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A correlation was found between total Fe, Mn and P in Lake Muskoka sediments,Ontario (Brydges, 1970). Similarly changes in pH and redox conditions have majoreffects on the solubility of manganese.SULPHIDEPrecipitation of some heavy metal sulphides in flooded soils and sediments is animportant mechanism regulating the solution concentration of S 2- and the metal ionsFe 2+ , Mn 2+ , Zn 2+ , Cu 2+ and Hg 2+ . Under anaerobic conditions these sulphides were foundto be very stable (Engler and Patrick, 1975).Sulphide reducing and methane producing bacteria in the bottom deposits offresh water lakes appear to play an important role (Cappenberg, 1974). The sulphatereducers were most abundant at the 0-2 cm depth, producing H 2 S, with methaneproducers at 3 to 6 cm depth. The sediment in the deepest part of the lake were blackin colour due to precipitated iron sulphide.PHOSPHATEThe phosphate mineral apatite (Ca 5(PO 4) 3F(Cl,OH) occurs in Great Lakespost-glacial sediments. Vivianite (Fe(PO 4 ) 2 8H 2 O) is important in controlling aqueousphosphate concentration and often occurs in sand size nodules (Dell, 1973). Brydges(1970) suggested iron was the most important release factor for Lake Muskoka (Ont.)sediments under anaerobic conditions. Lead phosphates are present in soils ofintermediate pH, lead sulphate in very acid soils. and lead carbonate above pH 719
(Lindsay, 1973).The presence of lead phosphate crystals in corn leaves heavily contaminatedwith lead was established by scanning electron microscopy with nondispersive X-rayemission (National Research Council, 1974).DISTRIBUTION OF METALSA. WITH PARTICLE SIZE:Heavy metals are often associated with finer sediment grain size (Thomas,1972; Oliver & Agemian, 1974). In the Great Lakes, concentration and distribution ofsediment bound mercury is intimately associated with sediment type (Thomas, et al,1973; Thomas, 1974; Hartung, 1974). When corrected for the quartz content of thesediment, a realistic assessment of mercury concentration in the fine particulates wasobtained (Thomas et al, 1973; Thomas, 1974). In a study of Ottawa River sediments,the sorption capacity for mercury was 99x for the 0.45 to 38 µ fraction than for sandranging from 100 to 150 µ (Townsend et al, 1974). Wood fibres had a greater capacityfor mercury than the sand fraction. Similarly, hydrochloric acid extractable cadmiumand chromium were higher in the fine grained sediments of the Lower Mississippi(Hartung, 1974).The correlation between iron concentration and grain size for Ottawa Riversediment was noted earlier (Rust and Waslenchuk, 1974) The greatest contrastbetween anomalously high and background levels for heavy metals was found byanalyzing the -80 mesh fraction (Hawkes and Webb, 10-20 cm of lake sediment andsuggested that bacteria generated gas bubbles forming extremely reactive surfaces20
Page 1 and 2: THE APPLICATIONS OF CHEMICALANALYSE
Page 3: THE APPLICATIONS OF CHEMICAL ANALYS
Page 6 and 7: Sediments and soils play important
Page 8 and 9: An understanding of physical, chemi
Page 10 and 11: Transportation of natural and man-m
Page 12 and 13: operation. Wastewater is a major so
Page 14 and 15: Chaney et al (1972) studied iron up
Page 16 and 17: near a large zinc smelter in Japan
Page 18 and 19: Lead in soil is relatively unavaila
Page 20 and 21: Of interest is the form of chromium
Page 22 and 23: appreciably available. In acid soil
Page 26 and 27: could cause uni-directional migrati
Page 28 and 29: mobile through chelation with humic
Page 30 and 31: The surface 5 cm of sediment from M
Page 32 and 33: Organic matter content of soils has
Page 34 and 35: Pyritic sulphur content, measured a
Page 36 and 37: Organic carbon can be measured by c
Page 38 and 39: previously disposed of in open wate
Page 40 and 41: eference samples are included in ea
Page 42 and 43: investigated based on HNO 3 HClO 4
Page 44 and 45: Ignition loss at 350-400°C has bee
Page 46 and 47: Ministry of the Environment and nut
Page 48 and 49: (total N and P, and Loss on Ignitio
Page 50 and 51: IDENTIFICATIONSAttempts are made to
Page 53 and 54: REFERENCESALLAN, R. J., 1974. Metal
Page 55 and 56: Air and Waste Chemistry. Amer. Chem
Page 57 and 58: GORHAM, E., and SWAINS, D. J., 1965
Page 59 and 60: JOHN, M. K., 1972. Cadmium Adsorpti
Page 61 and 62: Harvest, Location and Level of N an
Page 63 and 64: Sudbury Lake. Ontario Ministry of t
Page 65 and 66: UNDERWOOD, E. J., 1971. Trace Eleme

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