Geomorphology最新文献_第10页

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2026-01-01

引用次数: 0

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2026-01-01

引用次数: 0

Gully erosion susceptibility assessment and SHAP interpretability analysis in sloping farmland of soil-rock dual structure area: A case study of Yimeng Mountain area, China 土石二元结构区坡耕地沟沟侵蚀敏感性评价及SHAP可解释性分析——以沂蒙山区为例

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-30 DOI: 10.1016/j.geomorph.2025.110146

Ziming Zheng , Tingting Yan , Weijun Zhao , Wei Qin , Chunyang Huang , Yi Wang , Zhen Li

Gully erosion, as a typical form of hydraulic erosion, is a major driver of soil degradation on sloping farmland and poses a serious threat to agricultural production and food security. Accurate and automated identification of gully erosion susceptibility (GES) therefore remains an urgent challenge. In regions with a soil-rock dual structure, soils are thin, heterogeneous, and weakly developed, and gully erosion is highly prevalent. Thus, it is essential to incorporate underlying-surface factors such as rock fragment content and soil thickness into susceptibility assessment. With the Yimeng Mountain area of northern China as a case study, five modelling approaches were developed including machine learning (Random Forest, RF and eXtreme Gradient Boosting, XGBoost), multivariate regression (Logistic Regression, LR), and deep learning (Transformer and Convolutional Neural Network, CNN). SHapley Additive exPlanations (SHAP) was applied for model interpretability. The results showed that: (1) The RF model achieved the highest prediction accuracy (ACC = 0.9534, AUC = 0.9809), outperforming LR, XGBoost, CNN, and Transformer. (2) In the susceptibility map produced by integrating RF, XGBoost, and LR, high and very high susceptibility zones account for 47 % of the study area. (3) 15 influencing factors contribute to gully erosion, among which topographic wetness index (TWI), slope, and distance to rivers are the most significant drivers. Areas with high wetness (TWI > 8–10), gentle slopes (10–15°), and proximity to rivers (<2000 m) exhibit a high likelihood of gully initiation and development. Under deep soil conditions, the combination of high TWI and short distances to rivers strongly promotes gully erosion, whereas higher rock fragment content on steep slopes helps to inhibit it. By automatically generating gully erosion susceptibility maps (GESMs), this study effectively identifies high-risk zones for gully initiation and expansion, providing robust scientific support for gully erosion control, farmland protection, land-use management, and sustainable agricultural development.

沟沟侵蚀作为一种典型的水力侵蚀形式，是坡耕地土壤退化的主要驱动因素，对农业生产和粮食安全构成严重威胁。因此，沟蚀敏感性的准确和自动识别仍然是一个紧迫的挑战。在土岩二元结构地区，土壤较薄、不均匀、发育较弱，沟壑侵蚀较为普遍。因此，将岩石破碎块含量、土壤厚度等下垫面因素纳入敏感性评价中是十分必要的。以中国北方沂蒙山地区为例，开发了五种建模方法，包括机器学习（随机森林，RF和极端梯度增强，XGBoost），多元回归（Logistic回归，LR）和深度学习（变压器和卷积神经网络，CNN）。模型可解释性采用SHapley加性解释（SHAP）。结果表明：(1)射频模型的预测精度最高（ACC = 0.9534, AUC = 0.9809），优于LR、XGBoost、CNN和Transformer。(2)在RF、XGBoost和LR综合绘制的敏感性图中，高和极高敏感性区占研究区面积的47%。(3) 15个影响因子对沟道侵蚀有影响，其中地形湿度指数（TWI）、坡度和与河流的距离是最显著的驱动因子。高湿度（TWI > 8-10）、缓坡（10-15°）和靠近河流（<2000 m）的地区极有可能出现沟壑的形成和发展。在深土条件下，高TWI和距离河流较近的组合强烈地促进了沟蚀，而陡坡上较高的岩屑含量有助于抑制沟蚀。该研究通过自动生成沟蚀敏感性图（GESMs），有效识别沟蚀形成和扩展的高发区，为沟蚀治理、农田保护、土地利用管理和农业可持续发展提供有力的科学支持。

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引用次数: 0

Evaluating long-term geomorphic responses and sediment budget impacts of threshold-based floods and sediment replenishment in the Naka River, Japan 基于阈值的洪水和沉积物补给对日本中江长期地貌响应和泥沙收支影响的评估

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-30 DOI: 10.1016/j.geomorph.2025.110150

