Metals in bulk deposition and surface waters at two upland locations in northern England.

摘要: Concentrations of aluminium and minor metals (Mn, Ni, Cu, Zn, Sr, Cd, Ba, Pb) were measured in precipitation surface water at two upland locations (Upper Duddon Valley, UDV; Great Dun Fell, GDF) northern England for 1 year commencing April 1998. At both locations, the loads bulk lower ends ranges reported other rural remote sites, period 1985–1995. The deposited mostly dissolved form, their concentrations tended to be greatest when rainfall volumes low. Zn Pb deposition correlated (r2⩾0.40) with non-marine sulphate. Three streams, ranging mean pH from 5.07 7.07, organic carbon (DOC) <1 mg l−1, monitored UDV, pools (mean 4.89 6.83, DOC 22 15 l−1) GDF. Aluminium mainly following (means 49–51 samples, μg l−1): Al 36–530, Mn 4.4–36, Ni 0.26–2.8, Cu 0.25–1.7, 2.1–30, Cd 0.03–0.16, Ba 1.9–140, 0.10–4.5. generally higher Differences metal between waters each location, temporal variations individual waters, can explained qualitatively terms sorption solid-phase soil matter mineral surfaces, complexation transport by DOC, chemical weathering. UDV catchments are sinks sources Al, Mn, Ba. GDF Other approximately balance. Comparison metal:silicon ratios values silicate rocks indicates enrichment substantial Pb. These enrichments, together high past, make it likely that governed release catchment atmospherically-deposited metal. appear responding on a time scale decades, possibly centuries, changes deposition. For more acid calculated free-ion similar published LC50 acute toxicity towards fish. all one-to-four orders magnitude than