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9 Paleolimnological Evidence for Trends in Atmospheric Deposition of Acids and Metals Donald F. Charles and Stephen A. Norton INTRODUCTION Paleolimnological analyses of lake sediments have traditionally been used to reconstruct many aspects of the evolution of lake/watershed ecosystems, including terrestrial and aquatic vegetational succession (Davis et al. 1975), fire history (Patterson 1977), trophic status (Davis and Norton 1978, Stockner and Benson 1967), lake acidification (Battarbee 1984), and even the occurrence of blight or disease (Bradstreet and Davis 1975). Long- term changes in meteorology, morphology of the lake basins, soil characteristics, land use, and surface water chemistry can be partially determined from the sediment record. The sediments of a lake contain information on the lake's past: its biota, water chemistry, watershed characteristics, and material deposited directly from the atmosphere (Frey 1969, Pennington 1981). The information is provided by the organic and inorganic substances, in dissolved or particulate form, that entered or were formed within a lake and were deposited in its sediments. The primary materials are controlled by watershed geology, climate, and biological processes. Once deposited at the bottom of lakes, sediments can be affected by secondary *The introduction and the section on comparison of diatom and chemical data were jointly authored by Donald F. Charles and Stephen A. Norton. D. Charles authored the section on diatoms and chrysophytes. S. Norton prepared the sections on chemical stratigraphy of lake sediments and peat bogs. 335

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336 processes, such as transport (horizontal and vertical) and a variety of chemical and biological activities. Sediments can be sampled by taking cores; the core samples represent the time history of deposition of sediments, with the older sediments lying at greater depth. The times when particular intervals of sediment were deposited can be determined either from analysis of radioactive decay products (lead-210, cesium-137) or by using changes in sediment characteristics that correspond to well-dated local events, such as pollen and charcoal as indicators of logging and forest fires. Nearly all lakes in the Northern Hemisphere, except those in karst topography, were formed by Pleistocene glaciation. Thus, in most lakes in the North Temperate Zone, the stratigraphic record represents the period from formation of the lake to the present (spanning 10,000 to 15,000 years or less). The period of concern in terms of recent anthropogenic acidification is about 50 to 200 years. In lakes with typical sedimentation rates this smaller interval is usually represented within the top one-half meter of sediment, with the time resolution possible in sediment studies depending on the sedimenta- tion rate, extent of mixing, subsampling interval, and type and quality of the dating of the sediment. Resolu- tion may range from 1 year or season for annually laminated (varved) sediment to more than 20 years for lakes with slow sedimentation rates. Several components of sediments provide information on factors related to lake acidification. Concentrations of polycyclic aromatic hydrocarbons (PAHs), soot particles, lead, sulfur, vanadium, sulfur isotope ratios, and mag- netic particles can be interpreted to indicate trends in atmospheric deposition of substances derived from com- bustion of fossil fuels. The pH of lake water during the past can be inferred by analyzing assemblages of diatoms and chrysophytes. Remains of chydorids (littoral crustaceans) and chironomids (midge larvae) may also provide insight into changes in aquatic biota related to acidification. Acidification of lakes and their watersheds can be inferred from changes in concentrations of common and trace metals, such as calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), zinc (Zn), lead (Pb), aluminum (Al), manganese (Mn), and iron (Fe). Various disturbances of watersheds can be indicated by the common and trace metals, pollen, charcoal, and changes in sedimentation rate based on lead-210 dating. IndicatiOnS

