Water Erosion Processes Research Articles

Water erosion processes: Mechanisms, impact, and management strategies

This study rigorously explores water erosion, a critical environmental challenge diminishing land productivity and ecosystem stability worldwide. Addressing a notable gap in comprehensive, region-specific erosion assessments, this research underscores innovative strategies integrating traditional practices with modern technologies. It assesses the interplay between splash erosion, surface runoff, and subsurface flow, which collectively drive significant landscape changes and soil fertility loss. The influence of key factors such as rainfall intensity, soil type, topography, and vegetation is analyzed through case studies from the Loess Plateau, the Mississippi River Basin, and the Ethiopian Highlands, illustrating varying erosion dynamics. Importantly, this work evaluates the implementation of nanotechnology and biotechnological advances in soil stabilization, supported by robust policy frameworks, and demonstrates these technologies in context, ensuring relevancy to the observed erosion processes. By combining empirical research with cutting-edge science and active community participation, this paper champions adaptive and inclusive strategies to effectively manage water erosion, aiming to bolster environmental sustainability and resilience globally.

A thermal infrared imaging observation system for the measurement of overland flow velocities under controlled laboratory conditions

Flow velocity is an important physical parameter in characterizing the hydraulics of water flow. The accurate measurement of overland flow velocities has great significance for understanding and modeling sediment transport and soil erosion. In this study, a Thermal Infrared Imaging Observation System (TIIOS) based on thermal infrared imaging techniques and computer vision recognition technology was established to measure overland flow velocities under controlled laboratory conditions. TIIOS has three subsystems including thermal tracer control, image acquisition and transmission, and image storage and processing. It can be used to dynamically monitor changes in shallow flow velocity by means of automatic control of thermal tracer, instantaneous image acquisition, image correction, noise removal and centroid determination. The observation precision was high with a standard deviation of 0.004 m·s−1 for flow velocity, a temporal resolution of 1/9th s, and a spatial resolution of 2 mm. The new system achieved higher accuracy compared to the traditional dye tracing and salt tracing techniques in observing the dynamic transport process of thermal tracer movement. The relative errors of the centroid velocity measured by the TIIOS ranged from −9.83 % to 6.40 %; whereas the relative errors of centroid velocity measured by salt tracer ranged from −21.36 % to 17.22 %. Measurements by the established TIIOS under different hydraulic conditions demonstrate that the relative errors of the centroid velocity are all smaller than those of the leading-edge velocity. This observational system provided a reliable way to measure shallow flow velocity for better understanding the mechanisms of water erosion processes and showed its potential to be used in field experiments under natural conditions.

Potential Reduction of Spatiotemporal Patterns of Water and Wind Erosion with Conservation Tillage in Northeast China

Conservational tillage (NT) is widely recognized globally for its efficacy in mitigating soil loss due to wind and water erosion. However, a systematic large-scale estimate of NT’s impact on soil loss reduction in Northeast, China’s primary granary, remains absent. This study aimed to investigate the spatial and temporal variability of soil erosion under NT compared to conventional tillage (CT) in the black soil region and to analyze the underlying mechanisms driving these erosions. The Revised Universal Soil Loss Equation (RUSLE) and the Revised Wind Erosion Equation (RWEQ) models were employed, incorporating previously published plot/watershed data to estimate the potential reduction of water and wind erosion by NT in this region. Results indicated that under CT practices, water- and wind-induced soil losses were widely distributed in the arable land of Northeast China, with intensities of 2603 t km−2 a−1 and 34 t km−2 a−1, respectively. Furthermore, the erosive processes of water and wind erosion were significantly reduced by 56.4% and 91.8%, respectively, under NT practices compared to CT. The highest efficiency in soil conservation using NT was observed in the mountainous regions such as the Changbai Mountains and Greater Khingan Mountains, where water erosion was primarily driven by cropland slopes and wind erosion was driven by the wind speed. Conversely, the largest areas of severe erosion were observed in the Songnen Plain, primarily due to the significant proportion of arable land in this region. In the plain regions, water-induced soil loss was primarily influenced by precipitation, with light and higher levels of erosion occurring more frequently on long gentle slopes (0–3°) than on higher slope areas (3–5°). In the temporal dimension, soil loss induced by water and wind erosion ceased during the winter under both tillage systems due to snow cover and water freezing in the soil combined with the extremely cold climate. Substantial reductions were observed under NT from spring to autumn compared to CT. Ultimately, the temporal and spatial variations of soil loss under CT and NT practices were established from 2010 to 2018 and then projected onto a cropland map of Northeast China. Based on this analysis, NT is recommended as most suitable practice in the southern regions of Northeast China for maintaining soil health and crop yield production, while its suitability decreases in the northern and eastern regions.

