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[Display omitted] • Changes in BRL reflect human-land relations in KMA of Southwest China. • This paper summarizes the evolutionary stages of BRL. • Explaining changes in BRL from a socio-ecological system perspective. • We demonstrate the greening in KMA of Southwest China from a micro perspective. Rock exposure is a prerequisite for the emergence of bare rocky land (BRL), a severe ecological and environmental problem in karst mountain areas (KMA) of Southwest China, severely restricting the region's sustainable development. An in-depth analysis of the evolution of BRL in KMA of Southwest China based on socio-ecological perspectives is significant for promoting the region's sustainable development. This paper firstly analyzes the evolution of the social-ecological system and BRL and the transition of human-land relations in KMA of Southwest China, then selects a typical KMA, Huajiang Canyon in Guizhou Province, for a case study and applies ArcGIS to analyze the dynamics of the BRL of Huajiang Canyon in the past 60 years from 1969 to 2020, and reveals the reasons for the evolution of BRL. The results show that: (1) The evolution of BRL in KMA of Southwest China is closely related to the changes in the local socio-ecological environment. (2) The number, spatial distribution, and landscape pattern of BRL in the Huajiang Canyon from 1969 to 2020 underwent significant changes, with the area of BRL transitioning from an expansion phase to an accelerated shrinking phase and with prominent spatial dispersion characteristics. (3) The transition of the BRL of the Huajiang Canyon into forest grassland and economic and fruity forest land, and the transition of land use from production to ecology and eco-economy, have proved the greening of the KMA of Southwest China from a microscopic perspective. (4) This paper shows that the expansion and contraction of BRL areas can reflect the human-land relations in KMA of Southwest China. Finally, the development path proposed in this paper has a certain positive effect on promoting the future sustainable development of the KMA of Southwest China and can also provide a reference for developing other mountainous areas with similar situations. [ABSTRACT FROM AUTHOR]

• This paper provides a new idea for the genesis and evolution of loess tunnels in the Loess Plateau. • There are significant differences in the loess tunnel development density in the different topographic and micro-topographic units. • Spatial statistical modelling was employed to justify and predict the observed spatial distribution tendency of the loess tunnels. • The loess tunnel evolution process can be divided into five stages: the incubation stage, formation stage, development stage, failure stage, and withered stage. Loess tunnels are very common in the Loess Plateau, and they pose unique geological threats. Loess tunnels are often difficult to detect and control due to their concealment and sudden appearance. Thus far, research on the genesis and evolution of loess tunnels remains scarce. In this paper, the genesis and evolution mechanism of the loess tunnels in the Loess Plateau is studied in depth, and the location, shape, and size information are obtained via field investigations. The potential correlations between the loess sediment, the basic physical properties (depth, water content, particle size composition, collapsibility coefficient, and self-weight collapsibility coefficient), and the tunnel density are inferred based on the Pearson's correlation coefficients and tests on the physical and mechanical properties of the loess sediments. In addition, spatial statistical modelling is employed to justify and predict the observed spatial distribution of the loess tunnels assuming Gaussian Markov random fields. The formation of loess tunnels is due to a combination of factors, including the formation thickness, soil properties, joints and fissures, topography, hydrogeology, and climatic conditions. The thickness of the loess, loess sediment properties, and their spatial relationship jointly determine the material basis of the formation of the loess tunnels. The loess tunnels at different depths have different main controlling factors that are hierarchical by depth. The evolution process of loess tunnels can be divided into five stages: the incubation stage, formation stage, development stage, failure stage, and withered stage. The characteristics of each stage are discussed in detail. Our work provides novel insights into subsurface erosion from the aspect of soil tunnels. It improves our understanding of hill slope geomorphological evolution and also provides effective techniques for tunnel erosion control. [ABSTRACT FROM AUTHOR]

• Thermal effects on soil hydraulic and mechanical properties were investigated. • An increasing temperature decreased the soil Ψ in the middle stage of SWRC. • The soil cohesion increased as the power function with increasing soil Ψ. • The soil friction angle increased as the linear function with increasing soil Ψ. • The increase in soil temperature decreased soil matric suction and shear strength. The soil hydrologic and mechanical properties play an important role in the slope stability in the red soil hilly region of southern China. In this study, the red soil layers in a collapsing gully wall were used to investigate the effects of temperature on the soil water retention curve (SWRC) and shear strength. The results showed that the SWRCs of the red soil under different temperatures could be accurately described by the van Genuchten (VG) model (R 2 > 0.95, root mean square error (RMSE) < 0.024). An increasing temperature significantly decreased the soil water holding capacity (WHC), especially in the intermediate range of the SWRCs of the red soil. The soil saturated hydraulic conductivity (Ks) increased linearly with temperature. The soil cohesion and soil friction angle decreased by approximately 44.13% and 30.40% respectively when the soil water content increased from 0.24 cm3 cm−3 to 0.42 cm3 cm−3. The mean soil cohesion and soil friction angle decreased approximately 8.56 kPa and 1.34° respectively when the soil temperature increased from 25 °C to 40 °C. Regression analysis showed that the soil cohesion increased as the power function with increasing matric suction (0–2000 kPa), and friction angle increased as the linear function with increasing matric suction. These results illustrated that an increase in temperature will decrease soil matric suction and shear strength but enhance the soil infiltration rate under certain soil moisture levels. Therefore, the stability of a collapsing gully wall will sharply decrease under the conditions of high temperature and heavy rain in summer. [ABSTRACT FROM AUTHOR]

[Display omitted] • A review of the current status of rainfall erosivity development is provided. • The accurate estimation of rainfall erosivity poses a challenge to quantitative analysis of soil erosion. • The differences in climate and environmental conditions result in variations in the estimated rainfall erosivity models. • The characteristics of rainfall itself influence the development of standards for rainfall erosion. • Rainfall erosivity can be estimated using either kinetic energy models or simplified estimation models. Rainfall erosivity (R) is commonly used to measure water and soil loss by representing the degree of rainfall-induced soil erosion. However, methods for calculating rainfall erosivity vary significantly regarding regional climatic and precipitation characteristics. How to quantitatively illustrate rainfall erosivity remains a key issue for soil erosion monitoring. In this paper, we summarize the basic principles in calculating rainfall erosivity, as well as the relationships and differences among mainstream methods. By referring to experiences gained from previous studies, this paper aims to better summarize and analyze the current rainfall erosivity estimation models and space–time distribution, so as to avoid the confused use of each estimation model as well as to proposes future researches. Currently, there is a widespread utilization of simple algorithms for rainfall erosivity estimation, and statistical methods like machine learning are also seen in such applications. Besides, while many have proposed to quantify local-scale rainfall erosivity, significant limitations are recognized for large-scale estimations. Future researches that emerge recently developed technologies such as remote sensing are expected to further improve rainfall erosivity estimation. [ABSTRACT FROM AUTHOR]

• Scientific literature since 1920 is analysed quantitatively and qualitatively. • All cryospheric elements (glacier, snow, (perma) frost) are considered. • Almost half (46.2 %) of the papers focus on soil formation after glacier retreat. • Half of the papers study primarily direct interactions between cryosphere and soil. • Literature that covers geomorphodynamical changes is represented the least. A review of the status of research on high mountain soils and their alterations caused by changes in the cryosphere in the European Alps is given. Soils of high mountain environments are not only exposed to atmospheric warming, rising CO 2 levels, and changing precipitation patterns but also to climate-driven changes in the cryosphere. The massive reduction of glacier coverage as well as snow cover and (perma) frost extent can affect soils in various ways. We performed a comprehensive literature analysis and considered both the direct impacts (changes in surface coverage or ground thermal conditions) and indirect impacts (changing hydrosphere, lithosphere/geomorphodynamics, or biosphere) of cryosphere changes on soil. All considered studies had a multidisciplinary character: around 34 % of the articles covered two spheres (cryosphere, pedosphere), 40 % covered three spheres (cryosphere, pedosphere, and an additional sphere), and 26 % covered more than three spheres. Most studies focused on initial soil formation in glacier forefields. The impact of changing geomorphodynamics on soils is underrepresented in literature, even though it is one of the major consequences of changes in the cryosphere. We therefore finally discuss possible consequences of changing geomorphodynamics due to changes in the cryosphere for high mountain soils. [ABSTRACT FROM AUTHOR]

• DSM of SOC using different remote sensing data was reviewed. • Majority of studies were conducted on mixed land-use types followed by cropland. • Machine learning techniques were used more than (geo)statistical ones. • Terrain variables as predictors had the largest contribution to map SOC. • Data acquired by satellite sensors was employed more than the other types. Soil organic carbon (SOC) has attracted a lot of attention in the soil science community. Freely available remote sensing data combined with advanced digital soil mapping (DSM) techniques has led to a better understanding and management of SOC. This paper has considered the published literature with a focus on digital mapping of SOC using remote sensing data within 2010 to 2023 intervals. The objective was to consider all the important aspects of SOC prediction and mapping, including different land-use types, DSM algorithms, environmental variables, and remote sensing data sources. According to this review conducted on the 217 papers, cropland was the most popular type of land use. Regarding the DSM algorithms, random forest (RF) appeared in the largest number of studies. The terrain and spectral variables derived from the digital elevation model (DEM) and remote sensing images, were the highest demanding among all those used as input predictors. In addition, satellite platforms provided the largest portion of the remote sensing data used for the calibration of DSM models. This review provides quantitative insight into recent trends of SOC digital mapping using remote sensing technology while suggesting some directions for future development of the topic. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new regional wind erosion events assessment method based on RF model was developed. • Integration of probabilistic statistical thoughts into wind erosion process studies. • Identification of the spatial distribution characteristics of threshold wind velocity. • Occurrence probability of wind erosion is assessed on a high-spatial-resolution scale. • 19.41 % of the study area has annual cumulative wind erosion duration near 1.5 months. The importance of air density variations in aeolian sand movement investigations is currently attracting widespread consideration. For this purpose, the spatial distribution characteristics of threshold wind velocity under the influence of air density are determined. To better understand the occurrence conditions of wind erosion events at different spatiotemporal scales, the present paper regards the air density metric as a bridge linking wind speed distribution and threshold wind velocity, reveals the coupling relationship between air density and wind speed by introducing the statistical distribution function method of probabilistic statistical thoughts, and accomplishes the scaling up of wind speed distribution parameters according to the random forest algorithm, achieving a comprehensive evaluation of the regional overall level of wind erosion events. The results demonstrate that the mean threshold wind velocity value in the study area is 4.29 m/s, displaying a decreasing pattern with higher values in the west and lower values in the east. The mean occurrence probability of the wind erosion value is 7.92 %, with regions exceeding 12 % basically located in the central and eastern parts of the Hunshandake Sandy Land, which means that the total annual cumulative time of wind erosion in these areas is expected to approach 1.5 months. This study can contribute to the development of a systematic assessment framework of wind erosion potential risks at the regional scale. It will provide crucial information and new insights for wind erosion process research, thereby offering a theoretical basis and technical reference for a full understanding of land desertification evolution patterns. [ABSTRACT FROM AUTHOR]

