. Results
4.1. Land-use and land-cover change 1978–2008
The Revised Forest Law of 1987 started a period of rapid shift in
land use from pasture to plantations. The greatest impact of the establishment
of plantations is on grasslands, where the change in biota is
total. Our analysis of satellite images and the Stora Enso GIS plantation
database showed that in 1990 the land cover proportion of plantations
was 0.6% of the total land area; by 1999 this figure had
increased to 4.5%, and in 2008 plantations covered 10.6% of the terrestrial
study area, consisting of 41.7% pine and 58.3% eucalyptus
(Table 2; Fig. 3). The earliest plantations were mostly pine.
In 1987 the study area contained 564 cattle-shelter forest stands,
around which pastures and grasslands for cattle grazing could be
found. By 2008 this figure had decreased to 524, suggesting that the
area available for cattle herding had likewise decreased by 7.1%. The
area of riparian forests decreased slightly (5.8%) from 1987 to 2008. Significant
changes in water bodies were observed due to the construction
of hydroelectric dams on the Rio Negro 1987–2008: The lake area was
almost doubled (an increase of 43.6%)