Table 1 Predictor variables.

Slope

The measure of surface inclination, typically expressed in degrees or percentages. It is derived from the DTM and is used to classify topographic parameters and identify areas with a higher frequency of landslides, playing a crucial role in assessing terrain stability and landslide risks^51,52,53.

DTM⁵⁴

Aspect

The azimuthal orientation of the slope influences the incidence of exogenous factors such as sunlight, wind, and rainfall. This variable directly affects weathering, vegetation cover, and the hydrological dynamics of the slope, conditioning its susceptibility to mass movements⁵⁵.

DTM⁵⁴

Elevation

This represents the altitude of a point in relation to sea level (topographic elevation) or the difference in altitude between relief features (relative elevation). This variable affects water pressure in the soil, surface runoff, and gravitational potential energy, consequently affecting slope stability and the likelihood of landslides⁵⁶.

DTM⁵⁴

Plan curvature

This refers to the rate of change of the flow direction \((\varphi + \pi )\) along the direction of the vector \(\left( \frac{\nabla ^\perp f}{S}\right)\), i.e., following a contour line. In the context of landslides, this curvature indicates how the terrain curves laterally, affecting the dispersion of surface flow and soil stability⁵⁶.

DTM⁵⁴

Profile curvature

The rate of change of the surface slope along the direction of the unit vector \((-\nabla /S\)), i.e., following the flow line in a downward direction. In the context of landslides, this measure indicates how the terrain curves towards the flow, affecting the accumulation and dynamics of water and sediment⁵⁷.

DTM⁵⁴

Convergence Index

This metric assesses the slope curvature by calculating the average of the slope directions of neighboring pixels in relation to the direction of the central pixel. In the context of landslides, negative values indicate convergent areas favoring the accumulation of water and materials, while positive values represent divergent areas, where surface flow is dispersed, influencing the potential for soil instability^58,59,60.

DTM⁵⁴

Relative slope position

This represents the ratio the slope height to the elevation difference, measured from the ridge or summit to the valley floor, and describes the topographical position of the terrain. This variable is crucial for landslide analysis, as it helps to identify areas of greater susceptibility based on the terrain’s relative position, influencing processes such as water accumulation, sediment dynamics, and soil stability^61,62.

DTM⁵⁴

Terrain Ruggedness Index (TRI)

This measures of the variation in elevation between a cell and its neighbors in a DTM, reflecting topographic roughness. This index is crucial for landslide analysis, as areas with greater roughness tend to have a higher risk of instability^63,64.

DTM⁵⁴

Topographic Wetness Index (TWI)

This quantifies soil moisture variation by integrating upstream water supply and downstream runoff in a DTM. It combines the slope gradient with the specific catchment area. TWI is crucial for landslide analysis, as areas with higher soil moisture face a greater risk of instability^65,66.

DTM⁵⁴

Distance to rivers

This refers to the Euclidean (straight-line) distance to water bodies. It is a critical factor for landslide analysis, as proximity to water bodies can increase the risk of slope erosion and soil saturation. Most landslides occur in areas close to rivers, particularly within a 200-meter radius. This variable should be incorporated into risk models to accurately identify high-risk zones^67,68.

IBGE⁶⁹

Land cover

The physical characteristics of the Earth’s surface, such as vegetation, water bodies, and built structures. It describes the natural and human-made features that occupy a specific area. Land cover plays an important role in landslide analysis, as it influences soil stability, water retention, and slope stability, helping to identify areas at higher risk for landslides^9,70.

Marques-Carvalho et al. (2025)⁷¹

Lithology

This refers to physical and mineralogical characteristics of sediments and rock types within the Earth’s stratigraphy. It is crucial in landslide studies, as it influences spatial variation in landslide prevalence, type, and depth by affecting properties such as porosity, permeability, and water saturation, which determine soil and rock stability^72,73.

SGB (2017)⁷⁴

Geomorphology

Land relief is the shape and structure of the earth’s surface resulting from geomorphological processes involving endogenous forces (such as faults and folds) and exogenous forces (such as climate, gravity, water, wind and ice), which are responsible for the continuous shaping and transformation of the terrain^75,76.

SGB (2017)⁷⁴

Pedology

This influences slope stability and is determined by texture and clay content. Clay soils, such as andosols, latosols, and organosols, tend to retain more water, increasing the risk of landslides, whereas sandy soils, such as regosols, are more permeable, reducing this risk^77,78.

SGB (2017)⁷⁴

Rainfall

Heavy rainfall alters the dynamics of surface and groundwater, reducing soil stability and triggering landslides. This occurs due to increased soil saturation and a decrease in particle cohesion^79,80.

SGB (2017)⁷⁴

Distance to roads

Influences landslide susceptibility due to soil disturbances caused by cut-and-fill works, changes in drainage, and unplanned human activities. Traffic vibrations can weaken slope materials, compact the soil, and increase the risk of instability⁸¹.

DataGEO (2013)⁸²