• Parent material exerts a significant influence on the soil texture and pH. • Parent material affects the soil water-holding capacity by affecting the soil texture. • Quartz sandstone soil exhibits the lowest water-holding capacity. • Argillaceous limestone soil exhibits the highest water-holding capacity. • Argillaceous limestone soil exhibits the lowest erosion resistance. The parent materials play an important role in soil hydrologic properties. However, in subtropical hilly areas with complex geological conditions, it appears that there is a lack of full understanding about the effect of parent material on soil water-holding and erosion resistance, which can be helpful for agricultural production and conservation of soil and water. In this study, five red soils developed from shale (Ds), quartz sandstone (Dqs), argillaceous nodular limestone (Danl), argillaceous limestone (Dal), and limestone conglomerate (Dlc) in subtropical China were selected. Soil properties, soil water-retention curves (SWRCs), water-stable aggregate fractions, and soil erodibility factor (K) were tested and calculated. The results showed that there are significant differences in soil texture among soils developed from different parent materials, soils with higher clay content have stronger water-holding capacity, and the average water-holding capacity of the five soils followed the order Dal > Danl > Ds > Dlc > Dqs. Furthermore, the erosion resistance of soil is closely related to the clay content and the stability of soil aggregates, and the sequence of average K -value among the five soil types is as follows: Danl > Dal > Dlc > Ds > Dqs. Partial least squares regression revealed that the stability of aggregates has a more significant influence on soil erodibility than the clay content. Therefore, soils with higher mean weight diameter (MWD) and geometric mean diameter (GMD) are more resistance to erosion. This paper evaluated the distinctions in basic properties and hydraulic properties between different parent materials under similar climatic conditions, elevations and vegetation in subtropical hilly area of Southern China, which can serve as a scientific foundation for soil and water conservation in the environments characterized by complex geological conditions. [ABSTRACT FROM AUTHOR]

• Hillslope erosion dynamic model integrating vegetation effect was established. • Unified baseline parameters were obtained across different land uses. • Effect of vegetation on soil detachment and sediment transport was revealed. • Contribution rates of vegetation to sediment reduction along slopes were quantified. Developing a process-based soil erosion model that comprehensively considers the effects of vegetation is complex but crucial for evaluating sediment reduction during vegetation restoration. Current understanding of the effect of vegetation on sediment reduction along hillslopes across different land uses is limited. In this paper, we developed a dynamic model of hillslope erosion that integrates the effects of vegetation on soil detachability and hydrodynamics (VED) based on the feedback mechanism between soil detachment and sediment transport. The VED was calibrated and validated with runoff plot data for woodland, grassland, and farmland in the Wuding, Yan, Jing and Wei Rivers of the Loess Plateau in China. Unified baseline parameters and decay coefficients of vegetation were obtained. The model validation results indicated that the coefficient of determination, Nash–Sutcliffe simulation efficiency and relative error ranged from 0.59 to 0.99, 0.56 to 0.90, and −45.99 % to 46.36 %, respectively. The decay coefficients for soil detachment capacity (Φ), sediment transport capacity (T c), and the sediment reduction effect of vegetation exhibited the following order: woodland > grassland > farmland. Compared with VED, existing process-based soil erosion models failed to effectively characterize the influence of vegetation on Φ and T c on the Loess Plateau, with differences of several orders of magnitude. The individual contributions of runoff, soil detachability, and hydrodynamics with vegetation impact on sediment yield were quantified by VED. The contribution rates of vegetation to sediment reduction decreased gradually with increasing slope length because the soil detachment capacity of bare slopes exceeded that of vegetated slopes, resulting in a faster increase in sediment yield. The contribution rates of vegetation to sediment reduction for woodland, grassland, and farmland with 20 %–60 % vegetation covers were 66.75 %–99.95 %, 57.43 %–99.63 %, and 27.91 %–88.63 % in the boundary conditions of this study, respectively. The results reveal the potential for integrating VED into other distributed watershed hydrological and sediment models to assess the effects of vegetation restoration on sediment reduction at a watershed scale. [ABSTRACT FROM AUTHOR]

• Mediterranean inlands face marginalization due to factors stemming from natural constraints. • Abandonment was led by field agricultural use, slope and fragmentation. • Both abandonment and recovery activities are ongoing in Gennargentu-Mandrolisai. • Grasslands were the most recovered areas. • Encouraging coordination among farmers could help mitigate the marginalization impacts. Farmland abandonment is a growing issue in many mountainous regions worldwide, particularly in the Mediterranean basin. The central region of Gennargentu-Mandrolisai in Sardinia (Italy) is particularly susceptible to this trend due to its distinctive topography, its remote localisation and the distance from the primary urban centres of the region. In fact, this region was traditionally suited for agro-silvopastoral systems, but it was included in the national strategy for inland areas mainly because of the demographic decline and land abandonment. This paper aims to identify the main drivers of rural marginalisation, abandonment and de-anthropisation by combining qualitative and quantitative spatial data. Qualitative data were collected from 30 farmers' interviews targeting young, dynamic, innovative farmers in order to identify possible triggers for maintaining agricultural activities. A diachronic analysis of land use from Corine Land Cover maps at five different dates over thirty years (1990, 2000, 2006, 2012 and 2018) was used to understand the main land use changes. The analysis of the surveyed farmland (1602 ha) showed that 21 % of the area was abandoned in the last three decades, and 15 % of abandoned land was recovered as farmland. The drivers of marginalisation identified by the farmers were analysed by a logistic regression model, which revealed that field management was influenced by 'crop type', 'slope' and 'road distance from the farm buildings'. The interactions that arose between the natural characteristics and the traditional organisational system contributed to non-competitiveness and abandonment of farms in Gennargentu-Mandrolisai. The present data allow us to propose hypotheses on how agricultural activities could be shaped and how some drivers of marginality could be overcome thanks to the presence and the active work of many young farmers who are willing to further improve agriculture. [ABSTRACT FROM AUTHOR]

• Epirogeny maintained per-humid climate for laterization on Adamaoua, West Africa. • Three stepped lateritic landsurfaces differentiated on granitoids of Adamaoua. • Eocene and Mid-Miocene volcanisms bound periods of lateritic surfaces formation. • Lateritic remains from etch-plain type Paleosurface in landsurfaces regolith. • Pediplain formed downslope the first two etch-plain type landsurfaces. The aim of this paper is to describe and discuss the laterization pattern and the structuration mode of land-surfaces formed over the Pan-African granitic basement of Adamaoua highland. Paleocene to mid-Eocene epeirogeny compartmentalized the regional topography of Adamaoua on which lateritic landsurfaces have been formed over granitoids of comparable geochemistry. Regional scale geomorphological observations and petro-geochemical characterization of lateritic duricrusted regolith allow to distinguish three distinct lateritic landsurfaces, which are compared to lateritic surfaces from West Africa. Regolith of the upper and middle landsurfaces incorporate composite lateritic duricrusts including old bauxites and ferricretes, which are petrological heritages from former regolith of etch-plain type Paleogene African Surface. On Pan-African granitic basement of Adamaoua, the upper and middle landsurfaces formed on granitoids before mid-Miocene basaltic-andesitic outpourings that locally cover them, while the lower landsurface also formed on grantic rocks has been mostly shaped over late Neogene. The geochemical compositions of lateritic duricrusts of upper and middle landsurfaces are clearly distributed between aluminous, ferruginous and kaolinite poles that typifies lateritic regolith of the bauxitic and (Fe-rich) intermediate etch-plains surfaces similarly as lateritic regolith of the Paleogene West-African sequence. Geochemical compositions of lateritic regolith on lower landsurface are mostly distributed between silica, kaolinite and iron, suggesting that more or less evolved or duricrusted horizons have been exposed by differential erosion of this landsurface. Lateritic regoliths of the three landsurfaces are also typified and differentiated by their index of laterization (IOL) and fractionation patterns of some trace (Cr, V, Zr, Ti, Nb, Th, Y, Ta, Ga) and rare earth elements (HREE, Eu/Eu*, (Gd/Yb) N). Though Neogene volcanic epirogenic uplift effects on landscape cannot be totally excluded, erosion and down-wasting of Paleogene landscape mostly evolved to a degraded lateritic etch-plain and late formation of a lower pediplain on Pan-African basement of Adamaoua highland under long-lasting per-humid climatic conditions over Cenozoic. [ABSTRACT FROM AUTHOR]

• Obvious segmentation phenomenon of wind speed profiles of plant covered surfaces. • Predicting models of key physical variations of wind velocity profiles. • A new relationship between drag coefficient and lateral cover. Implementing vegetation is the preferred measure for controlling soil wind erosion. The physical variations in the wind velocity profile, such as the friction wind velocity (u *), aerodynamic roughness (z 0), zero-plane displacement (d) and drag coefficient (C d), are key to understanding soil wind erosion on vegetation-covered surfaces. However, the lack of systematic and in-depth research in the literature has led to significant controversy and uncertainty. Based on the wind tunnel data of wind velocities at 18 different heights near the ground surface for four plant heights (H = 5, 10, 15, and 20 cm) and densities (d s = 27, 46, 97, and 193 N/m2) and six free stream velocity (u ∞ = 6, 8, 10, 12, 14, and 16 m/s) scenarios, the relationships among u * , z 0 , d , the parameters of u ∞ and the vegetation structural characteristics, including the plant height (H), density (d s), and lateral cover (λ), are investigated in this paper. The conclusions are as follows: (1) The near-surface wind velocity profiles of the vegetation-covered surface can be divided into three segments with little variation in the wind velocity with height, a rapid increase in the wind velocity with height, and close to the free stream velocity. Their corresponding heights ranged from the surface to heights of 0.5 – 0.75 H , 0.5 – 0.75 H to 50 cm, and exceeding the height of 50 cm, respectively. (2) The zero-plane displacement increased with the plant height and density but decreased with the free stream velocity. The relationship between them can be expressed by Eq. (5). (3) The friction wind velocity of the vegetation-covered surface increased with the plant height, density, and free stream velocity. The relationship between them can be expressed by Eq. (6). The drag coefficient increased rapidly at first and then slowly decreased with increasing lateral cover, which satisfied the equation C d = 0.00155 + 0.0111 λ /(λ + 0.124). (4) The aerodynamic roughness increased with the plant height and density but decreased with the free stream velocity. The aerodynamic roughness of the vegetation-covered surface under different free stream velocities and lateral cover conditions can be expressed by Eq. (8). The study results are a basis for the modeling of the dynamics of wind erosion on vegetation-covered surfaces. [ABSTRACT FROM AUTHOR]