Surface Flux Patterns of Nutrient Concentrations and Total Suspended Solids in Western Carpathian Stream within Agricultural, Forest, and Grassland Landscapes

The intricate processes of surface water erosion are vital for ecological systems and river-scale management; yet, understanding them comprehensively remains a challenge. Forested agricultural catchments, especially in the Carpathian region, face significant degradation, potentially leading to inorganic nutrient leaching and total suspended solid (TSS) flux. Continuous rainwater inundation of soils in river valleys exacerbates this issue. Utilizing innovative tools like SWAT+, studies have revealed higher concentrations of inorganic nutrients in main watercourses from flysch catchments, with agricultural use linked to N-NO3− concentrations and pasture use linked to anion P-PO43−. Maintaining detailed records is crucial for researchers comparing data. SWAT+ proves valuable for studying TSS washing out and inorganic nutrient leaching, informing collaborative watershed management policies involving stakeholders from agriculture, conservation, and water management sectors. The insights on nutrient leaching, particularly phosphorus (P) and nitrogen (N), are instrumental for shaping policies targeting nutrient pollution within pasture land use for EU agriculture. These findings can guide policy frameworks focused on sustainable practices, especially for eco-schemes, and encourage collaborative watershed management efforts.

Dynamic Replacement of Soil Inorganic Carbon under Water Erosion

The dynamic replacement of soil organic carbon represents a pivotal mechanism through which water erosion modulates soil–atmosphere CO2 fluxes. However, the extent of this dynamic replacement of soil inorganic carbon within this process remains unclear. In our study, we focused on Yuanmou County, China, a prototypical region afflicted by water erosion, as our study area. We leveraged the WaTEM/SEDEM model to quantify the dynamic replacement of soil carbon, accounted for the average annual net change in soil carbon pools, and used isotope tracer techniques to track and measure the process of the coupled carbon–water cycling. This comprehensive approach enabled us to scrutinize the dynamic replacement of soil carbon under water erosion and delineate its ramifications for the carbon cycle. Our findings unveiled that the surface soil carbon reservoir in the Yuanmou area receives an annual replacement of 47,600 ± 12,600 tons following water erosion events. A substantial portion, amounting to 39,700 ± 10,500 tons, stems from the dynamic replacement of soil inorganic carbon facilitated by atmospheric carbon. These results underscore the critical role of the dynamic replacement of soil inorganic carbon in altering the soil–atmosphere CO2 fluxes under water erosion, thereby influencing the carbon cycle dynamics. Consequently, we advocate for the integration of water erosion processes into regional carbon sink assessments to attain a more comprehensive understanding of regional carbon dynamics.

Soil hydro-physical variables and crop residues determinate runoff, soil loss, and glyphosate and AMPA concentration in the aqueous phase under simulated rainfall events.

