A baseline description of the soils and vegetation of Farm Klein Boesman, Khomas Region, Namibia

Authors

  • BJ Strohbach Namibia University of Science and Technology http://orcid.org/0000-0002-1542-1989
  • WF Adank Namibia University of Science and Technology
  • ME Coetzee Namibia University of Science and Technology
  • WJ Jankowitz [Deceased]. Namibia University of Science and Technology

Keywords:

Dordabis mountainveld, Kalahari Duneveld, Namibia, phytosociology, soil characterisation, soil and terrain mapping, southern Kalahari, vegetation

Abstract

The Farm Klein Boesman, south of Dordabis in the Khomas Region of Central Namibia, is situated on the ecotone between the Central Highlands/Central Plateau and the southern Kalahari. Whereas a considerable amount of information is available for the Kalahari Duneveld in South Africa, little is known of the same ecosystem in Namibia, specifically the northern extent of this ecosystem. We stratified the farm according to visible terrain features identified on aerial images, aided by a Shuttle Radar Topography Mission (SRTM) digital terrain model. Based on these initial stratification units, 35 minipits and/or soil augerings were done to sample the typical soil units. From these, soil samples were analysed for soil chemical and physical properties. In addition, 158 relevés were compiled across all initial stratification units. These were classified with modified Two-Way Indicator Species Analysis (TWINSPAN) using a synusial approach. From the results we described and mapped twelve landform and ten soil units, as well as six vegetation associations, of which two were subdivided into two and three subassociations each. We compare these associations with related vegetation types described in the Khomas Hochland as well as in the Kalahari Gemsbok National Park (KGNP) in South Africa. Although several similarities to units described for the KGNP were identified, several discrepancies were also identified, necessitating a thorough revision of the vegetation descriptions for the greater southern Kalahari.

Author Biographies

BJ Strohbach, Namibia University of Science and Technology

My interests lie in vegetation- and landscape ecology, ranging from baseline studies to applied management options. I am leading the Vegetation Survey of Namibia project, specifically aiming at providing a baseline description of the natural vegetation of Namibia. This project covers a large variety of climatic zones, landscapes and ecosystems in Namibia. Vegetation description and mapping is done at large (regional or landscape) scale, as well as at local small-scale studies on particular farm and/or conservancies. For management purposes, the vegetation is also described i.t.o. its suitability for livestock farming as well as its sensitivity to (potential) disturbance. Vegetation is not a stable feature of the landscape, but responds to anthropogenic pressure as well as climatic drivers. Changing climate has been experienced over the past years in Namibia, and future trends are uncertain. More extreme climatic conditions are predicted for the subcontinent - bigger rain storms, more heat extremes, but also more severe dry spells. To monitor the effect of such changing climate, we are engaged with long-term monitoring of vegetation throughout the country, in collaboration with the University of Hamburg and the Gobabeb Research and Training Centre. For the purpose of long-term monitoring we have 21 biodiversity observatories throughout the country on which we regularly resurvey the plant biodiversity. These biodiversity observatories are supplemented by a number of auxiliary observatories, in which we can monitor for very specific purposes like erosion, specific plant species and -stands or lichen cover. With the annual monitoring, large emphasis is placed on monitoring using repeat aerial photography using state-of-the-art UAV technology. This technology is also used for specific applications like mapping and monitoring alien invasive species stands, stands of endemic species, as well as monitoring erosion features, and the success rate of the rehabilitation of these erosion features. A special mention is to be made of an application in the mining industry, were we are monitoring the health and success of rehabilitation work at mines with UAV technology. With the UAV technology I am combining the interesting fields of botany, vegetation ecology, remote sensing and GIS into one. I am also a keen photographer of plants and landscapes, and have contributed extensively to online plant identification guides as well as for field identification guides in the past.

WF Adank, Namibia University of Science and Technology

Lecturer: Nature Conservation Techniques, Department Agriculture and Natural Resources Sciences, NUST

ME Coetzee, Namibia University of Science and Technology

Senior Lecturer: Department of Architecture and Spatial Planning, NUST

Additional Files

Published

2019-08-22

Issue

Section

Section A: Research articles