The plant communities of the Andover Game Reserve, South Africa

Abstract

Floristic characteristics of the Andover Game Reserve (AGR) were surveyed using an area-based survey technique and classified according to the data recorded from 88 relevés, using the PHYTOTAB-PC software package. Three plant communities, of which two each contain two variants, were described and mapped. The plant communities and their causative environmental factors were validated through detrended- and canonical correspondence multivariate analyses. The plant communities of the AGR were found to typify the floristics associated with the catenal sequences located in undulating areas on granite. Broad-leaved savanna is located at the crest and upper mid-slopes while fine-leaved savanna occurs along the footslopes of the AGR. Seeplines, a characteristic occurrence along catenas, are found at the transitional zone between the upper broad- and lower fine-leaved savanna plant communities. This study forms the basis for the compilation of a revised ecological management plan for the Andover Game Reserve

Edaphic, structural and physiological contrasts across Amazon Basin forest-savanna ecotones suggest a role for potassium as a key modulator of tropical woody vegetation structure and function

“…Of course, we are by no means suggesting that all observed variations in tropical vegetation structure should be explainable on the simple basis of the CWAK hypothesis. For example, there are numerous cases where poor drainage may be the reason for savanna vegetation types under conditions otherwise suitable for forest (Cole, 1960(Cole, , 1986Haase and Beck, 1989;Cronje et al, 2008;Mantlana et al, 2008;Cochrane and Cochrane, 2010), and it also seems reasonable to speculate that in some cases woody savanna tree extent could be constrained by supra-low calcium concentrations in the subsoil (Cochrane, 1989). Also, with sodium capable of replacing potassium in many of its physiological functions when available at moderate concentrations (Wakeel et al, 2011;Kronzucker et al, 2013), of considerable interest in terms of refinement of the CWAK hypothesis is the existence of very high biomass stands of Colophospermum mopane (J.Kirk ex Benth.)…”

Edaphic, structural and physiological contrasts across Amazon Basin forest–savanna ecotones suggest a role for potassium as a key modulator of tropical woody vegetation structure and function

“…Of course, we are by no means suggesting that all observed variations in tropical vegetation structure should be explainable on the simple basis of the CWAK hypothesis. For example, there are numerous cases where poor drainage may be the reason for savanna vegetation types under conditions otherwise suitable for forest (Cole, 1960(Cole, , 1986Haase and Beck, 1989;Cronje et al, 2008;Mantlana et al, 2008;Cochrane and Cochrane, 2010), and it also seems reasonable to speculate that in some cases woody savanna tree extent could be constrained by supra-low calcium concentrations in the subsoil (Cochrane, 1989). Also, with sodium capable of replacing potassium in many of its physiological functions when available at moderate concentrations (Wakeel et al, 2011;Kronzucker et al, 2013), of considerable interest in terms of refinement of the CWAK hypothesis is the existence of very high biomass stands of Colophospermum mopane (J.Kirk ex Benth.)…”

Seasonality of hydraulic redistribution by trees to grasses and changes in their water‐source use that change tree–grass interactions

“…The study was carried out in the 7100 ha Andover Game Reserve (Andover GR), South Africa, located between 24°3 3′ S and 24°38′ S, and 31°10′ E and 31°17′ E. The annual rainfall is 550-650 mm (Cronje et al, 2008), and the precipitation occurs in summer, starting in the dry-wet transition season (Oct/Nov), and ending in the wet-dry transition season (Mar/April/ May; Figure 1). …”