• Recurrent fire leads to degraded rainforest (DRf) and herbaceous-shrubby (HS). • Ksat and 6 years of rainfall-soil suction interactions are analyzed. • HS provide shallow soil saturation even during long dry periods. • Fire decreases Ksat in topsoil and it increases soil suction in depth at HS. • Post-fire soil changes tend to favor rapid suction loss in the unsatured zone. The role of fire in vegetation-soil–water interactions and its implications for soil stability and slope failures is poorly documented in humid tropical regions. This paper focuses on the relationships between vegetation change through recurrent fire and its effects on hydraulic conductivity and soil suction. Two monitoring sites were chosen on steep slopes in the mountainous domain of the Atlantic rainforest: the first is representative of degraded secondary rainforest (DRf) 25–30 years after slash and burn agriculture; the other represents herbaceous-shrubby vegetation (HS) resulting from wildfires in short-time intervals (<5 years). Two fires had previously occurred on the HS slope, one in December 2014 and the other in September 2019. Continuous records of rainfall and soil suction at depths of 10, 20, 50, 100, 150, and 220 cm provided a 6-year data collection from January 2015 to December 2020. Hydraulic conductivity (Ksat) field tests were conducted around the two monitoring sites before and after the September 2019 fire. The main results include: a) soil suction in the topsoil of both vegetation covers follow the rainfall inputs with high values of Ksat (DRf = 195 mm/h; HS = 203 mm/h); b) while quick rainfall-suction responses prevail within the DRf soil profile, soil suction at HS maintains a mean suction value around -27 kPa below 100 cm deep; c) field observations attest to the occurrence of hydrophobicity after the 2019 fire; d) Ksat tests just after this fire indicated a decreasing mean value from 203 mm/h to 46 mm/h; and e) by the end of the dry season after fire, there is a delayed increase in soil suction reaching -143 kPa at a depth of 100 cm and in smaller proportions at 220 cm deep. These results indicate that post-fire soil changes tend to favor the sudden loss of soil stability and slope failure during extreme rainfall events. [ABSTRACT FROM AUTHOR]

[Display omitted] • An overview of progress in aeolian landform dynamics utilizing CFD are reviewed. • Turbulence and particle motion modeling techniques promote sand transport simulation. • Key factors of simulation are wind regimes, surface roughness and bedform morphology. • CFD has advantages in controlled, accessible, visualized, and detailed simulation. • Three topics are proposed for future CFD researches on aeolian landforms dynamics. Relationships and feedback between airflow dynamics, sand transport and underlying surface characteristics play significant roles in the formation and evolution of aeolian landforms. Studies that apply Computational Fluid Dynamics (CFD) modeling have increasingly provided insights into the influence of wind dynamics and characteristics of wind-blown sand. However, there is a lack of systematic review on modeling airflow and sand transport over aeolian landforms. This paper reviews 105 relevant CFD studies from the literature up to 2023 and summarizes methods of modeling airflow and sand transport. Additionally, it reviews their implementations of these methods and findings on how wind regimes and underlying surface characteristics, including surface roughness conditions and bedform morphology, affect wind dynamics and the behavior of wind-blown sand. This review aims to provide a comprehensive review of CFD modeling methods and their application to better understand the utilization of CFD simulations of aeolian landforms. CFD approach provides a valuable alternative to study related filed in a controlled, accessible, visualized, and detailed manner. We conclude this review by recommending three topics for future research to improve the accuracy of modeling and promote applications of CFD to aeolian landforms, i.e., modeling critical and comprehensive turbulent flow, developing robust and accurate models of particle motion, and investigating the effects of vegetation and boundary layers. [ABSTRACT FROM AUTHOR]

• Undrained shear strength (s u) of fine-grained soil got with pocket penetrometer (PP). • Logarithm s u versus liquidity index (I L) relationship non-linear over plastic range. • Dissimilar experimental s u – I L relationships for different fine-grained soils. • PP s u similar to mobilized s u in unconfined compression (UC) test. • For unsaturated sample, unconsolidated-undrained triaxial s u greater than UC s u. This article presents an appraisal of the recently published research paper in the Catena Journal titled "Practical transitions among undrained shear strengths of remolded samples from pocket penetrometer tests and other laboratory tests". This paper investigated correlations on undrained shear strength (s u) with liquidity index (I L) among pocket (soil) penetrometer (PP), fall-cone, laboratory vane, unconfined compression (UC), and unconsolidated-undrained triaxial compression test methods for 10 fine-grained soils investigated. Some differences between the mobilized s u for testing of identically prepared samples of a given soil using different strength measurement approaches could be expected. However, the data plots presented in the original paper indicate that, depending on the I L , significantly different s u values can be mobilized among several of these strength tests for a given water content — an aspect that merits critical examination. In this discussion of said paper, several observations are presented on various shortcomings in the adopted experimental methods, as reported in the original paper, and in the s u – I L data analyses presented for the different strength tests investigated. Also, with the spring-operated piston of the PP device usually calibrated (by the manufacturer) using correlation studies with UC strength data, the good agreement obtained for the Authors' PP and UC s u – I L correlations would be expected. [ABSTRACT FROM AUTHOR]

[Display omitted] • The thematic have been studied by increasing the extension and occurrence of fires. • A total of 530 papers related to fire are published from 1984 to 2020. • Publication rates have particularly increased since 2007. • Scientists from USA and Spain have made the most significant contributions. • More specific research needs to be done on how fires affect soil mineralogy and microbiology. As wildfires have increased and become more frequent in recent years, researchers area focusing on how wildfires affect ecosystem resilience, which has serious implications for the recovery and protection of native forests and plantations. Most physicochemical and biological soil properties, including soil surface mineralogical composition, can be severely impacted by fires. However, no attempt has been made from a bibliometric point of view to provide a comprehensive picture of the research status on fire effects in mineralogy and nutrient stocks. Using the VOSviewer software, this study aims to evaluate fire effects on mineralogy and nutrients (FMN), the thematic evolution and determine the most relevant trends based on the intellectual structure of the knowledge built up in this research field. The methodology is divided into two stages: (i) Data Collection, and (ii) Bibliometric Analysis and Data Mining (Performance Analysis and Science Mapping). A detailed bibliometric analysis was performed on 530 Web of Science (WOS) articles indexes from1984 to 2020. Overall, the results show that Forest Ecology and Management is the leading journal in the field. The top three countries hosting core research centers for this topic are the United States, Spain, and France. Certini G. was the author with more citations (1395) in one paper and Johnson, D. had the most published papers (19) with a total of 549 citations. Currently, the hotspots of fire issues mainly include soil nutrients (e.g. nitrogen, phosphorus, carbon, and calcium); in addition to the selected keywords, wildfires co-occur more frequently with disturbances and terms such as soils, water quality, boreal forests , and stream. In conclusion, 530 articles written by 1822 authors and their research displayed in 211 journals from universities and research centers in 60 countries demonstrate the growing interest in the field. [ABSTRACT FROM AUTHOR]

[Display omitted] • NDVI shows an overall increasing trend from 2000 to 2020. • The Hexi region shows a warming and wetting trend. • Extreme precipitation is more important for NDVI. • The lag effect of NDVI on climate extremes varies by indicators and spaces. Climate extremes significantly affects vegetation dynamics, and understanding the relationship between dryland vegetation and climate extremes is crucial for regional ecological security and disaster warning. According to meteorological and satellite remote sensing data, the paper analyses the dynamics of normalized difference vegetation index (NDVI) and climate extremes in the Hexi region from 2000 to 2020 using Theil-Sen Median, Mann-Kendall and linear regression methods; the relationship between climate extremes and vegetation dynamics is revealed using Pearson correlation and boosted regression trees (BRT) models. On this basis, the time-lag effect of NDVI in response to climate extremes was further investigated. The results show that the NDVI in the Hexi region increased from 2000 to 2020, with significant greening (67.72 %) and a small amount of degradation concentrated in the desert in the northwest and the oasis in the southeast. The correlation between climate extremes indicators and NDVI shows a large spatial heterogeneity, with extreme precipitation showing a high importance for all regions except oasis. NDVI has no lag or 1 month lag for extreme temperature, no lag for max 1-day precipitation amount (Rx1day) for areas other than mountainous areas, and a 3-month lag for max 5-day precipitation amount (Rx5day) for extensive areas. The results of this study could serve as a reference for the study of the relationship between vegetation dynamics and climate extremes in arid and semi-arid regions, and provide a theoretical basis for the establishment of scientific and reasonable strategies for regional vegetation restoration and conservation. [ABSTRACT FROM AUTHOR]

• Lake evolution of Sumxi Co has been reconstructed from lacustrine carbonate isotopes. • Hydrological conditions were mainly dominated by regional precipitation on the northwestern QTP. • Millennial hydroclimate events were responding to globally cooling events and solar irradiance. Climatic and hydrological changes on the Qinghai-Tibetan Plateau (QTP) are controlled by the Asian summer monsoon and the mid-latitude westerlies, which directly affect a large population in Asia. However, the millennial temporal and spatial patterns of Holocene hydroclimate variations on the QTP remain unclear due to the lack of high-quality paleoclimatic records. This paper examines high-resolution stable oxygen and carbon isotopes of authigenic carbonate (δ18O carb and δ13C carb) covering the past 5,000 years taken from Sumxi Co, a hydrologically closed lake lies outside the direct influence of the large ice caps on the northwestern QTP. The hydrological environment of Sumxi Co inferred from the covariance between δ18O carb and δ13C carb values was unstable during the middle to late Holocene, with abrupt increases in lake-levels during the 5.0–4.0 cal ka BP, 3.2–3.1 cal ka BP, 1.8–1.3 cal ka BP, and 0.7 cal ka BP to present. Past millennial hydrological fluctuations coincide temporally with the occurrences of glacier advances on the northwestern QTP, implying increased regional moisture and precipitation during cold periods in the region. The 'cold and wet' hydroclimatic pattern is comparable in other records to the arid areas of central Asia dominated by westerlies before the current anthropogenic warming. The four millennial-scale humid events are synchronous with reduced solar irradiance within dating errors, supporting the hypotheses that the regional pattern of hydroclimatic evolution in arid central Asia responds dominantly and directly to changes in solar activity. This external forcing may be amplified by North Atlantic cooling events and southward shifts of the intertropical convergence, which have further modulated the position of mid-latitude westerlies and the strength of the Indian summer monsoon. [ABSTRACT FROM AUTHOR]

