Soil Gamasina from savanna and ReviTec site of Ngaoundéré (Adamawa, Cameroon): abundance and species diversity


  • Dieudonné Djackba Danra University of Ngaoundéré, Faculty of Science, Department of Biological Sciences, P.O. Box 454, Ngaoundéré, Cameroon
  • Elias Nchiwan Nukenine University of Ngaoundéré, Faculty of Science, Department of Biological Sciences, P.O. Box 454, Ngaoundéré, Cameroon
  • Hartmut Koehler University of Bremen, UFT Center for Environmental Research and Sustainable Technology, 28359 Bremen, Germany



ReviTec, Gamasina, Cameroon, savanna, high Guinean savanna ecozone


Soil Gamasina of Central African savanna are little known. In our study, Gamasina were assessed for a high Guinean savanna and for selected treatments of a ReviTec site for the rehabilitation of degraded soil, Ngaoundéré region (Adamawa, Cameroon). The experimental site was established in 2012. Four years later, in 2016, four sampling campaigns during the rainy season were undertaken (May, June, July, August). The investigated treatments were: (1) compost + mycorrhiza (cpmy), (2) compost + biochar (cpbc), (3) compost + biochar + bokashi (cpbcbo). The controls were: ReviTec control (ctrl1) and adjacent savanna (sav). Gamasina were extracted from 0 – 10 cm soil using a modified Berlese-Tullgren extractor and identified microscopically at the morphospecies level. Most of the thirty-four species belonging to fourteen genera and eight families seem to be new to science; they are treated as morphospecies with preliminary names.  In comparison to savanna and control, the investigated ReviTec treatments increased total Gamasina abundance up to factor five and species number by factor two. Gamasina clearly preferred compost + biochar (cpbc) and compost + biochar + bokashi (cpbcbo) treatments compared to compost + mycorrhiza (cpmy). This confirmed our previous investigations in the same experiment. Expectations for low abundances and diversity of Gamasina in the savanna subjected to a four months’ dry season have to be rejected. Expectations that the ReviTec application is initiating and accelerating the successional process are confirmed.



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How to Cite

Danra, D. D. ., Nukenine, E. N. ., & Koehler, H. . (2018). Soil Gamasina from savanna and ReviTec site of Ngaoundéré (Adamawa, Cameroon): abundance and species diversity. SOIL ORGANISMS, 90(3), 187–198.