Erosion Dynamics Research Articles

Evaluation of loess-filled slope failure triggered by groundwater rise using a flume test

Gully Stabilization and Highland Protection (GSHP) are useful in preventing gully erosion and have been widely utilized in the Loess Plateau of China. Groundwater rise is an important factor that can lead to loess-filled slope instability. A flume device was designed to study the process of water infiltration into a loess-filled slope and the subsequent failure process of the slope due to groundwater rise. The loess was uniformly infiltrated with water, resulting in preferential seepage via the development of cracks in the slope from settlement deformation. The pore-water pressure increased in the front of the slope and decreased at the back during slope failure, due to contraction in the slope toe and increased tensional at the back of the slope. The failure process of the slope can be divided into three stages, settlement deformation and collapse deformation with vertical displacement during slope settlement, and slope toe slide-flow or regressive failure with a primarily horizontal displacement in the direction of the slope’s free surface. The factors of suffusion erosion, saturated softening, and infiltration dynamics during water infiltration into the loess-filled slope promote slope failure according to experimental data and numerical simulations.

Quantifying Understory Vegetation Cover of Pinus massoniana Forest in Hilly Region of South China by Combined Near-Ground Active and Passive Remote Sensing

Understory vegetation cover is an important indicator of forest health, and it can also be used as a proxy in the exploration of soil erosion dynamics. Therefore, quantifying the understory vegetation cover in hilly areas in southern China is crucial for facilitating the development of strategies to address local soil erosion. Nevertheless, a multi-source data synergy has not been fully revealed in the remote sensing data quantifying understory vegetation in this region; this issue can be attributed to an insufficient match between the point cloud 3D data obtained from active and passive remote sensing systems and the UAV orthophotos, culminating in an abundance of understory vegetation information not being represented in two dimensions. In this study, we proposed a method that combines the UAV orthophoto and airborne LiDAR data to detect the understory vegetation. Firstly, to enhance the characterization of understory vegetation, the point CNN model was used to decompose the three-dimensional structure of the pinus massoniana forest. Secondly, the point cloud was projected onto the UAV image using the point cloud back-projection algorithm. Finally, understory vegetation cover was estimated using a synthetic dataset. Canopy closure was divided into two categories: low and high canopy cover. Slopes were divided into three categories: gentle slopes, inclined slopes, and steep slopes. To clearly elucidate the influence of canopy closure and slope on the remote sensing estimation of understory vegetation coverage, the accuracy for each category was compared. The results show that the overall accuracy of the point CNN model to separate the three-dimensional structure of the pinus massoniana forest was 74%, which met the accuracy requirement of enhancing the understory vegetation. This method was able to obtain the understory vegetation cover more accurately at a low canopy closure level (Rlow2 = 0.778, RMSElow = 0.068) than at a high canopy closure level (RHigh2 = 0.682, RMSEHigh = 0.172). The method could also obtain high accuracy in version results with R2 values of 0.875, 0.807, and 0.704, as well as RMSE of 0.065, 0.106, and 0.149 for gentle slopes, inclined slopes, and steep slopes, respectively. The methods proposed in this study could provide technical support for UAV remote sensing surveys of understory vegetation in the southern hilly areas of China.

Combining sediment source tracing techniques with traditional monitoring: The “Arvorezinha catchment” experience

AbstractTo truly understand the hydrologic and erosive processes that occur at the catchment scale regarding land use and soil management changes, intensive monitoring is required over a long period. Variables such as precipitation, flow rate and suspended sediment concentration are the fundamentals needed to estimate sediment yield (SY). However, in order to shed more light on the effects of soil management changes on SY, traditional hydrologic monitoring techniques can be paired with sediment tracing to identify sediment sources. In addition, mathematical models that predict erosion and SY can also help understand the dynamics of erosion and deposition between the hillslope and stream channel. Given the above, this article provides an overview of almost 20 years of monitoring (2002–2021) in the Arvorezinha experimental catchment (1.23 km2) located on the edge of the Brazilian meridional plateau in southern Brazil, which is subject to extreme erosion due to a combination of factors related to intensive agriculture and steep slopes. The catchment was selected as a study site to evaluate the effects of land‐use changes and soil conservation management on hydrology and SY. The text reviews the history of the study, synthesizes the main results and describes the evolution of the monitoring techniques used while giving special attention to the fingerprinting approach. In addition, the article discusses the importance of catchment‐scale studies for teaching, generating technical‐scientific knowledge and fostering collaboration between national and international research groups.