Soil structural degradation and water erosion processes were observed even in no-tillage schemes in the Pampas region. Within these conservation systems, agrochemical application per hectare is one of the highest globally. Thus, this entails a serious risk of water contamination. The objectives of this study were to (1) test the hypothesis that the hydrological dynamics and sediment concentration related to surface runoff were conditioned by soil structure regardless of the presence of maize (Zea mays L.) crop residue and (2) assess the incidence of maize crop residue on glyphosate and aminomethylphosphonic acid (AMPA) concentration in runoff. The soil under study corresponded to Arroyo Dulce Series (Typic Argiudoll silty loam soil). Rain simulations were performed in the laboratory on undisturbed soil samples. Total runoff and infiltration rate were similar between treatments with C(+) and without C(-) maize crop residues (C(+) 1381.40mL and 14.27mm h-1, C(-): 1529.70mL and 21.67mm h-1). The C(-) treatments showed a higher sediment concentration than C(+) (1.58 and 0.42g 100mL-1, respectively). Glyphosate and AMPA average values in runoff were 15.9 and 33.9µg L-1. High variability of the hydro-physical properties and occurrence of soil structure, particularly platy ones, were detected. The hydrological variables were conditioned mainly by the occurrence of platy structures regardless of crop residue presence. Glyphosate concentration was increased in the first runoff event by the presence of corn residues, while AMPA concentrations were higher in the second runoff event in both residue treatments. In this study, maize residue on the soil surface protected the soil from sediment detachment but did not change runoff or infiltration. Thus, the implementation of agricultural management practices that promote vegetative residue cover has shown positive results to erosion.

Modelling, quantification and estimation of the soil water erosion using the Revised Universal Soil Loss Equation with Sediment Delivery Ratio and the analytic hierarchy process models

AbstractThis research used the Revised Universal Soil Loss Equation (RUSLE) with Sediment Delivery Ratio (SDR) model. The analytic hierarchy process (AHP) method, while also incorporating the use of a geographic information system (GIS) and remote sensing (RS) to predict the annual soil loss rate and spatialise the processes of water erosion at the scale of the Loukkos Watershed, Morocco. The RUSLE model and AHP parameters were estimated using RS data, and the erosion vulnerability zones were determined using GIS. We used five parameters, including precipitation erosivity, soil erodibility, slope length and steepness, vegetation cover, and soil erosion control practices in the RUSLE. For the AHP technique, we used seven geo‐environmental factors, including annual average precipitation, drainage density, lineament density, slope, soil texture, land use/land cover and landform maps. The results of RUSLE indicated that the average annual soil loss varied from 0 to 2388.27 . The total estimated annual potential soil loss was approximately 40 790 220.11 , and a sediment yield estimated by RUSLE‐SDR was 8 647 526.66 , equivalent to 6.65 Mm3. This value is very close to the measured value of 6.81 Mm3, for a difference of 0.16 Mm3. Furthermore, the results of the AHP indicate that the soil erosion potential index varies from 0 to 0.205315 . Overall, nearly 13.7% of the area suffered from severe soil erosion exceeding 50 . Approximately 80% of the Loukkos Watershed area experienced only slight erosion, while the remaining 6% incurred moderate erosion. Integrating GIS and RS into the RUSLE model and AHP helped us robustly estimate the extent and degree of erosion risk. Territorial decision‐makers should adopt our results to develop soil conservation strategies, water management plans and other necessary soil and water conservation measures for this region.

Water Erosion Response to Rainfall Type on Typical Land Use Slopes in the Red Soil Region of Southern China