• Channel dynamics of pseudomeandering rivers is poorly known. • The study river reacted very rapidly to sediment supply changes. • Deforestation resulted in an increase of sediment supply and in a braided channel. • Reforestation and gravel mining caused river incision and a low sinuosity channel. • Post mining sediment supply increase was a key factor in shaping channel morphology. Typically, pseudomeandering rivers are gravel-bed streams considered unstable and prone to turning into braided or meandering channels under the effect of external forcings. Channel changes of pseudomeandering rivers have not been investigated in detail so far. This paper analyses the response of a pseudomeandering river (the Cecina River in western central Italy) to variations of sediment supply resulting from streambed material mining and land use change throughout the last two centuries. Old maps and 11 sets of aerial images from 1954 to the present of four representative sites were used to measure the variation through time of bankfull width and channel sinuosity. The changes in the number of bends, chute channels, bank erosion, bend extension, migration and retraction were recorded and the main processes which favoured pseudomeandering river channel changes were investigated. The old maps indicate that in the first half of the XIX century, the study river had probably a braided morphology in response to the increase in sediment supply following the liberalization of deforestation. From the beginning of the XX century to the present, the river had a predominantly single thread, pseudomeandering morphology which did not change during about 20 years of intense gravel mining (the 1960s – mid-1980s) when the main response of the river was channel incision and narrowing. A few years after bed material extraction stopped the river started to widen, to increase channel sinuosity and consolidate its pseudomeandering morphology. The study confirms that marked variations in sediment supply are more effective than floods in triggering river channel changes. The study also shows that the pseudomeandering configuration is less unstable than previously highlighted in other scientific works. [ABSTRACT FROM AUTHOR]

• Different paleosol types record past climate and vegetation change in the Lanzhou Basin, Gansu. • Persistent arid to semi-arid climate from Eocene to Miocene was interrupted by warm-humid spikes. • Lanzhou basin paleosols recorded a variety of Cenozoic global paleoclimatic events. • The rain shadow from Tibetan Plateau uplift maintained arid to subhumid eolian deposition. Global cooling over the past 45 million years has been well established from deep sea isotopic records, and one explanation has been the cooling effect of uplift of the Tibetan Plateau. Other explanations for cooling are initiation of circum-Antarctic circulation, and carbon sequestration by newly evolved grasslands. The Lanzhou Basin is located at the intersection of the Tibetan Plateau, eastern monsoon region, and northwestern arid region of China, so well placed to evaluate Tibetan Plateau effects. This paper infers paleoclimatic changes from a long sequence of Cenozoic paleosols within the Xiliugou, Yehucheng and Xianshuihe Formations, in the Lanzhou Basin of Gansu. Eleven distinct kinds of paleosols (pedotypes) were recognized in the field from root traces, soil horizons and soil structures. These pedotypes were then intepreted as soils by R-mode factor analysis and molecular weathering ratios of major element geochemical composition. Supporting data from compaction-corrected depth to carbonate in the paleosols show that paleoclimate was persistently arid to semi-arid from the middle Eocene to the middle Miocene, but interrupted by transient climatic warm-wet events, which correlate with marine oxygen-isotopic events and large igneous province basaltic eruptions. At 42, 34, 22, 18, 17 and 16 Ma, spikes of mean annual temperature (MAT) and mean annual precipitation (MAP) are evident from the paleosols, at times also recognized in global marine isotopic and stomatal index carbon dioxide records. At 37, 33 and 23 Ma, low MAP and MAT estimated from paleosols of the Lanzhou Basin coincide with glacial advances, and marine oxygen isotopic spikes and low CO 2. Paleosols of the Lanzhou Basin record global paleoclimate events during the middle Eocene to the middle Miocene, rather than variation in Tibetan Plateau uplift. The rain shadow from Tibetan Plateau maintained generally arid to subhumid eolian deposition in Gansu for the past 50 million years. [ABSTRACT FROM AUTHOR]

[Display omitted] • AHA addition can enhance the adsorption capacity of soil phosphorus. • AHA decreases phosphorus loss under freeze-thaw condition, and the longer the freeze-thaw time, the better the effect. • Alkaline conditions and high ionic strength promote the migration of soil phosphorus through electrostatic repulsion. • Two-site model results fit well with breakthrough experimental data. The problem of soil nutrient loss has become increasingly serious in recent years, and the problem of soil "thinning" has led to a gradual decrease in the soil's ability to fix phosphorus (P). In order to effectively alleviate the loss of soil nutrients and improve the ability of soil to fix phosphorus, artificial humic acid (AHA) is a promising material. Therefore, this paper focuses on the effect of AHA addition on the transport behavior of P in soil. Column experiments were designed considering four environmental influences (AHA addition, freeze-thaw cycles, background pH and ionic strength) and two types of soils (black soil and saline soil). In order to clarify the mechanism of its migration behavior, we used characterization methods, Density functional theory (DFT) calculations and the two-site nonequilibrium transport model (TSM) models. The results showed that AHA effectively enhanced the P fixation ability in the soil. Specifically, with the increase of AHA concentration, the soil formed an envelope complex and further enhanced the absorption and fixation ability of soil P through complexation and electrostatic action. We found an interesting phenomenon that AHA can enhance the adsorption of P in soil as the number of freeze-thaw days increased, contrary to our initial hypothesis that freezing and thawing would lead to a decrease in the ability of AHA-added soils to fix P. At lower pH, the protonation reaction of functional groups on the surface of AHA molecules led to the neutralization of OH– which in turn enhanced the adsorption of P in soil. The lower ionic strength weakened the electronegativity of the soil and enhanced the fixation of P in soil. Meanwhile, the TSM could better simulate the P transport behavior under the above-mentioned condition. This study elucidated the transport behavior of P in black and saline soils with the introduction of AHA, which could effectively clarify the environmental risk caused by P loss and improve the ecological benefits of AHA. [ABSTRACT FROM AUTHOR]

• Amount & composition of stored sediment in rain-impacted flows affect erosion. • Amount & composition of stored sediment varies until the steady state occurs. • Compositions of stored and discharge sediment differ from each other. • Compositions of soil and sediment discharge is the same at the steady state. Many experiments on erosion by rainfall involve applying artificial rainfall on inclined planar soil surfaces. When sediment is discharged by rain-impacted flows, the transport of silt and sand-sized particles is dominated by raindrop-driven transport processes such as raindrop-induced saltation and rolling. Raindrop-induced saltation is a process which stores detached material on the soil surface as it transports detached material downstream. The amount stored increases with time until it reaches a steady state. If all particles transported downstream travel at the same rate, then the composition of the stored material is the same as that of the original soil. However, particles transported by raindrop-induced saltation travel at rates that vary with their size a density. This results in the composition of the sediment discharged to vary with time until the steady state is reached. In this paper, a qualitative mathematical model is used to demonstrate how the composition of the stored material varies with slope length, rainfall intensity, flow depth and the particle sizes being transported. The results produced by the model demonstrate that fine material is enriched at the expense of coarse material in the sediment discharge while being depleted in the stored material until the steady state is reached. The buildup of detained material on the soil surface also influences the amount of soil material discharge as time progresses during an erosion event. Consequently, the erosion rate will vary with time until the steady state is reached. Many experiments involve applying rain for a fixed time and consider the average erosion rate as the independent variable is regression analyses to determine the effect of factors such rainfall intensity, slope length, slope gradient and soil type on erosion. The inclusion of erosion when the steady state does not exist means that the results of these experiments have limited values beyond the experimental conditions used in the experiment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soils under anthropic uses showed more remarkable changes in soil properties with rainfall seasonality than soils under natural páramo. • Land-use change from natural vegetation to potato and onion crops followed by fallow reduces soil organic matter and water content and increases bulk density. • Land-use change could impair the ability of páramo catchments for streamflow buffering and this could increase surface runoff and reduce base flow. High-Andean páramos deliver essential ecosystem hydrological services from a combination of soil, vegetation, and climate characteristics, particularly in their natural state. However, agricultural activities considerably affect the páramo's ability to store, regulate, and supply water. Although there is information on the effect of potato crops (Solanum tuberosum) on páramo soils' properties, the effect of spring onion (Allium fistulosum) crops has been studied less. In addition, dry páramos are underrepresented in existent páramoś research. This study assessed the effect of rainfall seasonality (RS) and land-use change (transformation from páramo vegetation to crops) on soil hydrophysical properties associated with hydrological services (streamflow buffering) in a dry páramo in the Eastern range in Colombia. Six dominant land uses were studied: natural páramo vegetation (low slope, steep slope, and dense shrublands) and anthropic use (onion crops, potato crops, and fallow). An in-depth random stratified discrete design (0–5, 10–15, and 20–25 cm) was used to collect samples for analysis of soil organic matter (SOM), bulk density (BD), pH, and electrical conductivity (EC). Hydrophysical properties were measured at the soil surface: water retention capacity (WRC), structural stability (SS), and infiltration capacity (IC). Soils under anthropic uses showed more remarkable changes in soil properties with RS than soils under natural páramo. On the other hand, land-use change from natural vegetation to potato and onion crops followed by fallow leads to a reduction in SOM (9.8 %) and an increase in BD (0.19 gcm−3), especially at the surface level. In addition, this leads to a loss of WRC (20 % at field capacity), an increase in unstable aggregates (13 %), water erosion, and a loss of IC (44 mmh−1). This paper demonstrates the impact of land use on soil hydrophysical properties that compromise the maintenance of hydrological services and contributes to a better understanding of the complexity of Andean páramos. [ABSTRACT FROM AUTHOR]