Stability of travertine barrier on Milino Lake

In March 2018, part of the travertine barrier at Milino Lake, in Plitvice Lakes National Park in Croatia, broke off, significantly altering the flow of water over the barrier. Encouraged by this event, the Faculty of Civil Engineering in Rijeka conducted a monitoring and analysis of the erosion dynamics of the travertine barriers on Plitvice Lakes. Within the project, the analyses of the stability of the travertine barriers were carried out. To the author's knowledge, physical and mechanical properties of travertine have been determined for the first time on samples excluded from travertine barriers between cascading lakes. In addition, no one has previously checked the stability of the travertine barrier located between the two lakes. The maximum compressive and tensile stresses calculated on a numerical model of the broken part of the barrier are compared with the compressive and tensile strength determined by laboratory tests on travertine samples taken from the broken barrier. By comparing the calculated stresses and determined travertine strength, it was found that the stability of the analysed part of the broken travertine barrier at Milino Lake was compromised even if only the self-weight of the collapsed part of the barrier is taken into account.

Assessing land erosion and accretion dynamics and river bank line shifting of upper reach of Hooghly river of West Bengal, India

Assessing land erosion and accretion dynamics and river bank line shifting of upper reach of Hooghly river of West Bengal, India

A cloud-based mapping approach for assessing spatiotemporal changes in erosion dynamics due to biotic and abiotic disturbances in a Mediterranean Peri-Urban forest

During the last decades, the demographic trajectory and the associated urban development have increased the demand for urban and peri-urban green space. Peri-urban forests provide a wide range of goods and services to city dwellers critical to human well-being. However, these ecosystems are particularly vulnerable to biotic and abiotic stresses. This study aimed to assess the effects of forest disturbances on soil erosion dynamics in a peri-urban forest of Northern Greece, between 1995 and 2020. Monitoring of soil erosion dynamic was performed by coupling the Google Earth Engine (GEE) cloud-computing platform and the RUSLE erosion prediction model. The results highlighted the potential of Landsat imagery to efficiently delineate through time forest cover changes due to the influence of biotic and abiotic factors. After a major fire event, average soil erosion showed an increase of 7.7 t/ha/year whilst the emergency hillslope rehabilitation treatments led to a decrease equal to 8.9 t/ha/year. On the contrary, post-fire watershed stabilization measures and selective logging for the removal of the infested individual trees had a negligible effect on soil loss. The temporal changes in soil loss rate are not only justified by forest cover changes but also by the variability in rainfall, which is also considered a dynamic factor of RUSLE model. Monitoring of soil loss and erosion regulation services over peri-urban forests provide essential information for policy-making and management of these valuable natural resources.

Study on Dynamic Changes of Soil Erosion in the North and South Mountains of Lanzhou

The North and South Mountains of Lanzhou City are the ecological protection barriers and an important part of the ecological system of Lanzhou City. This study takes the North and South Mountains as the study area, calculates the soil erosion modulus of the North and South Mountains of Lanzhou City based on the five major soil erosion factors in the RUSLE model, and analyses the spatial and temporal dynamics of soil erosion in the North and South Mountains of Lanzhou City and the soil erosion characteristics under different environmental factors. The results of the study show that: The intensity of soil erosion is dominated by slight erosion, which was distributed in the northwestern and southeastern parts of the North and South Mountains in 1995, 2000, 2005, 2010, 2015 and 2018. Under different environmental factors, the soil erosion modulus increased with elevation and then decreased; the soil erosion modulus increased with a slope; the average soil erosion modulus of grassland was the largest, followed by forest land, cultivated land, unused land, construction land, and it was the smallest for water; except for bare land, the average soil erosion modulus decreases with the increase of vegetation cover; Soil erosion modulus was the greatest in the pedocal of the North and South Mountains, and the least in the alpine soil.

