Intermediate evergreen Afromontane forest (IAF) in northwestern Ethiopia: observations, description and modelling its potential distribution

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

  • Abiyot Berhanu
  • Sebsebe Demissew
  • Zerihun Woldu
  • Friis, Ib
  • Paulo Van Breugel
Research question: In the most recent vegetation map of Ethiopia, the vegetation was classified into 19 types and subtypes. Uncertainty exists, however, about the classification of some areas, including forests of the northwestern Ethiopia and particularly Awi Zone, Zege Peninsula and Islands of Lake Tana. Do these forests belong to the established vegetation types of Ethiopia or to a new vegetation type? Study area: Primary data was collected from the forests of Awi Zone and secondary data from Zege Peninsula and the Islands of Lake Tana, in northwestern Ethiopia. Potential vegetation distribution modelling was accomplished for the entire country of Ethiopia.
Methods and results: For vegetation data sampling, a total of 154 plots along 36 line transects, with total area of 6.16 ha, were investigated in Guangua-Illala and Khatasa forests in Awi. Climate and soil data were acquired from freely available online sources (WORLDCLIM and SOILGRIDS). Generally, four major steps were followed to determine if a new vegetation type is warranted: 1) floristic composition of the study area was investigated and compared with other study areas / vegetations (similarity analysis); 2) plant communities were classified and indicator species identified for each community in the study area (community analysis); 3) the indicator species were used in the potential distribution modelling and mapping (MaxEnt modelling); and 4) ground-truthing was carried out for the new vegetation type. The forests of the study area, Zege Peninsula and Islands of Lake Tana were found to be highly similar with the Dry evergreen Afromontane forest (DAF) and Moist evergreen Afromontane forest (MAF) except the absence of primary elements of the DAF and MAF in those forests. Vegetation distribution modelling showed highly similar forests are distributed in the Gojam and Gondar Floristic Regions. Those areas were also found to have an intermediate/transitional climate type between the MAF and DAF of Ethiopia. Conclusion: The results of the vegetation comparisons and distribution modelling showed the forests in Awi, Islands of Lake Tana, Zege Peninsula and the surrounding areas belong to a new vegetation type we named Intermediate evergreen Afromontane forest (IAF). The new vegetation type includes forests transferred from the DAF and some forests from the MAF.
Udgave nummer4
Sider (fra-til)351-367
StatusUdgivet - 19 okt. 2018

ID: 200734590