Journal of Ecosystem & Ecography
Open Access

Research Article

Decline and Die-Back of Woody Plants in a Physiognomic and Floristically Complex Sebungwe Region and the Factors Modifying Mosaic Patch Landscapes at Sengwa Wildlife Area, Zimbabwe

¹Scientific Services, Zimparks, Causeway, Harare, Zimbabwe

²University of Zimbabwe, Department of Geography and Environmental Science, Geo-information and Earth Observation Centre, Mount Pleasant, Harare, Zimbabwe

*Corresponding Author:

Tafangenyasha C
Scientific Services, Zimparks
P O Box CY 140, Causeway
Harare, Zimbabwe
Tel: 07767739071/0735607804
E-mail: cliffordtafa@gmail.com

Received date May 19, 2016; Accepted date June 21, 2016; Published date June 28, 2016

Citation: Tafangenyasha C, Kavhu B, Vingi K (2016) Decline and Die-Back of Woody Plants in a Physiognomic and Floristically Complex Sebungwe Region and the Factors Modifying Mosaic Patch Landscapes at Sengwa Wildlife Area, Zimbabwe. J Ecosys Ecograph 6:194. doi:10.4172/2157-7625.1000194

Copyright: © 2016 Tafangenyasha C, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

An investigation of the status of woodlands at Sengwa Wildlife Research Area (SWRA) revealed factors influencing decline and die-back of woody plants at a time of low elephant densities. The vegetation condition of the study area in the elephant range area of the semi-arid area of northwest Zimbabwe was randomly assessed in 50 × 20 m permanently marked degraded and undegraded plots in a study area approximately 80 km2. Diversity of woody plants increased towards downstream. Percentage elephant damage was slight on undegraded plots and termite damage was three times greater on undegraded plots than degraded plots. Density of woody plants was high following a period of coppice regeneration. The results suggest regeneration of woody plants following a long period of elephant culls between 1960 and 1992 that altered forest structures. It is conceivable that other environmental agents may play the role of elephant damage in the presence of elephant densities < 1 individuals/ km2. Significant differences (p<0.05) in elephant densities (no/km2) were recorded in SWRA between 1958 and 1996, 1958 and 1993 suggesting that increasing elephant densities were negatively impacting on woody cover (%). Woody cover increased from 60% in 1993 to 70% in 1996 inside SWRA. SWRA vegetation may be on regeneration path if no adverse impacts are recorded from other environmental agents including termite activity, fungal attack (Fusarium oxysporum), Lantana camara L. invasions and drought. Epidemic die-back is not yet a common feature in the protected area. The results refute the postulation that elephant alone prevent woodland regeneration and recruitment into larger size classes by feeding on small trees. The findings suggest need to consider end to end cycle of each disturbance factor in order to accurately predict scale of vegetation change in savanna ecosystems.

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