Historical and projected changes in hydrological and sediment connectivity under climate change in a tropical catchment of Mexico

Hydrological and erosion dynamics are prone to change due to natural factors, human activities, or climate change. These changes are mainly related to modifications of land use and cover and can be assessed through the concept of connectivity, which analyzes how the spatial distribution of the elements facilitates runoff and sediment transport. The objective of this study was to evaluate changes in hydrological and sediment connectivity over 42 years and projected under a climate change scenario in the tropical Santa Cruz catchment in Aquismón, S.L.P., Mexico. The index of connectivity (IC) was computed using SedInConnect version 2.3 and the ArcSWAT model to estimate runoff. Hydrological connectivity and runoff were projected for 2027 using the MPI ECHAM 5 in the A2 climate change scenario. The results indicated that spatio-temporal changes in land use/cover, in conjunction with geomorphological features and expected climate change, would modify hydrological and sediment connectivity, especially in flat areas, where conversion of natural vegetation to cropland was steadily increasing over the years. Under future conditions, runoff and sediment transport are likely to increase, which will impact soil erosion and vulnerability to flooding but will not necessarily be negative. The study shows how spatial-temporal integration of runoff, sediments, landforms, land use cover and change, and connectivity can improve our understanding of catchment dynamics and the importance of analyses that characterize their evolution. The results can subsequently be applied and replicated in other catchments for management and restoration purposes.

Erosion and siltation dynamics in an urban-influenced coastal setting, Xiamen Island, China

The evolution of seafloor erosion-siltation in urban bays has received wide attention owing to its high susceptibility to natural factors and human activity, Xiamen is a typical coastal city in China that has undergone rapid urban development. Here, we studied seafloor erosion-siltation in the sea to the east of Xiamen Island. In particular, we focused on the responses of erosion-siltation to changes in the natural environmental factors and intensive human activity. The spatial distribution and transport trends of surficial sediments, changes in sedimentary records, and erosion-siltation dynamics were analyzed based on surficial sediments, core sediment within a time span of ca.100 years, and new and historical bathymetric data. The results showed that surficial sediments were mainly transported to the northwest and southwest, three stage changes in sedimentary records have occurred, the shoreline gradually moved seaward and became straighter, and the erosion-siltation state shifted from slight erosion to siltation. Before the 1930s, climate change with alternating aridity and humidity controlled the influence area of the Jiulong River sediment input. During the subsequent period (1930s to the early 1970s) of enhanced human activity in the drainage basin, the increased river sediment input only promoted siltation in some of the study areas; however, after the 1970s, river sediment input was no longer a dominant factor in the evolution of erosion-siltation. During the rapid urban development in Xiamen, coastal development and construction on Xiamen Island resulted in a large influx of sediment into the sea directly. This compensated for the decreased river sediment input and shifted the study area toward siltation. Meanwhile, rapid siltation was triggered in some of sediment convergence areas and the Jinmen Channel, where the dredging and maintenance demands were low. While channel dredging and maintenance coupled with sediment back siltation caused significant short-term topography changes in the Xiamen East Channel. Land reclamation directly shrank tidal flats along Xiamen Island. Moreover, normal wind-generated waves and occasional intensification typhoon events affected the long-term evolution of these tidal flats via persistent erosion coupled with coastal transport, and drastic short-term erosion, respectively.

Dynamic Evolution and Quantitative Attribution of Soil Erosion Based on Slope Units: A Case Study of a Karst Plateau-Gorge Area in SW China

Exploring the dynamics of soil erosion and identifying its driving mechanisms is key to understanding soil erosion processes, particularly in karst areas. In this study, the RUSLE model, optimized on the basis of rocky desertification factors, was used to estimate soil erosion in a karst plateau gorge area in SW China. The spatial and temporal dynamics of soil erosion in the region over the past 20 years were analyzed on the basis of slope units, while the relationship between soil erosion and elevation, slope, fractional vegetation cover (FVC), karst rocky desertification (KRD), rainfall, and land use cover/change (LUCC) was identified quantitatively by the geographical detector on the basis of spatial heterogeneity. The results showed that: (1) The no erosion area decreased from 2000 to 2020, with the highest proportion of light to medium erosion and an increasing trend of soil erosion. (2) Soil erosion conversion mainly occurred between no erosion, slight erosion, and light erosion. (3) The hotspots of erosion occurred in high slope–low elevation and high slope–high elevation units, while the coldspots of erosion occurred in low slope–low elevation units. (4) Soil erosion was positively correlated with FVC and slope, and negatively correlated with KRD. (5) The dominant factor of soil erosion changed from KRD-slope to LUCC-slope and finally to elevation-slope, while the q value of rainfall-elevation had the most significant increase throughout the study period. This study will help to advance the goal of sustainable development of soil and water conservation in karst areas.