• A novel macroscale terrain factor proposed, enlarges terrain break of gully erosion. • Computer sight simulates the factor, different from slope, openness, and hillshade. • Uncertainty caused by resolution, direction number, look distance and skip radius. • Human vision finds the critical value for gully shoulder line on the loess plateau. • P-N terrain is linked with repose angle under the complexity of loess landform. As a type of terrain break, the gully shoulder line is of great significance to locate the scope of surface failure and soil erosion. Based on the knowledge of the terrain structure of loess gullies, this paper modeled sight lines to calculate the three-dimensional maximum elevation angle (3D MEA). Then, a critical MEA value of 35° was determined via human vision to extract negative terrain and shoulder lines considering unmanned aerial vehicle (UAV)- and light detection and ranging (lidar)-based digital elevation models (DEMs). In addition to the DEM resolution, the uncertainties caused by the direction number, look distance and skip radius of computer sight were further examined. It was suggested that the process should involve observing at least 12 directions to detect complete information on terrain breaks. The simulation process required a relatively large look distance to analyze global terrain changes because a small distance could limit sight within the local window. The skip radius could result in the process ignoring nearby abrupt changes in terrain, thus causing negative terrain to be misclassified as positive terrain near shoulder lines. The concept of wall morphology was introduced to attribute the critical value to the repose angle of loess gullies. Eventually, the MEA was compared with many other parameters. It could be concluded that the slope is limited to the local scale, while the MEA could combine local and global scales using a large look distance. The hillshade is limited to one viewing direction, but the 3D MEA is a comprehensive layered index from multiple directions. This study is a novel exploration of interdisciplinary hydraulic engineering and information technology. This approach reduces terrain breaks from three-dimensional space into a one-dimensional index and simplifies shoulder lines as a critical 3D MEA value related to loess material properties. This research could be adopted for soil and water conservation. [ABSTRACT FROM AUTHOR]

• Tree richness and mycorrhizal-symbionts effects on SOC, GRSP-C, Rh, Q 10, Hs and GHGs were studied. • High tree richness induced 16–126.6% higher SOC, TG-C, Rh, and in situ N 2 O flux. • AM dominant plots had 34–39% higher SOC and Rh than the ectomycorrhizal plots. • Richness and AM's effects in 0–1 m soils were more evident than 0–20 cm soils. • Richness directly improved stability, while richness-AM-decreased-CAZymes favoured storage accrual. • Six types of CAZymes of GHs, PLs, CEs, GTs, AAs and CBMs cooperatively worked in the regulation. Biodiversity loss and tree alternations often occurred in high-latitude Northern Hemisphere forests owing to climatic changes and human disturbance, while their effects on soil carbon sequestration remain unclear. In this paper, tree richness and arbuscular mycorrhizal (AM)-tree dominance experiments were settled in an experimental forest, and soil organic carbon (SOC) and glomalin-related soil protein carbon (Total, TG-C and easily extracted, EEG-C), stability (heterotrophic respiration, Rh, temperature sensitivity, Q 10 and humidity sensitivity, Hs), in situ soil CO 2 , CH 4 , N 2 O fluxes, and CAZymes activities from the microbial metagenome technique were measured to identify their impacts and underlying mechanism. Both analysis of variance (ANOVA) and linear regression found tree richness and AM tree loss accompanied by soil carbon sequestration loss of total SOC storage, their mycorrhizal components (TG-C) and Rh. In 0–20 cm soils, high tree richness quadrats had 16–126.6 % higher SOC, TG-C, Rh, and in situ N 2 O flux, while AM-dominated stands had 34–39 % higher SOC and Rh than the EcM-dominated stands. In the 1 m soil profile, the effect size from tree richness and AM trees were more evident than the 0–20 cm soils. Compared with the richness gradient, much significant differences occurred between AM- and EcM-dominated stands. Structural equation modeling found that tree richness directly improved C stability, while the SOC accrual from the tree richness enrichment and AM-tree dominance were indirectly achieved by their decreasing in multiple CAZymes activities. Of CAZymes, glycoside hydrolases, polysaccharide lyases, carbohydrate esterases, glycosyl transferases, auxiliary activities, and carbohydrate-binding modules cooperated in their regulation of the soil C accrual. Our findings support carbon sequestration via biodiversity conservation and proper forest management related to tree mycorrhizal symbionts. [ABSTRACT FROM AUTHOR]

• A proxy based on mass movements for assessing climate change was proposed. • The periodicity of mass movements conforms to the changing patterns of traditional climate proxies. • Climate change determines the spatial and temporal distribution of mass movements. The spatial and temporal distribution, as well as the formation and evolution of mass movements in the Qinghai-Tibet Plateau orogenic belt, have been extensively discussed. We gathered research papers focusing on the ages of Quaternary residual deposits associated with mass movements in the surrounding orogenic belts of the Qinghai-Tibet Plateau. A total of 172 large-scale typical deposits and their ages were analyzed to explore the primary driving mechanisms behind mass movements in the Qinghai-Tibet Plateau. As these deposits were collected from diverse geological environments and the ages primarily concentrated in the Late Pleistocene and Holocene periods, we categorized mass movements with ages younger than 140 ka into three distinct regional climate systems: the Indian Summer Monsoon, the East Asian Summer Monsoon, and the Westerlies. The relationship between the emergence of mass movements and climate change was thoroughly investigated. Our research indicates that mass movements can serve as a reliable proxy for indicating climate change. The cycles of mass movements are closely synchronized with the warm and cold alternations of regional climates, holding significant importance in reshaping the environmental evolutionary history. We propose that the extensive mass movements in the Qinghai-Tibet Plateau are primarily driven by periodic climate variations, although they may not exhibit a perfect one-to-one correspondence. [ABSTRACT FROM AUTHOR]

• A new vacuum saturation device for high-suction tensiometers was proposed. • The new device significantly improved the measured range of suction. • We analyzed the response characteristics of an insertion tensiometer. • The developmental stages of the tensiometer response curve were suggested. Tensiometers are devices that can be used to monitor suction variation in landslides and slopes. The soil suction that can be measured with a conventional tensiometer is limited to 85 ∼ 90 kPa due to water cavitation in the tensiometer. This low measurement range of suction may be insufficient to interpret and determine the hydraulic properties of unsaturated soil, especially in semihumid and semiarid climate regions. However, in most geotechnical engineering studies, conventional tensiometers are still utilized. Although several types of high-suction tensiometers have been developed in recent decades, high suction measurements are difficult in the field because the saturation procedures for these tensiometers are complex and time consuming. Hence, the development of a simple and rapid saturation method is necessary to support their application. The vacuum saturation technique is a simple and reliable technique for saturating the porous ceramic cup of a tensiometer. However, if a high-suction tensiometer is saturated via a vacuum syringe, the measurable maximum suction is usually<200 kPa, which limits the application of tensiometers in geotechnical engineering. In this paper, we proposed a simple saturation device and a saturation method (the vacuum cylinder saturation method, VCSM) to saturate high-suction tensiometers. Soil column experiments were conducted to investigate the advantages of the VCSM and the response characteristics of insertion tensiometers. The results indicated that high-suction tensiometers could easily and steadily measure a maximum suction of 350 kPa if saturated via the VCSM. The VCSM could effectively prevent or retard the occurrence of cavitation due to the high vacuum pressure and slow progress of water filling in the tensiometer shaft. In addition, the response curve of insertion tensiometers could be divided into three stages: installing disturbance stage, delayed response stage and equilibrium stage. The extent of the disturbance caused by insertion tensiometer installation is a key factor influencing the delayed response characteristics of the tensiometer response curve. This paper also provides greater insight into the saturation method of tensiometers and the application of insertion tensiometers. [ABSTRACT FROM AUTHOR]

• A new wetland mapping approach by combing hierarchical classification framework and optimal feature selection. • A coastal wetlands map of Yellow River Delta with 11 detailed wetland types. • Feature selection and separability analysis for accurately extraction of wetland. • Comprehensive analysis of uncertainty assessment for wetland classification. Wetlands play an important role in ecological health and sustainable development, their spatial distribution and explicit thematic information are crucial for developing management and conservation measures. The Yellow River Delta is an important coastal wetland reserve in China, its wetland types are complex and diverse, natural and artificial wetlands are easily confused, making refined classification more difficult. To address this challenge, we proposed a new wetland mapping approach by combing hierarchical classification framework (HCF) and optimal feature selection. First, inheritance-based multiscale segmentation was carried out to obtain object-oriented images, and decision tree classification was used for preliminarily identify wetland and non-wetland. Second, recursive feature elimination and cross-validation (RFECV) was used to select optimal features, which was then utilized for wetland refinement extraction by using random forest (RF) algorithm. The experiments were performed based on Sentinel-1, Sentinel-2 and NASADEM datasets. The results show that effective wetland classification features can be selected by using RFECV. The feature scores are as follows, red edge index > spectral features > vegetation/water body index > backscatter coefficient > topographic features > texture features > location feature > urban index > geometric feature. The overall accuracy and Kappa coefficient of the method in this paper are 92.36 % and 0.915, which are 14.62 % and 6.68 % higher than using only HCF or only RFECV. Compared with the GlobeLand30 and CAS_Wetlands datasets, the refinement of wetland mapping in this paper is higher. This study provides a new idea in methodological selection for wetland information extraction, and the resulting coastal wetland map can be used for sustainable management, ecological assessment and conservation of the Yellow River Delta. [ABSTRACT FROM AUTHOR]

• Homosoils are soils that share similar soil-forming factors. • Homosoils for our study area in Mali were found in Asia, Australia and the Americas. • Soil data were collected within homosoil areas globally. • Homosoils captured unique variability in the soil data. • New opportunity to populate areas with low soil data density. Many areas in the world suffer from relatively sparse soil data availability. This results in inefficient implementation of soil-related studies and inadequate recommendations for improving soil management strategies. Commonly, this problem is tackled by collecting new soil data to update legacy soil surveys. New soil data collection, however, is usually costly. In this paper, we demonstrate how to find homosoils with the objective of obtaining new soil data for a study area. Homosoils are soils that can be geographically distant but share similar soil-forming factors. We cluster the study area into homogenouse areas, and identify a homosoil to each area using distance metrics calculated in the character space spanned by the environmental covariates. In a case study in Mali, we found that large areas in India, Australia and America have similar soil-forming factors to the African Sahelian zone. We collected available soil data for these areas from the WoSIS database. Statistical analysis on the relationship between the homosoils corresponding to different areas of Mali and three soil properties (clay, sand, pH) displayed the unique variability captured by homosoils. The homosoils could explain 8% of the variation found in the soil datasets. There was a strong association between pH and homosoils corresponding to the semi-arid conditions and sedimentary parent material of Mali, whereas homosoils corresponding to other areas of Mali showed moderate association either with clay or sand. The location and spread of the group centroids were significantly different between depth-specific homosoils for the three soil properties. The approach developed in this paper shows the opportunity for identifying areas in the world with similar soils to populate areas with relatively low soil data density. The concept of homosoils is promising and we envision future applications such as transfer of soil models and agronomic experimental results between areas. [ABSTRACT FROM AUTHOR]

