Browsing by Author "Msongaleli, Barnabas M."

Now showing 1 - 3 of 3
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    Impacts of climate variability and change on rainfed sorghum and maize: implications for food security policy in Tanzania
    (Canadian Center of Science and Education, 2015) Msongaleli, Barnabas M.; Rwehumbiza, Filbert; Tumbo, Siza D.; Kihupi, Nganga
    Concern about food security has increased because of a changing climate, which poses a great threat to food crop productivity. Climate change projections from the Coupled Model Inter-comparison Project phase 5 (CMIP5) and crop models were used to investigate the impacts of climate change on rain-fed cereal production. Calibrated and evaluated crop models simulated maize and sorghum yields over time periods and scenarios across central zone Tanzania with and without adaptation. Simulation outputs without adaptation showed predominant decrease and increase in maize and sorghum yields, respectively. The results showed that maize yields were predicted to decline between 1% and 25% across periods, representative concentration pathways (RCPs) and global circulation models (GCMs). However, sorghum yields were on average predicted to increase between 5% and 21%. Overall when adaptation is incorporated toward mid-century, yields are projected to increase for both crops. The yield projections variation between cereal crops highlights the importance of location and crop specific climate change impact assessments. Despite the uncertainties in predicting the impacts of climate change on rainfed crops, especially on cereals (maize and sorghum) which are important staple food crops in semi-arid Tanzania, the findings of this study enable policy makers to develop plans aimed at sustainable food security. In conclusion, the results demonstrate the presumption that sorghum productivity stands a better chance than maize under prospects of negative impacts from climate change in central zone Tanzania.
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    Integrated assessment of climate change impacts and adaptation in agriculture: The case study of the Wami river sub-basin, Tanzania
    (Springer International Publishing, 2020) Tumbo, Siza D; Mutabazi, Khamaldin D.; Mourice, Sixbert K.; Msongaleli, Barnabas M.; Wambura, Frank J.; Mzirai, Omari B.; Kadigi, Ibrahim L.; Kahimba, Frederick C.; Mlonganile, Peter; Ngongolo, Hashim K.; Sangalugembe, Chuki; Rao, Karuturi P. C.; Valdivia, Roberto O.
    This study evaluates the impacts of climate change and an adaptation strategy on agriculture in the Wami River sub-basin in Tanzania. This study uses the Agricultural Model Improvement and Inter-comparison Project (AgMIP) framework that integrates climate, crops and economic models and data using a novel multi-model approach for impact assessment of agricultural systems under current and future conditions. This study uses five Global Circulation Models (GCMs) from the fifth phase of the Coupled Model Inter-comparison Project (CMIP5), two crop simulation models, and one economic impact assessment model. In this study, a representative agricultural pathways (RAP) that characterises future conditions following ‘business-as-usual’ trends was developed and used to model future agricultural systems in the Wami River sub-basin. Results show that by mid-century, the maximum and minimum temperatures will increase by 1.8–4.1 °C and 1.4–4.6 °C, respectively. Rainfall is predicted to be variable with some places projected to increase by 12%, while in other areas it is projected to decrease by 14–28%. Maize yields under these conditions are projected to decrease by 5.3–40.7%. Results show that under current conditions, 50–60% of farm households are vulnerable to losses due to climate change. The impacts of climate change on poverty and per capita income are also projected to be negative. Under the current production system, poverty rates were projected to increase by 0.8–15.3% and per-capita income to drop by 1.3–7.5%. Future socio-economic conditions and prices offset the negative impacts of climate change. Under future conditions, the proportion of households vulnerable to loss is estimated to range from 25 to 50%. Per-capita income and poverty rates are expected to improve under the future climate change conditions. Poverty rates would decrease between 1.9 and 11.2% and income per-capita would increase between 2.6 and 18.5%. The proposed future adaptation package will further improve household livelihoods. This integrated assessment of climate change projections using the improved methods and tools developed by AgMIP has contributed to a better understanding of climate change and adaptation impacts in a holistic manner.
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    Performance of sorghum varieties under variable rainfall in Central Tanzania
    (Hindawi, 2017) Msongaleli, Barnabas M.; Tumbo, S. D.; Kihupi, N. I.; Rwehumbiza, Filbert B.
    Rainfall variability has a significant impact on crop production with manifestations in frequent crop failure in semiarid areas. This study used the parameterized APSIM crop model to investigate how rainfall variability may affect yields of improved sorghum varieties based on long-term historical rainfall and projected climate. Analyses of historical rainfall indicate a mix of non-significant and significant trends on the onset, cessation, and length of the growing season. The study confirmed that rainfall variability indeed affects yields of improved sorghum varieties. Further analyses of simulated sorghum yields based on seasonal rainfall distribution indicate the concurrence of lower grain yields with the 10-day dry spells during the cropping season. Simulation results for future sorghum response, however, show that impacts of rainfall variability on sorghum will be overridden by temperature increase. We conclude that, in the event where harms imposed by moisture stress in the study area are not abated, even improved sorghum varieties are likely to perform poorly.