Savannah Phenological Dynamics Reveal Spatio-Temporal Landscape Heterogeneity in Karamoja Sub-region, Uganda
Phenological properties are critical in understanding global environmental change patterns. This study analyzed phenological dynamics in a savannah dominated semi-arid environment of Uganda. We used moderate-resolution imaging spectroradiometer normalized difference vegetation index (MODIS NDVI) ima...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2020-12-01
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| Series: | Frontiers in Sustainable Food Systems |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fsufs.2020.541170/full |
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| author | Anthony Egeru Anthony Egeru John Paul Magaya Derick Ansyijar Kuule Aggrey Siya Anthony Gidudu Bernard Barasa Jjumba Justine Namaalwa |
| author_facet | Anthony Egeru Anthony Egeru John Paul Magaya Derick Ansyijar Kuule Aggrey Siya Anthony Gidudu Bernard Barasa Jjumba Justine Namaalwa |
| author_sort | Anthony Egeru |
| collection | DOAJ |
| description | Phenological properties are critical in understanding global environmental change patterns. This study analyzed phenological dynamics in a savannah dominated semi-arid environment of Uganda. We used moderate-resolution imaging spectroradiometer normalized difference vegetation index (MODIS NDVI) imagery. TIMESAT program was used to analyse the imagery to determine key phenological metrics; onset of greenness (OGT), onset of greenness value, end of greenness time (EGT), end of greenness value, maximum NDVI, time of maximum NDVI, duration of greenup (DOG) and range of normalized difference vegetation index (RNDVI). Results showed that thicket and shrubs had the earliest OGT on day 85 ± 14, EGT on day 244 ± 32 and a DOG of 158 ± 25 days. Woodland had the highest NDVI value for maximum NDVI, OGT, EGT, and RNDVI. In the bushland, OGT occurs on average around day 90 ± 11, EGT on day 255 ± 33 with a DOG of 163 ± 36 days. The grassland showed that OGT occurs on day 96 ± 13, EGT on day 252 ± 36 with a total DOG of 156 ± 33 days. Early photosynthesis activity was observed in central to eastern Karamoja in the districts of Moroto and Kotido. There was a positive relationship between rainfall and NDVI across all vegetation cover types as well as between phenological parameters and season dynamics. Vegetation senescence in the sub-region occurs around August to mid-September (day 244–253). The varied phenophases observed in the sub-region reveal an inherent landscape heterogeneity that is beneficial to extensive pastoral livestock production. Continuous monitoring of savannah phenological patterns in the sub-region is required to decipher landscape ecosystem processes and functioning. |
| first_indexed | 2024-12-19T14:44:48Z |
| format | Article |
| id | doaj.art-121a29dd5a7544c4a75cc21a8510e3c9 |
| institution | Directory Open Access Journal |
| issn | 2571-581X |
| language | English |
| last_indexed | 2024-12-19T14:44:48Z |
| publishDate | 2020-12-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Sustainable Food Systems |
| spelling | doaj.art-121a29dd5a7544c4a75cc21a8510e3c92022-12-21T20:16:59ZengFrontiers Media S.A.Frontiers in Sustainable Food Systems2571-581X2020-12-01410.3389/fsufs.2020.541170541170Savannah Phenological Dynamics Reveal Spatio-Temporal Landscape Heterogeneity in Karamoja Sub-region, UgandaAnthony Egeru0Anthony Egeru1John Paul Magaya2Derick Ansyijar Kuule3Aggrey Siya4Anthony Gidudu5Bernard Barasa6Jjumba Justine Namaalwa7Department of Environmental Management, Makerere University, Kampala, UgandaRegional Universities Forum for Capacity Building in Agriculture (RUFORUM), Kampala, UgandaDepartment of Geomatics and Land Management, College of Engineering, Design, Art and Technology, Makerere University, Kampala, UgandaDepartment of Environmental Management, Makerere University, Kampala, UgandaDepartment of Biosecurity, Ecosystems and Veterinary Public Health, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, UgandaDepartment of Geomatics and Land Management, College of Engineering, Design, Art and Technology, Makerere University, Kampala, UgandaDepartment of Geography and Social Studies, Kyambogo University, Kampala, UgandaDepartment of Environmental Management, Makerere University, Kampala, UgandaPhenological properties are critical in understanding global environmental change patterns. This study analyzed phenological dynamics in a savannah dominated semi-arid environment of Uganda. We used moderate-resolution imaging spectroradiometer normalized difference vegetation index (MODIS NDVI) imagery. TIMESAT program was used to analyse the imagery to determine key phenological metrics; onset of greenness (OGT), onset of greenness value, end of greenness time (EGT), end of greenness value, maximum NDVI, time of maximum NDVI, duration of greenup (DOG) and range of normalized difference vegetation index (RNDVI). Results showed that thicket and shrubs had the earliest OGT on day 85 ± 14, EGT on day 244 ± 32 and a DOG of 158 ± 25 days. Woodland had the highest NDVI value for maximum NDVI, OGT, EGT, and RNDVI. In the bushland, OGT occurs on average around day 90 ± 11, EGT on day 255 ± 33 with a DOG of 163 ± 36 days. The grassland showed that OGT occurs on day 96 ± 13, EGT on day 252 ± 36 with a total DOG of 156 ± 33 days. Early photosynthesis activity was observed in central to eastern Karamoja in the districts of Moroto and Kotido. There was a positive relationship between rainfall and NDVI across all vegetation cover types as well as between phenological parameters and season dynamics. Vegetation senescence in the sub-region occurs around August to mid-September (day 244–253). The varied phenophases observed in the sub-region reveal an inherent landscape heterogeneity that is beneficial to extensive pastoral livestock production. Continuous monitoring of savannah phenological patterns in the sub-region is required to decipher landscape ecosystem processes and functioning.https://www.frontiersin.org/articles/10.3389/fsufs.2020.541170/fullconflictdrylandsgrazingmobilitypastoral |
| spellingShingle | Anthony Egeru Anthony Egeru John Paul Magaya Derick Ansyijar Kuule Aggrey Siya Anthony Gidudu Bernard Barasa Jjumba Justine Namaalwa Savannah Phenological Dynamics Reveal Spatio-Temporal Landscape Heterogeneity in Karamoja Sub-region, Uganda Frontiers in Sustainable Food Systems conflict drylands grazing mobility pastoral |
| title | Savannah Phenological Dynamics Reveal Spatio-Temporal Landscape Heterogeneity in Karamoja Sub-region, Uganda |
| title_full | Savannah Phenological Dynamics Reveal Spatio-Temporal Landscape Heterogeneity in Karamoja Sub-region, Uganda |
| title_fullStr | Savannah Phenological Dynamics Reveal Spatio-Temporal Landscape Heterogeneity in Karamoja Sub-region, Uganda |
| title_full_unstemmed | Savannah Phenological Dynamics Reveal Spatio-Temporal Landscape Heterogeneity in Karamoja Sub-region, Uganda |
| title_short | Savannah Phenological Dynamics Reveal Spatio-Temporal Landscape Heterogeneity in Karamoja Sub-region, Uganda |
| title_sort | savannah phenological dynamics reveal spatio temporal landscape heterogeneity in karamoja sub region uganda |
| topic | conflict drylands grazing mobility pastoral |
| url | https://www.frontiersin.org/articles/10.3389/fsufs.2020.541170/full |
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