1 Associação Portuguesa dos Recursos Hídricos ALTERAÇÕES DA QUALIDADE BIOLÓGICA ASSOCIADAS À CONSTRUÇÃO DE PEQUENOS APROVEITAMENTOS HIDROELÉCTRICOS Paulo Jorge PINHEIRO               ! "# $ %  & ’()*%+,+  %-. //01-"/ Francisco Nunes GODINHO 2   3--         ! "# $ %  & ’()*%+,+  %-. 401-"/ João Manuel OLIVEIRA 2   3-- 567 % 5  689   - %  7- 8  :%%  - 2   ! )***%,’’ ;- - %-. <-80"/ Filipa Monteiro REIS            ! "# $ %  & ’()*%+,+  %-. 4-/01-"/                                      ! " #       #     $  %    &    ! ’ # #      &     ! ’ (  )          #   * %  *  ! ’    +  #     )          #  %  * ,"-.    %/ # +   *   ! 0     12 3"4    #           "-! 1    3551    1      6    +! " +#   6             !  +#         * "