Cendrero, Antonio
established by comparison with the total extent of protected areas in the province. Data input for this assessment comes
from the maps of protected areas and of integrated morphodynamic units.
Fig. 4 shows that alternative 2 affects 5.000 m? of protected area. This represents 0.12 % of all protected area in the
province. If fragmentation is considered, it can be assumed that the total of this protected area will be damaged; this
would represent 0.36 % of the total for the province.
4.3 Sites of gomorphological interest
The value of these sites can be expressed using different methods and criteria (Dur n, 1998; Poli, 1999). Impacts on
SGIs have a quantitative (number of sites affected) and a qualitative (value of the site and degree of damage) aspect. A
series of parameters (Table 2) are used to establish the value of a site, before and after construction of the motorway.
Details on the precise method of calculation of impacts are given by Rivas et al. (1997).
Impact for one SGI (i):
Iscri ^ VsGti(post) — VGli (pre)
Total impact on SGI s = X Isaıi
Where: V represents the value of the SGI and n represent the number of SGIs affected by the motorway.
SGI Typ |C|A|E|K Ex! D|Ac| O| S|H |Aec | Q| P |Vser
Si pee | Foided | 4 | 2,12 | 1191.01 94191314 | 1 7
structure
81 post | Folded 2:12.11 11ologloli2l41l15 4 4 | 12 | 0.83
structure
49 pre Pillow | 3 | 3 | 3 1!0}101 0] 4 | 2 | 3 4 7 | 14 [1.75
Lava
49 post| Pillow | ! 3 12-11 |.0 | 0 | © | 2.|.4 3 4 6 | 12 | 0.5
lava
42 pre | Terrace | 4 | 3 21112»1111:11|24413151.4.|[9 15 {2.75
42 post | Terrace | 2 | 3 011107010107131]131. 414 10 | 0.75
C: state of conservation; A: relative abundance; E: extent; K: degree of knowledge; Ex: good example of processes;
D: diversity; Ac: activities; O: conditions of observation; S: availability of services; H: number of inhabitants
(constant); Acc: accessibility; Q: quality of the SGI; P: potential for use; Vsar: value of SGI (Vscı = C (2Q + P) / 48).
Table 2. Example of application of SGIs database to impact calculation.
Alternative 1: no sites affected.
Alternative 2: V 81 (post) + V 49(post) x V 4o(post) — Vs l(pre) — V 49(pre) = V apre) = —441
It is obvious that in the example shown the least impacting route corresponds to alternative 1. The significance of
impacts on SGI is not easy to express in other terms; comparison of the impact values obtained with those.
corresponding to the destruction of well-known geological-geomorphological landmarks or sites in the region is
considered an appropriate procedure.
International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000. 247
