Catena最新文献

{"title":"Development stage of biocrusts regulates soil carbon mineralization and its hydrothermal sensitivity in a temperate desert ecosystem","authors":"Xiaojun Li ,&nbsp;Haotian Yang ,&nbsp;Dinghai Zhang ,&nbsp;Jingyao Sun ,&nbsp;Rong Yang","doi":"10.1016/j.catena.2025.109311","DOIUrl":"10.1016/j.catena.2025.109311","url":null,"abstract":"<div><div>Biocrusts play a vital role in modulating soil carbon dynamics within dryland ecosystems. However, our understanding of soil organic carbon mineralization in biocrusts at different developmental stages remains rather limited, impeding accurate quantification of C sequestration in drylands. In this study, we measured the mineralization rates across a successional gradient encompassing mobile sand dunes (MSD), bare soil patch (BS), and cyanobacteria- (CC), lichen- (LC), and moss-dominated (MC) biocrusts, and the relationships among mineralization rates, soil properties, and soil water content and temperature, were examined. The results demonstrated that instantaneous (R_m), maximum (MR_m), and average (AR_m) mineralization rates, and cumulative CO₂-C release (CR) exhibited progressive amplification along the developmental sequence, regardless of soil layer and varying levels of soil moisture and temperature. Specifically, AR_m over the whole incubation period in biocrust layer were 10.19(±1.15)-30.02(±1.86) times greater than that in MSD and 0.27(±0.11)-1.66(±0.20) times greater than that in BS. In subsoils, this variable was 1.84(±0.15)-5.43(±0.73) times higher than that in MSD, and 0.17(±0.02)-1.03(±0.35) times higher than that in BS, with the magnitude depending on the levels of soil moisture and temperature. It increased by 24.88(±9.43)-52.19(±2.36) % in biocrust layer, whereas by 32.08(±13.94)-61.24(±13.41) % in subsoil when biocrust succeeded from CC to MC across the incubation. Notably, biocrust development induced a dual carbon regulation mechanism, although the absolute pool of potentially mineralizable SOC in both the upper layer and subsoil increased significantly with biocrust development, its proportion relative to total SOC decreased, indicating enhanced mineralization capacity but reduced mineralization efficiency as biocrust matured. The mineralization rates of both biocrusts and subsoils increased significantly with increasing levels of soil moisture and temperature, regardless of biocrust development stages, and the sensitivity of mineralization rates in both layers to soil moisture and temperature increased as biocrusts progressed in their development. Remarkably, biocrusts accounted for over 45.18% of the total CO₂-C released across all scenarios, corroborating their key role in SOC dynamics in drylands. The structural equation model (SEM) analysis indicated that changes in soil physicochemical and microbial properties caused by biocrust development were the key driving factors regulating SOC mineralization. These findings reveal that biocrust development establishes a dual carbon control framework: stimulating transient mineralization through regulating driving factors while promoting long-term stabilization, which has critical implications for dryland carbon resilience under climate change scenarios.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109311"},"PeriodicalIF":5.7,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Permafrost degradation due to fire disturbance: A case study in the Da Xing’anling mountains, Northeastern China","authors":"Yapeng Cao ,&nbsp;Guoyu Li ,&nbsp;Wei Ma ,&nbsp;Yujun Cui ,&nbsp;Dun Chen ,&nbsp;Kai Gao ,&nbsp;Juncen Lin ,&nbsp;Changqing Li ,&nbsp;Anshuang Su","doi":"10.1016/j.catena.2025.109323","DOIUrl":"10.1016/j.catena.2025.109323","url":null,"abstract":"<div><div>Xing’an permafrost (XAP), widely distributed in the Da Xing’anling Mountains in northeastern China, is an ecosystem − dependent permafrost type that is highly sensitive to vegetation and surface insulation. To investigate its response to a unique form of human − induced fire disturbance (HIFD) — prescribed firebreak burning (PFB) — an on − site monitoring system was established in a PFB − affected area. Ground temperatures were continuously recorded from 2019 to 2024 to assess the thermal effects of PFB. Meanwhile, electrical resistivity tomography (ERT) testing was conducted in the PFB region. The recorded data indicated that, as a result of PFB, thawing interlayers were formed in cold seasons, and the thawing interlayer base gradually moved downwards. The seasonal thawing depth (STD) was observed to increase in warm seasons. Ground temperatures in deeper strata continued to rise, but the rate of permafrost warming gradually decreased with increasing depth. The permafrost thickness was found to continuously decrease. In future, with continuous PFB, the XAP is expected to experience complete degradation. The ERT profiles showed a smaller permafrost area and higher ground temperatures in the PFB region than in the areas without PFB, with the rise of ground temperature being most pronounced in the shallowest stratum. Water ponding and human construction practices also contributed to the severe degradation of the XAP, but the influencing mechanism on the permafrost differs for the three types of disturbance. The findings of this study provide a reference for studies of the effect of PFB on the evolution of XAP, and also provide guidance for the installation of fire isolation barriers in XAP regions of northeastern China.