Problems in Classifying and Mapping Vegetation for Ecological Regionalization

Kuechler, A.

Important research carried on currently in ecological regionalization calls for a close look at the role of classifying and mapping vegetation, as both these activities can be of fundamental significance in regionalization. A correlation of classifying and mapping vegetation with ecological regions requires an analysis of vegetation, classifications, regions, and maps. The analysis of vegetation revealed the character of biogeocenoses, plant communities, and continua and, incidentally, made it clear that the correct term for the science of vegetation studies is phytocenology. Problems of vegetation boundaries can develop when continua are compared with transition, this is important in mapping, where the nature and location of boundaries is of major significance. Vegetation is best divided into natural and cultural vegetation and further subdivided on the basis of (1) physiognomy and structure, (2) floristics, (3) community dynamism, and (4) community relations with their respective biotopes. When these units were applied to an analysis of classifications, it developed that a basic distinction must be made between highly flexible, purely descriptive and essentially classless approaches on the one hand, and clearly organized hierarchies on the other. Serious difficulties can arise when a detailed description of vegetation is related with a classification, and an important distinction emerging from these findings is between worldwide and regional classifications. Multiple mapping at large scales evolved into a particularly useful and enlightening method. However, the often demonstrated correlation between phytocenoses and environmental conditions must not lead a researcher to falsely optimistic conclusions, as it may not be applicable in the humid tropics. Aubréville, Poore, Wyatt-Smith, Koriba, Küchler & Sawyer, etc. have illustrated the need for caution in interpreting such correlations. An analysis of some aspects of regions demonstrated that the relationships between vegetation types and biotopes must be clarified before meaningful ecological regions can be established. This need was illustrated with the map and inset maps of the Hunter Valley region in New South Wales, which proved most revealing. The chief problem of maps in ecological regionalization was found to be the map scale. Scale problems can usually be solved without much difficulty, but they be must clearly understood if the results are not to be misleading. The very nature of the biogeocenose implies by definition that the geographical distributions of biocenoses and of biotopes are most intimately related. The various analyses revealed that vegetation may be regarded as a tangible, integrated expression of the biogeocenose. Maps showing the geographical distribution of the natural (or the potential natural) vegetation do therefore and thereby also reveal ecological regions.

Problems in Classifying and Mapping Vegetation for Ecological Regionalization

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