• The elasticity index is adopted to tradeoff the benefits and ecological effects of land consolidation. • Soil erosion of slopes with vegetation is tolerable under climate change. • Slopes below 63° are stable in 6 slope scenarios. • The slope of 53° with Caragana microphylla is the optimal combination scheme. Soil erosion and slope instability restrict the cutting slopes, especially the high and steep slopes of a construction site. It is difficult for present research of observation experiments and investigation to deal with these problems under climate change. Focusing on gully land consolidation in the loess plateau of China, this paper put forward a technical procedure to explore the optimal combination scheme of slope-cutting and vegetation-planting in future climate change. The technical procedure includes scenarios design, model calculation, and scheme optimization. This paper selected a back catchment in Yangjuangou catchment of Yan'an City as a case study and designed 54 combined scenarios consisting of 6 slopes, 3 types of vegetation (including bare land), and 3 climate scenarios. The soil erosion and slope stability under different scenarios were quantified using FLAC/Slope software and Water Erosion Prediction Project (WEPP) model. This paper innovatively designed elasticity indicators to trade off the increase of the flat land area formed by land consolidation and the resulting reduction in slope stability and increase in soil erosion. It is found that the slope of 53° with Caragana microphylla could be the optimal combination scheme considering flat land creating and the safety of slopes. The technical procedure and the resulting parameters could support gully land consolidation in related areas and be referenced by other construction projects. [ABSTRACT FROM AUTHOR]

• We provide the first detailed Relative Mean Sea-Level curve for the Northern Aegean. • We detected for the first time in this coastal area the Neolithic drowned landscapes. • Palaeogeographic reconstruction shows coastal progradation due to anthropic forcing. • Historical events appear to dominate the fate of the city over environmental factors. • We detected the impact of a tsunami in 544 AD in this part of the Thracian coast. This paper presents an integrated Geoarchaeological approach to Holocene landscape change and socio-environmental interaction around ancient Abdera, a Greek colony in Aegean Thrace. A combination of remote sensing, geomorphological mapping, sedimentary coring, and radiocarbon dating was used to build the first detailed Holocene sea-level curve in the Northern Aegean, and to reconstruct the palaeogeographic evolution around Abdera from the Neolithic onwards. The discussion of these results, alongside the available archaeo-historical data, sheds new light on the role of historical and environmental factors in the rise and eventual decline of Abdera, thereby challenging previous narratives. This study is the first to detect evidence of the Neolithic landscapes in this coastal area being submerged by marine transgression c. 5000 cal. BC. A lagoonal landscape developed from the Neolithic until Greek colonists settled in the area c. 654 BC. The results presented here suggest that the relocation of the city in the 4th century BC was not caused by the silting up of the bay but was due to historical events. The coastal progradation only became significant after 300 cal. BC and accelerated in the following centuries. Based on the data acquired, it is hypothesized that this was due to anthropogenic forcing of the sedimentary systems both at local and regional levels, caused by the development of the productive activities of the colony. The evidence presented here demonstrates that while Abdera retained good access to the sea, its decline in the 4th c. AD was certainly due to the gradual shift of the economic axis inland. By 400 cal. AD the coastline was very close to its current position. The results of this study also add to the catalogue of known tsunamis in the Northern Aegean, by providing new evidence of a tsunami on this section of the Thracian coast in 544 AD. [ABSTRACT FROM AUTHOR]

• NTDI (nonlinear trivariate drought index) performs better than single type drought indices for drought monitoring. • NTDI can effectively monitor the drought onset and duration. • NTDI shows good potential in the agricultural drought assessment. Due to the complexity of meteorological and hydrological conditions in a changing environment, previous drought indices for monitoring a specific drought type do not reflect the overall regional situation of water scarcity. Therefore, in order to obtain accurate and reliable drought monitoring, a more integrated drought index should be developed to identify drought events comprehensively. In this paper, a non-linear trivariate drought index (NTDI) was constructed based on the joint probability distribution of parametric copulas, combining precipitation (P), potential evapotranspiration (PET), and root zone soil moisture (SM) variables. Subsequently, it was respectively compared with four drought indices, SPEI, SSMI, SC-PDSI and TVDI, and cross-validated with actual recorded drought events and annual crop yield to evaluate its applicability in arid Central Asia (ACA). The results indicated that: (1) Frank copula (1-,3-month scale) and Gumbel copula (6-,12-month scale) were considered to be the best-fitted copula functions for constructing joint probability distributions in the ACA. (2) The NTDI integrated the P-PET and SM drought signals to sensitively capture drought onset and duration, reflecting the combined characteristics of meteorological and agricultural drought. (3) The drought information expressed by NTDI was generally consistent with recorded drought events, and the monitoring results are accurate. (4)The NTDI performed better in agricultural drought monitoring than other drought indices. This study provides a reliable multivariate composite indicator which is significant for drought monitoring, prevention and risk assessment in ACA. [ABSTRACT FROM AUTHOR]

• The natural variability of directly observed soil thermal conductivity was low. • Soil moisture can explain at least 50 % of soil thermal conductivity variability. • The effect of soil thermal conductivity on active layer thickness was insignificant. • Active layer thickness negatively correlates with soil moisture. The knowledge of soil thermal properties is important for determining how a soil will behave under changing climate conditions, especially in the sensitive environment of permafrost affected soils. This paper represents the first complex study of the interplay between the different parameters affecting soil thermal conductivity of soils in Antarctica. Antarctic Peninsula is currently the most rapidly warming region of the whole Antarctica, with predictions of this warming to continue in the upcoming decades. This study focuses on James Ross Island, where the Abernethy Flats automatic weather station is located in a lowland area with semi-arid climate. Air and ground temperature, soil heat flux and soil moisture during the thawing season were monitored on this site from 2015 to 2023. Moreover, two approaches to determining soil thermal conductivity were compared – laboratory measurements and calculation from field data. During this period, mean annual temperatures have increased dramatically for both air (from −6.9 °C in 2015/2016 to −3.8 °C in 2022/2023) and ground (from −6.5 °C to −3.2 °C), same as active layer thickness (from 68 cm to 95 cm). Average soil thermal conductivity for the thawing period reached values between 0.49 and 0.74 W/m.K−1 based on field data. Statistically significant relationships were found between the seasonal means of volumetric water content and several other parameters – soil thermal conductivity (r = 0.91), thawing degree days (r = −0.87) and active layer thickness (r = −0.88). Although wetter soils generally have a higher conductivity, the increase in temperature exhibits a much stronger control over the active layer thickening, also contributing to the overall drying of the upper part of the soil profile. [ABSTRACT FROM AUTHOR]

• Role of periglacial regions in mercury (Hg) cycling in the Antarctic coastal zone. • Spatial variability of Hg and MeHg concentrations in soil of ice-free areas. • Study confirms link between weathering of rocks and the Hg concentration in soil. • Presence of animals, e.g. penguins and seals, impacts the concentration of Hg in soil. • OM is a key factor affecting Hg distribution across Antarctic terrestrial ecosystems. The Antarctic plays a critical role in global mercury cycling as both a sink of Hg and, in response to rapid global warming, an emerging source of Hg through its release from thawing permafrost and recessing glaciers. At the present time, Antarctica and surrounding areas have little mercury contamination in comparison to other regions of the world. Understanding the sources and transformations of Hg in the Antarctic will be particularly important in predicting the role of a changing environment in the mercury cycle as emissions and global climate change. Study samples were collected at 12 stations, categorized into three groups based on the human or animal presence and flora. Sampling took place in December 2018 and January 2019, and soil and parent rock samples were collected and analyzed for total mercury concentration and its fractions using atomic absorption spectroscopy. Bedrock samples collected on the coast of Admiralty Bay were found to have low organic matter content, while soil samples from the west shore of the bay had a high variability of organic matter content, ranging from 3 % to 41 %. The concentration of total mercury in bedrock ranged from 2.1 ng/g to 15.0 ng/g, and in soil samples, the total mercury concentration ranged from 4.7 ng/g to 143.1 ng/g. This paper reviews current knowledge of Hg cycling in the Antarctic, including its sources, fate, and effects on the ecosystem. The implications of climate change for Hg cycling in the region are also discussed, highlighting the need for continued research to better understand the potential impacts of Hg contamination in the Antarctic. [ABSTRACT FROM AUTHOR]