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109323"},"PeriodicalIF":5.7,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanisms and drivers of soil pH assessed by Shapley additive explanation","authors":"Azamat Suleymanov ,&nbsp;Yakov Kuzyakov ,&nbsp;Ilgiz Asylbaev ,&nbsp;Igor Rusakov ,&nbsp;Ruslan Suleymanov ,&nbsp;Iren Tuktarova ,&nbsp;Larisa Belan","doi":"10.1016/j.catena.2025.109301","DOIUrl":"10.1016/j.catena.2025.109301","url":null,"abstract":"<div><div>Soil pH is a critical property influencing soil health and functions, nutrient availability and microbial activities, and agricultural productivity. Interpreting machine learning models in soil science is a challenge, despite their increasing application. We used a dataset of 2651 soil samples up to 60 cm depth to understand the drivers controlling spatial and depth distribution of soil pH and related them to soil-forming factors in foothills mountains and semi-arid steppes of southern Ural (Russia). Machine learning approach allowed to analyse the effects of key soil-forming factors (climate, topography, vegetation, soil and parent materials) for the predictions and the role of covariates utilizing Shapley values, a game theory-based method to quantify the average marginal contribution of a predictor. The developed models explained 62 %, 56 % and 54 % of the pH variation in 0–20, 20–40 and 40–60 cm, respectively. Climate (precipitation, cloud cover and surface temperature), soil type and elevation were the most important factors of soil pH across all depths. When precipitation in December exceeds 30–35 mm, cloud cover 58–60 % and elevation 400–450 m, the model predicted a lower pH compared with a mean level across all depths. The generated pH maps also revealed a change in soil pH from mountainous forested ecosystems to semi-arid steppe landscapes. These findings are mainly explained by the difference in precipitation-driven leaching and evapotranspiration-induced salt accumulation in soils in the area (9,500 km²). Our study underscores the complexity and non-linearity of the relationships between pH and the environmental variables, providing valuable insights into their variations across both horizontal and vertical spatial dimensions.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109301"},"PeriodicalIF":5.7,"publicationDate":"2025-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatiotemporal changes of Mollic Horizon thickness based residual random forest in typical province of northeastern China","authors":"Gao Zhang ,&nbsp;Ma Lixia ,&nbsp;Yu Dongsheng ,&nbsp;Hu Wenyou ,&nbsp;Kuang Enjun ,&nbsp;Ding Qixun ,&nbsp;Zhao Yuguo","doi":"10.1016/j.catena.2025.109327","DOIUrl":"10.1016/j.catena.2025.109327","url":null,"abstract":"<div><div>The thickness of the Mollic Horizon, a key indicator of soil quality, and its rate of decline are critical for ensuring food security. Current assessments of Mollic Horizon thickness primarily rely on statistical reports and soil erosion studies, which inadequately capture regional spatial patterns. Predicting spatial changes in Mollic Horizon thickness is essential for understanding large-scale trends. However, existing models, while accurate at small watershed scales, often yield substantial errors at regional scales. To address these limitations, this study applied a rapid investigation method (RIM), resulting in a dataset of 357 Mollic Horizon thickness measurements from 2022. A Converting Soil Horizon Depth into Mollic Horizon Thickness (CSMH) method was used to reconstruct the historical thickness dataset from 1746 soil profiles investigated in 1982. To enhance prediction accuracy, the study developed the Residual Random Forest (RRF) and Residual Quantile Regression Forest (RQRF – an uncertainty-aware extension modeling conditional quantiles of residuals) models, generating high-precision spatial distribution maps of Mollic Horizon thickness for two periods. As a benchmark of traditional soil profile survey (TSP) data, the improved RIM methods achieved an accuracy of 95.32 %, and CSMH achieved 86.17 % on Mollic Horizon thickness using surveyed profile data in 2023, demonstrating their data suitability from alternatives methods. The RRF model exhibited high spatial explanatory power (R² &gt; 0.79) and a low error (RMSE &lt; 10.01 cm), supporting accurate regional-scale mapping. Over the past 40 years, Mollic Horizon thickness of cultivated land in Heilongjiang Province decreased by 0.27 cm/year, based on both investigation site statistics and continuous spatial analysis. Significant thinning was observed in the Songnen and Sanjiang Plains due to long-term cultivation, whereas thickening occurred in low-lying cultivated lands near hilly and mountainous areas. These findings provide robust data and methodological advances for Mollic Horizon protection in Northeast China.