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337 of watershed disturbance should be corroborated if at all possible by thorough investigation of historical records and other studies, such as tree ring analysis. Of the above characteristics of sediment, the most information available for acid-sensitive lakes is derived from data on sediment diatom assemblages and sediment chemistry, particularly trace metals. Thus, in this chapter we emphasize these data. DIATOM AND CHRYSOPHYTE SEDIMENT ASSEMBLAGES Analyzing and interpreting sediment diatom and chrysophyte assemblages is the best paleolimnological technique available for reconstructing past lake-water pH. Investigators are using this approach increasingly to assess changes that may have been caused by atmospheric deposition of strong acids, because patterns of change in lake-water pH can be used to help determine trends in acid deposition. Diatoms and Chrysophytes as Indicators of Lake Chemistry Diatoms make up a large group of single-celled freshwater and marine algae (division Bacillariophyta). They have siliceous cell walls and are formed of two halves or valves. Chrysophytes (Chrysophyceae) are primarily freshwater plankton. In this review the term chrysophyte refers to only one family, the Mallo- monadaceae, also known as the scaled chrysophytes. Its members have flagella and an external cell covering of overlapping siliceous scales and bristles. The scales are used for paleoecological reconstructions. The distributions of diatom taxa are closely related to water chemistry (Cleve 1891, Kolbe 1932, Hustedt 1939, Jorgensen 1948, Cholnoky 1968, Patrick and Reimer 1966, 1975, Patrick 1977). For this reason, diatoms are commonly used as indicators of pH, nutrient status, salinity, and other water quality characteristics (e.g., Lowe 1974). Stratigraphic analysis of fossil diatom assemblages can be used to investigate changes in lakes resulting, for example, from shifts in climate, develop- ment of watershed soils and vegetation, local human disturbance of watersheds, and acid deposition (e.g., Battarbee 1979, 1984, Pennington 1981, Fritz and Carlson 1982, Brugam 1983, 1984, Del Prete 1972) .

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338 Diatom assemblages in sediment are good indicators of past lake pH because (1) diatoms are common in nearly all freshwater habitats, (2) distributions of diatom taxa are strongly correlated with lake-water pH (Hustedt 1939, 1927-1966; Meril'ainen 1967; Battarbee lg79, 1984; Gasse and Tekaia 1983; Gasse et al. 1983; Huttunen and Merilainen 1983; Davis and Anderson 1985; Charles 1985a; Anderson et al. in press), (3) diatom remains are preserved well in sediment and can be identified to the lowest taxonomic level, (4) their remains are usually abundant in sediment (104 to 108 valves/cm3 of sediment) so that rigorous statistical analyses are possible, and (5) many taxa are usually represented in sediment assemblages (20 to 100 taxa per count of 500 valves is typical) so that inferences are based on the ecological characteristics of many taxa. Some disadvantages in using diatoms as pH indicators are that (1) diatom identification requires considerable taxonomic expertise, (2) occasionally diatoms are not well preserved because of dissolution (e.g., in some peaty and some calcareous sediments), (3) sometimes the number of taxa is low (e.g., in some bog lakes), (4) calibration data sets (the current relationship between water chemistry and surface sediment diatom assemblages) are not always available for the lake region studied, and (5) good ecological data are not always available for all dominant taxa. Other problems associated with interpreta- tion of diatom data are discussed at the end of this section. In general, the use of chrysophyte scales for pH recon- structions involves the same advantages and disadvantages as for diatoms (Smol 1985a,b; Smol et al. 1984a), except that the number of chrysophyte taxa in a sediment assemblage is in the range of one-tenth the number of taxa of diatoms and most chrysophyte taxa are euplanktonic (normally suspended in the water). The latter character- istic provides an advantage over diatoms in the study of acidic lakes because euplanktonic diatoms are usually rare or nonexistent in lakes with a pH below about 5.5 to S.8 (Battarbee 1984, Charles 1985a). In these cases, chrysophytes may be more sensitive indicators of water chemistry changes than diatoms because they live in direct contact with the open water, whereas most diatoms grow in the shallower water of the littoral zone, which may be chemically different from the open water.