Land use and rainfall are two important factors affecting soil erosion processes. The red soil region of southern China is a representative region with high rainfall amounts and rapidly changing land use patterns where the water erosion process is sensitive to changes in land use and rainfall. To comprehensively understand the water erosion response to land use and rainfall in this region, a 6-year in situ experiment based on eight plots (bare land and seven typical land uses) was conducted from 2015 to 2020. The 320 rainfall events were divided into 4 types, and there were 3 main rainfall types. The runoff of different rainfall types was primarily determined by the rainfall amount, while the soil erosion of different rainfall types was primarily determined by the rainfall intensity. High-intensity rainfall contributed the most to both total runoff and soil erosion. Compared with bare land, the seven typical land uses reduced runoff and soil erosion by more than 75%. Grassland, cropland, and forest with low vegetation coverage experienced high runoff and soil erosion, while shrubland most effectively reduced runoff and soil erosion. The combination of land use and rainfall type significantly affected the annual average runoff depth, soil erosion modulus, and soil loss coefficient. Rainfall types can change the relationship between runoff and soil erosion for different land uses. The runoff and soil erosion of bare land were highly correlated with rainfall characteristics, while vegetation weakened this relationship under short- or moderate-duration rainfall. To effectively reduce water erosion, high-intensity rainfall should receive special attention, and all land uses should ensure that vegetation is well developed, especially understory vegetation.

ТРАНСФОРМАЦИЯ ЗЕМЕЛЬ СЕЛЬСКОХОЗЯЙСТВЕННОГО НАЗНАЧЕНИЯ В РАЙОНАХ ИНТЕНСИВНОГО ЗЕМЛЕДЕЛИЯ

The article presents the results of a study of agricultural landscapes in the Amorda River basin, one of the highly developed river basins of the Republic of Mordovia. The assessment of the factors of the development of water erosion was carried out, the main patterns of spatial and temporal propagation of water erosion processes were revealed. Recommendations for optimizing agricultural land use are proposed.

Water Erosion Processes on the Geotouristic Trails of Serra da Bocaina National Park Coast, Rio de Janeiro State, Brazil

Conservation units are strategic territories that have a high demand for public use, as they protect attractions of great scenic beauty, geodiversity sites, and numerous leisure areas. However, when carried out in an intensive and disorderly manner, tourist activity in these areas tends to catalyze environmental degradation, triggering, for example, water erosion processes caused by intensive soil trampling on the trails. In this sense, the aim of this study was to determine the soil’s physicochemical characteristics, and to spatiotemporally monitor the microtopography of those areas degraded by erosion along two trails on Serra da Bocaina National Park coast of the Paraty Municipality. The findings verified that intensive trampling, the values of some soil physicochemical characteristics, and the specific meteorological conditions of the coastal region of this protected area were factors that contributed significantly to the evolution of erosion features monitored on these trails. Finally, strategies for appropriate management and recovery actions for these degraded areas are proposed in order to not only stop the erosive processes and re-establish the local ecosystem balance, but also avoid accidents involving the numerous tourists who visit the coastal region.

Integrated Use of the Ravine-Gully Systems as a Tool of Water Erosion Processes Counteracting

The article studies the topical problems in counteracting the processes of agricultural land degradation
 in the Rostov region. It emphasizes the importance of the integrated ameliorative arrangement of the
 ravine-gully systems aimed at mitigating the consequences of the water erosion, and describes the
 practical experience of implementing such measures. It is substantiated that it is the integrated approach that enables protection of the soils, most susceptible to erosion processes, increases soil-fertility and, on the whole, ensures more sustainable use of land resources

The Throughfall, Stemflow, and Canopy Interception Loss in Corn and Soybean Fields in Northeast China

Information about throughfall, stemflow, and canopy interception loss is essential for the water use efficiency of crops and the dynamic processes of water erosion. A two-year field experiment was conducted under natural rainfall conditions to observe the characteristics and factors that affect throughfall, stemflow, and canopy interception loss in corn (Zea mays L.) and soybean (Glycine max L.) fields in northeast China from 2019 to 2020. Nine measurement sites (A, B, C, D, E, F, G, H, and I) were distributed horizontally between two planting rows under the crop canopy. The mean value of the throughfall volume (TF) in measurement locations B, C, and G under the corn canopy and measurement locations B and C could represent the mean level of TF of corn and soybean fields, respectively. The volume of TF, stemflow (SF), and canopy interception loss (CI) of two growing seasons from 2019 to 2020 accounted for approximately 58.5%, 30.1%, and 11.4% of the gross rainfall (GR) of two growing seasons in corn fields, and 78.0%, 7.5%, and 14.5% of the GR in the soybean field, respectively. The TF and TFR of each rainfall event in the corn and soybean fields could be predicted by linear regression models with a normalized root mean square error (NRMSE) lower than 25.0%. These results and prediction models will be used in water management and soil erosion control in northeast China.

