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Abstract As an important topographic attribute widely-used in precision agriculture, topographic wetness index (TWI) is designed to quantify the effect of local topography on hydrological processes and for modeling the spatial distribution of soil moisture and surface saturation. This index is formulated as TWI = ln(a/tanb), where a is the upslope Proxies quantifying water accumulation may have suitable properties because hydromorphy partly determines plant and animal communities. Topographic wetness index (TWI) was developed to locate wetlands but has largely been ignored from ecological studies despite the value of these areas for biodiversity and the ecosystem services they provide. We assessed here the ability of TWI to predict the occurrence of grassland passerines and tested different settings to determine which was A variety of landscape properties have been modeled successfully using topographic indices such as topog-raphic wetness index (TWI), defined as ln(a/tanβ), where a is the specific upslope area and is the surface β slope. In this study, 25 m spatial resolution from digital elevation models (DEM) data were used to investi- Topographic Wetness Index (TWI) quantifies terrain driven variation in soil moisture. • TWI can be calculated with different flow-routing, slope and flow width algorithms. • We compared these algorithms against measured soil moisture and plant composition. • TWI algorithm determines TWI ability to predict soil moisture and plant assemblages. • Methods: The topographic wetness index, an estimate of predicted water accumulation in a defined area, was generated from a digital terrain model of the landscape surrounding households in two neighbouring western Kenyan highland communities. Variables determined to best encompass the variance in this topographic wetness surface were calculated at a household level. Land-cover/land-use Topographic Wetness Index and Prehistoric Land Use Abstract: A digital terrain model (DTM) of an area of approximately 100 km2 in East Jutland, Denmark, has been created based on information from the oldest available topographic map from the second half of the 19th century. On the basis of this model, a topographic wetness index for a 10 x 10 m cell grid has been Topographic Wetness Index (TWI) and Terrain Ruggedness Index (TRI) are secondary geo- morphometric parameters used to describe and quantify local relief. In this paper their usefulness in geomorphological studies of landslides is explored. Using a sample of twelve objects from the Sudetes, SW Poland, spatial and statistical distributions of TWI and TRI values are presented and discussed. Both TWI and TRI prove capable of differentiating landslide population into smaller groups s so that the soil-topographic wetness index (STWI) can be expressed as ln(a/(D·K s·tanβ)). The logarithm function in the TWI formula that illustrates an exponential decline of the soil transmissivity with depth can also be changed so as to portray linear or parabolic declines (Ambroise et al., 1996a; Duan and Miller, 1997). However, it was pre