Search Results (41)

Estimating in a stream’s cross-section the depth-averaged velocity, V, from the free-surface velocity, v_surf, is an efficient, non-invasive hydrometric method. The ratio f_v = V/v_surf is typically assumed constant at f_v = 0.86 in field applications, despite observations to the contrary. Guidance is, therefore, needed in estimating actual f_v-ratios when velocity profile data are absent. This work provides field-verified guidance based on the hydromechanics of the logarithmic velocity law, which shows that f_v depends on the scaled resistance measure ‘friction length/depth’, y_o/h, with the y_o(k) function of the equivalent sand grain roughness, k. The mean-to-surface-velocity ratio in rough-bed streams is estimated from the bed roughness and stream morphology by modifying Nikuradze’s equation, y_o = k/30, to y_o = ck, with c(h/k) ≥ 1/30, and k ≈ D₈₄—data fit: c ≈ 8.61(h/k)^−1.821, ~5 ≤ h/k < ~30. Field-verification of the ratio’s modified hydromechanics, f_v = f$\left(h/y_o\right),$ with y_o(h/k) evaluated from bed roughness estimated by inspection or sieve analysis shows this ratio holding within ~|10|% error for shallow streamflow over a coarse bed of gravels and rocks, giving submergences of ~5 ≤ h/D₈₄ ≤ ~30; y_o = k/30 suits large streams with smooth beds (h/k ≥ ~30, f_v ≥ ~0.86). Variable roughness-estimated f_v-ratios appear to be more reliable than the fixed default, f_v(h/y_o ≈ 1000) = 0.86. This flow-gauging concept is based on observable physical characteristics of a monitoring cross-section and facilitates the rating of hard-to-access streams draining small basins in ragged upland terrain. Full article

The catastrophic impact of Hurricane Helene proved that standard FEMA flood maps are often inadequate for assessing risk in complex mountainous terrain. Using Buncombe County, North Carolina, as a case study, this research introduces a replicable framework for siting emergency shelters based on a multi-dimensional Flood Risk Index. By synthesizing HAND-derived inundation data, land-use intensity, and a machine learning-based Socio-Economic Vulnerability Index (SEVI), we mapped the intersection of hazard and vulnerability. Our analysis reveals a significant misalignment—a large portion of the current shelter network sits in high-risk zones, while safer upland corridors in the north and west remain underutilized. This study delivers a data-driven roadmap for disaster preparedness, ensuring that future shelter placement is not only safe from terrain-driven floods but also strategically and equitably located. Full article

This paper presents the results of assessing the influence of siltation factors in 23 ponds in one of the most agriculturally developed macro-regions of European Russia—the Central Russian Upland. Key natural and anthropogenic factors determining the intensity of pond siltation have been identified, and a typification of ponds has been developed to predict the rate of accumulation of bottom sediments in them. For the typification, statistical methods such as correlation analysis (Spearman’s coefficient), cluster and factor analysis, and the Random Forest machine learning algorithm were used. Correlation analysis revealed that the percentage of catchment cultivation has a significant effect (r = 0.55, p < 0.01) on the volume of bottom sediments, while soil loss (r = 0.47, p < 0.05) and vertical terrain dissection (r = 0.43, p < 0.05) have a moderate effect. The most important factors in the siltation process are the average slope of the catchment (24.5%), the percentage of cultivated soils (18.8%), and the average annual soil loss (14.1%). All factors were grouped into three clusters, which explained 77.8% of the variance. As a result, four pond types were identified, differing in their dominant limiting factors: pond hydrological characteristics, catchment morphometry, and the degree of anthropogenic transformation of the catchment. Verification of the typification was carried out based on the calculation of annual soil losses considering the sediment delivery coefficient; the discrepancies between the calculated and actual pond sediment volumes were 1.2–10.0%. The proposed approach, which recommends a multi-scale assessment of potential sediment formation volumes using remote sensing data and thematic mapping, offers heuristic potential for identifying the most degraded water bodies. This enables the planning of priority sites and rehabilitation measures for their restoration within the framework of regional soil and water conservation programs. Full article

