Cartographie des facteurs écologiques et de la population de marmottes dans la réserve du Mont Vallier (Ariège). Mapping ecological factors and marmot population in Mont Valier Nature Reserve, Pyrenees, France.

Résumé

The aim of this programme, written in BASIC, is to draw symbolic representation of data on previously drawn maps. The original map, obtained by use of a drawing progamme (such as Mac Draw or Canvas), is in a Pict file, with maximal dimensions of 240x240 mm. Data, which represent an array having n1 columms (variables or presence-absence of some characteristics) and n2 rows (longitudes for instance), are stored in a text file. Each cell of the array corresponds, for instance, to a 200 x 200 meter quadrat in the field, which could be represented as a 4x4mm square on the map (scale: 1/50,000). The square could be black or white or inbetween, according to the value of the variable corresponding to the column. Three predefined scales for the squares are available and one other scales can be defined. Presentation of data can be realized in black and white or in colors, under each option either with variation of intensity or symbols. Eight different densities of points can be used in black and white presentation and two tints, a background colour and a forecolour, with 8 possible colour (white, black, red, blue, yellow, magenta and cyan) and with 5 possible gradations of the background colour, in coloured presentation. In both cases (black and white or colours), presence-absence can be represented with symbols (a marmot for instance in the quadrat where marmots are found. The symbol must be in a Pict file. The map is drawn on the screen and can be printed and/or saved in a Pict file and can be modify using Mac Draw for instance. This programme has been run to study the characteristic parameters of the spatial distribution of the marmot population of Mont Valier.