An inventory of the epilithic algae has been taken during 12 months (from January up to December 2012) according to a monthly sampling per site in the 12 streams of Lwiro region: Birunga, Gaho, Kaboneke, Kabindi, Kahenu, Kanakalwiro, Kalengo, Kamirihembe, Lwiro, Mahyuza, Tchoga and Tchongoloka. The epilithic algae has been scraped from 25 cm2 of upper part of the stones. The collected sample has been put in a test tube containing 50 ml of 4% formalin. After a thorough mixture of this sample, 1ml subsample has been taken for epilithic algae identification thanks to optical microscope. The results that we got throughout this study show that these watercourses are very rich in epilithic algae with a total of 64 identified species divided into 5 classes, namely Bacillariophyceae (45.3%), Chlorophyceae (21.9%), Cyanophyceae (15.6%), Desmidiaceae (10.9%) and Euglenophyceae (6.3%). The epilithic algae of Tchongoloka is the most diversified with 20 species and that of Kabindi is the less diversified with 11 species only. The high number of individual of algae is enregitred in Tchongoloka (264 individuals) and low number in Kalengo (235 individuals). The variations of species number correspond also with the variations of density, 660 individuals/cm2 for Tchongoloka and 542.5 individuals/cm2 for Mahyuza.

This paper is a report on epibenthic algae identified in water samples recovered from Kahuzi-Biega National Park streams. The samples were collected during dry season (July-August 2007) from 10 streams. Altogether, some 170 species with 9,872 individuals have been identified, belonging to 6 algal groups containing 61 genera. Bacillariophyceae with 3,550 individuals (61 species, 20 genera) formed the most abundant group followed by Cyanophyceae with 2,551 individuals (47 species, 12 genera) and Chlorophyceae with 1,685 individuals (30 species, 15 genera). This algal community is very diversified and balanced (Shannon-Weiner index varied between 4.44-4.67, Species Diversity between 15.81-13.31 and Equitability between 0.97-0.99). The higher number of species (114 species, 55 genera) was recorded at station MV and the lesser number (91 species, 51 genera) at station MG.