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339 Techniques for Determining pH Trends Several techniques based on diatom assemblages have been used to assess trends in acidification and to derive equations for inferring lake-water pH. These are de- scribed briefly below. Further descriptions and discussion of details and uncertainties associated with the reconstruction of lake-water pH are covered in depth by Gasse and Tekaia (1983), Battarbee (1984), Davis and Anderson (1985), Charles (1985a), and Smol et al. (1985) The simplest and most straightforward approach is to count sediment-core diatom and chrysophyte assemblages and prepare depth profiles of percentages of the dominant taxa. Changes in the profiles are then interpreted in light of the ecological data available on the taxa. At the present time, this is the only technique used to analyze chrysophyte scale data. Hustedt (1939) made one of the first significant steps toward establishing a more quantitative approach for using diatoms as pH indicators. He recognized the strong relationship between diatom distributions and lake-water pH and defined the following pH occurrence categories: Acidobiontic--optimum distribution at pH below 5.5 Acidophilic--widest distribution at pH less than 7 Circumneutral/indifferent--distributed equally above and below pH 7 Alkaliphilic--widest distribution at pH greater than 7 Alkalibiontic--occurs only at pH greater than 7 Assignments of diatom taxa to these categories can be based on literature references and on the distribution of taxa within waters of particular geographic regions. Changes in the percentages of diatom valves in each pH category in a sediment core can be used to estimate trends in lake-water pH. This method makes use of data on most of the taxa within a core, not just the dominant species. Nygaard (1956) took the next major step with the development of a set of indices. These indices are based on ratios of the percentages of diatom valves in Hustedt's pH categories. First, acid units and alkaline units are calculated. acid units = 5 (% acidobiontic) + (% acidophilic), alkaline units = 5 (% alkalibiontic) + (% alkaliphilic)

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340 The percentages of valves in the two extreme pH cate- gories, acidobiontic and alkalibiontic, are arbitrarily weighted by a factor of 5 because diatoms in these categories are presumably stronger indicators of pH. The formulas for Nygaard's indices are acid units a = alkaline units acid units number of acid taxa alkaline units number of alkaline taxa . Of these, index a is the best predictor of current pH in acidic lakes (Merilainen 1967, Davis and Anderson 1985, Charles 1985a; Figure 9.1) and is used most frequently. Renberg and Hellberg (1982) derived a new index (Index B), also based on pH categories: (% indifferent) ~ 5 (% acidophilic) + 40 (% acidobiontic) Index B = (96 indifferent) + 3.5 (% alkaliphilic) + 108 (% alkalibiontic) Index B has advantages over index on, including the use of more information and less reliance on alkaline taxa, which are typically rare or absent in acid lakes. New indices incorporating Hustedt's (1939) pH categories have been developed by Watanabe and Yasuda (1982) and Brakke (1984). Merilainen (1967) refined quantitative techniques even further by developing an approach to predict lake-water pH from the index values. The relationship between tne logl0 of index values and measurements of lake-water pH for several lakes is determined by using regression analysis (e.g., Figure 9.1). Predictive equations are then derived directly from the slope and intercept of the regression equations. Predictive equations can also be developed from multiple linear-regression analysis of measured lake- water pH with the percentages of diatoms in each pH category (e.g., Davis and Anderson 1984, Charles 1985a, Figure 9.2). Other approaches for inferring pH involve the use of multiple regression of selected taxa and

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1 0 9 8 I 7 6 5 4 341 Denmark (Nygaard, 1956) * Finland (Merilainen, 1967) O Norway ( Davis et al., unpublished ) \ * · Adirondacks, U.S.A. ([gel Prete et al., 1972; Schof ield and Ga I loway, 19 77 ) · Northern New England, U.S.A. (Norton et al., 1981 ) pH = ~.73252 (1°91 0 a) + 6.6024 *\ ~ · - ' 0~ - :~^Oo Hi- my- · O * \ ~,0^ . . 8 -amp ~ ^1: 1 ~ -4 -3 -2 -1 0 1 2 3 L°G1 0 0t 4 oo FIGURE 9.1 Logarithm of Nygaard's alpha index for surface sediment diatom assemblages versus lake surface water pH (Norton et al. 1981). Data for Norway are from R. B. Davis, F. Berge, and D. Anderson, University of Maine, Orono, unpublished data. multiple regression of principal components of taxa data sets (Davis and Anderson 1984, Gasse and Tekaia 1983). The standard error for inferred pH ranges between +0.25 and +0.5 pH units (Battarbee 1984, Davis and Anderson 1984, Charles 1985a). Usually, trends in pH curves are not analyzed statis- tically. Instead, subjective interpretations are made that account for the nature of the diatom assemblages, the error associated with the predictive techniques, evidence of sediment mixing, and other factors. This is not a problem if pH changes are great, but relatively small changes, for example, within the standard error of the predictive equation, must be interpreted cautiously, especially if the changes do not show a consistent trend Esterby and El-Shaarawi over several sediment intervals.

