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4.5 Impact Categories, Impact Indicators and Characterisation Factors  223

               for hunting, is mostly ‘fostered’, that is, only hunted at certain times and fed on
               in the winter. Such activities belong to the technosphere. Similar considerations
               are valid for the fishery in rivers and lakes. Too large game populations imply
               substantial damage to vegetation and these animals do not belong to species
               threatened with extinction. Non-fostered wild game and those, which inspite of
               protective regulations are illegally poached can belong to threatened species. In
               general, animals and plants in nature with a high commercial value are threatened,
               for example, as hunting trophies, nutrition, source for medical active substances
               or for certain cultural or superstitious practices. The quoted subchapter of the final
               report of the second SETAC Europe working group ‘Impact Assessment’ 115)  besides
               a detailed discussion of the protection goal provides a list of animals and plants,
               threatened with extinction (extreme case) by overfishing, or by a drastic population
               decrease, and so on. These species are, if relevant for a specific LCA, to be recorded
               in the inventory and subsequently be assessed in the impact assessment as ‘biotic
               resources’. Mueller Wenk estimates that of the many millions of species of (wild)
               animals and plants only some thousands are used by humans as resources and only
               some hundreds (above all, fish and tropical plants) are threatened by direct use.
               The threat to a variety of species by destruction of habitats due to anthropogenic
               land use is not considered. Also Mueller Wenk points to the fact that apart from
               the shortage caused by land use a contribution to a reduction of the variety of
               species or biological variety (biodiversity) is to be considered. 116)  Its impairment is
               an important impact category, unfortunately with no clear indicator yet (see Section
               4.5.1.6), so that it can only indirectly be covered by other categories.
               Impact Indicators and Characterisation Factors
               If to be recorded separately, non-regenerative (finite) biotic resources, for example,
               ecological systems like the tropical rain forest with its specific spectra of species
               can be elaborated with similar impact indicators as discussed for abiotic non-
               regenerative resources. In addition however tables with static ranges would have to
               be present.
                Shortage or scarceness as impact indicator is also valid for regenerative biotic
               resources. Shortage occurs, if withdrawal – globally or in a specific region – exceeds
               generation. For a quantification of regenerative biotic resources their formation rate
               must be known. Contrary to finite resources – which by continuing withdrawal will
               get exhausted in any case, being only a question of time – a sustainable use can be
               achieved for regenerative resources, if the following permanently applies:
                Withdrawal per time unit (world annual consumption) ≤ formation rate
                The natural measure for the scarceness of regenerative resources is thus the
               difference between the world’s annual consumption and the formation rate, related
               to world reserves. In this case the resources scarcity factor R can be computed
                                                               i
               according to Equation 4.8.
                As with abiotic finite resources the world reserves of biotic resources can only
               with difficulty be precisely established. Also the determination of formation rates

               115) Mueller Wenk, in: Udo de Haes et al. (2002).
               116) Koellner and Geyer (2013) special issue land use.
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