%0 Journal Article
%T Abundance and Structure of African Baobab (Adansonia digitata) across Different Soil Types in Gonarezhou National Park, Zimbabwe
%A Clayton Mashapa
%A Patience Zisadza-Gandiwa
%A Edson Gandiwa
%A Shakkie Kativu
%J International Journal of Biodiversity
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/874713
%X This study investigated the abundance and structure of African baobab (Adansonia digitata) across soil group strata in Gonarezhou National Park, Zimbabwe. The study was based on a stratified random sampling design composed of the following soil group substrates: (i) granophyres, (ii) malvernia, and (iii) rhyolite. Belt transects of £¿km were randomly laid across soil group. Baobab abundance and population structure were determined from the density and size class distribution, respectively. There were significant differences in plant height and plant density across Gonarezhou soil groups. Study sites on granophyres derived soil group indicated viable abundance and recruitment of baobab population. Whereas the study highlighted a concern over the unbalanced size structure distribution of baobab population on malvernia derived soil group, our results indicated that baobabs are in danger of extirpation on malvernia derived soil group. Baobab community in Gonarezhou tends to occur more densely along environmental gradient of soil group type as influenced by the underlying geological soil substrate of granophyres. Malvernia derived soil group is likely less ideal for baobab recruitment. 1. Introduction Plant species distribution is usually modeled as a function of climatic, geologic, or edaphic variables, which are postulated to exert a prominent effect on species¡¯ natural distribution [1, 2]. The stability and complexity of large expanses of woodlands in semiarid savanna in face of soil resource gradient continue to stimulate debate on plant species regeneration concept [3]. In Gonarezhou National Park (hereafter, Gonarezhou), Zimbabwe, soil group variation is perceived as a determinant for African baobab (Adansonia digitata) abundance and spatial population structure distribution, as soil group resource type may compensate or aggravate climatic aridity as well as soil nutrient availability. Landscape-scale variation in woody vegetation may primarily relate to soil group nutrient resources [4]. In recent years, baobab population seems to show unusually low recruitment in central parts of Gonarezhou, despite low elephant (Loxodonta africana) density [5] and low fire frequency [6] within the central Gonarezhou. This phenomenon is associated with likely future local extirpation of a species. Such a trend deserves investigation and monitoring. Baobab is a key note species of ecological significance in the savanna ecosystem, and thus it is a protected species in South Africa [7]. In Zimbabwe, baobab is confined to semi-arid low altitude areas [8]. It provides
%U http://www.hindawi.com/journals/ijbd/2013/874713/