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| dc.contributor.author | Ademe, Dereje | |
| dc.date.accessioned | 2024-02-21T10:12:13Z | |
| dc.date.available | 2024-02-21T10:12:13Z | |
| dc.date.issued | 2022-04 | |
| dc.identifier.uri | http://ir.bdu.edu.et/handle/123456789/15656 | |
| dc.description.abstract | Various adaptation options are available to the anticipated climate change and variability impacts on potato production systems in the study area. However, impact estimation and adaptation potential evaluation are critical tasks to identify the most viable adaptation options. This study was thus designed to (i) perform climate analysis, (ii) evaluate the performance of SUBSTOR-Potato model, (iii) evaluate impacts of climate change and management practices, and (iv) assess the adaptation role of management practices on potato production in various agroecosystems (AESs) found in the Choke Mountain Watersheds of Northwest Ethiopian highlands. A simulation study conducted for climate change and management practices impacts assessment using a crop simulation model. Two potato varieties (medium maturing and late maturing), three planting dates (March 01, April 01 and June 01) determined based on information from climate analysis and key informants, and four nitrogen rates (0 kg/ha, 40 kg/ha, 80 kg/ha, and 120 kg/ha N) were selected to evaluate their adaptation impacts on potato yield in three climate periods and two scenarios. Input data needed for the study collected from primary and secondary sources. Climate analysis performed at landscape level, whereas the model calibrated and evaluated using field measured data from three AESs. Water limited potential yield, yield gap, and climate change and management practices impact assessment performed using a validated model. Results revealed that all AES warmed significantly in all seasons over the historical analysis period (1981–2016) with higher magnitude of trend in high elevation AES. Rainfall variability was also large across AES, with largest interannual variability found in the dry season. Trends in temperature extremes are generally consistent across sites and AES, but with different implications for agricultural activities in the different AES. Future projections showed significant wetting and increase in precipitation (8–1015 mm additional rainfall) and temperature extremes (More summer days, few chill days, and higher day and night temperature) across AES. High inter-annual variability of rainfall onset (49–84 days) and cessation (41–66 days) dates was observed, and length of the growing period exhibited a significant trend (extended by 6–17 days in some areas and shortened by up to 7 days in other sites) in some AES and greater variability in higher elevation AES (78 – 102 days). Significant increasing trends and variability in dry spells and onset date may severely affect crop production that necessitate the revision of AES specific crop production calendar to minimize crop failure. The results also emphasize the importance of AES-based improved seasonal weather forecasts and tailored climate information services to guide farm decisions. It also concluded that AES level analysis could better provide actionable information for decision makers and growers than site specific and scattered studies. Model evaluation results confirmed that SUBSTOR-Potato model has strong ability to reproduce observed values and is suitable to simulate tuber yield in tropical highlands and similar agroecologies. Results of simulation studies showed that planting season temperature and rainfall had increased in the future climate periods with possible impacts on potato yield. Results further revealed that climate change in the area showed a wider range yield impact (0.25% to 281%) across periods and sites compared to the current practice (6 – 41 t/ha) and major benefit is found in high altitude AESs and in the mid-century period. Future climate change will also resulted in change in water limited potential yield that ranges from –7 t/ha (in AES3) to 40 t/ha (in AES5) in mid-century climate period under RCP8.5. Adaptation option assessment results showed that switching to late maturing variety (-15.4%–180.3%), delayed (June 01) planting time (4.7 – 21.8%) and high nitrogen (120 kg/ha) rate (9.55–28.8%) gave better results. Adaptation role assessment showed that late and mid-planting of late variety with higher nitrogen rates had positive impacts under the current climate and strong adaptation impact in the near-term period. In the mid-century climate period, mid-planting of both varieties with higher nitrogen rates had impact in the current climate with adaptation role in the future climate. Thus, moving the planting time to mid-planting time would have strong adaptation role and minimize GHG emissions, thereby balances trade-off between productivity and mitigation activities. | en_US |
| dc.language.iso | en_US | en_US |
| dc.publisher | Bahir Dar, Ethiopia | en_US |
| dc.subject | Agronomy | en_US |
| dc.title | Impacts of Climate Change and Management Practices on Potato (Solanum Tuberosum L.) Production in Tropical Highland Regions of Ethiopia | en_US |
| dc.type | Dissartation | en_US |
