Wassenaar, TD & van Aarde, RJ 2008, 'Towards Better Restoration Assessment — A Review of the Bioindicator Concept in Rehabilitation', in AB Fourie, M Tibbett, I Weiersbye & P Dye (eds), Mine Closure 2008: Proceedings of the Third International Seminar on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 785-798, https://doi.org/10.36487/ACG_repo/852_73
(https://papers.acg.uwa.edu.au/p/852_73_Wassenaar/)
Abstract: It is widely accepted that a comprehensive ecologically-based monitoring programme is critical to the 
success of mine (and other) rehabilitation projects. But monitoring ecosystem development can be an 
expensive exercise – it requires specialist input and usually takes more time and money than expected in an 
industrial environment. These problems may be addressed through the use of bioindicators, especially when 
rehabilitation focuses on biodiversity conservation and on mitigating impacts on biodiversity. In lieu of 
sampling whole ecosystems, surrogate measures of structure, composition and function on several 
organizational levels (bioindicators) are commonly used as part of a comprehensive strategy of risk analysis 
for an ecosystem. Indicators are widely viewed as a cost-efficient tool, and are accepted and understood on a 
policy level. However, indicators should meet certain empirical and theoretical requirements related to their 
ecological meaning and sensitivity. A key feature therefore characterizes their use: indicators should be 
tested for their surrogacy. Assessing success in ecological restoration is obviously closely related to the 
indicator concept, as emphasized by the SER’s criteria for success. However, restoration practice has 
always emphasized a ready-to-hand set of community variables, with little thought for their appropriateness 
or efficiency. We critically reviewed restoration assessment papers, evaluating how their assessment 
methodology measures up against criteria related to the effectiveness of indicators. We found that 61% of the 
studies used indicators that were compared to reference systems (a key requirement for surrogacy), but only 
29% used previously tested indicators, only 2% of those tested the indicator for precision and only 19% 
tested species’ functional affinity to specific habitats. We suggest that the explicit testing of indicators will 
increase the effectiveness of restoration assessments and contribute to better practice in ecological 
restoration of mined land.