Leopold Matrix

This approach is used in numerous methods. Because the assessor intends to be all-inclusive, however, the sets are usually much too large for visual comprehension. In the Leopold matrix [10,74-75], for example, 17,600 pieces of information are displayed. Such an array may confuse the decision-maker, particularly if a separate checklist or matrix is prepared for each alternative. Effort may be wasted if the environmental impact assessor conscientiously tries to fill in a high proportion of the boxes, and he may be swamped with excessive information if he succeeds. 

Three general approaches, selected because they represent a range of options for impact assessment, are discussed in this section. These include the Leopold Matrix, Overlays, and the Battelle environmental evaluation system. The following is a summary. 

The pioneering approach to impact assessment, the Leopold Matrix, was developed by Dr. Luna Leopold and others of the United States Geological Survey [6,10,74-75]. The matrix was designed for the assessment of impacts associated with almost any type of construction project. Its main strength is as a checklist that incorporates qualitative information on cause-and-effect relationships, but it is also useful for commimicating results. 

Table 3 The Leopold Matrix (Part I lists the project actions, arranged horizontally in the matrix and Part 2 lists the environmental characteristics and conditions, arranged vertically in the matrix)...

The Leopold Matrix is comprehensive in covering both the physical-biological and the socio-economic environments. The list of 88 environmental characteristics is weak, however, from the point of view of structural parallelism and balance. 

The Leopold Matrix is not selective, and includes no mechanism for focusing attention on the most critical human concerns. Related to this is the fact that the matrix does not distinguish between immediate and long-term impacts, although separate matrices could be prepared for each time period of interest. 

The principle of a mutually exclusive method is not preserved in the Leopold Matrix, and there is substantial opportunity for double counting. This is a fault of the Leopold Matrix in particular rather than of matrices in general. 

Objectivity is not a strong feature of the Leopold Matrix. Each assessor is free to develop his own ranking system on the numerical scale ranging from 1 to 10. 

The Leopold Matrix contains no provision for indicating uncertainty resulting from inadequate data or knowledge. All predictions are treated as if certain to occur. Similarly, there is no way of indicating environmental variability, including the possibility of extremes that would present unacceptable hazards if they did occur, nor are the associated probabilities indicated. 

The Leopold Matrix is not efficient in identifying interactions. However, because the results are summarized on a single diagram, interactions may be perceived by the reader in some cases. 

The Leopold Matrix employs weights to indicate relative importance of effects and impacts. A weakness of the system is that it does not provide explicit criteria for assigning numerical values to these weights. 

By providing a visual display on a single diagram, the Leopold Matrix may often be effective in commimicating results. However, the matrix does not indicate the main issues or the groups of people most likely to be affected by the impact. 

Table 5 Comparison between the Leopold Matrix, Overlays and Battelle environmental evaluation approaches ...

Smole, S. C. King, L. A. Leopold, P. E. Arbeit, R. D. Sample preparation of Grampositive bacteria for identification by matrix assisted laser desorption/ionization time-of-flight. J. Microbiol. Meth. 2002, 48,107-115. 

The Leopold system is an open-cell matrix containing 100 project actions along the horizontal axis and 88 environmental characteristics and conditions along the vertical axis. These are listed in Table 3. The list of project actions in... 

Leopold et al. (1971), in response to the National Environmental Policy Act of 1969, were the first to suggest using a matrix method for EIA. Basically, matrices combine a checkhst of environmental conditions likely to be affected with a list of project activities, the two lists arranged in the form of a matrix. The possible... 

The way this problem could be tackled using fuzzy linguistic variables is illustrated with the problem takeii from Leopold et al [81] and concerns the impact of a phosphate mining scheme. The assessments made by the authors are reinterpreted as fuzzy variables, minute, very small to enormous, as shown in Fig. 6.8. The upper left hand variable in any box in the matrix (Fig. 6.7) represents... 

Conway GC, Smole SC, Sarracino DA, Arbeit RD, Leopold PE. Phyloproteomics species identification oiEnterobacteriaceae using matrix-assisted laser desorption/ionization time-of-flight mass speetrometiy. J Mol Microbiol Biotechnol. 2001 3(1) 103-12. 

Pahner-Toy, D.E., Sarracino, D.A., Sgroi, D., LeVangie, R. and Leopold, P.E., Direct acquisition of matrix-assisted laser desorption/ionization time-of-flight mass spectra from laser capture microdissected tissues. Clin. Chem., 46, 1513-1516 (2000). 

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