Biodiversity and Conservation

, Volume 25, Issue 4, pp 725–737 | Cite as

Past and present disturbances influence biodiversity value of subtropical grassland ecological networks

  • Lize Joubert
  • James S. Pryke
  • Michael J. Samways
Original Paper


The effect of transforming natural habitat to commercial land uses can be mitigated by implementing ecological networks (ENs) in production landscapes. However, EN ability to conserve biodiversity is potentially influenced by past and present disturbances, and spatial configuration of habitat patches. Here, we investigated how plant assemblages of a subtropical EN in a timber production landscape in South Africa respond to disturbance history (i.e. natural vs. recovering after removal of Pinus spp.), mowing in firebreaks (i.e. 30 m wide grassy strips intended to stop spread of fires in plantations), and three design parameters: corridor width, distance to protected area boundary, and context i.e. proportion eucalypt compartments within 500 m radius. Reference sites were in the adjacent iSimangaliso Wetland Park, a protected area (PA). Past disturbances and the current practice of mowing in firebreaks significantly influenced plant species composition, but not plant species richness. Plant dominance was greatest in mowed firebreaks, but similar between natural and recovering grassland. None of the design variables affected plant species richness, or composition. However, dominance was significantly and negatively correlated with corridor width, and positively correlated with context. Hence, sites are ordered in terms of their biodiversity value from greatest to lowest: natural areas > recovering areas > firebreaks. Based on these results, natural grassland in wide, well-connected corridors should have greatest conservation priority. We recommend that past disturbances, and current management practices should be taken into account and integrated into the design of future ENs. Such an approach is necessary for effective biodiversity conservation in production landscapes.


Firebreaks Mown Plantation forestry Recovering grassland 



We thank M. Stofberg for field assistance; J. Shuttleworth, G. and M. Kruger, and the Monzi community (specifically the Oscrofts, Lonsdales, and Grooms) for providing maps, accommodation at field sites, technical assistance, practical advice and local knowledge; R. van Wyk for assistance with identification of plants; SiyaQhubeka Forests Ltd. for allowing sampling on their property; and Ezemvelo KZN Wildlife for permits (OP 2678/2012). Financial support was from the Mondi Ecological Network Programme (MENP) and the National Research Foundation (NRF), South Africa (Grant No: 78652). Any opinion, findings and conclusions or recommendations expressed in this material are those of the authors. Therefore, the NRF do not accept any liability in regard thereto.

Supplementary material

10531_2016_1088_MOESM1_ESM.docx (22 kb)
Supplementary material 1 (DOCX 22 kb)


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Copyright information

© Springer Science+Business Media Dordrecht 2016

Authors and Affiliations

  1. 1.Department of Conservation Ecology and EntomologyStellenbosch UniversityStellenboschSouth Africa

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