Cheng Wei , Sameh A. Kantoush , Binh Quang Nguyen , Sohei Kobayashi , Jia Qi Lin , Tetsuya Sumi

Quantifying the geomorphic effectiveness of sediment replenishment (SR) in restoring riverine sediment continuity remains challenging under variable flow regimes in dam-regulated systems. This study investigates downstream sediment dynamics in the Naka River, Japan, by integrating threshold-based flood frequency analysis (Peak-Over-Threshold, POT), sediment grain size measurements for tracking the sediment source from the SR site, and multitemporal geomorphic change detection (GCD) between 2010 and 2015. An optimal discharge threshold of 357.55 m³/s was identified to delineate geomorphically significant flows, including the extreme 2014 event (5411 m³/s; 134-year return period), which drove substantial geomorphic change. Difference of Digital Elevation Models (DoD) of the bathymetric channel (period 2010–2011, 2011–2012, …, 2014–2015, and 2010–2015) revealed incision at the SR site (up to −0.89 m) and downstream aggradation (up to +0.65 m) in the meandering mid-reach (7–14 km), evidencing sediment dispersal from the replenishment site. Sediment budgets indicated peak gross erosion (27.98 Mm³) during 2013–2014, followed by stabilization. Cross-sectional analyses confirmed outer-bend erosion and inner-bend deposition, reflecting natural meander dynamics, while episodic reappearance of coarse grains in 2013 and 2017 suggested localized re-exposure or flood-driven remobilization. Sediment transport and deposition were strongly influenced by local channel curvature and typhoon-induced flows, with limited morphological change beyond 14 km due to Kawaguchi Dam backwater effects. This integrated POT–GCD approach effectively identifies geomorphically significant floods and quantifies their spatial influence, demonstrating that SR enhances downstream sediment delivery and channel adjustment, emphasizing the role of hydrology and sediment connectivity in restoring riverine sediment budgets.

量化泥沙补给（SR）在恢复河流泥沙连续性中的地貌有效性仍然具有挑战性。本研究采用基于阈值的洪水频率分析（Peak-Over-Threshold， POT）、沉积物粒度测量（用于追踪SR站点的沉积物来源）和2010 - 2015年间的多时段地貌变化检测（GCD），对日本Naka河下游的泥沙动态进行了研究。确定了357.55 m3/s的最佳流量阈值，以描绘具有地貌意义的流量，包括2014年的极端事件（5411 m3/s， 134年的重现期），该事件导致了实质性的地貌变化。2010-2011年、2011-2012年、2011-2012年、2014-2015年和2010-2015年等深河道的数字高程模型（DoD）的差异显示，在蜿蜒的中游（7-14 km），泥沙从补给点扩散，在SR位置有切口（最大达- 0.89 m），下游有堆积（最大达+0.65 m）。泥沙收支表明，总侵蚀在2013-2014年达到峰值（27.98 Mm3），随后趋于稳定。横断面分析证实了外弯侵蚀和内弯沉积，反映了自然曲流动力学，而2013年和2017年粗粮的间歇性再现表明局部再暴露或洪水驱动的再动员。输沙和沉积受局地河道曲率和台风流的强烈影响，14 km以外受川口坝回水影响的形态变化有限。这种综合的POT-GCD方法有效地识别了具有地貌意义的洪水，并量化了它们的空间影响，表明SR增强了下游输沙量和河道调整，强调了水文和泥沙连通性在恢复河流泥沙收支中的作用。

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引用次数: 0

Temporal and spatial dynamics of urban stream geomorphology: The role of effective imperviousness and development age 城市水系地貌的时空动态：有效不透水性和发展年龄的作用

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-30 DOI: 10.1016/j.geomorph.2025.110155

