CICEI TC31

Biomes of South America: South American terrestrial biomes as geocomplexes: a geobotanical landscape approach

The classic and current conception of biome in its various meanings is fundamentally based on vegetation types that are considered as discrete or independent and fragmented entities in the landscape. Vegetation units are characterized by their physiognomy, which is based on the dominant life forms, and mainly determined by climatic conditions. However, vegetation units are associated and mutually interacting at a landscape level. They are determined by local or regional, climatic, topographic and edaphic gradients within a given territory or geographic area. In this work, we propose a new conceptual and methodological approach aiming at better understanding of the biome concept in a landscape framework, developing ideas already partially advanced by us. In this sense, we consider the biome as a landscape complex (geocomplex), that spatially includes one to several vegetation geoseries which, in turn, are each made up by the possible following geomorphologically linked vegetation series:

• The potential natural climatophilic vegetation (zonal vegetation) and their seral successional stages with which it is repeatedly associated in the landscape;

• Edapho-xerophyllous vegetation (azonal vegetation as rocky outcrops or sandy soils); and

• Edapho-hygrophilic vegetation (intrazonal vegetation such as flooded vegetation in river banks). Based on the surveys and field data (more than ca. 300 transects) obtained by the authors in most South American countries from 1990 to the present, 33+ South American geocomplex biomes and sixteen macrobiomes were identified and synoptically characterized, through graphic general zonation models (phyto-topographic type-profiles) extrapolated from numerous observations along representative bioclimatical, geomorphological and biogeographically stratified transects.

Participantes: Gonzalo Navarro, Federico Luebert, José Antonio Molina
Inicio 2022
Cierre 2023