Soil peroxidase and polyphenoloxidase activity under soil conservation practices on sloping terrains

Soil water erosion in Bulgaria has a significant negative impact on the arable inclined lands. Two experiments were conducted with wheat and maize with application of traditional and soil protection technologies, on Calcic Chernozem soil, on the slope of 5°. Calcic Chernozems are soils exposed to frequent water erosion processes due to significant structural deficiency and low aggregate stability. The first survey was carried out in the period 2018-2020, and in addition to conventional technologies, surface and vertical mulching (with manure as mulching material) were also tested. The second was carried out in 2020-2023 and included minimal treatments for growing wheat and maize and the inclusion of cover crop (barley) in the crop rotation. An increase in the amount of soil organic carbon was found, as well as an increase of the soil peroxidase and polyphenoloxidase activity. The ratio between two enzymes, is considered as humification factor, is higher in the variants under soil protection technologies. The application of soil conservation treatments such as surface mulching with manure, minimum tillage with vertical manure mulching, as well as minimum tillage combined with cover crop in a wheat-maize rotation on sloping farmlands lead to an improvement of soil organic carbon as well as an increase of soil polyphenoloxidase activity.

The effect of slope incline on the characteristics of particles ejected during the soil splash phenomenon

Slope incline is one of the factors affecting the soil water erosion process. Most of the work to date related to erosion has been on large-scale studies based on rainfall events or laboratory investigations with the use of simulators, where the displaced mass of soil was determined. However, there is a lack of studies providing information about splash erosion on slopes in relation to single-drop impact methodology, that allows for the examination of the basic processes of the phenomenon. Thus, the aim of this study was a quantitative description of the splash phenomenon on a simulated slope affected by a single drop impact, with respect to the influence of slope incline on the number of ejected particles and their characteristics. The investigation was carried out using three types of soil with different textures in moistened conditions (i.e. pressure head corresponding to 1.0 kPa) and three variants of slope incline: 5°, 15°, and 30°. A drop with a diameter of 4.2 mm was allowed to fall freely on soil surface with kinetic energy equal 1.42 mJ. The splash phenomenon was registered by a set of three synchronized high-speed cameras and combined with PTV software (Particle Tracking Velocimetry) to identify and track displaced particles. The methodology used made it possible to observe the course of the phenomenon and determine the following quantities: the number and size of ejected particles, ejection velocity and angle, displacement range, and also the contribution of the kinetic energy of the falling drop transferred to the ejected particles. The measured quantities were specified for the particles ejected in upslope and downslope directions. It was found that: (i) the interaction between different slope inclines and the particle size distribution of the soils influenced the surface conditions, which had a significant effect on the course of the splash phenomenon; (ii) the number of ejected particles decreased with the increasing slope, which was directly related to limited ejection in the upslope direction; (iii) the influence of slope incline was mostly visible in the ejection angle, range of displacement and sizes of ejected particles; (iv) the portion of the falling drop energy transferred to ejected particles decreased with increasing slope. The obtained results could enhance the development of physical models of splash erosion. A more thorough understanding and better recognition of the mechanisms governing this phenomenon at all stages could contribute to the development of more effective methods for protecting soil against erosion.