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109327"},"PeriodicalIF":5.7,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying the spatiotemporal evolution and driving factors of soil erosion in the source region of the Yellow River using 137Cs and machine learning models","authors":"Jinxi Su,&nbsp;Zhenying Zhou,&nbsp;Juncheng Li,&nbsp;Mengyao Long,&nbsp;Huilong Lin","doi":"10.1016/j.catena.2025.109296","DOIUrl":"10.1016/j.catena.2025.109296","url":null,"abstract":"<div><div>The source region of the Yellow River (SRYR), known as the “Water Tower of China”, is not only crucial for the sustainability of alpine grassland and wetland ecosystems, but has significant implications for water quality and sediment deposition in the river’s middle and lower reaches. However, complex topography, climate, and diverse soil erosion types limit the applicability of traditional estimation methods. This study developed a tailored compound erosion prediction model for the SRYR to quantify erosion rates and identify their driving mechanisms. A dataset of 537 soil erosion rates from ¹³⁷Cs and 33 conditioning variables were used to construct an optimal model. Two variable selection methods—genetic algorithm (GA) and least absolute shrinkage and selection operator (LASSO)—were applied alongside three machine learning algorithms: categorical boosting (CatBoost), random forest (RF), and k-nearest neighbors (KNN). Geographical detectors were used to identify erosion drivers. Key findings include: (1) The GA-CatBoost model outperformed others (R_test² = 0.51). Based on optimal model, the estimated annual soil erosion rate (2001–2022) in the SRYR was 20.21 t·ha⁻¹·a^-1, with total annual erosion of 238.80 × 10⁶ t·a^-1. (2) Spatial analysis revealed high erosion in the northwest, low in the southeast, and mixed patterns in the central region, with 78.28 % of the SRYR exhibiting improvement over 2001–2022. (3) Precipitation and NDVI were identified as the dominant driving factors mitigating soil erosion in the SRYR. These findings demonstrate the effectiveness of ecological restoration efforts in the SRYR, providing empirical evidence for targeted soil and water conservation strategies. Future studies could enhance model accuracy by diversifying sampling, measuring erosion rates during shorter time windows and using higher resolution input data.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109296"},"PeriodicalIF":5.4,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144714311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asynchronous changes and driving mechanisms of water-sediment transport in the Jinsha River Basin: Response to climate change and human activities","authors":"Juying Sun,&nbsp;Genxu Wang,&nbsp;Shouqin Sun,&nbsp;Shijun Chen,&nbsp;Xiangyang Sun,&nbsp;Yuanming Wang,&nbsp;Hailong Sun,&nbsp;Chunlin Song,&nbsp;Shan Lin,&nbsp;Zhaoyong Hu","doi":"10.1016/j.catena.2025.109325","DOIUrl":"10.1016/j.catena.2025.109325","url":null,"abstract":"<div><div>Climate change and human disturbances have significantly influenced hydrological processes in mountainous basins. The Jinsha River Basin (JSRB), a crucial source region of the Yangtze River, has experienced substantial changes in water–sediment processes, yet the combined effects of climate change, hydropower development, and ecological restoration programs remain poorly understood. A combination of partial derivative analysis and partial least squares regression was used to investigate the driving forces of changes in water–sediment transport from 1960 to 2020. Water discharge (WD) and sediment load (SL) both showed minor changes from 1960 to 1997 but a notable decoupling during 1998–2020. Before 1998, WD consistently showed slight declines, while SL exhibited a slight increase after a slight decrease due to industrial activities and reduced potential evapotranspiration (PET). During 1998–2020, WD decreased by 1.18 %/year (p &lt; 0.05) due to decreased precipitation (PRE) and increased PET, which offset the increased WD in the source region. Meanwhile, SL experienced a sharper decline of 6.97 %/year (p = 0.000), which was mainly due to damming (67.03 %) and revegetation (22.95 %) in the middle-lower reaches. During the single-reservoir period (1998–2009), decreased PRE (69.15 %) and revegetation (30.82 %) dominated SL reduction, while damming (160.38 %) and revegetation (12.89 %) were the major controlling factors for SL decrease during the cascade-reservoir period (after 2010). Our study highlights that although hydropower development has been the dominant factor in sediment reduction since 1998, climate change and ecological restoration programs also played significant roles in the JSRB. These findings provide valuable insights for water-sediment regulation and watershed management.