Landscape Mosaic (GWB_LM)#

This module conducts the Landscape Mosaic analysis at up to 10 user-selected observation scales. The Landscape Mosaic measures land cover heterogeneity, or human influence, in a tri-polar classification of a location accounting for the relative contributions of the three land cover types Agriculture, Natural, Developed in the area surrounding that location. The result are spatially explicit maps and tabular summary statistics. Details on the methodology and input/output options can be found in the Landscape Mosaic product sheet.

Requirements#

A single band (Geo)TIFF image in data format byte:

  • 0 byte: missing (optional)

  • 1 byte: Agriculture

  • 2 byte: Natural

  • 3 byte: Developed

Warning

Input image values > 3 byte will be considered as missing data

Processing parameter options are stored in the file input/lm-parameters.txt.

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; GWB_LM parameter file:
;; NOTE: do NOT delete or add any lines in this parameter file!
;;
;; LM will provide up to 10 images and summary statistics.
;; Please specify entries at line 14 ONLY using the following options:
;; line 14: kdim: up to 10 window sizes (unit: pixels, uneven within [3, 501] ) in increasing order and separated by a single space.
;;          obs_scale [hectare] = (pixres[m] * kdim)^2 / 10000
;;
;; example parameter file
;; (assuming a pixel resolution of 30m, a 11x11 window ~ 10.9 ha):
;; 11
****************************************************************************
23
****************************************************************************

Example#

The results are stored in the directory output, one directory for each input image accompanied by a log-file providing details on computation time and processing success of each input image.

GWB_LM command and listing of results in the directory output:

$ GWB_LM -i=$HOME/input -o=$HOME/output
IDL 9.1.0 (linux x86_64 m64).
(c) 2024, NV5 Geospatial Solutions, Inc.

GWB_LM using:
dir_input= $HOME/input
dir_output= $HOME/output
% Loaded DLM: TIFF.
% Loaded DLM: PNG.
Done with: clc3class.tif
Done with: example.tif
Done with: gscinput.tif
LM finished sucessfully

$ ls -R output/
output/:
clc3class_lm_23  example_lm_23  lm23.log

output/clc3class_lm_23:
clc3class_lm_23_103class.tif  clc3class_lm_23_heatmap.png   clc3class_lm_23.tif
lm103class_legend.png         clc3class_lm_23_heatmap.csv   clc3class_lm_23_heatmap.sav
heatmap_legend.png

output/example_lm_23:
example_lm_23_103class.tif  example_lm_23_heatmap.png   example_lm_23.tif
lm103class_legend.png       example_lm_23_heatmap.csv   example_lm_23_heatmap.sav
heatmap_legend.png

Example statistics (heatmap) and spatial result of the custom-scale analysis of the input image clc3class.tif, showing the degree of predominance of land cover types Agriculture, Natural, Developed.

../_images/clc3class_lm_23_heatmap.png ../_images/clc3class_lm_23.tif

Remarks#

  • The IDL-specific sav-file can be used in GTB to conduct LM change analysis.

  • LM is not restricted to Ag, Nat, Dev but can be applied to any 3 types of dominant land cover.

  • The result provides the LM analysis for a single custom observation scale. In the example above, and assuming a pixel resolution of 100 meter, an observation scale of 23x23 pixels corresponds to a local neighborhood (analysis scale) of 2300x2300 meters ~ 50 hectare.

  • The heatmap facilitates assessments of temporal changes and/or comparison between different sites.

The Landscape Mosaic has been used to map and summarize the degree of landscape heterogeneity in many occasions (see references in the Landscape Mosaic product sheet), including the RPA, Embrapa, and MAES reports.