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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.

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.

[Figure][1] Children play on fishing boats at Lake Tanganyika, one of the East African Great Lakes threatened by oil exploitation. PHOTO: BLICKWINKEL/ALAMY STOCK PHOTO As the world's demands for hydrocarbons increase ([ 1 ][2]), remote areas previously made inaccessible by technological

International audience; Gouvernance des Ressources Naturelles Collectives des Ecosystèmes Fragiles dans la Région des Grands Cet ouvrage traite les questions spécifiques de la gouvernance environnementale dans le contexte post-conflits de la région de Grands Lacs Africains. Les différents chapitres qui y sont développés découlent des efforts d'une recherche entreprise localement au sein des institutions d'enseignement supérieur, universitaire et de recherche. Les résultats de recherche publiés dans ce livre proviennent donc des expériences pratiques de terrain et découlent d'une démarche de recherche-action participative (à travers l'approche multi-institutionnelle) ; ceci en vue de la restauration et de la réhabilitation des ressources naturelles collectives, dans les sites à écosystèmes fragiles du Burundi et de la RD. Congo.

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.

The primary production in meromictic Lake Kivu is sustained by external nutrient inputs and by internal loading due to upwelling caused by sub-aquatic sources. We present here the results of external loading of phosphorus (P), nitrogen (N) and silica (Si) by rivers and atmospheric deposition measured from 2006 to 2008. These external inputs are compared to internal loading. The input of soluble-reactive P (SRP), supplied in equal parts from rivers and atmospheric deposition, adds up to 230 t P yr(-1), 20 times less than total P load. Ammonium (mainly via rainwater) and nitrate (mainly via rivers) are primary sources of the dissolved N load (5400 t N yr(-1)), with both species contributing similar to 50%. Dissolved Si input (40,000 t Si yr(-1)) is unique in that only similar to 60% enters by rivers, while the remaining similar to 40% comes from sub-aquatic sources and atmospheric deposition is negligible. Based oil the molar nutrient ratios, we identify P as the limiting factor for algae production. Despite the strong anthropogenic impact on the catchment and the high particle erosion (74 t km(-2) yr(-1)), the area-specific nutrient mobilization is rather low. The external nutrient input is therefore not the cause for the reported increase of methane production in the last decades. External loading to the epilimnion plays a lesser role for all three nutrients (similar to 10% for SRP, similar to 25% for dissolved N and similar to 45% for dissolved Si), as compared to the lake-internal loading by upwelling (90%, 75% and 55%, respectively). Lake Kivu, therefore, is similar to other East African large lakes in that the internal loading exceeds the external loading. Despite the substantial uncertainty of the load estimates of up to 50%, we can conclude that the observed nutrient input is consistent with the primary production of 260 g C m(-2) yr(-1) recently measured by Sarmento et al. (2006) and also consistent with the lake-internal fluxes established by Pasche et al. (in press). (C) 2009 Elsevier Inc. All rights reserved.