Bush encroachment refers to the invasion of woody species in Savannah ecosystems driven by either anthropogenic and/or natural factors. This study sought to examine land cover changes and topographic features attributable to patterns of encroachment in Ol Pejeta Conservancy (OPC) where, Euclea divinorum unpalatable woody species has colonised former grasslands and other habitats which provide grazing grounds for herbivore wildlife species. Here, we monitored vegetation cover trends in the period 1987-2016 using five vegetation classes on Landsat images acquired during the dry season. Additionally, slope based NDVI maps and digital elevation models were used to identify topographic influences on vegetation change. Results revealed that E. divinorum increased significantly between 1987 and 2016 (Mann Kendall test for trend analysis tau 1, n=6, p< 0.01). On the other hand, Acacia drepanolobium and Acacia xanthophloea decreased from 49.72% and 5.31% in 1987 to 17.00% and 0.29% in 2016 respectively. Further, areas in low elevation were more colonised by E. divinorum. The colonising E. divinorum is unpalatable hence lacks natural predators whilst, A. drepanolobium and A. Xanthophloea which are alternative herbivory species decreased. Understanding dynamics of woody vegetation in savannah is crucial for management of healthy and sustainable ecosystems.
| Published in | International Journal of Natural Resource Ecology and Management (Volume 2, Issue 5) |
| DOI | 10.11648/j.ijnrem.20170205.11 |
| Page(s) | 85-93 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2017. Published by Science Publishing Group |
Bush Encroachment, Savannah Grassland, Land Cover Change
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APA Style
Cyrus Mutunga Kavwele, Mwangi James Kinyanjui, Johnstone Kithiki Kimanzi. (2017). Time Series Monitoring of Bush Encroachment by Euclea divinorum in Ol Pejeta Conservancy Laikipia, Kenya. International Journal of Natural Resource Ecology and Management, 2(5), 85-93. https://doi.org/10.11648/j.ijnrem.20170205.11
ACS Style
Cyrus Mutunga Kavwele; Mwangi James Kinyanjui; Johnstone Kithiki Kimanzi. Time Series Monitoring of Bush Encroachment by Euclea divinorum in Ol Pejeta Conservancy Laikipia, Kenya. Int. J. Nat. Resour. Ecol. Manag. 2017, 2(5), 85-93. doi: 10.11648/j.ijnrem.20170205.11
AMA Style
Cyrus Mutunga Kavwele, Mwangi James Kinyanjui, Johnstone Kithiki Kimanzi. Time Series Monitoring of Bush Encroachment by Euclea divinorum in Ol Pejeta Conservancy Laikipia, Kenya. Int J Nat Resour Ecol Manag. 2017;2(5):85-93. doi: 10.11648/j.ijnrem.20170205.11
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Download@article{10.11648/j.ijnrem.20170205.11,
author = {Cyrus Mutunga Kavwele and Mwangi James Kinyanjui and Johnstone Kithiki Kimanzi},
title = {Time Series Monitoring of Bush Encroachment by Euclea divinorum in Ol Pejeta Conservancy Laikipia, Kenya},
journal = {International Journal of Natural Resource Ecology and Management},
volume = {2},
number = {5},
pages = {85-93},
doi = {10.11648/j.ijnrem.20170205.11},
url = {https://doi.org/10.11648/j.ijnrem.20170205.11},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijnrem.20170205.11},
abstract = {Bush encroachment refers to the invasion of woody species in Savannah ecosystems driven by either anthropogenic and/or natural factors. This study sought to examine land cover changes and topographic features attributable to patterns of encroachment in Ol Pejeta Conservancy (OPC) where, Euclea divinorum unpalatable woody species has colonised former grasslands and other habitats which provide grazing grounds for herbivore wildlife species. Here, we monitored vegetation cover trends in the period 1987-2016 using five vegetation classes on Landsat images acquired during the dry season. Additionally, slope based NDVI maps and digital elevation models were used to identify topographic influences on vegetation change. Results revealed that E. divinorum increased significantly between 1987 and 2016 (Mann Kendall test for trend analysis tau 1, n=6, p< 0.01). On the other hand, Acacia drepanolobium and Acacia xanthophloea decreased from 49.72% and 5.31% in 1987 to 17.00% and 0.29% in 2016 respectively. Further, areas in low elevation were more colonised by E. divinorum. The colonising E. divinorum is unpalatable hence lacks natural predators whilst, A. drepanolobium and A. Xanthophloea which are alternative herbivory species decreased. Understanding dynamics of woody vegetation in savannah is crucial for management of healthy and sustainable ecosystems.},
year = {2017}
}
TY - JOUR T1 - Time Series Monitoring of Bush Encroachment by Euclea divinorum in Ol Pejeta Conservancy Laikipia, Kenya AU - Cyrus Mutunga Kavwele AU - Mwangi James Kinyanjui AU - Johnstone Kithiki Kimanzi Y1 - 2017/08/01 PY - 2017 N1 - https://doi.org/10.11648/j.ijnrem.20170205.11 DO - 10.11648/j.ijnrem.20170205.11 T2 - International Journal of Natural Resource Ecology and Management JF - International Journal of Natural Resource Ecology and Management JO - International Journal of Natural Resource Ecology and Management SP - 85 EP - 93 PB - Science Publishing Group SN - 2575-3061 UR - https://doi.org/10.11648/j.ijnrem.20170205.11 AB - Bush encroachment refers to the invasion of woody species in Savannah ecosystems driven by either anthropogenic and/or natural factors. This study sought to examine land cover changes and topographic features attributable to patterns of encroachment in Ol Pejeta Conservancy (OPC) where, Euclea divinorum unpalatable woody species has colonised former grasslands and other habitats which provide grazing grounds for herbivore wildlife species. Here, we monitored vegetation cover trends in the period 1987-2016 using five vegetation classes on Landsat images acquired during the dry season. Additionally, slope based NDVI maps and digital elevation models were used to identify topographic influences on vegetation change. Results revealed that E. divinorum increased significantly between 1987 and 2016 (Mann Kendall test for trend analysis tau 1, n=6, p< 0.01). On the other hand, Acacia drepanolobium and Acacia xanthophloea decreased from 49.72% and 5.31% in 1987 to 17.00% and 0.29% in 2016 respectively. Further, areas in low elevation were more colonised by E. divinorum. The colonising E. divinorum is unpalatable hence lacks natural predators whilst, A. drepanolobium and A. Xanthophloea which are alternative herbivory species decreased. Understanding dynamics of woody vegetation in savannah is crucial for management of healthy and sustainable ecosystems. VL - 2 IS - 5 ER -
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