Summary
A method of accurately estimating and mapping patterns of incoming solar radiation fluxes on sloping terrain, using data from standard meteorological instruments, is described. The results of the radiation maps produced are then related to a specific example of vegetation successional changes in the Cathedral Peak area of the Natal Drakensberg mountain range, indicating that these changes occur most readily on cooler aspects. For the same region, the differences in the major plant communities at two other sites, attributable largely to variations in incoming solar radiation loads, are discussed.
Résumé
Une méthode d'estimation fiable et d'échantillons cartographiques d'entrée de flux de radiation solaire sur des terrains en pente, utilisant des données à partir d'instruments météorologiques standard, est décrite. Les résultats des cartes de radiation obtenus sont ensuite reliés à un exemple spécifique de changements de végétation successifs dans la région de Cathedral Peak, de la Chaîne de montagnes Natal Drakensberg, indiquant que ces changements apparaissent beaucoup plus sur des pentes aux directions plus fraîches. Pour la même région, les différences dans les groupements végétaux principaux à deux autres sites, que l'on peut largement attribuer aux variations des charges de radiation solaire, sont discutées.
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Nomenclature follows the present concepts of the National Herbarium. Pretoria.
The authors wish to thank the Department of Forestry of the Republic of South Africa for providing data and for facilitating fieldwork to be undertaken at Cathedral Peak. This Research was funded in part by the South African Council for Scientific and Industrial Research, whose support is hereby gratefully acknowledged (by R.E.S.). The maps illustrating this paper were prepared by Mrs. C. Coetzee and Mr B. Martin of the University of Natal, Pietermaritzburg.
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Granger, J.E., Schulze, R.E. Incoming solar radiation patterns and vegetation response: Examples from the natal drakensberg. Plant Ecol 35, 47–54 (1977). https://doi.org/10.1007/BF02097134
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DOI: https://doi.org/10.1007/BF02097134