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342 8 — J O J CD ~ 111 o Cr I 6 — 11. O in O Oh in IN to I L`J r2 = 0.94 5 — / / ~ ., 4- , ~ / ~ /e ~ / ~ ~ /. / / · , / / / / ~ / ~ · / i' ,- t-~. · ·, 4 5 6 ME aSUR E D p H 7 8 FIGURE 9.2 Predicted lake pH calculated using the equation derived from multiple linear regression of pH categories (assignments based primarily on the distribu- tion of taxa in Adirondack lakes) versus measured surface pH for 37 Adirondack lakes. The dashed lines represent the 95 percent confidence intervals for an individual prediction of pH from diatom data (Charles 1985a). (1981a,b) have developed a point-of-change technique to determine the point of maximum rate of change in a profile of dominant diatom taxa and whether the change is statistically significant. This technique has been used to evaluate taxa profiles from at least one lake (Delorme et al. 1984). The technique has also been applied to pH profiles (G. W. Oehlert, University of Minnesota, personal communication.) New statistical approaches should be developed that account for different sources of uncer tainty (e.g., Oehlert 1984). Diatom and chrysophyte data can be used to address questions such as: Has a lake become more acidic or -

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343 alkaline? How great were the changes? When did they occur? What were the causes? The extent to which these questions can be answered depends on (1) the quality of sediment cores, (2) the preservation and diversity of sediment diatoms, (3) the quality of diatom slide prepara- tion and counting methods, (4) the quality of taxonomic identifications, (5) the precision and accuracy of the pH inference techniques and the applicability of the equa- tions to a study region or lakes, (6) the accuracy and precision of dating and other information on sediment characteristics, and (7) the availability of historical watershed and atmospheric deposition data. Evaluation of Lake Acidification Causes Diatom and chrysophyte data can be used not only to infer the past pH trend of a lake but in many cases to suggest the causes of the changes. There are three major potential causes of acidifica- tion of relatively undisturbed, acid-sensitive lakes in eastern North America: (1) long-term natural acidifi- cation, (2) watershed disturbances, such as logging and fires, and ensuing responses of vegetation and soils, and (3) atmospheric deposition of strong acids from distant sources. Other factors may affect lake pH, but not on a regional scale. These include nearby emission sources, discharge of factory effluent, cultural development (roads and houses, for example), land clearance for agriculture, afforestation (more common in Europe), acid mine drainage, mixing with seawater, liming, paludification, drainage of wetlands, and water-level changes such as those resulting from small man-made dams, beaver activity, or changes in climate. The last factor is probably important only when a significant proportion of a watershed is wetland and net sulfur reduction-oxidation and cation exchange processes are affected. Because these other factors have not, with few exceptions, affected the lakes evaluated in this report they are not considered further. The three primary potential causes of lake acidifica- tion are addressed below. Diatom studies of long-term acidification in both Europe and North America are also briefly reviewed. Following this is a summary of patterns of diatom changes to be expected in response to each major acidification cause.