Mountain forests play a key role in buffering local climate, yet their climate sensitivity is seldom mapped in a way that is directly usable for spatial planning. This study investigates how phenological thermal and vegetation variability are organized within the forested landscape of Namyangju, a mountainous region in central Korea, and derives spatial indicators of forest climate sensitivity. Using monthly, cloud-screened Landsat-8/9 land surface temperature (LST) and normalized difference vegetation index (NDVI) images over a recent multi-year period, we calculated phenological coefficients of variation for 34,123 forest grid cells and applied local clustering analysis to identify belts of high and low variability. Forest areas where LST and NDVI variability simultaneously occupied the upper tail of their distributions (top 5%/10%/20%) were interpreted as climate-sensitivity hotspots, whereas co-located coldspots were treated as microclimatic refugia. Across the mountainous terrain, sensitivity hotspots formed continuous belts along high-elevation ridges and steep, dissected slopes, while coldspots were concentrated in sheltered valley floors. Notably, the most sensitive belts were dominated by high-elevation conifer stands, despite the limited seasonal fluctuation typically expected in evergreen canopies. This pattern suggests that elevation strongly amplifies the coupling between thermal responsiveness and vegetation health, whereas valley-bottom forests act as stabilizers that maintain comparatively constant microclimatic and phenological conditions. We refer to these patterns as “forest climate-sensitivity belts,” which translate satellite observations into spatially explicit information on where climate-buffering functions are most vulnerable or resilient. Incorporating climate-sensitivity belts into forest plans and adaptation strategies can guide elevation-aware species selection in new afforestation, targeted restoration and fuel-load management in upland sensitivity zones, and the protection of valley refugia that support biodiversity, thermal buffering, and hydrological regulation. Because the framework relies on standard satellite products and transparent calculations, it can be updated as new imagery becomes available and transferred to other seasonal, mountainous regions, providing a practical basis for climate-resilient forest planning. Full article

Analyses of thermokarst hazard risk are becoming increasingly crucial in the context of global warming. A significant aspect of thermokarst research is the mapping of landscapes based on their vulnerability to thermokarst processes. The exponential growth of remote sensing data and the advent of novel techniques have paved the way for the creation of sophisticated techniques for the study of natural disasters, including thermokarst phenomena. This study applies machine learning techniques to assess the vulnerability of tundra landscapes to thermokarst by integrating supervised classification using random forest with morphometric analysis based on the Topography Position Index. We recognized that the thermokarst landscape with the greatest potential for future permafrost thawing occupies 20% of the study region. The thermokarst-affected terrains and water bodies located in the undegraded uplands account for 13% of the total area, while those in depressions and valleys account for 44%. A small part (6%) of the study region represents areas with stable terrains within depressions and valleys that underwent topographic alterations and are likely to maintain stability in the future. This approach enables big geodata-driven predictive modeling of permafrost hazards, improving thermokarst risk assessment. It highlights machine learning and Google Earth Engine’s potential for forecasting landscape transformations in vulnerable Arctic regions. Full article

Assessing the spatio-temporal variability and driving forces of soil erosion on the Loess Plateau is critical for ecological and environmental management. In this paper, the Revised Universal Soil Loss Equation (RUSLE) model, the patch-generating land use simulation, and the Geographical Detector are used to investigate the spatio-temporal variations of the Loess Plateau’s soil erosion from 2000 to 2050. The results showed that: (1) The primary categories of soil erosion from 2000 to 2020 were moderate, mild, and slight, and the average level of soil erosion exhibited a decreasing and then an increasing tendency during the last 20 years. (2) Soil erosion was directly impacted by changes in land use, with cropland and forest being the primary land use and land cover changes in the study region. Cropland and construction land being turned into woodland between 2000 and 2020 resulted in a significant decrease in the severity of soil erosion. Projected soil erosion is expected to increase significantly between 2020 and 2050 due to arable land being converted into construction land. (3) The key variables impacting the spatial distribution of soil erosion were LUCC (Land-Use and Land-Cover Change), NDVI (Normalized Difference Vegetation Index), and slope, and the interplay of these variables may increase their ability to explain soil erosion. Grasslands with an NDVI ranging from 0.9 to 1, rain ranging from 0.805 to 0.854 m, a slope above 35°, and a terrain elevation ranging from 1595 to 2559 m were identified as having a high risk of soil erosion. Soil erosion prevention and management efforts should focus on the ecological restoration of upland areas in the future. Full article

