The software LandLord is developed for digital terrain modelling.
Initial data are digital elevation models (DEMs) based on plane square grids or spheroidal equal angular grids.
The software LandLord 4.0 allows one to carry out the following procedures:
· Derivation of digital models of local topographic attributes. Four methods can be used to process DEMs given by a plane square grid: the Evans–Young method, the Zevenbergen–Thorne method, the Shary method, and the author’s method. Another author's method can be used to derive partial derivatives from DEMs given by a spheroidal equal angular grid. The following morphometric characteristics describing local topography can be calculated:
§ All variables of the complete system of curvatures: horizontal curvature, vertical curvature, mean curvature, Gaussian curvature, accumulation curvature, ring curvature, unsphericity curvature, difference curvature, minimal curvature, maximal curvature, horizontal excess curvature, and vertical excess curvature.
§ Solar morphometric variables: insolation and reflectance.
· Derivation of digital models of nonlocal topographic attributes. The Martz–De Jong method is used to process DEMs given by a plane square grid. This method adapted to the geometry of the convex spheroidal equal angular grid is used to process DEMs given by a spheroidal equal angular grid. The following geomorphometric characteristics describing regional topography can be calculated:
§ Minimal and maximal catchment area.
§ Minimal and maximal dispersive area.
§ Minimal and maximal topographic index.
§ Minimal and maximal stream power index.
· Smoothing of digital models given by square-spaced and spheroidal trapezoidal grids:
§ Weighted average smoothing using 3x3, 5x5, and 7x7 kernels.
§ Calculating depression-free DEMs by the Martz–De Jong method.
· Conventional arithmetic procedures: addition, subtraction, multiplication, division, logarithms, exponent, and Laplasian, as well as area and volume estimation.
· Statistical analysis:
§ Derivation of linear regression-based digital models of natural properties using topographic attributes as independent variables in corresponding regression equations.
§ Estimation of root mean square errors (RMSE) for all variables of the complete system of curvatures as well as slope steepness, slope aspect, plan curvature, rotor, and derivating function derived from DEMs given by square-spaced and spheroidal trapezoidal grids.
· Visualization of DTMs using several colour and grey scales (examples can be found in publications).
· Import of Surfer binary files *.grd
· Import of quasi-global and global DEMs ETOPO1, ETOPO2, ETOPO5, GLOBO, GTOPO30, SRTM30, SRTM30_PLUS, IBCAO, IBCSO, SRTM3, SRTM1, and ASTER GDEM archives, as well as planetary DEMs from NASA PDS archives.
· Export of LandLord DTM files into plain text files, ArcInfo text files *.asc, and Surfer binary files *.grd.
Availability and distribution
I do not distribute the software. A collaborative research with a subsequent joint publication is the only possibility to use LandLord 4.0.
For details and examples, see: