Environmental groups have welcomed President Rousseff’s veto of key articles of the legislation, but warned that it remains to be seen how effective enforcement of the new law will be. The veto was on key articles which would have reduced requirements upon landowners to maintain forest cover, lifted restrictions on forest clearance near rivers and given an amnesty to landowners who had carried out deforestation prior to 2008 – an article which the Union of Concerned Scientists warned would have set a dangerous precedent encouraging landowners to continue with forest clearance on the assumption that further amnesties would follow in the years to come.