Transition of a small Himalayan glacier lake outburst flood to a giant transborder flood and debris flow

Glacial lake outburst floods (GLOFs) are a great concern for the Himalaya, as they can severely damage downstream populations and infrastructures. These floods originate at high altitudes and can flow down with enormous energy and change the terrain’s existing morphology. One such devastating event occurred on the night of 5 July 2016, from the inconspicuous Gongbatongsha Lake, located in the Poiqu basin, Eastern Himalaya. The Poiqu basin in the Tibetan Autonomous Region currently contains numerous big glacial lakes; however, this event originated from a small lake. The GLOF was triggered following heavy precipitation that led to a slope failure above the lake and deposition of debris into the lake, which breached the moraine dam and rapidly drained the entire lake. The flood damaged several downstream infrastructures, including the Arniko highway, the Upper Bhotekoshi hydropower plant, and several buildings as it made its way into the Bhotekoshi basin in Nepal. This study adopts a multi-model approach to reconstruct the GLOF trigger and the flood’s transformation into a severe debris flow. Proxies including flow discharge, flow velocity, runout distances were used to calibrate the model and validate the results. Results reveal that a debris flow of volume ranging between 3000 and 6000 m3 from the headwall must have led to lake overfill, eventually leading to the GLOF event. The GLOF showed a significant increase in peak discharge from 618 to 4123 m3 s−1 at the Zhangzangbo-Bhotekoshi confluence. The average velocity of the flow is calculated to be ~ 5.5 m s−1. Reconstruction of the erosion and deposition dynamics show that maximum erosion occurred in the first 6.5 km, with maximum deposition occurring near the Upper Bhotekoshi hydropower station. The modeling indicates that the availability of the entrainable debris along the channel, likely from the previous landslides, amplified the event by three orders of magnitude-additional water ingested from the river. Overall, we demonstrate how the small-scale Gongbatongsha GLOF amplified downstream by incorporating pre-existing sediment in the valley and triggered damaging secondary landslides leading to an economic loss of > 70 million USD.

Evaluating the interaction between snowmelt runoff and road in the occurrence of hillslope instabilities affecting a landslide-prone mountain basin: A multi-modeling approach

The presence of roads in steep slope mountain areas is often linked with the occurrence of landslides and erosive dynamics. The use of Airborne Laser Scanning (ALS)-derived high-resolution topographic data increased the possibilities to better represent landscapes and related physical processes at the watershed scale. Additionally, the adoption of topographically-based hydrological models allows to simulating water overland flows and investigate the occurrence of specific degradative phenomena. Snowpack melting plays a primary role in altering superficial water dynamics in mountain landscapes, but accurate investigation of the interaction between snowmelt runoff and human infrastructures (such as roads and trails) in the occurrence of hillslope failures is still obscure. This research aims to assess the relationship between snowmelt runoff, road presence and terrain instabilities affecting a landslide-prone steep slope mountain meadow (northern Italy). An innovative multi-modeling approach was proposed to detect the alteration of snowmelt overflows due to the presence of the road and its relation with the activation of a shallow landslide. The road role in altering snowmelt runoff was investigated both considering its presence and assuming its absence. Different hydrological and slope stability models were interactively considered, starting from pre-event ALS-derived DEM to compute predictive basin-scale simulations. Results attested the key role played by the road in altering snowmelt runoff pathways, as well as their combined contribution to the foreseen activation of the observed shallow landslide. Starting from on-field observations conducted after the landslide triggering, the accuracy of instabilities predictions was finally tested through the statistical computation of the Area Under the Receiver Operating Characteristic curve (AUC-ROC) and the Cohen’s kappa-index, respectively resulted around 0.9 and 0.6. This work could be a useful tool for planning mitigation interventions able to reduce the occurrence of similar risk scenarios, also providing suggestions for developing and promoting efficient sustainable actions for mountain landscapes.

Assessment of erosion dynamics on Marsa Matrouh coast, Western Egypt, using GIS and RS techniques

Assessment of erosion dynamics on Marsa Matrouh coast, Western Egypt, using GIS and RS techniques

Assessment of Moraine Cliff Spatio-Temporal Erosion on Wolin Island Using ALS Data Analysis