Lukman A. Soboyejo , Kathryn L. Russell , Tim D. Fletcher

Urbanisation has been widely studied for its impact on stream channel geomorphology, primarily using space-for-time substitution approaches. However, continuous monitoring of urban geomorphic responses, to understand the temporal dynamics and influence of development age, remains underexplored within this framework. In this study, we combined repeated field observations collected 13 years apart with land cover analysis to assess geomorphic change across a gradient of urbanisation. We addressed three research questions: (i) to what extent do space-for-time substitution interpretations align with directly observed changes in stream channel morphology, and are post-study changes in stream channels consistent with earlier observations? (ii) how has the change in the extent of urbanisation over the study period directly influenced observed changes in stream channel morphology? (iii) at what level of urban development is stream incision most severe (i.e., does channel morphology stabilise during the latter stages of urban development)? We found that predictions made through space-for-time substitution in 2011 (i.e. regression models) were largely consistent with relationships observed in 2024 following further urbanisation of the catchments. However, change in geomorphic attributes at each site over the 13-year period were not significantly related to change in effective impervious cover (EI), possibly due to lag in geomorphic responses to ongoing urbanisation, along with the presence of hardpoints such as rock protection in the urbanised streams. Notably, several individual sites did show signs of active channel adjustment; all of these sites had moderate levels of urbanisation (<30 % EI), which had developed relatively recently (in the last 25 years). Severe channel incision was also observed within this range, suggesting a critical window for morphological instability. Whether channels eventually stabilise (without heavy intervention to harden channels) remains uncertain. Overall, the findings reinforce the importance of validating space-for-time substitution approaches through repeated observations to better develop more reliable urban channel evolution and stream management strategies.

城市化对河道地貌的影响已被广泛研究，主要采用时空替代方法。然而，在这一框架内，对城市地貌响应的持续监测，以了解发展年龄的时间动态和影响，仍未得到充分探索。在这项研究中，我们将相隔13年的重复实地观测与土地覆盖分析相结合，以评估城市化梯度下的地貌变化。我们解决了三个研究问题：(i)时空替代解释在多大程度上与直接观察到的河流河道形态变化相一致，以及研究后的河流河道变化与早期观察结果一致？（ii）在研究期间，城市化程度的变化如何直接影响已观察到的河道形态变化？（iii）在城市发展的哪个阶段，河流切割最为严重（即，在城市发展的后期，河道形态是否趋于稳定）？我们发现，2011年通过时空替代（即回归模型）所做的预测与流域进一步城市化后2024年观察到的关系基本一致。然而，在13年的时间里，每个地点的地貌属性变化与有效不透水覆盖（EI）的变化没有显著相关性，这可能是由于地貌对持续城市化的响应滞后，以及城市化溪流中存在岩石保护等挂载点。值得注意的是，几个单独的网站确实显示出积极的渠道调整迹象；所有这些地点都有中等水平的城市化（30% EI），这些城市化发展相对较晚（过去25年）。在这个范围内也观察到严重的通道切口，提示形态不稳定的关键窗口。渠道最终是否会稳定（不需要大量干预来强化渠道）仍不确定。总的来说，研究结果强调了通过反复观察验证空间替代时间方法的重要性，以更好地制定更可靠的城市通道演变和流管理策略。

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引用次数: 0

Identifying gravel-sand transition zones in alluvial plains using normalized steepness index 利用归一化坡度指数识别冲积平原砂砾-砂过渡带

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-29 DOI: 10.1016/j.geomorph.2025.110151

Kazuki Yoshida , Mamoru Koarai

Identifying gravel-sand transition (GST) location, where riverbed sediments shift from coarse gravel to fine sandy-muddy materials, is crucial for assessing natural disaster risk. However, GST zones remain unidentified on Japan's landform classification maps, complicating disaster risk assessments. Therefore, here, we aimed to investigate differences in the formation zones of gravelly and sandy-muddy alluvial plains in Japan, and GST zones in previous studies both within and outside Japan. To this end, we analyzed the longitudinal valley slope (S) and upstream drainage area (A) of 118 rivers in median- to large-scale alluvial plains of Japan, calculated using digital terrain models derived from Light Detection and Ranging. Sediment types from the surface to a depth of 3 m were obtained from borehole log data. Additionally, we calculated S and A values for small- to median-scale alluvial plains across six regions of Japan with different river sedimentation environments. The transition from gravelly to sandy-muddy alluvial plains systematically occurred at a normalized steepness index (k_sn) value of 10–20 m^0.9. This threshold corresponded to the observed relationship between k_sn and the median grain size of riverbed sediments: when k_sn was below 20 m^0.9, fine-grained sediments, including sand, became dominant. This threshold is consistent with GST zones reported globally. As k_sn can be derived solely from terrain data, without requiring field observations, it offers a practical method for generating simple, area-based landform classification maps. This approach is especially useful for the rapid creation of hazard maps, such as those predicting liquefaction risk.

