Modelling bryophytes distribution pattern using environmental parameters of Iran in Geographical Information Systems (GIS): a case study of three genera Tortula, Grimmia and Bryum (Bryophyta)

In the present study, a modelling approach based on geographical information systems (gis) analysis is presented with the aim of identifying the influence of environmental parameters on three genera, namely, tortula, grimmia and bryum as representatives of iranian bryoflora. by using arcgis desktop, we produced a model for environmental variables include altitude, precipitation, temperature and humidity. to test the model, we surveyed the effect of selected geographical and environmental variables including altitude, latitude, annual mean precipitation, maximum, minimum, and mean temperatures and humidity on distribution pathern of these three genera. within 108 localities, 52 samples of bryum (48%), 33 samples of grimmia (30%) and 24 samples of tortula (22%) were recorded. the digital models that we achieved revealed interesting results. altitude map shows strong preference within three genera for mountainous regions. almost all species limited to the regions received proper amount of average rainfall. temperature digital map shows a negative relationship between temperature and bryophytes distribution. modelling the four environmental parameters of iran provides the means for a quantitative analysis of the distribution and abundance of vegetation types in every selected area, thus also allowing quantification and prediction of environmental effects on vegetation distribution. it stimulates the use of gis in botanical investigations by putting a collection of free, relevant, high quality formatted data into the hands of botanical researchers.