• Landscape ecological vulnerability was assessed using bagging ANN-MLP and RF models. • B-MLP model was found best fit model for LEV assessment based on ROC curve, recall, precision, F1-score and accuracy. • Largest area under very high LEV was recorded in the southern part of the plains. • Rainfall, soil, vegetation and LULC were found influencing factors for LEV. • Plantation, embankments and geotextile technology are suggested to check erosion. Riverbank erosion is one of the most catastrophic hazards that renders floodplains vulnerable across the world vulnerable. It creates a significant negative impact on the environment and socio-economic life. This paper attempts to assess the landscape ecological vulnerability (LEV) to riverbank erosion in the Middle Brahmaputra floodplains of Assam, India by employing two machine learning models, namely artificial neural network-multilayer perceptron (ANN-MLP) and random forest (RF). Bagging ensembles were created for both ANN-MLP and RF (B-MLP and B-RF) to generate LEV zones. A total of eleven site-specific parameters were considered for the study. The receiver operating characteristic (ROC) based area under curve (AUC), accuracy, precision, recall and F1-score were used to validate the models and judge the models' performance. A sensitivity analysis was performed to deduce the most influential LEV parameters. The results revealed that B-MLP was the better-performing model compared to B-RF based on all five validation metrics. The largest area was found under very high vulnerability zone followed by very low, low, high and moderate vulnerability zones, based on both ensemble models. The western part of the floodplains was found to be more vulnerable than the eastern part. Moreover, the southern bank faced more vulnerability in comparison to the northern bank. The factors namely rainfall, soil type, vegetation and land /use land cover (LULC) influenced bank erosion vulnerability. This research provides evidence that the study area is under severe threat to riverbank erosion and urgently requires the implementation of effective mitigation measures. The study might benefit policymakers and local stakeholders to protect the floodplains from bank erosion and reduce vulnerability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Congeners of PCDD/Fs and DL-PCBs were examined in the sediments of Iznik lake. • PCB 118, PCB 105 and Hepta – Octa CDD/Fs are the dominant in the sediments. • Sediment close to industrial companies has the highest amount of pollutant. • Dioxin-like toxicity levels of sediments are higher than threshold of 0.85 pg TEQ/g. • Dioxin-like (PCDD/Fs and DL-PCBs) concentrations do not exceed the tolerable daily intake value. Iznik lake is the biggest lake in the Marmara region, which is the most industrialized and populated area of Türkiye. The lake is one of Türkiye's most important water supply areas and is located nearby the Iznik district of Bursa, with a population of about 45,000. It is being used for irrigation and fishery production, but not for drinking water. In this paper, the distribution, pollution source, and risk assessment of polychlorinated dibenzodioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in the surface sediments of Iznik lake and streams (both flowing to and flowing from the lake) were investigated. Six surface sediments collected from the lake and four surface sediments collected from the streams were analyzed in high-resolution gas chromatography-mass spectrometry (HR/GC–MS) system in accordance with EPA 1613 and EPA 1668 methods. The concentration ranges of the ∑PCDD/Fs is 21.4 pg/g d.w. (inside the lake (IZ-6)) – 54.5 pg/g d.w. (Gülayağı stream (IZ-8)) and ∑DL-PCBs is 13.5 pg/g d.w. (inside the lake (IZ-3)) – 46.3 pg/g d.w. (Olukdere (IZ-7)) respectively, with 2.68 pg TEQ/g d.w. on average. The results showed that the high chlorinated (Hepta – Octa CDD/Fs) dioxins/furans and pentachlorinated PCBs (PCB 118 and 105) are dominant in the sediments. A detailed assessment of PCDD/F congener profiles observed in the lake sediments speculated that the wastewater discharges to the lake could be the main pollution source, while other sources such as open burning activities, runoff of pesticide residues from agricultural areas and atmospheric deposition may have some contribution also. The health risk assessment performed for polluted sediment demonstrated that, in the worst case, dioxin-like (PCDD/Fs and DL-PCBs) concentration was a total intake of 0.37 pg TEQ/kg body weight/day, no exceeds the tolerable daily intake amount, where fish consumption accounts for nearly all of the total intake. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of data record length on environmental flow calculation is presented. • Method 7Q10 is the less sensitive to environmental flow calculations. • Trend analysis should be the starting point for calculation of environmental flows. • Environmental flows have a significant impact on water resource availability. • Environmental flows are the starting point for sustainable water management. The paper presents the analysis of problems regarding the calculation of EFs using selected hydrological methods. It was conducted in 14 catchments in the Vistula and Oder River basins in Poland. The Kostrzewa, Tennant, Q 90% , and 7Q10 methods were used for the analysis. The analysis showed a significant trend in the hydrological time series. The sensitivity of different applied methods to time series length was shown. High differences were observed between environmental flow (EF) values calculated for periods defined by break points. The hydrological drought and its impact for EFs were also observed for half years in the period. Finally, different values of water deficit characteristics were presented depending on the method used for EF calculation. [ABSTRACT FROM AUTHOR]

• The early attenuation of soil strength contributes to landslides caused by changes in pore water pressure. • Corrected the safety factor curve of cohesive soil slope superficial failure. • The potential sliding surface is closely related to the spatial variation of soil properties in the 'affected layer'. Slope failure is associated with changes in pore water pressure induced by rainfall, this paper further attempt to bridge knowledge gaps that exist in understanding the relationship between mechanism of rainfall-induced regional-scale widespread shallow landslides in cohesive soils and change in pore water pressure. We designed in situ slope experiments with pre-designed vertical profiles at the toe of the slope, and used pore water pressure, conductivity, and moisture content sensors to capture the changing characteristics of soil properties during slope failure. The experiment finds that failure occurred first where internal material was continuously taken out of the slope, even before the maximum static pore water pressure is reached. However, the slope remains stable when the pore water pressure near the failure surface reached the maximum static pore water pressure that could be provided by rainfall. Instead, slope failure during subsequent rainfall periods, even if the pore pressure is then lower. Meanwhile, the soluble minerals in the soil continuously dissolve and migrate, causing the electrical conductivity before slope failure is approximately 1.38 times that after failure, on average. Here, we estimate that the changes in soil properties caused by progressive water infiltration only may have decreased test slope stability by an average of approximately 33.0%. Therefore, we suggest that the early attenuation of soil strength caused by the gradual changes in soil properties makes a significant contribution to soil failure caused by pore water pressure. This was verified in the case of the 7.25 Tianshui group-occurring landslides. Finally, by using an automatic laser particle size analyzer, scanning electron microscope, X-ray diffraction, ion chromatography, and quadruple direct shear instrument to analogize the changes in soil properties exposed to different leaching environments on loess platform, we further show that the early attenuation soil strength is caused by deteriorate in soil properties in the processes of successive years of rainfall, where the content of cemented minerals tends to decrease, fine particles tend to be lost, and pore structure tends to take the form of single macro-pores, which are more likely distributed around mineral particles >10 μm. Our results provide a new perspective on the widespread shallow landslides caused by changes in pore water pressure in a region and their associated gradual deteriorations in soil properties. [ABSTRACT FROM AUTHOR]

• We proposed a novel OBIA-GEE method for mapping gully affected areas. • 50 features from Sentinel 2 imagery and AW3D 30 DEM are used in OBIA-GEE. • OBIA-GEE considers the complex dynamic spectral characteristics of gully. • OBIA-GEE achieved good performance and robustness in mapping gully affected areas. • This research can be expanded globally since freely available dataset and platform. Gullies pose a great threat to the sustainable development of agricultural production and the ecological environment. Accurate mapping of gully affected areas plays an important role in regional environmental monitoring and management. In this paper, an object-based image analysis method based on the Google Earth Engine (OBIA-GEE) is proposed for mapping gully affected areas by using Sentinel 2 imagery and AW3D30 DEM data. The method utilizes the simple non-iterative clustering (SNIC) algorithm to segment the top-five principal component images derived from Sentinel-2 surface reflectance images. Then, the random forest (RF) algorithm is used for feature importance analysis and gully affected area mapping. Finally, the gully affected area mapping results are further optimized by establishing terrain skeleton lines. The proposed method is applied to five study areas with different landform types on the Chinese Loess Plateau, and the results show that the method achieves good performance in mapping gully affected areas, with an overall accuracy (OA) of 86.44%, an F score (F1) of 0.84, a user's accuracy (UA) of 84.97%, and a producer's accuracy (PA) of 83.90%. Compared with the OA of the results of a previous study (OA was 78.8%), the accuracy of the gully affected area mapping results herein improved by 7.64%. The RF feature importance results and findings of different feature combination cases demonstrate that textural information, time series spectral information, and topographic factors are important for mapping gully affected areas. Object-based and pixel-based classification results are compared, and the performance of the OBIA-GEE method is better than that of the pixel-based RF method. In addition, the OBIA-GEE method is highly efficient, which provides the possibility of applying the proposed method in large-scale studies. This research is beneficial to studies related to monitoring gullies and managing soil erosion. [ABSTRACT FROM AUTHOR]

• Ensuring adequate uniformity of simulated rainfall is critical in rainfall simulator research. • Current methods for assessing uniformity are insufficient to understand spatial variability. • The CU sampling methodology employed greatly affects rainfall uniformity quantification. • CU should be used in conjunction with other descriptive uniformity assessments. Rainfall simulators have been used extensively for a variety of research applications. The uniformity and spatial distribution of simulated rainfall is an important metric to consider when conducting rainfall simulator experiments. Over the past 80 years, several methods of assessing rainfall distribution and uniformity over the plot surface below a rainfall simulator have been developed. However, the Christiansen Uniformity Coefficient (CU; Christiansen, 1942) is most frequently used. Here, we provide a critique of this established methodology and metric for quantifying rainfall distribution characteristics. Uniformity coefficients express the distribution of rainfall across the plot surface as a single percentage value. Therefore, if all collection beakers receive equal volumes of water during an experimental run, the rainfall simulator or irrigation system would be applying water with 100% uniformity. There are shortcomings with using a single percentage value to represent rainfall simulator rainfall distribution, especially over a larger plot surface, and CU is highly dependent on the sampling methodology employed. This paper assesses rainfall uniformity by conducting a series of controlled uniformity experiments and resampling different grid layouts of collection containers. Results demonstrate that the coarseness of the sampling methodology affects rainfall uniformity coefficient values. CU values of 45 – 51% were recorded under a dense (17 × 17) sampling grid layout, compared to CU values of 81% using a coarser (8 × 8) sampling methodology, despite being subjected to comparable rainfall events. This paper explores the sensitivity of CU to the resolution and spatial layout of the sampling methodology used and assesses whether the CU captures repeatability and localised variability of uniformity between experimental runs. A complementary statistical approach expressing variations in relation to their standard deviation from the mean is presented. Understanding how experimental setup (i.e. number, density, spatial configuration of collection containers) affects CU is critical when interpreting results from different rainfall simulator studies and an understanding of the factors which influence CU is critical to benchmark the results of uniformity testing across different rainfall simulator setups. [ABSTRACT FROM AUTHOR]

[Display omitted] • A gully erosion area affected by weathering-related process is focused. • Comprehensive dataset of granite chemical weathering is given. • Applicability of chemical weathering index is critically assessed. • Weathering index is quantitatively corelated to mechanical property. • Various aspects of mechanical property of granite regolith are considered. In most cases, chemical weathering reduces the strength and stability of granite regolith and increases its water sensitivity. When combined with external agents such as climate, these alterations facilitate geomorphological evolution, such as gully erosion in hilly regions. The lack of fundamental understanding about how gully erosion forms have led to an increasing trend of gully erosion in recent years. Because the weathering-controlled properties of granite regolith have a significant effect on gully development, it is vital to assess the chemical weathering degree. However, despite extensive studies on quantifying weathering degree using chemical weathering indices, less is known about how these parameters are correlated with the mechanical properties of granite regolith. To this end, a typical weathering profile is established for granite in Jiangmen, China. This paper investigates the chemical weathering of granite, evaluates the appropriateness of previous chemical weathering indices, and correlates them with the mechanical parameters of granite regolith. Several suitable indices, including CIA, Bases/Al 2 O 3 , Bases/R 2 O 3 , ba 1 , ba 3 , CIW, I mob , and PIA, are selected and correlated with the mechanical parameters. These indices apply well, with some scattering when they are correlated with the internal frictional angle of granite residual soil. This paper provides a comprehensive datset regarding the physical, mineralogical, petrographical, geochemical, and mechanical properties of granite regolith, and enhances the understanding of chemical weathering, especially its correlations with the mechanical properties of regolith. [ABSTRACT FROM AUTHOR]

