Search

Background and Objective: Crustaceans play a considerable role in the ecological process of aquatic ecosystems, acting at different trophic levels as herbivores, detritivores, predators and prey and constitute an important source of animal protein for humans and livestock. This study investigated the diversity of shrimp from the left bank of the Malebo Pool in the Congo River. Study Area: Five sampling campaigns were organized from July 2020 to August 2021 in six sites (Ngamanzo 1, Ngamanzo 2, Kinkole 1, Kinkole 2, Kinsuka 1 and Kinsuka 2) in the Malebo Pool, the terminal part of the middle Congo River. Methods: Shrimp samples were collected using dip nets and creels during the experimental fisheries. Physical parameters were measured monthly in situ at six sites. Chemical parameters were assessed using an ultraviolet atomic spectrophotometer. Systematic identification of shrimp was done using appropriate systematic identification keys. The structure of the shrimp populations was studied using several ecological indices. Results: A total of 1422 shrimp specimens were sampled. These individuals belonged to three different species (Caridina africana Macrobrachium dux and Macrobrachium sollaudii), two genera (Caridina and Macrobrachium) and two families (Atyidae and Palaemonidae). Shanon and Weaver's diversity index values ranged from 0 to 1.3 indicating that the shrimp fauna is not diverse in Malebo Pool. These species are better represented at Ngamanzo 1, Ngamanzo 2 and Kinkole 2. Redundancy analysis (RDA) showed that environmental variables such as dissolved oxygen level, conductivity, water temperature, transparency, water flow velocity, plant debris, aquatic plants and canopy strongly influence taxonomic diversity across sites. Conclusion: The results obtained showed that the shrimp fauna is rich and diversified in the studied part of the Malebo Pool in the Congo River and, these organisms are essential in maintaining the ecological balance in this aquatic ecosystem.

L'étude de la physico-chimie, de la composition et de l'abondance du plancton et des macroinvertébrés du littoral du lac Tanganyika a été menée dans la zone littorale à Bujumbura (Burundi) et à Uvira (RD Congo). L'objectif de l'étude était de mettre en évidence l'impact des activités anthropiques sur la physico-chimie et le peuplement du littoral du lac Tanganyika. Pour y parvenir, des échantillons ont été collectés aux mois de février, mai, septembre et décembre 2011 dans 6 stations dont 3 (embouchure de Ruzizi, port de Bujumbura et, Nyamugari) sur la cote burundaise et 3 (Kilomoni, Maendeleo et Kalimanbenge) sur la côte congolaise. Les échantillons d'eau et de plancton ont été analysés dans le laboratoire de l'Unité d'Enseignement et de Recherche en Hydrobiologie Appliquée (UERHA) de l'ISP/Bukavu. En examinant les valeurs des différents nutriments dosés, on remarque qu'en moyenne, les valeurs sont plus élevées sur le littoral burundais que sur le littoral congolais, vraisemblablement l'effet de la ville de Bujumbura. Ainsi, la concentration des phosphates (0,11mg/l), nitrites (0,02mg/l) ammonium (57,43 μg/l) et Silice (3,72mg/l) et est plus élevée dans la station située au niveau du port de Bujumbura que dans les autres stations d'étude. La corrélation entre ces nutriments et l'abondance algale est bien mise en évidence et c'est dans la même station que la Chlorophylle a, indice de l'abondance algale, a été la plus abondante.

This research focuses on teaching medicinal plants in classrooms, as a away for bridging formal education and cultural based-conservation. Although the concept of medicinal plants is related to "Social sharp questions. This study stands on the idea that basic knowledge and pupil's representation of domesticated plants may influence the implementation of relevant school curricula in Biology, looking on society's needs and science evolution. Objectives objectives to be achieved are defined as follows: i) Inventory of domesticated medicinal plants and their therapeutic values; ii) Determine pupil's representation of medicinal plants as teaching material resources. Sampling techniques were provided by basic ethnobotanical research methods. They were tailored on mapping and selection of key informants, semi-structured interviews, and open-ended questionnaires, transect walk). The study was conducted within urban quarters (with 1259 key informants) and, in 13 schools (with 668 pupils) for getting relevant information on domestication purposes, medicinal plants uses, and teaching strategies of medicinal plants through school curriculum. Pupils (senior 4 and 5) showed personal interest and motivation for nine themes. Didactic diagrams have been developed from learner's representations; taking in account competences-based education.