Influence law of modified glutinous rice-based materials on gravel soil reinforcement and water erosion process

Influence law of modified glutinous rice-based materials on gravel soil reinforcement and water erosion process

Effects of rock outcrops on runoff and erosion from karst slopes under simulated rainfall

AbstractRock outcrops play a crucial role in affecting hydrological and erosion processes on karst hillslopes. However, due to various difficulties in constructing runoff plots on field rocky slopes, previous studies used small metal flumes to simulate outcropped slopes, which greatly differed from the natural rock outcropped slopes. In this study, the effects of rock outcrops on runoff and erosion were studied on karst slopes with natural soil–rock conditions at a larger plot scale (10 m in length × 2.2 m in width, 25° in gradient). Simulated rainfall experiments were conducted on the four runoff plots with different rock outcrop coverages (0%, 5%, 13%, and 42%) under five rainfall intensities (30, 60, 90, 120, and 150 mm·h−1). The study indicated that the rock outcrops complexed the water erosion processes by playing multiple and opposite roles simultaneously. It positively influences water erosion by serving as impermeable surfaces, providing preferential flow paths, and offering flow barriers to hillslopes. Conversely, it can exacerbate erosion by causing increased runoff, concentrating flow paths, and thus intensifying erosion in specific areas. Besides, the effects of these roles varied with the coverage of rock outcrops and rainfall intensity. The main results showed that (i) limited rock outcrop coverage (5% and 13%) increased runoff and erosion, but the opposite was observed on the severe rocky slope (42%). Both “infiltration‐excess” and “saturation‐excess” mechanisms coexisted by turns on karst slopes during rainfall; the break of “saturation balance” tended to occur on the severe rock outcrop slope with abundant soil–rock interface and underground fissures. (ii) Rock outcrops greatly increased the spatial variability and uncertainty of hydrological and erosion processes on karst slopes. The rock outcrops resulted in a larger range of variation in flow velocity and a greater difference among the three slope positions; it also brought more spatial heterogeneity in the development of rill erosion. (iii) Rock outcrops tended to increase flow velocity, and intensify flow turbulence, stream power, and flow energy. The severe rock outcrops significantly reduced the soil erosion induced by the limited soil detachment. This study contributes to a deeper understanding of the mechanisms behind how rock outcrops influence runoff and erosion and provides insights for improving soil erosion prediction in karst regions.

CHANGES IN HYDROGEOLOGICAL CONDITIONS DURING BOGGING IN THE SOUTHEAST OF THE WEST SIBERIAN PLAIN

Link for citation: Savichev O.G. Changes in hydrogeological conditions during bogging in the southeast of the West Siberian plain. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 10, рр. 187-198. In Rus. Relevance of the research is determined by the need to understand the mechanisms of interaction between groundwater, swamp and river waters in conditions of severe swampiness in the taiga zone of Western Siberia to solve a number of scientific and engineering problems both at present and in the future. The aim: quantitative assessment of changes in the levels of groundwaters during the characteristic periods of swamping of the southeast of the West Siberian Plain: 1) the beginning of an intensive spread of peat swamps with a peat deposit thickness of 0,3 m or more; 2) oligotrophization of swamps. Methods: methods of mathematical modeling, statistical methods. Results and conclusions. The author has carried out the analysis of peat deposit structure in the southern part of the Chaya river (a tributary of the Ob river) catchment area. The large-scale formation of peat swamps (with a peat thickness of 0,3 m or more) in the area under consideration occurred approximately 4 thousand years ago; the oligotrophization of the peat deposit (on a regional scale) occurred approximately 2,0…1,5 thousand years ago. In both cases, the main part of the swamps presumably could be attributed to the lowland type, but compared with the modern period in the first case their total area was 2 times less, and in the second was 1,7 times more. Taking into account these estimates, the average values of infiltration Inf and filtration coefficients Kf were determined, the ratio Inf/Kf dependence on the area of low-moor peat swamps was obtained, and groundwater levels were calculated at the present time and for periods of 1,7 and 4,1 thousand years ago. During the oligotrophization of the peat deposit (approximately 2,0...1,5 thousand years ago), with a high probability, there was a deterioration in water exchange between swamps and underground aquifers and an increase in groundwater levels. The beginning of intensive regional swamping (about 4 thousand years ago) occurred against the background of intense water-erosion processes. This results in accumulation of river alluvium accompanied by a rise in the levels of river water and then groundwater.