• Even though check dams are full, they still control the debris flows. • The new model can quantitatively evaluate debris flow mitigation effect. • The check dams and afforestation play different roles in different stages. Check dams and afforestation are two common measures for debris-flow mitigation; however, there is a lack of methods allowing quantitative evaluation of check dam and afforestation effects on debris flow motion and deposition. Laogan Gully is an active debris-flow system with a large landslide on the right hillslope, currently representing the main source of debris flows in the catchment. Several debris flows have occurred since 1985 which led to the construction of check dams and the plantation of silver wattle (Acacia dealbata) trees between 1991 and 1993. These measures significantly reduced the volume of debris flows reaching downstream portions of the system. At the same time, large amounts of sediment were trapped on the gully bed and thereby increased the base level of the torrent, which again tended to stabilize the large landslide on the right hillslope. This paper analyzes sedimentation of debris-flow material on the gully bed and on the fan using 12 trial pits behind the check dams and 6 incised geological sections on the fan. The timing and extent of debris flow motion and deposition was reconstructed using scars and growth suppression events in the annual growth ring series of 306 Acacia trees trapped in the newly formed deposits. The gravitational potential energy of the sediment of the large landslide is calculated according to the change in the erosion base level behind the check dams. On the basis of these results, we constructed a semi-empirical vegetation coverage–landslide energy–debris flow volume model to quantitatively evaluate the effects of the check dams and afforestation on debris-flow mitigation. The model exhibited predictive capabilities for estimating the volume of debris flow generated by the reactivation of landslides. Check dams are found to play a major role in debris-flow mitigation in the early stages, whereas the Acacia trees play an increasingly important role once the check dams are filled. The partial resurgence of the landslide caused a sudden increase in the gravitational potential energy of the sediment source, which in turn affected the effectiveness of the debris-flow mitigation measures. [ABSTRACT FROM AUTHOR]

• Lime input significantly decreased topsoil exchangeable potassium (EK) content. • The initial EK and acidic degrees were the key factors of effect on EK decrease. • Liming enhances the excavate and uptake of subsoil EK by crop roots in Ultisol. • Soil Ca, Al, and initial EK jointly regulate the Ultisol K availability after liming. Potassium (K) is the most commonly neglected macronutrient in global change, especially in acidified areas. Lime is a typical management to eliminate soil acidification in agroecosystem soils; however, its impact on soil K dynamics remains inconsistent under different acidic environments. Here, we combine a meta-analysis based on 407 observations from 89 papers and a long-term experiment to investigate the effect and main driving factors of liming on soil K change. The meta-analysis showed that lime application significantly reduced topsoil exchangeable K (EK) content by an average of 4.8% globally. The decrease in topsoil EK content due to liming depended on various soil properties, crop types, fertilizer regimes, and experiment types. Boosted regression tree analysis showed that initial soil exchangeable K (IEK) and pH were the main factors affecting soil EK change under the lime application. The field experiment results further evidence that the decrease of soil EK after the lime application was mainly due to increased K uptake by the crop, and EK transformed to non-exchangeable K (NEK). The application of lime has a greater impact on reducing subsoil EK content at a higher IEK thresholds. Soil EK showed a significant negative relationship with exchangeable calcium (Ca) and a significant positive relationship with exchangeable aluminum (Al). Redundancy analysis revealed that K input (KI), IEK, lime, Ca, Al, pH, and exchangeable magnesium significantly affected the K in soil and crops. The partial least squares path model showed that lime application and IEK levels combined indirectly influence soil K (EK and NEK) by directly affecting soil Ca and Al, K uptake, and K balances. The findings highlight the importance of the lime effect on K management in globally adverse environmental agroecosystems and indicate the key role of initial soil EK levels and acidification degree for regulating crops to excavate the subsoil potassium when subjected to liming. [ABSTRACT FROM AUTHOR]

(a) Conceptual diagram showing three dominant at-a-station hydraulic geometries and bank properties in the Brahmaputra River. (b) Relation between disturbance, resistance threshold and recovery, and temporal variation of system states. The variabilities of LPI, threshold, bank erosion potential and balance between nature-to-engineered (BNE) solutions are also shown. (c) River freedom space concept and resilience-based management approach for a highly braided river system. [Display omitted] • Geomorphic stationarity concept is applied to the identify the local hydrologic nodes. • Energy expenditure gradient is better related to sand bar adjustments than conventional threshold exceedance. • The location probability concept is implemented to recognize the vulnerable reaches. • Balanced combination of nature-based and engineered solutions is required dynamic rivers like the Brahmaputra. The present paper utilizes the Google Earth Engine (GEE) cloud computing platform and hydro-morphological dataset to understand the complex process-form relationships of the highly braided Brahmaputra River, India. To identify dynamic gradients between low and high risk of geomorphic adjustment/change, an analytical approach is developed to track and quantify the spatial patterns of geomorphic adjustment. In order to address the dominant geomorphological adjustments, two processed-based novel indicators are developed- the Normalised Threshold Exceedance (NTE) considering the excess energy theory, and the Normalised Process Gradient (NPG) utilizing the gradient between hierarchical thresholds. The results show that in a highly braided river system, the sand bar adjustments prevail over other forms of morphological changes and is closely dependent on the process gradient between the hierarchical thresholds. Further, the scale of planform evolution is computed from the Location Probability Index (LPI), and the geomorphic stationarity concept is introduced for a large braided river. Finally, a multi-faceted resilience-based freedom space management approach is designed based on system state trajectory, LPI variability, proximity to thresholds, and in-channel landform configuration. [ABSTRACT FROM AUTHOR]

[Display omitted] • Droughts and floods are increasing worldwide. • Changes in soil moisture affect the soil microbiome. • Climate change affects the soil environment. • Changes in the soil environment affect crop production. • Drought and floods have a negative impact on agriculture. Climate change is progressing and is already visible to the naked eye around the world. Hydrological events associated with climate change, i.e. floods and droughts, have reached extreme levels in recent years. Researchers warn that these phenomena will continue to intensify. According to recent reports, the number of extreme weather events, including hydrological phenomena, has increased by 60% in Europe over the last three decades. Both water shortages and water surpluses affect the soil environment and its functions. This in turn has a direct impact on crops and agriculture. For example, in the US alone, droughts and floods were responsible for more than 70% of the decline in cereal yields in 2011 alone. However, the soil environment is a complex ecosystem that is not yet fully understood, making it difficult to predict the impact of climate change on its quality and functioning. In this paper, we discuss the effects of floods and droughts on the soil microbiome and the implications of these changes for agriculture. We suggest that changes in soil moisture are an important factor affecting crop growth and yield, which is of great importance for global food security. [ABSTRACT FROM AUTHOR]

• Rapid geomorphological evolution occurred in the erodible lithology and semiarid climate of southern Italy. • A deposition phase during the Little Ice Age (LIA) was the last global cold climatic phase. • Badland incision occurred during Mediaeval Warm Period and continued in stably alternating phases until 1700 CE. • Valley aggradation ended early in 1850 as a phase of historic arroyo cutting began. • Geomorphological evolution around Basilicata during the LIA was very rapid and controlled by extreme surface process sensitivity to climate change. There is a general consensus that the increased frequency of extreme climatic events will quickly change the morphology of the landscapes in the Mediterranean area. Knowing and understanding the expected changes becomes crucial for defining future adaptive strategies. This paper deals with the very rapid geomorphological evolution in an emblematic Mediterranean area, the Basilicata region of southern Italy, during the last 300 years. The results show that the landscape evolution was mainly controlled by the extreme sensitivity of surface processes to climate change. Landslides, a new cycle of the formation of badland landforms such as calanchi and biancane, and an aggradation/incision phase in the main river valleys have completely reshaped the landscape of the Bradanic Trough, whereas fresh eroded material was moved to the coast. New data on valley-fill alluvium in the Basento River and one of its main left tributaries, the Vella stream, show ages ranging from 1700 to 1850. This deposition phase coincides with the Little Ice Age, an epoch of global climate variability. Previous literature showed that the alluvium of this age consists of a mappable stratigraphic unit outcropping in all the large alluvial valleys of the Basilicata and Mediterranean regions. Palaeoclimate and high-resolution palaeoflood data indicate that valley-fill alluviation occurred during a long humid period. Valley aggradation ended in approximately 1850 with the beginning of a new phase of historic arroyo cutting, mainly due to high magnitude-low frequency rainy events within prolonged drought periods. The stream incision drew the terminal dissection of the clayey slopes into biancana rounded morphologies. These data seem to be confirmed by the comparable heights of about 3 m, both of the biancane and of the fluvial terraces. [ABSTRACT FROM AUTHOR]

• DSOLMap is a new high-resolution global digital soil property map for the SWAT + model. • Soil data play a crucial role in the hydrological cycle and its modelling. • An impact on streamflow performance using different global soil maps was observed. • The use of DSOLMap allows for an improved daily flow simulation. • DSOLMap can be useful for hydrological modelling in regions with limited soil data. This research paper addresses the ongoing challenge of developing fine-resolution global digital soil property maps for hydrological modelling applications. Hydrological models are essential for understanding watershed dynamics and the impact of human activities on water resources. Soil data, which plays a crucial role in the hydrological cycle, is a requisite model input. Global digital soil property maps usually have coarse spatial resolutions, adding considerable uncertainty to hydrological models despite calibration efforts. To address this issue, a new global digital soil property map with 250 m spatial resolution, known as Digital Soil Open Land Map (DSOLMap), was developed and evaluated in this study. The DSOLMap has a finer spatial resolution than existing global soil maps and a more detailed soil profile divided into six soil horizons. This new high-resolution global digital soil property map was tailored to the SWAT + model format. SWAT + is the latest released version of the Soil and Water Assessment Tool (SWAT), one of the most comprehensive hydrological models, and is widely used worldwide. A hydrological evaluation was conducted with the DSOLMap and its results were compared to two other global soil databases using the SWAT + model in a basin located in the north of Spain. The findings showed that using more detailed, finer-resolution soil data, such as those that the DSOLMap offers, improved the hydrological performance of the SWAT + model on a daily scale before and after calibration and validation procedures. The DSOLMap represents a global step forward in hydrological modelling, notably for regions with scarce or unavailable soil information. This new digital soil property map can help decision-makers address global challenges related to water resources and environmental issues through hydrological modelling. [ABSTRACT FROM AUTHOR]