确定砾石-砂过渡（GST）位置，即河床沉积物从粗砾石向细砂-泥质物质转变的位置，对于评估自然灾害风险至关重要。然而，在日本的地形分类地图上，商品及服务税区域仍未确定，这使灾害风险评估变得复杂。因此，在此，我们旨在研究日本砂砾质和砂质泥质冲积平原的形成带与日本国内外前人研究的GST形成带的差异。为此，我们分析了日本中尺度冲积平原118条河流的纵向河谷坡度(S)和上游流域面积(A)，并使用基于Light Detection and Ranging的数字地形模型进行了计算。利用钻孔测井资料获得了地表至3 m深度的沉积物类型。此外，我们还计算了日本6个不同河流沉积环境的小到中尺度冲积平原的S和A值。砾石冲积平原向砂质泥质冲积平原的转变系统地发生在归一化陡度指数（ksn）为10 ~ 20 m0.9的范围内。该阈值与观测到的ksn与河床沉积物中位粒径之间的关系相对应，当ksn低于20 m0.9时，细粒沉积物（包括砂）占主导地位。这一阈值与全球报告的GST区域一致。由于ksn可以完全从地形数据中获得，而不需要实地观测，因此它为生成简单的、基于区域的地形分类图提供了一种实用的方法。这种方法对于快速创建危险图特别有用，例如预测液化风险。

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引用次数: 0

Toward an efficient framework for remote sensing of river bathymetry: Comparing sensors and algorithms on an inaccessible proglacial river in Alaska 迈向河流测深遥感的有效框架：在阿拉斯加一条难以接近的前冰川河流上比较传感器和算法

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-24 DOI: 10.1016/j.geomorph.2025.110140

Carl J. Legleiter , Christina M. Leonard , Paul A. Burger , Addison G. Pletcher , Paul J. Kinzel

Remote sensing can provide reliable information on river depths and this approach might be particularly valuable in areas that are difficult to survey via conventional field methods. In this study, we assessed the potential to map the bathymetry of an inaccessible proglacial river in Alaska from both aerial orthophotos and a multispectral satellite image. In addition, we evaluated a variety of depth retrieval algorithms with different input data requirements, including some methods that require field measurements of water depth for calibration and other techniques that can be applied even when such field data are not available. These approaches might enable more efficient use of remote sensing methods by resource management agencies. Our results suggest that bathymetric mapping along the turquoise-colored river we examined was not only feasible but highly accurate (

R^{2}

up to 0.94) for both types of image data. Algorithms that use paired observations of depth and reflectance to train depth retrieval models were the most accurate, with errors on the order of 15%–20% and little or no bias. Alternative techniques based on hydraulic and statistical concepts also led to strong agreement between predicted and observed depths but were more susceptible to systematic biases toward under- or over-estimation of depth. In contrast to clear-flowing streams, bathymetric mapping in this environment was enabled by a direct relationship between the depth and brightness of the water due to scattering by suspended sediment. In selecting an appropriate depth retrieval method, a compromise might need to be reached between the level of field effort invested and the accuracy of the resulting image-derived bathymetry. Standalone software for implementing these techniques is freely available.

遥感可以提供关于河流深度的可靠信息，这种方法在难以通过常规实地方法进行调查的地区可能特别有价值。在这项研究中，我们评估了从航空正射影像和多光谱卫星图像中绘制阿拉斯加一条难以进入的前冰川河流的测深图的潜力。此外，我们还评估了不同输入数据要求的各种深度检索算法，包括一些需要现场测量水深进行校准的方法，以及即使没有现场数据也可以应用的其他技术。这些办法可能使资源管理机构能够更有效地利用遥感方法。我们的研究结果表明，对于这两种类型的图像数据，沿着绿松石色的河流进行水深测绘不仅可行，而且精度很高（R2高达0.94）。使用深度和反射率成对观测来训练深度检索模型的算法是最准确的，误差在15%-20%之间，几乎没有偏差。基于水力和统计概念的替代技术也使预测深度和观测深度之间的一致性很强，但更容易受到对深度估计不足或过高的系统性偏差的影响。与清澈的溪流相比，由于悬浮沉积物的散射，这种环境中的水深和亮度之间的直接关系使水深测绘成为可能。在选择适当的深度检索方法时，可能需要在投入的现场工作水平和由此产生的图像衍生测深精度之间达成妥协。实现这些技术的独立软件是免费的。

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引用次数: 0

Early-onset of rapid deposition rates of the Mangshan loess challenges the classical hypothesis of full Yellow River connection during the late Pleistocene 芒山黄土早发的快速沉积速率挑战了黄河在晚更新世完全贯通的经典假说

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-24 DOI: 10.1016/j.geomorph.2025.110149