The nutritional composition of bovine liver, particularly in terms of vitamins E, β-carotene, and cholesterol concentration, is significantly influenced by the cattle-rearing system and diet. This study aimed to elucidate the impact of four predominant cattle-rearing systems in the Eastern Amazon region on the vitamin E, β-carotene content, and cholesterol levels in bovine liver during the rainy season. Liver-tissue samples were collected from 48 cattle, with twelve specimens representing each rearing system. The systems encompassed two native pastures located in flood-prone areas, cultivated pastures on upland terrain and a confinement-rearing system. Our findings indicate that, when considering all rearing systems collectively, there were no significant differences in the levels of vitamins and cholesterol in the liver tissues (p > 0.05). However, a marked disparity in cholesterol levels emerged when comparing intensive rearing systems to extensive ones, with the former demonstrating notably higher concentrations (p = 0.01). Additionally, the intensive rearing system was associated with elevated levels of β-carotene (p < 0.01), α-tocopherol (p = 0.01), and β-tocopherol (p = 0.01) relative to the extensive systems. No significant variations were observed amongst the different extensive systems (p > 0.05). These results suggest that, while all rearing systems yielded liver tissues with typical concentrations of vitamins and cholesterol, the intensive rearing system led to a higher accumulation of certain vitamin compounds. This study highlights the substantial nutritional implications of different cattle-rearing systems in the Eastern Amazon and provides valuable insights for developing dietary strategies to optimize the nutritional quality of bovine liver. Therefore, the generated results are groundbreaking in the Eastern Amazon, Brazil, and inspire the development of new research projects to address other demands in this field and achieve additional outcomes. Full article

Vehicles often experience low tire pressures and high torques in off-road operations, making tire–rim slip likely. Tire–rim slip is undesirable relative rotation between the tire and rim, which, in this study, is measured by the relative tire–rim slip rate. There is little research on the effect of different terrains on tire–rim slip despite its significance for off-road driving; therefore, this topic was explored through Finite Element Analysis (FEA) simulations. An upland sandy loam soil was modelled and calibrated using Smoothed-Particle Hydrodynamics (SPH), and then a Regional Haul Drive (RHD) truck tire was simulated driving over this terrain, with a drawbar load added to increase drive torque. To examine their effects, five parameters were changed: tire–rim friction coefficient, longitudinal wheel speed, drawbar load, vertical load, and inflation pressure. The simulations showed that increasing the tire–rim friction coefficient and the inflation pressure decreased the tire–rim slip while increasing the vertical and drawbar loads increased the tire–rim slip. Varying the longitudinal wheel speed had no significant effect. Tire–rim slip was more likely to occur on the soil because it happened at lower drawbar loads on the soil than on the hard surface. These research results increased knowledge of tire–rim slip mechanics and provided a foundation for exploring tire–rim slip on other terrains, such as clays or sands. Full article

Geoparks are territorial organizations, whose primary aim is to foster sustainable local development through the promotion of geoheritage, geotourism and geoeducation. Sites of significant interest from the perspective of geosciences (geosites), as well as the overall geodiversity of the territory, are the fundamental resources for geopark activities. The distribution of these resources in the geographical space of geoparks may, however, be uneven. We first review four cases of UNESCO Global Geoparks from different European countries (Czechia, Germany, Hungary, Portugal) where such a situation occurs, with consequences on tourism development. Then, we place particular focus on an aspiring geopark of the Land of Extinct Volcanoes in SW Poland, providing evidence of its geoheritage and geodiversity values. The aspiring geopark integrates a mountainous–upland terrain and a lowland part, the latter with much fewer sites of interest and, apparently, fewer opportunities to successfully develop geotourism. Recognizing the challenges emerging from the non-uniform distribution of resources and learning from established geoparks, we highlight various opportunities to encourage (geo)tourism in the less diverse sections of the geoparks. Implementation of the ABC (abiotic–biotic–cultural) concept could be particularly helpful, as could be various events organized in these areas. Full article