The aim of the article is to present the temporal and spatial variability of the cliff coast erosion of the Wolin Island in 2012–2020 in three time periods (2012–2015, 2015–2018, 2018–2020). The research used data from airborne laser scanning (ALS), based on which DEM models were made. Based on the differences between the models, the amount of sediment that was eroded by the sea waves was determined. The conducted research showed that, in the analyzed period, the dynamics of the Wolin cliffs were characterized by high variability. The greatest erosion was observed on sandy cliffs, and the smallest on clay cliffs and on cliffs that are densely covered with vegetation. In the sediment budget studies, two seashore erosivity indicators were proposed: length-normalized sediment budget (LB) (m3/m) and area-normalized sediment budget (AB) (m3/m2). The average annual dynamics of the cliff edge erosion on the Wolin Island was found to be LB = 6.6 ± 0.3 m3/m/a, AB = 0.17 ± 0.01 m3/m2/a. The results obtained are comparable with other postglacial cliffs. The use of the differential analysis of DEM models allows for the determination of the dynamics of the cliff coast and may be used in spatial development and planning of seashore protection zones.

Soil erosion in Qilian Mountain National Park: Dynamics and driving mechanisms

Study regionQilian Mountain National Park (QLMNP) in northwestern China. Study focusThe risk of soil erosion has increased noticeably at the global scale. In China, several ecological projects have been conducted to minimize the side effect of soil erosion in recent decades. Assessing soil erosion and identifying driving mechanisms are necessary due to the increased risk of ecological security in QLMNP. Here, we employed the Revised Universal Soil Loss Equation (RUSLE) to assess the soil erosion rate in QLMNP from 1982 to 2020. The driving mechanism was detected through the differences between the realistic scenario and four idealized scenarios with different fixed RUSLE input parameters. The contributions of different driving factors (soil type, digital elevation model, slope, extreme precipitation frequency and intensity, precipitation, vegetation coverage, and land use/cover change (LUCC)) were assessed through the geodetector model. New hydrological insights for the regionThe soil erosion rate averaged over QLMNP increased at 0.13 t ha-1 yr-1 from 1982 to 2020, despite the slightly decrease shown in the majority (62.62%) area. Anthropic LUCC in eco-conservation measures tends to prevent soil erosion in QLMNP, but extreme precipitation has the opposite effect. The coupled impacts of extreme precipitation and LUCC dominate the soil erosion dynamics in this area. Our results indicate that ecological projects are effective to mitigate the soil erosion caused by climate change.

Diachronic mapping and evaluation of soil erosion rates using RUSLE in the Bouregreg River Watershed, Morocco

Soil erosion has been severely affecting soil and water resources in semi-arid areas like the Mediterranean. In Morocco, this natural process is accelerated by anthropogenic activities, such as unsustainable soil management, overgrazing, and deforestation. With a drainage area of 395,600 ha, the Bouregreg River Watershed extends from the Middle Atlas Range (Jebel Mtourzgane) to the Sidi Mohamed Ben Abdellah (SMBA) dam reservoir south-east of Rabat. Its contrasted eco-geomorphological landscapes make it susceptible to unprecedented soil erosion due to climate change. Resulting changes in erosive dynamics led to huge amounts of solid loads transported to the catchment outlet and, thus, jeopardised the SMBA dam lifespan due to siltation. The research aims to quantify the average annual soil losses in this watershed using the Revised Universal Equation of Soil Losses (RUSLE) within a GIS environment. To highlight shifts in land use/land cover patterns and their effects on erosional severity, we have resorted to remote sensing through two Landsat 8 satellite images captured in 2004 and 2019. The C factor was combined with readily available local data regarding major erosion factors, e.g. rainfall aggressiveness ( R), soil erodibility ( K), topography ( LS), and conservation practices ( P). The helped to map the erosion hazard and determine erosion prone areas within the watershed where appropriate water and conservation measures are to be considered. Accordingly, from 2004 to 2019, average annual soil losses increased from 11.78 to 18.38 t∙ha –1∙y –1, as the watershed area affected by strong erosion (>30 t∙ha –1∙y –1) evolved from 13.57 to 39.39%.

