Dendrochronology in the dry tropics: the Ethiopian case

T. Wils, U. Sass-Klaassen, Z. Eshetu, A. Bräuning, A. Gebrenirstos, C. Couralet, I. Robertson, R. Touchan, M. Koprowski, D. Conway, K.R. Briffa, H. Beeckman

Research output: Contribution to journalArticleAcademicpeer-review

44 Citations (Scopus)


Dendrochronology is developing outside temperate and boreal regions. Over the past decade substantial progress has been made in Mediterranean and wet tropical regions. However, research in dry tropical regions, notably those of sub-Saharan Africa, has remained fragmentary. Here, we try to identify the unique challenges and opportunities of dendrochronology in the dry tropics. First, we briefly review the status of dendrochronology outside temperate and boreal regions with an emphasis on sub- Saharan Africa. Subsequently, we focus upon one of those areas where dendrochronology in the dry tropics is at the forefront of scientific advance: Ethiopia. A detailed review of tree ring studies in the lowlands and highlands highlights the complexity of ring formation and made us identify four major types of growth ring expression: anatomically notdistinct rings, multiple rings per year, annual rings and multiple missing rings. This complex tree growth behaviour is associated with large-scale variations in precipitation regime (unimodal to multimodal) and relatively small-scale variations in tree sensitivity to water availability. Literature results are used to develop a scheme that can be used to predict differences in growth ring formation along gradients in these two factors. Because of the exceptional growth sensitivity of and the importance of local site conditions (topography, biological factors, etc.) for most trees sampled, those growing at the limits of their ecological amplitude are prone to possess multiple rings per year or multiple missing rings. In such circumstances, site selection should not always take place at the limits of the ecological amplitude of a species, but may sometimes have to be diverted to more mesic environments. Successful studies are now appearing, such as those reporting correlations between tree ring chronologies and Blue Nile river flows.
Original languageEnglish
Pages (from-to)345-354
JournalTrees-Structure and Function
Issue number3
Publication statusPublished - 2011


  • climate-growth relationships
  • tree-ring analysis
  • pterocarpus-angolensis
  • rhizophora-mucronata
  • isotope ratios
  • stable carbon
  • africa
  • forests
  • dynamics
  • reconstruction

Fingerprint Dive into the research topics of 'Dendrochronology in the dry tropics: the Ethiopian case'. Together they form a unique fingerprint.

Cite this