8007013b-8ef4-4277-9c8d-115bc9e17f27 Isaac Danso danso60@yahoo.com 2017-07-28T12:26:12 ISO 19115:2003/19139 1.0 Soil and water conservation technologies in the sudan savana of west Africa: cropping system options to increase and stabilize yields under current climate change impact. Dissertation by Isaac Danso, 2015 2015-11-13 In the Sudan Savanna region of West Africa, smallholder agricultural production is almost entirely rain-fed. Some of the major constraints to crop production are low soil fertility and high intra- and inter-annual rainfall variability. The above constraints motivated us to investigate the impact of climate change and different soil and water conservation techniques, for both high and low intensity nitrogen fertilization on yield and yield stability of key crops namely, maize, cotton and sorghum in the Sudan Savanna of Ghana (Vea), Benin (Dassari) and Burkina Faso (Dano). In the empirical studies, we evaluated the effect of tillage practices (contour and reduced tillage), nitrogen fertilizer rates (no nitrogen-N0, recommended nitrogen-NREC and high nitrogen-N2REC) and residue management (improved and standard) on the yield of maize, sorghum and cotton, for two landscape positions (upslope and footslope) in an on-farm researcher managed experiment. The 3 locations each with 3 growing seasons (2012, 2013 and 2014) were analyzed as 9 contrasting or site-seasons. Over all site-seasons, crops planted at the footslope had 31% higher relative yields and 18% higher relative aboveground biomass than those planted at the upslope. Generally, the use of contour ridging in combination with improved residue management and recommended N fertilizer was justified regardless of site-seasons and landscape position. The experimental data from short season maize (Dorke SR) was used to parameterize and evaluate the cropping system model, Decision System for Agro technology Transfer (DSSAT V 4.6) CERES-Maize. The simulated effects of climate change and adaptation options to reduce negative effect of climate change on maize were assessed. Daily climatic data for the period 2040-2060 under the scenarios RCP 4.5 and 8.5 were obtained from Regional Climate Model version 4 (RegCM4). Both scenarios show an increase in mean temperature of 0.7, 1.5 and 1.7oC for Dano, Vea and Dassari respectively as compared to baseline 1985-2004. Precipitation is projected to increase by 40, 44 and 47% in Dano, Vea and Dassari respectively by 2050 under the two scenarios. Assessment of climate impacts on maize grain yield suggest a reduction in yield of 72, 42 and 41% for Dano , Vea and Dassari for no N fertilizer and a reduction in yield of 53, 37 and 11% for Dano, Vea and Dassari respectively under recommended N fertilizer. Analysis of adaptation measures (recommended nitrogen fertilizer, contour ridges and improved residues management as adaptation No 1 (NREC) and high nitrogen, contour ridges and improved residue management as adaptation No 2 (N2REC) with both adaptations tested under single and split dose of nitrogen application) indicated substantial reduction of negative impacts of climate change on maize grain yield as compared to the current practice by farmers (without adaptation). N2REC and NREC were able to reduce the negative impact of climate change on current maize production in the Sudan Savanna by 75 and 45% respectively. On the two methods of N fertilizer application, model estimated 64% for split and 56% for single nitrogen fertilizer application in reducing negative impact of climate change across the three sites relative to the current farmers’ practices. The biggest benefit of reducing the effect of climate change on maize in this study will be the replacement of short season Dorke SR with long duration high temperature tolerant maize cultivar with high thermal requirements. This cultivar will develop under more favorable thermal and rainfall conditions, increasing the duration of vegetative phase, which intend will lead to increased yield. Policy makers should therefore create the enabling environment for farmers to afford credits to change crop and agronomic strategies in response to negative impact of climate change. Additionally improving the knowledge and skills of the few extension agents in the Sudan Savanna region on climate change and adaptation strategies is crucial in successful adaptation program to combat climate change. Isaac Danso Institute of Crop Science and Resource Conservation Division Soil Science, University of Bonn PhD student Katzenburgweg 5 Bonn 53115 Germany danso60@yahoo.com https://wascal-dataportal.org/geonetwork/srv/eng/resources.get?uuid=8007013b-8ef4-4277-9c8d-115bc9e17f27&fname=Diss.png large_thumbnail png conservation GEMET - Concepts, version 2.4 2010-01-13 geonetwork.thesaurus.external.theme.gemet sudan savanna soil conservation climate variability climate change Western Africa Ghana Burkina Faso Benin Region 2006-09-22 geonetwork.thesaurus.external.place.regions Citation: Danso, I. (2015): Soil and water conservation technologies in the West African Sudan Savanna: Cropping system options to address variability of crop yield and impacts of climate change. urn:nbn:de:hbz:5n-42214 97ab3a74-a9fd-4ecc-acfe-f992268fe5fc 2bca2f79-f650-4923-a408-415f621315bb 60f8fcf5-dcc7-4214-92f1-d16b1e7bfa8f ca409f87-8d7f-40d7-a6f2-9ad707319157 f1b23b66-b5a0-47cc-a496-9a4f849019b5 490cb699-9e7e-4d84-abb7-3819530c5b2c 50a23804-6713-495a-b773-2999b1b70f12 90972c8c-2f5e-4f01-9dd2-866df6b65c31 7d3767b2-f804-4a33-aeee-94273de52d20 d263b2a7-d77e-4a72-a9e4-6dc17d575ede 9a92bc92-9088-4661-80b9-956fa124f6ea caa6c21c-5bbb-4741-b7e2-c120aa4ea3ee 76e63367-e3ed-4375-9024-459cd276d030 9a82df62-0f50-4bc2-9c0a-5ca0a1fa4550 5eba377a-f190-4141-b4aa-6fafc3b013b5 0fbb1fa1-83ac-453e-96fd-334081eb06aa farming -3.164019739751743 1.7578552595631716 9.89379628159343 12.308494238535555 PhD thesis Universitäts- und Landesbibliothek Bonn https://wascal-dataportal.org/geonetwork/srv/eng/file.disclaimer?uuid=8007013b-8ef4-4277-9c8d-115bc9e17f27&fname=Isaac_DANSO_Thesis_printed.pdf&access=private WWW:DOWNLOAD-1.0-http--download Isaac_DANSO_Thesis_printed.pdf File to download http://hss.ulb.uni-bonn.de/2015/4221/4221.htm WWW:LINK-1.0-http--link Download of Dissertation from Uni Bonn library