulating runoff and sediment erosion, and the direct effects exceed the indirect effects. These findings provide a comprehensive understanding of the influential mechanisms of hedgerows on controlling soil erosion.
侵蚀沉积物的粒径分布（PSD）可有效反映侵蚀过程的变化。绿篱具有显著的水土保持效益，并能影响侵蚀过程。然而，绿篱对侵蚀沉积物粒径分布的影响仍不清楚。因此，建立了三种坡度条件（对照检查，CK；仅灌木树篱根部，R；整个灌木树篱，P），涉及两种坡度（15 和 25°）的配置，并在三种降雨强度（60、90 和 120 mm/h）下进行了模拟降雨实验。比较了不同坡度条件下的 PSD、沉积物分选过程和沉积物颗粒团聚程度，以评价水流侵蚀过程中绿篱对侵蚀沉积物粒径选择性的影响。此外，还通过相关分析和偏最小二乘路径模型（PLS-PM）揭示了绿篱对分选过程和泥沙颗粒团聚程度的直接和间接影响。与 CK 坡条件相比，R 坡条件下粘土、细粉砂和粗粉砂的平均含量分别减少了 1.37%、0.06% 和 1.71%，而含沙量则增加了 0.46%。在 P 坡条件下，粘土、细粉砂和粗粉砂的平均含量分别增加了 32.61%、38.71% 和 36.14%，而砂的平均含量则减少了 47.30%。在 CK 坡条件下，沉积物分选主要发生在降雨初期。在 R 坡条件下，早期阶段的沉积物分选持续时间延长，但分选程度降低；而在 P 坡条件下，整个降雨过程中沙子都在相互分选。在 R 坡条件下，由于雨滴的冲击，更多的聚集体分散成单个颗粒，而在 P 坡条件下，更多的细颗粒在降雨初期聚集，但松散的聚集体在降雨后期分散成单个颗粒。细粉砂和粗粉砂的富集率与坡度条件呈正相关，而与砂的富集率呈负相关。然而，坡度条件与各种大小颗粒的聚集率之间没有明显关系。PLS-PM表明，绿篱通过调节径流和泥沙侵蚀直接和间接地影响分选过程和泥沙颗粒聚集度，且直接影响大于间接影响。这些发现使人们对绿篱控制水土流失的影响机制有了全面的了解。
{"title":"Hedgerows enhance the size selectivity of eroded sediment from sloping farmland under simulated rainfall experiment","authors":"Hai Xiao, Junkui Guo, Zhenyao Xia, Ping Guo, Feng Gao, Rui Xiang, Deyu Liu, Yu Ding, Di Wang, Lun Zhang","doi":"10.1002/esp.5979","DOIUrl":"https://doi.org/10.1002/esp.5979","url":null,"abstract":"The particle size distribution (PSD) of eroded sediment can effectively reflect changes in erosion processes. Hedgerows provide significant soil and water conservation benefits and influence erosion processes. However, the impact of hedgerows on the PSD of eroded sediment remains unclear. Therefore, three slope conditions (control check, CK; only hedgerow root, R; and whole hedgerow, P) involving the configuration of two slope gradients (15 and 25°) were established, and simulated rainfall experiments were conducted under three rainfall intensities (60, 90, and 120 mm/h). The PSD, sediment sorting process, and sediment particle agglomeration degree under the different slope conditions were compared to evaluate the influence of hedgerows on the size selectivity of eroded sediment during water erosion. Moreover, the direct and indirect effects of hedgerows on the sorting process and sediment particle agglomeration degree were revealed via correlation analysis and partial least squares path modelling (PLS–PM). Compared with those under CK slope conditions, the average clay, fine silt, and coarse silt contents under R slope conditions decreased by 1.37%, 0.06%, and 1.71%, respectively, whereas the sand content increased by 0.46%. Under P slope conditions, the average clay, fine silt, and coarse silt contents increased by 32.61%, 38.71%, and 36.14%, respectively, whereas the average sand content decreased by 47.30%. Under CK slope conditions, sediment sorting occurred primarily during the early stages of rainfall. R slope conditions caused an increase in the duration of early‐stage sediment sorting but caused a reduction in the degree of sorting, whereas P slope conditions exhibited interceptive sorting of sand throughout the rainfall event. Under R slope conditions, more aggregates were dispersed into individual particles due to raindrop impact, whereas under P slope conditions, more fine particles aggregated initially, but loose aggregates were dispersed into individual particles during the later rainfall stages. The enrichment rates of fine silt and coarse silt were positively correlated with slope conditions, whereas they were negatively correlated with the enrichment rate of sand. However, there was no significant relationship between the slope conditions and the aggregation rates of particles of various sizes. PLS–PM indicated that hedgerows directly and indirectly affect sorting processes and sediment particle agglomeration degree by regulating runoff and sediment erosion, and the direct effects exceed the indirect effects. These findings provide a comprehensive understanding of the influential mechanisms of hedgerows on controlling soil erosion.","PeriodicalId":11408,"journal":{"name":"Earth Surface Processes and Landforms","volume":null,"pages":null},"PeriodicalIF":3.3,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142199197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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