Snowfall and snow accumulation during the MOSAiC winter and spring seasons

Abstract. Data from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition allowed us to investigate the temporal dynamics of snowfall, snow accumulation and erosion in great detail for almost the whole accumulation season (November 2019 to May 2020). We computed cumulative snow water equivalent (SWE) over the sea ice based on snow depth and density retrievals from a SnowMicroPen and approximately weekly measured snow depths along fixed transect paths. We used the derived SWE from the snow cover to compare with precipitation sensors installed during MOSAiC. The data were also compared with ERA5 reanalysis snowfall rates for the drift track. We found an accumulated snow mass of 38 mm SWE between the end of October 2019 and end of April 2020. The initial SWE over first-year ice relative to second-year ice increased from 50 % to 90 % by end of the investigation period. Further, we found that the Vaisala Present Weather Detector 22, an optical precipitation sensor, and installed on a railing on the top deck of research vessel Polarstern, was least affected by blowing snow and showed good agreements with SWE retrievals along the transect. On the contrary, the OTT Pluvio2 pluviometer and the OTT Parsivel2 laser disdrometer were largely affected by wind and blowing snow, leading to too high measured precipitation rates. These are largely reduced when eliminating drifting snow periods in the comparison. ERA5 reveals good timing of the snowfall events and good agreement with ground measurements with an overestimation tendency. Retrieved snowfall from the ship-based Ka-band ARM zenith radar shows good agreements with SWE of the snow cover and differences comparable to those of ERA5. Based on the results, we suggest the Ka-band radar-derived snowfall as an upper limit and the present weather detector on RV Polarstern as a lower limit of a cumulative snowfall range. Based on these findings, we suggest a cumulative snowfall of 72 to 107 mm and a precipitation mass loss of the snow cover due to erosion and sublimation as between 47 % and 68 %, for the time period between 31 October 2019 and 26 April 2020. Extending this period beyond available snow cover measurements, we suggest a cumulative snowfall of 98–114 mm.

Two Millennia of Complexity and Variability in a Perialpine Socioecological System (Savoie, France): The Contribution of Palynology and sedaDNA Analysis

Over the last two millennia, European Alpine ecosystems have experienced major changes in response to the important, yet fluctuating, impact of human activities. This study aims to reconstruct the environmental history of the last 1800 years on the western edge of the Alps by analyzing sediments from Lake Aiguebelette, a large lake located in the perialpine area. We have combined analyses of pollen and other palynomorphs, such as coprophilous fungal spores, together with sedimentary DNA (from plants and mammals) in order to reconstruct both vegetation and land-use histories. A sedimentological and geochemical analysis was also conducted in order to gain an understanding of changes in erosion dynamics in response to landscape modifications that were influenced by climate and human activities. This work highlights alternating phases of anthropization and agricultural abandonment allowing forest recovery. While pollen reflects the major phases of regional deforestation and afforestation related to the dynamic of farming activities, plant DNA provides precise information on the plants cultivated in fields, orchards and vegetable gardens over the past centuries. The combination of mammal DNA and coprophilous fungal spores completes this work by documenting the history of pastoral practices.

Temporal Evolution of Erosion in Pore Networks: From Homogenization to Instability.

We study the dynamics of flow networks in porous media using two and three dimensional pore-network models. We consider a class of erosion dynamics for a single phase flow with no deposition, chemical reactions, or topology changes assuming a constitutive law depending on flow rate, local velocities, or shear stress at the walls. We show that depending on the erosion law, the flow may become uniform and homogenized or become unstable and develop channels. By defining an order parameter capturing these different behaviors we show that a phase transition occurs depending on the erosion dynamics. Using a simple model, we identify quantitative criteria to distinguish these regimes and correctly predict the fate of the network, and discuss the experimental relevance of our result.

ULTRA-HIGH RESOLUTION MAPS AND MODELS AS TOOLS FOR MANAGING AND MONITORING ENVIRONMENTALLY SENSITIVE GEOSITES (ESTRELA UNESCO GLOBAL GEOPARK, PORTUGAL)

Abstract. This paper focuses on the interpretation of the natural components presents at different geosites in the Estrela UNESCO Global Geopark and on the analysis of soil erosion dynamics associated with trampling events in recent years. Three areas were evaluated: Salgadeiras - Covão da Clareza, Lagoa Seca and Covão do Boi. On there, UAV photogrammetry surveys were applied to obtain orthomosaics and dense clouds that then were used like background at the successive steps of the analysis. The high resolution of the point cloud and orthomosaics allowed us to identify and cartography the geology, hydrography, and vegetation features presents in each place. Besides all trampling sectors were mapped, establishing thus areas potentially vulnerable to environmental degradation because of walk-induced erosion. The analysis presented at this work evidenced an increase in the trampling areas in all the geosites considered, evidencing the potential of this tool like support for future sustainable management of protected areas.This research was supported by the Foundation for Science and Technology (FCT) within the scope of the project Avaliação de sistemas aéreos inteligentes de baixo-custo para mapeamento 3D da superficies of terrene (PTDC/EAM-REM/30475/2014) and by Estrela UNESCO Global Geopark.