Appraisal of environmental impacts and mitigation measures through mathematical matrices

Interaction matrices are widely used in environmental impact assessments (EIAs). However this technique is considered an illustrative approach, since its analytical power is deemed to be insufficient for effectively handling complex decision-making. It can be argued that the misuse of interaction matrices has (in some instances) contributed to flawed EIAs, which have been deliberately misrepresentative and have been used for endorsement of projects. Consequently an alternative for better EIAs in the short term is to enhance the matrix approach, so that a more rigorous evaluation of impacts can be achieved. The approach presented here is based upon mathematical matrices to determine the significance of impacts; specifically it encompasses the use of minimum link matrices, interpretative structural models and exponential and linear equations. This method allows users to systematically weight all possible cause-effect interactions and pathways, and to consider primary and secondary impacts identified in a matrix. Consequently, the approach increases the effectiveness and rigor of matrices in handling complex data and predicting environmental impacts in a strict and traceable way. (C) 1998 Academic Press.