Yingyong Chen , Xiaodong Miao

Understanding the origin and evolution of the Yellow River is not only crucial for understanding the geomorphic and climatic history, but also pivotal due to its historical significance and ecological impact on China's environment. However, the timing of the full connection of the Yellow River, as a critical event in the genesis of this major river system, is still debated continuously. Among various competing hypotheses, the abrupt increase of deposition rates following paleosol 2 (S2 of Chinese loess sequence, starting at about 0.245 Ma at the late Pleistocene) of the Mangshan loess was considered as major evidence of the late Pleistocene hypothesis, which attributes this increase to a sudden connection of the Yellow River. Here we scrutinized the stratigraphy of the Mangshan loess and identified abrupt increase of deposition rates occurring significantly earlier (at layers L11, S10, S9, L8, L7, L3) than S2, undermining the late Pleistocene hypothesis of the Yellow River genesis in the perspective of time. Moreover, we attribute the abrupt deposition rates to episodic gully erosion of the Loess Plateau, a mechanism distinct from the late Pleistocene full-river connection hypothesis. Therefore, the hypothesis that the Yellow River fully connected during the late Pleistocene is mechanistically unsupported, suggesting this connection likely occurred much earlier than 0.245 Ma.

了解黄河的起源和演变不仅对了解地貌和气候历史至关重要，而且由于其历史意义和对中国环境的生态影响而至关重要。然而，作为这一主要水系形成过程中的一个关键事件，黄河完全贯通的时间仍然存在争议。在各种相互竞争的假说中，从晚更新世约0.245 Ma开始的古土壤2（中国黄土序列S2）沉积速率的突然增加被认为是晚更新世假说的主要证据，该假说将这种增加归因于黄河的突然连接。通过对芒山黄土地层的研究，发现其沉积速率的急剧增加（L11、S10、S9、L8、L7、L3层）明显早于S2层，从时间上破坏了黄河成因的晚更新世假说。此外，我们将突变沉积速率归因于黄土高原的幕式沟蚀，这一机制与晚更新世全河连接假说不同。因此，黄河在晚更新世完全连通的假设在力学上是不支持的，表明这种连接可能发生在0.245 Ma之前。

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引用次数: 0

Impact of large dams on the hydrological and sediment transport regime in the monsoon-dominated Krishna River Basin in India 大型水坝对印度季风主导的克里希纳河流域水文和泥沙运输制度的影响

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-23 DOI: 10.1016/j.geomorph.2025.110141

Shantamoy Guha

Large dams significantly alter natural hydrological and sediment transport regimes, particularly in monsoon-dominated basins. This study investigates the effect of three large dams in the monsoon-dominated Krishna River Basin using multi-decadal flow and suspended sediment concentration data from respective downstream gauging stations, divided into pre-dam and post-dam periods. Indicators of hydrological alteration, flow and sediment duration curve (FDC), sediment rating curve, hysteresis loop (HL), and cross-wavelet transform (XWT) analyses were utlized to assess dam-induced impacts. Sediment rating curve and HL analyses were conducted for both monthly averages and events exceeding 5-year return period flood. Results reveal monthly monsoonal flow and sediment load reductions of ∼27–63 % and ∼27–98 %, respectively, during post-dam period. Contrary, several non-monsoon months exhibit up to 2 orders of magnitude increase, reflecting artificial water releases for irrigation and hydropower generation. A consistent decline of annual maximum flow and variable responses for annual minimum flow and both annual maximum and minimum sediment load were observed during post-dam time. Comparison of post-dam FDCs relative to pre-dam FDCs exhibits a reduction of high-flow events and sustenance of low-flow events. Two out of three stations show increased coefficients and decreased exponents in monthly sediment rating curves, implying increased sediment availability at lower discharge but lesser transport efficiency. However, monthly HLs and high-flow HL and rating relationships remain largely unaffected. Finally, XWT analysis demonstrates strong pre-dam coherence (0.25–1-year periodicities) between flow and sediment, which weakens post-impoundment, indicating decoupling between flow and sediment. Collectively, these findings reveal that the dam-induced regulation suppresses natural variability, significantly altering the hydrological and sediment transport regime.

