The value of urban and peri-urban conservation efforts within a global biodiversity hotspot

Lyle E Ground,Rob Slotow,Jayanti Ray-Mukherjee

doi:10.4102/abc.v46i2.2106

Abstract

Background: Systematic conservation planning (SCP) is a key tool in conservation prioritisation. It has recently been applied within the eThekwini Municipal Area (EMA), South Africa, a rapidly developing metro located within a biodiversity hotspot. Most vegetation types within this region are threatened, yet have received limited scientific attention. Objectives: To assess forb biodiversity of coastal and near-coastal grasslands and contextualise potential drivers of species variation to the EMA context. Method: We quantified forb species richness, frequency and species composition, determined the variation of these amongst plots and sites, and assessed which variables were responsible for this variation. Results: Site forb species richness ranged from 33 to 84 species per site, with the most frequent species differing across the seven sites. Beta diversity was higher across than within sites. Distance to the closest traditional medicine market and site perimeter-to-area ratio were the greatest drivers of species richness, whilst altitude, aspect, mean temperature and rainfall seasonality were the main contributors to species composition patterns. Conclusion: SCP can use key environmental and climatic categories to improve selection of grasslands to maximise both species richness and variation in species composition. A more fine-scale systematic conservation plan will, in turn, provide a more robust basis for development decisions. The outcomes illustrate the importance of urban and peri-urban conservation efforts, including fine-scale conservation planning, in contributing to regional, national conservation targets.

Highlights

Conservation planning and sustainable environmental management have limited resources for implementation owing to competition with other socio-economic imperatives (Heywood & Iriondo 2003; Shankaran 2009; Schneider et al 2011)
Prioritisation of areas for conservation, through systematic conservation planning (SCP), has become a key tool in conservation resource allocation (Heywood & Iriondo 2003; Margules & Pressey, 2000; Pressey, Cowling & Rouget 2003). These algorithm-based planning tools use available data on habitats, species and ecosystem services to select priority sites based on important criteria (Margules & Pressey 2000)
SCP outputs are only as good as the input data (Heywood & Iriondo 2003; Margules & Pressey 2000; Smith, Goodman & Matthews 2006), and conservation plans are often based on limited data, which requires conservation planners to define different environmental features by using environmental breaks or changes

Summary

Introduction

Conservation planning and sustainable environmental management have limited resources for implementation owing to competition with other socio-economic imperatives (Heywood & Iriondo 2003; Shankaran 2009; Schneider et al 2011). SCP outputs are only as good as the input data (Heywood & Iriondo 2003; Margules & Pressey 2000; Smith, Goodman & Matthews 2006), and conservation plans are often based on limited data, which requires conservation planners to define different environmental features by using environmental breaks or changes (termed mesofilters; Crous, Samways & Pryke 2013) These ‘surrogate’ habitats are assumed to be representative of a set of species known to occur within them (Crous et al 2013; Smith et al 2006). Most vegetation types within this region are threatened, yet have received limited scientific attention

Objectives

Methods

Results