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344 Long-Term Natural Acidification Long-term trends in the postglacial development of Temperate Zone European and North American lakes have been studied using sediment diatom, pollen, and chemical analyses. These studies indicate that acidic to weakly alkaline lakes in areas having bedrock that is relatively resistant to weathering have undergone a gradual long-term acidification process. This process has been recognized at least since the studies of Lundquist (1924) and has been observed in many geographic areas. In Europe these areas include Sweden (Digerfeldt 1972, 1975, 1977, Renberg 1976, 1978, Renberg and Hellberg 1982, Salomaa and Alhonen 1983, Tolonen 1972), Finland (Alhonen 1967, Tyrni 1972, Tolonen 1967, 1980, Tolonen et al. 1985), Denmark (Nygaard 1956, Foged 196g), northwestern England (Evans 1970, Haworth 1969, Round 1957, 1961, Penning ton 1984), Scotland (Alhonen 1968, Penning ton et al. 1972), Wales (Crabtree 1969, Evans and Walker 1979, Walker 1978), Czechoslovakia (Rehakova 1983), and Greenland (Foged 1972). Fewer regions in North America have been investigated, but diatom data indicate that long-term acidification has occurred in Mirror Lake, New Hampshire (Sherman 1976); Cone Pond, New Hampshire (Ford 1984); Bethany Bog, Connecticut (Patrick 1954); Berry Pond, Massachusetts (Rochester 1978); Heart Lake, Upper Wallface Pond, and Lake Arnold in the Adirondack Mountains, New York (Reed 1982; Whitehead et al. in press; Figure 9.3); Crystal Lake, Wisconsin (Conger 1939); Lake Mary, Wisconsin (J. C. Kingston, University of Minnesota at Duluth, personal communication); Vestaberg Bog, Michigan (Colingsworth et al. 1967); Red Rock Lake, Colorado (Norton and Herrmann 1980); and on Ellesmere Island, above the arctic circle (Smol 1983; J. Smol, Queens University at Kingston, personal communication). We can make some generalizations based on these studies. The magnitude and the rate of long-term acidification vary among lakes and within lakes. Diatom- inferred pH, when it has been calculated, indicates declines from 0.5 pH unit or less to about 2.5 pH units; for example, from pH 7.5 to pH 5.0 for Upper Wallface Pond (Whitehead et al. in press; Figure 9.3). Rates of change are gradual; declines of 1 pH unit take hundreds to thousands of years. In general, lakes with the highest current pH have acidified the least, and data for lakes with pH currently above about 7.5 indicate little

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345 2 m Oh 4 — u, 6 it .$ 1_ 10— 12 · ;~,~ 1 ~ 4, ~ t ¢ ., ~ ) t ', _. / ~ 'odd a. "_ ~ en_ o 0 U. WALLFACE -~ HEART LAKE - - LAKE ARNOLD . . do . -' I~,~ _7~'mp - . 1 4.5 5.5 6.5 7.5 AVERAGE INFERRED pH FIGURE 9.3 Weighted average diatom-inferred pHs for Heart Lake, Upper Wallface Pond, and Lake Arnold, Adirondack Mountains High Peaks Region. Averages were determined from index a, index B. and multiple- regression equations. Each pH value was weighted by the standard error of each predictive equation. B. P. signifies before present. Whitehead et al. in press.

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424 Norton, S. A., and C. T. Hess. 1980. Atmospheric deposition in Norway during the last 300 years as recorded in S.N.S.F. lake sediment. 1. Sediment dating and chemical stratigraphy. Pp. 268-269 of Proceedings of International Conference on the Ecological Impact of Acid Precipitation. Sur Nedb~rs Virkning Pa Skog Og Fisk (SNSF), Sandefjord, Norway. Norton, S. A., and R. F. Wright. 1984. Buffering by sediments during liming and reacidification of two acidified lakes in southern Norway. Paper presented at the Third International Symposium on Interaction between Sediment and Water, Geneva, Switzerland, Aug. 28-31. Norton, S. A., R. F. Dubiel, D. R. Sasseville, and R. B. Davis. 19 7 8 . Paleolimnologic evidence for increased zinc loading in lakes of New England, U.S.A. Verh. Int. Ver. Limnol. 20:538-545. Norton, S. A., C. T. Hess, and R. B. Davis. 1980. Rates of Accumulation of Heavy Metals in Pre- and Post-European Sediments in New England Lakes. Ann Arbor, Mich.: Ann Arbor Science. Norton, S. A., R. B. Davis, and D. F. Brakke. 1981. Responses of northern New England lakes to atmospheric inputs of acids and heavy metals. Completion Report Project A-048-ME. U.S. Department of the Interior. Land and Water Resources Center, University of Maine at Orono, Orono, Me. 90 pp. Norton, S. A., D. W. Hanson, and J. S. Williams. 1982. Modern and paleolimnological evidence for accelerated leaching and metal accumulation in soils in New England, caused by atmospheric deposition. Water Air Soil Pollut. 18:227-239. Norton, S. A., R. B. Davis, and D. S. Anderson. 1985. The distribution and extent of acid and metal precipitation in Northern New England. Final Report. U.S. Fish and Wildlife Service Grant No. 14-16-0009-75-040 . Norton, V. C., and S. J. Herrmann. 1980. Paleolimnology of fresh-water diatoms (Bacillariophyceae) from a sediment core of a Colorado semidrainage mountain lake. Trans. Am. Microscop. Soc. 99:416-425. Nriagu, J. O. 1983. Arsenic enrichment in lakes near the smelters at Sudbury, Ontario. Geochim. Cosmochim. Acta 47:1523-1526. Nriagu, J. O., and H. H. Harvey. 1978. Isotopic variations as an index of sulfur pollution in lakes around Sudbury, Ontario. Nature 273:223-224.