In recent years, many developing countries have consolidated rural primary schools, closed small community schools, and enlarged centralized schools, which can reduce the accessibility of education to many communities. Meanwhile, expanding road networks may enable people in far-flung communities to access schools more easily. To evaluate the impacts of both trends on spatial justice in access to education, it is important to examine spatial patterns of primary school accessibility and their predictors. How do the topographic features of villages and surrounding landscapes correlate with primary school accessibility in rural upland areas? Using a digital map route planning application, this study evaluates the primary school accessibility of each village in Nanjiang County, a mountainous county in southwest China. By evaluating relationships between primary school accessibility and village characteristics, this study provides evidence corroborating frequent claims that rural remote mountainous areas have poor primary school accessibility. Additionally, by analyzing the effects of elevation and ruggedness of villages and of the zone between villages and schools as well as the mechanisms driving these effects, we find that, contrary to expectations, with increasing village elevation, a village’s primary school accessibility first decreases and then increases. The ruggedness of the terrain upon which a village is built has no significant effect. The ruggedness of the zone between a village and its nearest school exerts significant effects. These findings demonstrate that the two policies have created a pattern of spatial injustice that disadvantages peripheral villages, illustrating the need to attend to topography in efforts to provide equitable school access in rural mountainous areas. Full article

The application of the automated analysis of remote sensing data processed into high-resolution digital terrain models (DTMs) using geographic information systems (GIS) tools provides a geomorphometric characterization of the diversity of the relief of loess patches over large areas. Herein, a quantitative classification of 79 loess patches with a total area of 3361 km², distributed within the eastern part of the Polish Uplands belt, is carried out. A high-resolution 1 × 1 m DTM was generated from airborne laser scanning (ALS) data with densities ranging from 4 pts/m² to 12 pts/m², which was resampled to a resolution of 5 × 5 m for the study. This model was used to classify landform surfaces using the r.geomorphon (geomorphon algorithm) function in GRASS GIS software. By comparing the values in the neighborhood of each cell, a map of geomorphometric features (geomorphon) was obtained. The classification and typology of the relief of the studied loess patches was performed using GeoPAT2 (Geospatial Pattern Analysis Toolbox) software. Pattern signatures with a resolution of 100 × 100 m were extracted from the source data grid, and the similarity of geomorphological maps within the signatures was calculated and saved as a signature file and segment map using the spatial coincidence method. The distance matrix between each pair of segments was calculated, and the heterogeneity and isolation of the maps were generated. R system was used to classify the segments, which generated a dendrogram and a heat map based on the distance matrix. This made it possible to distinguish three main types and eight subtypes of relief. The morphometric approach used will contribute to a better understanding of the spatial variation in the relief of loess patches. Full article

The numerical 1-D HEC-RAS modelling tool was supported by the estimation of the sieve curve changes procedure to measure the scale of predicted discharges along a stretch of stream in southern Poland on the Olkusz Upland. The procedure was calibrated in southern Poland on the mountain streams during high-stage events, using a radiotracer application in bedload transport. Particular terrain hypsometry, created by the dissolution of limestone, forced the deep erosion of the river valley bottom; it is here that the current shape of the riverbed of the Prądnik stream is placed. While numerical modelling is widely used in hydraulics, standards have been set for the estimation of flood risk zones; these estimations suggest that the densities of the measured cross-sections are less then optimal, and that the erosive processes are more frequent. This was proved by identifying a number of erosive sections. A new procedure proposed combining the prediction of grain size distribution with hydraulic modelling. Calculations using the estimation of sieve curves, based on the processes of creation and destruction in the armouring layer, have proven to be a challenge for the existing standards of hydraulic modelling. We believe that it is easy to expand the usefulness of the 1D model by utilising its results for this procedure. For the purpose of this type of analysis, dense cross-section measurements are involved, careful modelling is required and a wide range of additional in-field data has to be gathered. For the interpretation of the results, the relation between channel-forming discharge, bankfull discharge, present and critical shear stresses, as well as the mean diameter of the grain size and other estimated sieve curve parameters, were evaluated. Channel-forming discharge is smaller than the bankfull discharge in more than one third of the segment where the erosion process is more frequent and the stability of the riverbed is compromised. Channel-forming discharge was at least twice as high in the stable sections, compared to the erosive section. The presented method will help to find unstable riverbed sections, in order to mitigate the dimension of river training techniques and protect the natural state of the river. While we are in the period of development in this region of Europe, limiting the scope of interference in rivers and streams by applying this method may create an opportunity for the concept of river training close to nature. Full article