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109325"},"PeriodicalIF":5.4,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144711797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk and driving factors of nitrogen and phosphorus runoff losses under extreme rainfall conditions: sludge application strategies in forest soils","authors":"Yuantong Yang ,&nbsp;Xiaojun Ge ,&nbsp;Weixun Feng ,&nbsp;Lihua Xian ,&nbsp;Guodong Shao ,&nbsp;Jianbo Liao ,&nbsp;Shucai Zeng","doi":"10.1016/j.catena.2025.109318","DOIUrl":"10.1016/j.catena.2025.109318","url":null,"abstract":"<div><div>Sewage sludge (SS), enriched with organic matter (OM), nitrogen (N), and phosphorus (P), holds the potential for rehabilitating degraded forest soils, yet poses non-point pollution risks through rainfall-induced nutrient migration. We systematically quantified N and P losses under five SS application rates using six simulated rainfall events (90 mm·h⁻¹). Results showed that SS amendment increased interflow and sediment erosion, while reducing surface runoff. Cumulative nutrient losses increased proportionally with the application rates. Surface runoff was responsible for 43.5 % of total nitrogen (TN) transport, whereas sediments mediated 96.2 % of P loss. Notably, interflow exhibited TN concentrations that were 6–70 times higher than other pathways, and its contribution to N loss increased from 16.2 % to 40.6 % following SS application. The first flush effect on ammonium nitrogen and nitrate nitrogen (AN and NN) was detected in the surface runoff, while increased exports of organic nitrogen (ON) and AN were observed in interflow. SS application preferentially enriched N and P in 0.25–1 mm sediment particles, raising the percentage of TN carried by this fraction from 12.5 % to 37.9 % and that of total phosphorus (TP) from 11.8 % to 35.8 %. Multivariate analysis indicated SS application rate, rainfall frequency, and particle size as the key drivers that modulate nutrient loss by modifying soil porosity. Ecological risk assessments recommend limiting SS application to ≤6 kg·m⁻² in eucalyptus plantations to reduce nutrient leaching, protect groundwater, and adjacent aquatic environments. Our findings provide important insights into how SS can be sustainably applied as a soil amendment, while minimizing the environmental risk of N and P loss from forest soils through runoff.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109318"},"PeriodicalIF":5.4,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144711796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the effectiveness of four representative land uses in soil and water conservation on a typical rainfed Mediterranean agricultural landscape in La Rioja (Spain)","authors":"Wendi Wang ,&nbsp;Manel Llena ,&nbsp;Estela Nadal-Romero ,&nbsp;Teodoro Lasanta ,&nbsp;Paolo Tarolli","doi":"10.1016/j.catena.2025.109313","DOIUrl":"10.1016/j.catena.2025.109313","url":null,"abstract":"<div><div>Mediterranean steep-slope agricultural landscapes are highly vulnerable to soil erosion, exacerbated by climate and land use changes. In Spain, the 1992 EU Common Agricultural Policy reform led to an increase in tilled, unseeded fallow land, altering soil erosion dynamics. However, systematic research comparing the hydrological and soil conservation performance of fallow land versus traditional crops remains limited.</div><div>This study addresses this gap by evaluating the hydrological and sedimentary responses of tilled, unseeded fallow land compared to three representative Mediterranean crops—olive, vineyard, and barley—on steep slopes in La Rioja, Spain. We propose a flexible modelling approach (SIMulated Water Erosion model; SMIWE) to determine suitable land use for steep-slope agriculture in the region by simulating water and soil movement during extreme rainfall, which is expected to become more frequent due to climate change.</div><div>The analysis examines and compares differences in hydro-sedimentary outputs, including surface water depth, sediment flux, and erosion rates. Results show that fallow land had the lowest surface water depth 0.001 m, but the highest sediment flux 0.04 kg m⁻¹ s⁻¹ and erosion rate (39 % higher than vineyards). Among cultivated lands, vineyards had the lowest sediment flux and erosion rates, with 13 % lower than olive and 2 % lower than barley fields. Total erosion in fallow land was significantly higher than in other land uses, followed by olive, barley, and vineyards. Despite the uncertainty and the limitations of the modelling exercise, these findings highlight the vulnerability of unseeded fallow land to soil erosion and underscore the importance of crop selection and management strategies for improving landscape resilience and sustainability.