Abstract-Propagation path loss models are useful for the prediction of received signal strength at a given distance from the transmitter; estimation of radio coverage areas of Base Transceiver Stations (BTS); frequency assignments; interference analysis; handover optimisation; and power level adjustments. Due to the differences in: environmental structures; local terrain profiles; and weather conditions, path loss prediction model for a given environment using any of the existing basic empirical models such as the Okumura-Hata's model has been shown to differ from the optimal empirical model appropriate for such an environment. In this paper, propagation parameters, such as distance between transmitting and receiving antennas, transmitting power and terrain elevation, using sea level as reference point, were used as inputs to Artificial Neural Network (ANN) for the development of an ANN based path loss model. Data were acquired in a drive test through selected rural and suburban routes in Minna and environs as dataset required for training ANN model. Multilayer perceptron (MLP) network parameters were varied during the performance evaluation process, and the weight and bias values of the best performed MLP network were extracted for the development of the ANN based path loss models for two different routes, namely rural and suburban routes. The performance of the developed ANN based path loss model was compared with some of the existing techniques and modified techniques. Using Root Mean Square Error (RMSE) obtained between the measured and the model outputs as a measure of performance, the newly developed ANN based path loss model performed better than the basic empirical path loss models considered such as: Hata; Egli; COST-231; Ericsson models and modified path loss approach.

Water stress is one of the risks emanating from worsening climatic variations. It poses serious threats on vulnerable continents, people and livelihoods globally. However, little information is available on how the specific climate threat is impacting people's livelihoods and water resources on different temporal and spatial scales in Nigeria basins. This study aimed at investigating household vulnerability and adaptation to water stress induced by climate variability on a downstream Kaduna River basin with the goal of supporting/facilitating climate change adaptation. The research analyzed hydro-climatic data and employed vulnerability-based framework consistent with stakeholders' participatory approach, within the context of current climate conditions experienced, and/or water stress conditions already affecting household livelihoods in six communities at three study sites; Shiroro, Gbako and Lavun, and adaptive strategies engaged to deal with water stress. Findings revealed that households have been exposed and experienced changes in water availability through variations in rainfall, temperature and runoff. Consequently, these changes have impacted on food production and livelihoods. Households have individually and collectively employed adaptation techniques which are reactive, short-term indigenous coping strategies usually adopted during periods of stress to minimize water-related vulnerabilities. The study demonstrated how an understanding of the local household vulnerabilities will enable the recognition of early indicators of water stress in addition to the occurrence of extreme events. Overall, households' vulnerability decreased from one village to another due to differences in sensitivity to stress, access to resources and local institutional capacity. Resilience of households can be increased through early warning system during flood

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This research work aims to study the perceptions of pastoralists and agropastoralists on climate change impacts on mobile herding and the effectiveness of herders' adaptive strategies within Kompienga Province, south-eastern region of Burkina Faso. In order to achieve this aim, survey data were retrieved from 271 respondents and analysed. From respondents' perceptions, climate change is real and is negatively affecting forage availability (in quality and quantity); livestock production and reproduction performances; herders' practices, their livelihoods and the cohabitation of herding and crop farming. To overcome the increasing constraints the pastoral herding is facing, sound and urgent actions need to be undertaken by Burkina Faso government. These actions include: 1) providing the grazing reserves with necessary facilities such as perennial reservoirs; 2) conducting research to improve breeds that would adapt to current climatic conditions; 3) encouraging and supporting gradual shift of herders from mobile herding to the sedentary breeding; 4) supporting and organizing forage production by farmers. At short term an effective cross-border framework could be created to seek for sound solutions to secure the mobility of herds within ECOWAS territory.

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