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425 Nriagu, J. O., and H. K. Wong. 1983. Selenium pollution of lakes near the smelters at Sudbury, Ontario. Nature 301:55-57. Nriagu, J. O., A. L. W. Kemp, H. K. T. Wong, and N. Harper. 1979. Sedimentary record of heavy metal pollution in Lake Erie. Geochim. Cosmochim. Acta 43:247-258. Nriagu, J. O., H. K. T. Wong, and R. D. Coker. 1982. Deposition and chemistry of pollutant metals in lakes around the smelters at Sudbury, Ontario. Environ. Sci. Technol. 16:551-560. Nygaard, G. 1956. Ancient and recent flora of diatoms and Chrysophyceae in Lake Gribs¢. Pp. 32-94 of Studies on Humic, Acid Lake Gribs¢, K. Berg and I. C. Peterson, eds. Fol. Limnol. Scand. 8:1-273. Oden, S. 1968. The acidification of air and precipitation and its consequences in the natural environment. Ecology Committee Bull. No. 1, Swedish National Research Council, Stockholm. Oehlert, G. W. 1984. Error bars for paleolimnologically inferred pH histories: a first pass. Technical Report Number 267, Series 2. Department of Statistics, Princeton University, Princeton, N.J. 5 pp. Oldfield, F., R. Thompson, and K. E. Barber. 1978. Changing atmospheric fallout of magnetic particles recorded in recent ombrotrophic peat sections. Science 199:679-680. Oldfield, F., P. G. Appleby, R. S. Cambray, J. D. Eakins, K. E. Barger, R. E. Battarbee, G. R. Pearson, and J. M Williams 1979 210pb 137Cs and 239PU profiles in ombrotrophic peat. Oikos 33:40-45. Oldfield, F., K. Tolonen, and R. Thompson. 1981. History of particulate atmospheric pollution from magnetic measurements in dated Finnish peat profiles. AmbiO 10:185-188. Oliver, B. G., and J. R. M. Kelso. 1983. A role for sediments in retarding the acidification of headwater lakes. Water Air Soil Pollut. 20:379-389. Oliver, B. G., E. M. Thurman, and R. L. Malcolm. 1983. The contribution of humic substances to the acidity of colored natural waters. Geochim. Cosmochim. Acta 47:2031-2035. Olson, E. T. 1983. The distribution and mobility of cesium-137 in Sphagnum bogs of northern North America. M.S. thesis, Department of Physics, University of Maine, Orono, Me. 113 pp.

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426 Ottar, B. 1977. International agreement needed to reduce long-range transport of air pollutants in Europe. Ambio 6:262-269. Ouellet, M., and H. G. Jones. 1983. Paleolimnological evidence for the long-range atmospheric transport of acidic pollutants and heavy metals into the Province of Quebec, eastern Canada. Can. J. Earth Sci. 20:23-36. Pakarinen, P. 1981a. Metal content of ombrotrophic Sphagnum mosses in NW Europe. Ann. Bot. Fenn. 18:281-292. Pakarinen, P. 1981b. Nutrient and trace metal content and retention in reindeer lichen carpets of Finnish ombrotrophic bogs. Ann. Bot. Fenn. 18:265-274. Pakarinen, P., and K. Tolonen. 1976. Regional survey of heavy metals in peat mosses (Sphagnum). Ambio 5:38-40. Pakarinen, P., and K. Tolonen. 1977. Distribution of lead in Sphagnum fuscum profiles in Finland. Oikos 28:69-73. Pakarinen, P., K. Tolonen, and J. Soveri. 1980. Distribution of trace metals and sulfur in the surface peat of Finnish raised bogs. Paper presented at the Sixth International Peat Congress. Duluth, Minnesota, Aug. 17-23. Patrick, R. 1943. The diatoms of Linsley Pond, Connecticut. Proc. Acad. Nat. Sci. Philadelphia 95:53-110. Patrick, R. 1954. The diatom flora of Bethany Bog. J. Protozool. 1:34-37. Patrick, R. 1977. Ecology of freshwater diatoms-diatom communities. Pp. 284-332 of The Biology of Diatoms, D. Werner, ed. Botanical Monographs, Volume 13, Oxford, England: Blackwell Scientific Publications. Patrick, R., and C. W. Reimer. 1966. The Diatoms of the United States. Volume 1. Monogr. Acad. Nat. Sci. Philadelphia. 688 pp. Patrick, R., and C. W. Reimer. 1975. The Diatoms of the United States, Volume 2, Part 1. Monogr. Acad. Nat. Sci. Philadelphia. 213 pp. Patrick, R., V. P. Binetti, and S. G. Halterman. 1981. Acid lakes from natural and anthropogenic causes. Science 211:446-448. Patterson, W. A. 1977. The effect of fire on sedimentation in a small lake in Minnesota. Abstract, p. 211 of Program of the Twentieth Congress of the Society of International Limnologists, Copenhagen. Pennington, W. 1981. Records of a lake's life in time: the sediments. Hydrobiologia 79:197-219.

