Mistbelt grassland fragmentation in the Umvoti conservancy, KwaZulu-Natal,

Winter, S; Morris, CD

Mistbelt grassland fragmentation in the Umvoti conservancy, KwaZulu-Natal,

2004

Winter, S | Morris, CD

The existing Mistbelt grassland in the Umvoti Conservancy in KwaZulu-Natal is highly fragmented due to intensive agricultural land use (plantations and pastures), with Mistbelt grassland now occupying less than 3.5% of the area. Patch sizes range from a few hectares to less than 350ha in extent. The plant species composition of remnant patches was sampled and classified using TWINSPAN, and sward structure described in terms of basal cover, sward height, sward density, and aerial cover. Grassland patches were of two main types: (i) Themeda triandra grassland with dense basal cover and high species richness (19.4 ± 1.77 species); and (ii) secondary grassland characterised by the absence of T. triandra and a high frequency of Hyparrhenia hirta. The species richness of the disturbed patches, particularly those in wetter areas, was poor (12.4 ± 1.27 species). Arisitida junciformis was ubiquitous and has the potential to invade all grassland patches in the absence of appropriate fire and grazing management. Various numerical indices, calculated using FRAGSTATS, were used to quantify landscape heterogeneity. The question of connectivity was addressed by sampling a powerline servitude, which is a potential corridor through the area. This corridor could also possibly serve as a link through the conservancy between the adjacent Blinkwater Nature Reserve, which contains 492ha of pristine Mistbelt grassland, and the lower-lying Umvoti Vlei. South African Journal of Botany 2001, 67 (2): 303–311

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