Remote Sensing applications for effective fire disaster management plans: A review

The current context of climate change and imminent global warming is leading to changes in temperature and rainfall patterns worldwide which affect soil moisture, vegetation and soil conditions, the incidence of dry and wet events, and consequently, the occurrence, intensity, and magnitude of fires. Fires harm people’s quality of life as they can disrupt economic activities and affect public health. Additionally, fires damage the environment, accelerating water and wind erosion processes, altering air quality, and contributing to ecosystem degradation. Pampas in Argentina was selected as an example to study fires at a regional scale using Remote Sensing techniques due to its status as one of the most fertile plains in the world and the country’s most densely populated area. The fires are carefully analyzed and described considering three stages: i) pre-fires, ii) fires, and iii) post-fires. Afterwards, fire disaster management plans are described to assess these events, reduce their impacts on society and biodiversity, and minimize the ecosystems’ recovery time. In this sense, this manuscript aims to review the relationships between climate change, global warming, and the occurrence of fires. Additionally, it proposes to analyze the potential of Remote Sensing in analyzing these events at a regional scale to provide the mechanisms and tools necessary for formulating fire disaster management plans.

Remote Sensing applications for effective fire disaster management plans: A review

The current context of climate change and imminent global warming is leading to changes in temperature and rainfall patterns worldwide which affect soil moisture, vegetation and soil conditions, the incidence of dry and wet events, and consequently, the occurrence, intensity, and magnitude of fires. Fires harm people’s quality of life as they can disrupt economic activities and affect public health. Additionally, fires damage the environment, accelerating water and wind erosion processes, altering air quality, and contributing to ecosystem degradation. Pampas in Argentina was selected as an example to study fires at a regional scale using Remote Sensing techniques due to its status as one of the most fertile plains in the world and the country’s most densely populated area. The fires are carefully analyzed and described considering three stages: i) pre-fires, ii) fires, and iii) post-fires. Afterwards, fire disaster management plans are described to assess these events, reduce their impacts on society and biodiversity, and minimize the ecosystems’ recovery time. In this sense, this manuscript aims to review the relationships between climate change, global warming, and the occurrence of fires. Additionally, it proposes to analyze the potential of Remote Sensing in analyzing these events at a regional scale to provide the mechanisms and tools necessary for formulating fire disaster management plans.

Quantification of red soil macropores affected by slope erosion and sediment using computed tomography

AbstractSoil structure is an important factor interacting with soil erosion and sediment processes. However, few studies have focused on the relationship between soil macroporosity and soil erosion across different terrains. The aim of this study was to quantify and compare soil properties and macroporosity characteristics in collapsing gully areas and to explore their impact on the formation and development of collapsing gullies. Soil cores were excavated at different positions of a typical collapsing gully and then scanned to analyze soil macropores. Soil properties and saturated hydraulic conductivity were also investigated. The results showed that the contents of sand, silt, and clay, the mean weight diameter of aggregates, and the infiltrate rates varied at different positions. The valley had the greatest macroporosity (1.09% ± 0.33%), the number (5919 ± 703), volume (1468 ± 194 mm3), and surface area (10.4 ± 2.6 m2) of macropores, as well as the mean volume (16.8 ± 7.4 mm3) of macropores >1 mm3, whereas these indices were lowest at the slope (0.15% ± 0.14%, 1189 ± 747, 266 ± 188 mm3, 1.7 ± 1.4 m2, and 10.6 ± 2.9 mm3, respectively). The macroporosity and the number of macropore decreased with increasing depth but were also influenced by the erosion and sediment processes. The processes of sediment and the roots of vegetation also influenced the orientation of the macropores. Macropore characteristics at different sites of the collapsing gullies affected the soil water infiltration and hydraulic conductivity and further affected the processes of water erosion and mass erosion.