A Dendrochemical Survey of Sugar Maple ( Acer saccharum Marsh) in South-Central Ontario, Canada

摘要: A dendrochemical survey of sugar maple (Acer saccharum Marsh) was conducted insouth-central Ontario, which encompassed twenty-two sites in areas that both exceeded orwere below the published Critical Loads with respect to acid deposition. Areas thatexceeded Load were located remote from point emission sources, but alsocharacterized by thin, nutrient-poor soils overlying Precambrian Shield. ThepHaq surface (A-horizon) lower at on Shield andwater-extractable concentrations Ca decreased exponentially decreasing soil pH. Significant polynomial relationships between pH and growth,assessed as cumulative tree-ring growth 1949 1998, explained 40% 37% ofthe variation respectively, lowest associated lowsoil low Ca. Furthermore, there a significant linearrelationship wood (averaged 1998) pHand several trace elements (Mn, Pb, Zn, Cd, Sr Rb) greater atlow Poor andhigh Al levels, together accounted for 43% maplegrowth multiple regression model. None other chemistry variablescontributed significantly These data suggest grows poorlyon acidic high levels. Although such podzols occurnaturally some Shield, if losses due aciddeposition and/or harvesting exceed inputs through weathering deposition(i.e. Load), may be adversely affected ultimately lead toincreased incidence decline.