Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation
Tropical Africa is affected by intense land-use change, particularly forest conversion to agricultural land. In this study, the stream discharge of four small headwater catchments located within an area of 6 km2 in western Kenya was examined for 2 years (2007 and 2008). The four catchments cover a d...
| Autores principales: | , , , , , |
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| Formato: | Journal Article |
| Lenguaje: | Inglés |
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American Meteorological Society
2012
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| Materias: | |
| Acceso en línea: | https://hdl.handle.net/10568/94316 |
| _version_ | 1855522393244565504 |
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| author | Recha, John W.M. Lehmann, Johannes Walter, M.T. Pell, A. Verchot, Louis V. Johnson, M. |
| author_browse | Johnson, M. Lehmann, Johannes Pell, A. Recha, John W.M. Verchot, Louis V. Walter, M.T. |
| author_facet | Recha, John W.M. Lehmann, Johannes Walter, M.T. Pell, A. Verchot, Louis V. Johnson, M. |
| author_sort | Recha, John W.M. |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | Tropical Africa is affected by intense land-use change, particularly forest conversion to agricultural land. In this study, the stream discharge of four small headwater catchments located within an area of 6 km2 in western Kenya was examined for 2 years (2007 and 2008). The four catchments cover a degradation gradient ranging from intact forest to agricultural land under maize cultivation for 5, 10, and 50 years. The runoff ratio (e.g., annual catchment discharge expressed as a percentage of rainfall) increased with increasing duration of cultivation from an average of 16.0% in the forest to 32.4% in the 50-yr-old agricultural catchment. Similarly, the average runoff ratio due to the stormflow component was 0.033 in the forest and increased gradually to 0.095 with increasing duration of cultivation. The conversion from forest to agricultural land in the first 5 years caused about half of the total observed increases in runoff ratio (46.3%) and discharge in relation to rainfall (50.6%). The other half of the changes in discharge occurred later during soil degradation after forest clearing. With increasing duration of cultivation, soil bulk density ρb at a depth of 0–0.1 m increased by 46%, while soil organic carbon (SOC) concentrations and total porosity decreased by 75% and 20%, respectively. The changes in hydrological responses that occurred in the initial years after forest clearing may suggest a significant potential for improved land management in alleviating runoff and enhanced storm flow and moisture retention in agricultural watersheds. |
| format | Journal Article |
| id | CGSpace94316 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 2012 |
| publishDateRange | 2012 |
| publishDateSort | 2012 |
| publisher | American Meteorological Society |
| publisherStr | American Meteorological Society |
| record_format | dspace |
| spelling | CGSpace943162025-06-17T08:23:35Z Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation Recha, John W.M. Lehmann, Johannes Walter, M.T. Pell, A. Verchot, Louis V. Johnson, M. carbon agriculture catchment hydrology deforestation composition cultivation degradation fertilizers continuous cropping cycling aquatic environment eutrophication Tropical Africa is affected by intense land-use change, particularly forest conversion to agricultural land. In this study, the stream discharge of four small headwater catchments located within an area of 6 km2 in western Kenya was examined for 2 years (2007 and 2008). The four catchments cover a degradation gradient ranging from intact forest to agricultural land under maize cultivation for 5, 10, and 50 years. The runoff ratio (e.g., annual catchment discharge expressed as a percentage of rainfall) increased with increasing duration of cultivation from an average of 16.0% in the forest to 32.4% in the 50-yr-old agricultural catchment. Similarly, the average runoff ratio due to the stormflow component was 0.033 in the forest and increased gradually to 0.095 with increasing duration of cultivation. The conversion from forest to agricultural land in the first 5 years caused about half of the total observed increases in runoff ratio (46.3%) and discharge in relation to rainfall (50.6%). The other half of the changes in discharge occurred later during soil degradation after forest clearing. With increasing duration of cultivation, soil bulk density ρb at a depth of 0–0.1 m increased by 46%, while soil organic carbon (SOC) concentrations and total porosity decreased by 75% and 20%, respectively. The changes in hydrological responses that occurred in the initial years after forest clearing may suggest a significant potential for improved land management in alleviating runoff and enhanced storm flow and moisture retention in agricultural watersheds. 2012-12-01 2018-07-03T10:57:20Z 2018-07-03T10:57:20Z Journal Article https://hdl.handle.net/10568/94316 en Open Access American Meteorological Society Recha, J.W., Lehmann, J., Walter, M.T., Pell, A., Verchot, L.V., Johnson, M. . 2012. Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation Earth Interactions, 16 (13) : 1-18. https://doi.org/10.1175/2012EI000439.1 |
| spellingShingle | carbon agriculture catchment hydrology deforestation composition cultivation degradation fertilizers continuous cropping cycling aquatic environment eutrophication Recha, John W.M. Lehmann, Johannes Walter, M.T. Pell, A. Verchot, Louis V. Johnson, M. Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation |
| title | Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation |
| title_full | Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation |
| title_fullStr | Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation |
| title_full_unstemmed | Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation |
| title_short | Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation |
| title_sort | stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation |
| topic | carbon agriculture catchment hydrology deforestation composition cultivation degradation fertilizers continuous cropping cycling aquatic environment eutrophication |
| url | https://hdl.handle.net/10568/94316 |
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