1817-1862 1948- aspectdel'environnement biographies biography biologistes biologists brianj canada citizenparticipation concordrivervalley conservation coursd'eau cross-culturalstudies customarylaw dams drainage ecology ecosystemmanagement environmentalaspects environmentalaspectsofdrainage environmentalaspectsoffloodcontrol environmentalconditions etc fisheries floodcontrol handbooks harvey henrydavid manuals maori(newzealandpeople) massachusetts newzealand northwest oregon pacific pennsylvania pollution pêches riparianecology rivers sociallifeandcustoms streambankplanting streamecology thoreau unitedstates valleycreek water watershedrestoration waterways écologiedescoursd'eau