The Korean beekeeping industry is continuously declining owing to the aging worker population and a lack of automation. To solve the problem of manual transportation and low automation of transportation tools in Korean apiculture, a multifunctional beekeeping transport loading box was developed by modifying a tracked vehicle developed in previous studies. To ensure the safety of the modified beekeeping vehicle in an apiary, a dynamic analysis of the vehicle in virtual simulation conditions and a field test inside an actual apiary were conducted. Firstly, the TRACK_LM module in multibody dynamics software RecurDyn was used to model the vehicle. Then, the model was analyzed in two use cases (bee frame loading and beehive loading), three geological conditions (clayey soil, dry sand, and upland sandy loam), and two types of terrain (s-turn and 8° slope). Meanwhile, tests under similar conditions were conducted in an actual apiary. The simulation results indicated that the modified beekeeping vehicle operated stably in the simulated agricultural apiary ground (clayey soil and upland sandy loam). The maximum pitch angles in the clayey soil and upland sandy loam conditions were 11.77° and 12.74°, respectively. However, the vehicle cannot operate under dry sand conditions on a slope because it exceeded the calculated maximum angle (34°) during operation. The maximum pitch angle of only 8.8° in the apiary transport experiment proved that the modified beekeeping vehicle could be driven safely in actual apiaries. Moreover, a comparison of the field test results with the simulation results revealed that the field test further verifies the reference value and correctness of the simulation results. Full article

Land development is rapidly occurring on sand-dominant soils that cover substantial areas of the Lower Mekong Basin (LMB). Sands are at risk of degradation on sloping uplands where agriculture is expanding and on lowland landscapes where intensification of cropping is occurring. Sandstone and granitic geology explain the prevalence of sand-dominant textures of profiles in the LMB. However, the sand terrains in uplands of Cambodia and Southern Laos mostly have not been mapped in detail and the diversity of their edaphic properties is poorly understood. On high-permeability sands, lowland rainfed rice crops are drought-prone, while nutrient losses from leaching are also a risk. Furthermore, waterlogging, inundation and subsoil hardpans are significant hazards that influence the choice of crops and forages for lowland soils. Soil acidity, low nutrient status, hard-setting and shallow rooting depth are significant constraints for crops and forages on sands in the lowlands. Land use change in the lowlands to alternative field crops and forages on sands is contingent on their profitability relative to rice, the amounts and reliability of early wet season rainfall, and the amounts of stored water available after harvesting rice. Low soil fertility and soil acidity are limitations to the productivity of farming systems on the sand profiles in uplands, while erosion, low soil organic matter levels and water balance are concerns for their sustainable use. Site-/soil-specific fertilizer and lime management, land suitability assessment and the use of conservation agriculture principles (minimum tillage and crop residue retention) can overcome some of these constraints. Full article

Tree mortality in Sierra Nevada’s 2012–2015 drought was unexpectedly excessive: ~152 million trees died. The relative performance of five drought indices (DIs: SPEI, AI, PDSI, scPDSI, and PHDI) was evaluated in the complex, upland terrain which supports the forest and supplies 60% of Californian water use. We tested the relative performance of DIs parameterized with on-site and modeled (PRISM) meteorology using streamflow (linear correlation), and modeled forest stand NDVI and tree basal area increment (BAI) with current and lagged year DI. For BAI, additional co-variates that could modify tree response to the environment were included (crown vigor, point-in-time rate of bole growth, and tree to tree competition). On-site and modeled parameterizations of DIs were strongly correlated (0.9), but modeled parameterizations overestimated water availability. Current year DIs were well correlated (0.7–0.9) with streamflow, with physics-based DIs performing better than pedologically-based DIs. DIs were poorly correlated (0.2–0.3) to forest stand NDVI in these variable-density, pine-dominated forests. Current and prior year DIs were significant covariates in the model for BAI but accounted for little of the variation in the model. In this ecosystem where trees shift seasonally between near-surface to regolithic water, DIs were poorly suited for anticipating the observed tree decline. Full article