Diversity and ecology of wild mushrooms of Riparian zone of Lake Kivu, Rwanda

Abstract

Fungi are among the most diverse group of living organisms on earth, though inadequately studied worldwide and especially in Rwanda. The main objective of this study was to assess the diversity and describe the ecology of mushrooms species in Rwanda in order to develop a baseline that can help for further studies on fungi in the country. The Macromycetes diversity and distribution of the riparian zone of Lake Kivu were studied by plot-based mushroom surveys at 3 study sites (Mariri, Mpangara and Nyakarwa) and simple random searches in the garden of the Museum of Environment, from September 2016 to June 2017. More than 64 mushroom species were recorded, collected, dried and their specimens are conserved in the Museum of Environment of Karongi, Rwanda. A total of 64 species were collected, belonging to 8 orders, 26 families and 40 genera. It was revealed that the riparian zone of Lake Kivu is dominated by Agaricales, an order represented by 52 species, 81% of all species collected. The total order/family ratio of 0.31, family/genus ratio of 0.65 and genus/species ratio of 0.63 is an indicator of high family and generic diversity in the collections. Families highly represented in collections with the most number of species are Agaricaceae with 18 species, Tricholomataceae with 10 species and Psathyrellaceae with 5 species. In this study, Termitomyces medius was collected and recorded for the first time in Rwanda. This study has provided 14 new records on the list of mushroom species in Rwanda. Moreover, the study has also provided other 43 potential new records which were identified to genus level. More number of mushrooms species was recorded in Nyakarwa Forest and Sorenson similarity matrix calculated showed dissimilarity richness and distribution of mushrooms species among 4 sites surveyed during this study. During the study period, the number of species present increased with rainfall. The most species were recorded and collected in December and decreased to 0 in the June dry season.