大型水坝极大地改变了自然水文和沉积物运输制度，特别是在季风主导的盆地。本研究利用来自各自下游测量站的多年代际流量和悬沙浓度数据，研究了季风主导的克里希纳河流域三座大型水坝的影响，并将其分为大坝建成前和大坝建成后两个时期。利用水文变化指标、流沙持续时间曲线（FDC）、泥沙等级曲线、滞回线（HL）和交叉小波变换（XWT）分析来评估大坝的影响。对月平均和超过5年汛期的事件进行了泥沙等级曲线和HL分析。结果显示，在大坝后期，月季风流量和泥沙负荷分别减少了~ 27 - 63%和~ 27 - 98%。相反，几个非季风月份的降雨量增加了2个数量级，这反映了灌溉和水力发电的人工放水。在坝后时期，年最大流量持续下降，年最小流量和年最大、最小输沙量均有不同的响应。与坝前fdc相比，坝后fdc减少了高流量事件，维持了低流量事件。3个站点中有2个站点的月输沙率曲线系数增大，指数减小，表明在低流量条件下输沙率增加，但输沙效率降低。然而，月活率和高流量活率与评分关系基本未受影响。最后，XWT分析显示，坝前水沙关联性较强（0.25 - 1年周期性），蓄水后减弱，表明水沙关联性不强。总的来说，这些发现揭示了大坝诱导的调节抑制了自然变率，显著改变了水文和泥沙运输制度。

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引用次数: 0

Spatial heterogeneity of gully erosion and its dominants in multiple spatial scales in the Rolling Hilly Region of Northeastern China 东北起伏丘陵区多空间尺度沟壑侵蚀空间异质性及其优势

IF 3.1 2区地球科学 Q2 GEOGRAPHY, PHYSICAL

Geomorphology

Pub Date : 2025-12-23 DOI: 10.1016/j.geomorph.2025.110147

Xin Liu , Dichen Wang , Yulan Chen , Dan Li

Gully erosion is a common global degradation process with high spatial heterogeneity, because its influencing factors vary greatly in different spatial scales. However, the analyses of gully erosion and its influencing factors at different scales are lacking. Given this, gully interpretation was conducted in 5005 grids (1 km × 1 km) sampled from an area of 17.75 × 10⁴ km² by the stratified random sampling method to obtain gully area density in grids, geomorphic zone, and whole region scales in the Black Soil Region of Northeast China. Climate, topography, land cover, and human activity factors, including 18 potential parameters, were selected to explore the causes of spatial differentiation in gully erosion by using interpretable machine learning models. The research results indicated that the correlation coefficient and Nash's efficiency coefficient from the interpretable machine learning models are greater than 0.77 in all zones, and their simulation accuracy is satisfactory. Regionally, the annual average temperature significantly drove the spatial differentiation in gullies, increasing it above 3 °C and inhibiting it below this threshold. The dominant factors for plains, platforms, hills, and mountains were snow cover days, annual average temperatures, annual average temperatures, and annual minimum temperatures, respectively. At the grid scale, the annual average temperatures and annual maximum temperatures were identified as dominant drivers of gully densities in 23.31 % and 22.42 % of the study area, respectively. The main controlling factors had a significant spatial scale effect on gully erosion, suggesting that prevention and control measures based on the dominant factors at multiple scales should be implemented to decelerate gully erosion, protecting the ecology and land resources.

沟蚀是一种常见的全球性退化过程，其影响因素在不同空间尺度上存在较大差异，具有高度的空间异质性。然而，对不同尺度的沟蚀及其影响因素的分析缺乏。基于此，采用分层随机抽样的方法，在17.75 × 104 km2的区域内采样5005个栅格（1 km × 1 km）进行沟谷解译，获得了东北黑土区栅格、地貌带和全区域尺度上的沟谷面积密度。采用可解释的机器学习模型，选取气候、地形、土地覆盖和人类活动因子（包括18个潜在参数），探讨沟壑区侵蚀空间分异的原因。研究结果表明，各区域可解释机器学习模型的相关系数和Nash效率系数均大于0.77，模拟精度较好。从区域上看，年平均气温对沟壑区空间分异有显著的驱动作用，在3℃以上增加了沟壑区空间分异，在3℃以下抑制了沟壑区空间分异。平原、台地、丘陵和山地的主导因子分别是积雪日数、年平均气温、年平均气温和年最低气温。在栅格尺度上，年平均气温和年最高气温分别在23.31%和22.42%的研究区对沟谷密度起主导驱动作用。主要控制因素对沟蚀具有显著的空间尺度效应，建议在多尺度上实施基于主导因素的防治措施，以减缓沟蚀，保护生态和土地资源。

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引用次数: 0