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109313"},"PeriodicalIF":5.4,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144703075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clay mineral assemblages of the Luojiawopeng Formation red bed in the Songnen Plain, NE China and their paleoenvironment implications","authors":"Jie Meng ,&nbsp;Benxian Li ,&nbsp;Lei Sun ,&nbsp;Xiaofeng Wang ,&nbsp;Juncheng Zhang ,&nbsp;Zhenyu Wei ,&nbsp;Yanru Wang ,&nbsp;Yunping Chi ,&nbsp;Yuanyun Xie ,&nbsp;Weiguang Shi","doi":"10.1016/j.catena.2025.109324","DOIUrl":"10.1016/j.catena.2025.109324","url":null,"abstract":"<div><div>The Luojiawopeng (LJWP) Formation red bed is proluvial fan deposits and distributed in the eastern Songnen Plain, NE China. Its stratigraphic age has been assigned to the early Early Pleistocene based on lithologic stratigraphic correlation. However, the paleoenvironmental characteristics of the red bed remain poorly resolved, which limits our in-depth understanding of how the red sediments were formed during the global cooling period, particularly in northeastern China. To address this gap, we report on the clay mineral assemblages of the LJWP Formation red bed and the associated paleoenvironment during its sedimentation period. Based on the analysis of XRD, SEM, EDS and HRTEM, the results indicate that the clay minerals in the LJWP Formation strata are primarily composed of kaolinite (57–73 %), illite (25–41 %), and biotite/vermiculite (0–4 %). The pseudo-hexagonal plate-like shapes suggest an authigenic origin of the kaolinite, indicating that the LJWP Formation strata underwent intensive chemical weathering. The hydrolysis processes in the LJWP Formation are thus deduced as follows: illite → kaolinite, biotite → biotite/vermiculite → kaolinite. Significant amounts of iron were released from both the crystal structure of biotite and its secondary clay minerals during weathering processes, resulting in nanoscale hematite precipitating on the surfaces and within the pores of particles, as shown by the HRTEM and petrographic examination. Accordingly, based on these findings, we conclude that the secondary hematite minerals imparted a reddened staining to the LJWP Formation deposits, and that the LJWP Formation red bed accumulated during a period of warm and humid conditions. Recent research based on geochemical and heavy mineral contents supports the presence of the warm climatic conditions, challenging the previously held view that this red bed originated from glacial tills formed under cold climatic conditions.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109324"},"PeriodicalIF":5.4,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144703140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sediment organic carbon dynamics and accumulation in estuarine mangrove wetlands","authors":"Jian Gong ,&nbsp;Weiwei Liu ,&nbsp;Wei Li ,&nbsp;Lijuan Cui","doi":"10.1016/j.catena.2025.109317","DOIUrl":"10.1016/j.catena.2025.109317","url":null,"abstract":"<div><div>Estuarine mangrove wetlands are important carbon sinks, yet the mechanisms driving sediment organic carbon (SOC) accumulation and burial remain insufficiently understood. Here, we present comprehensive insights into the distribution, sources, and decomposition of SOC and its fractions, as well as temporal variations in organic carbon accumulation rate (OCAR), across a land-to-sea gradient in mangrove and unvegetated habitats. Our results show that SOC content and storage are significantly higher in mangrove habitats compared to unvegetated ones, both of which decrease with increasing sediment depth, primarily controlled by bulk density (BD) and sediment water content (SWC). Similarly, the distribution patterns of active organic carbon fractions, including easily oxidizable organic carbon, microbial biomass carbon, and dissolved organic carbon, exhibit similar spatial patterns to SOC across habitats. Stable isotope analyses (δ¹³C and δ¹⁵N) and lignin biomarkers reveal that SOC decomposition is markedly higher in mangrove habitats than in unvegetated areas, potentially driven by plant inputs that enhance microbial processes and accelerate carbon turnover. The contribution of C3 vascular plant-derived terrestrial organic carbon declines significantly along the land-to-sea gradient (from 62.8 % in mangrove habitats to 28.0 % in unvegetated areas), likely due to reduced in situ plant inputs. Structural equation modeling results indicate that sediment accumulation rate (SAR), BD, and SWC are key environmental factors influencing OCAR, while other relevant environmental factors may also contribute. This study enhances our understanding of carbon cycling mechanisms in mangrove wetlands and provides a scientific foundation for their conservation and management.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"259 ","pages":"Article 109317"},"PeriodicalIF":5.4,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144703173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}