The ability to adequately and continually assess the hydrological catchment response to extreme rainfall events in a timely manner is a prerequisite component in flood-forecasting and mitigation initiatives. Owing to the scarcity of data, this particular subject has captured less attention in Rwanda. However, semi-distributed hydrological models have become standard tools used to investigate hydrological processes in data-scarce regions. Thus, this study aimed to develop a hydrological modeling system for the Nyabarongo River catchment in Rwanda, and assess its hydrological response to rainfall events through discharged flow and volume simulation. Initially, the terrain Digital Elevation Model (DEM) was pre-processed using a geospatial tool (HEC-GeoHMS) for catchment delineation and the generation of input physiographic parameters was applied for hydrological modeling system (HEC-HMS) setup. The model was then calibrated and validated at the outlet using sixteen events extracted from daily hydro-meteorological data (rainfall and flow) for the rainy seasons of the country. More than in other events, the 15th, 9th, 13th and 5th events showed high peak flows with simulated values of 177.7 m³s⁻¹, 171.7 m³s⁻¹, 169.9 m³s⁻¹, and 166.9 m³s⁻¹, respectively. The flow fluctuations exhibited a notable relation to rainfall variations following long and short rainy seasons. Comparing the observed and simulated hydrographs, the findings also unveiled the ability of the model to simulate the discharged flow and volume of the Nyabarongo catchment very well. The evaluated model’s performance exposed a high mean Nash Sutcliffe Efficiency (NSE) of 81.4% and 84.6%, with correlation coefficients (R²) of 88.4% and 89.8% in calibration and validation, respectively. The relative errors for the peak flow (5.5% and 7.7%) and volume (3.8% and 4.6%) were within the acceptable range for calibration and validation, respectively. Generally, HEC-HMS findings provided a satisfactory computing proficiency and necessitated fewer data inputs for hydrological simulation under changing rainfall patterns in the Nyabarongo River catchment. This study provides an understanding and deepening of the knowledge of river flow mechanisms, which can assist in establishing systems for river monitoring and early flood warning in Rwanda.

This work studied the vegetation in a seven-hectare self-regenerated and protected forest about nine decades-old located in a previously cultivated site in the Ruhande Arboretum to identify woody species and their diversity. Ten parallel transects were established at 34m intervals, leaving 25m on either side to avoid an edge effect. Along transects, circular 16m diameter plots spaced 20m apart were established, making a total of 56 plots. In each plot, woody species were recorded and those with heights >2m had their diameter at breast height measured. Phytosociological data including basal area, density, and frequency and their respective relative values were computed and used to determine species and family importance value indices within each plot. Across all plots, twenty-eight genera in 17 families were identified and 844 plants were recorded, including 755 trees and 89 shrubs, with most trees found in smaller diameter classes. Across all plots, only one Markhamia lutea tree was in the 5060cm diameter class and one Polyscias fulva was in the >90cm diameter class. Of all woody species, Polyscias fulva was the most dominant since it had individuals with the biggest diameter. The number of individuals per family across all plots ranged from one for Cupressaceae, Dracaenaceae, Moraceae, and Solanaceae to 414 for Bignoniaceae. Across all plots, the diameter at breast height ranged from 1.897cm. The species importance value index ranged from 0.341.8 for Nicotiana tabacum and P. fulva, respectively, while the family importance value index ranged from 0.2 for Annonaceae, Cupressaceae, Dracaenaceae, and Solanaceae to 41.6 for Araliaceae. Shannon and Simpsons diversity indices were 1.772 and 0.707, respectively, while the evenness was 0.532, signifying that the forest was reasonably diverse. It is recommended that this forest can be conserved owing to its rich vegetation and to monitor its successional development.

Extracurricular inter-professional activities advance pre-service student skills and confidence before joining the workforce. This article describes an extracurricular model, whereby students engaged in experiential learning, and had the opportunity to challenge themselves in interprofessional groups guided by faculty and inspired by professionals in their respective fields. The Global One Health Case Competition involved students from the University of Rwanda in collaboration with the University of Minnesota, and required students in teams to address an Ebola outbreak containment and response scenario. Forty students, seven faculty coaches, and five judges participated in this event. Students gained collaborative teamwork skills as they developed comprehensive strategies for managing a response to a zoonotic disease outbreak, considering political, financial, logistical, and other factors. Faculty strengthened skills in writing complex case studies for a competition model, and in mentoring of multidisciplinary student groups. Case competition is an effective educational mechanism for building the outbreak response capacity of our future workforce before they are in their real-world professional roles responding to actual zoonotic and other infectious disease threats.