Landscapes Forest and Global Change - ESA - Escola Superior ...

M.G.C. Martins & J. Aranha 2010. Electrical network hazard assessment for the avifauna in Portugal
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In a second stage, the GIS was updated with information concerning:
• Portuguese electrical network
• Portuguese Roads network
• Settlements Location
• Land use and land cover map
• Digital Elevation Model
In the third stage, using 3D Analyst and Spatial Analyst Tools, the recorded information was
processed in order to calculate:
• Land slope and aspect
• Distances to water bodies
• Distance to road network
The fourd stage was dedicated to geodata analysis and multivariate statistics calculation. They
were used Principal Components Analysis, Cluster Analisys and Geostatistical Analysis, in
order to stablish a relationship between the Portuguese electrical network (high and middle
power), environmental characteristics and the birds’ wildlife conservation (Morrison, 1991;
Reis, 1997; Hoef et al, 2001; Soares 2006).
Results from previous present stages were, then, used to create collition and electrocution
hazard maps for IBAs and SPAs
3. Result
Results from data management shown that the frequency of deaths is higher in Steppe land and
Agroforestry areas. Tables 1 and 2 summarizes all deaths by type of habitat and electrical power
line hazard level.
Table 1: Deaths by type of habitat
Habitat (class code) Total (n) %
Steppe (1) 110 28.06
Shrub land (2) 32 8.16
Forested land (3) 51 13.01
Inland wetlands (4) 16 4.08
Coastal wetlands (5) 5 1.28
Agroforestry mosaic (6) 174 44.39
Other (e.g. bare soil) (7) 4 1.02
Total 392 100.00
Results from Principal Components Analysis revealed a positive correlation between the
number of deaths and the number of power line network planes and a negative correlation to
distance to roads. This could indicate that the "mortality rate" increases as "distance to roads,"
decreases because power line network is often parallel to road network and birds need to cross
roads for feeding in around land.
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.