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427 Pennington, W. 1984. Long-term natural acidification of upland sites. Pp. 28-46 in Cumbria: Evidence from Post-Glacial Lake Sediments. 52nd Annual Report. Freshwater Biological Association, Ambleside, Cumbria, England. Pennington, W., E. Y. Haworth, A. P. Bonny, and J. P. Lishman. 1972. Lake sediments in northern Scotland. Phil. Trans. R. Soc. London Ser. B 264:191-294. Pennington, W. (Mrs. T. G. Tutin), R. S. Cambray, and E. M. Fisher. 1973. Observations on lake sediments using fallout Cs-137 as a tracer. Nature 242:324-326. Reed, S. 1982. The late-glacial and postglacial diatoms of Heart Lake and Upper Wallface Pond in the Adirondack Mountains, New York. M.S. thesis, San Francisco State University, San Francisco, Calif. Rehakova, Z. 1983. Diatom succession in the post-glacial sediments of the Komorany Lake, northwest Bohemia, Czechoslovakia. Hydrobiologia 103:241-245. Renberg, I. 1976. Paleolimnological investigations in Lake Prastsjon. Early Nor Eland 9:113-159. Renberg, I. 1978. Paleolimnology and verve counts of the annually laminated sediment of Lake Rudetjarn, northern Sweden. Early Norrland 11:63-92. Renberg, I., and T. Hellberg. 1982. The pH history of lakes in southwestern Sweden, as calculated from the subfossil diatom flora of the sediments. Ambio 11:30-33. Renberg, I., and M. Wik. 1984. Dating recent lake sediments by soot particle counting. Verh. Int. Ver. Limnol. 22:712-718. Reuther, R., R. F. Wright, and U. Forstner. 1981. Distribution and chemical forms of heavy metals in sediment cores from two Norwegian lakes affected by acid deposition. Pp. 318-321 of Proceedings of the International Conference on Heavy Metals in the Environment. Edinburgh, United Kingdom: CEP Consultants Ltd. Rochester, H. 1978. Late-glacial and postglacial diatom assemblages of Berry Pond, Massachusetts, in relation to watershed ecosystem development. Ph.D. dissertation, Indiana University, Bloomington, Ind. Rosenqvist, I. Th. 1978. Alternative sources for acidification of river water in Norway. Sci. Total Environ. 10:39-49. Round, F. E. 1957. The late-glacial and post-glacial diatom succession in the Kentmere Valley. New Phytol 56:98-126. .

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428 Round, F. E. 1961. The diatoms of a core from Esthwaite Water. New Phytol. 60:43-59. Salomaa, R., and P. Alhonen. 1983. Biostratigraphy of Lake Spitaalijarvi: an ultraoligotrophic small lake in Lauhanvuori, western Finland. Hydrobiologia 103:295-301. Schindler, D. W., R. H. Hesslein, and R. Wagermann. 1980. Effects of acidification on mobilization of heavy metals and radionuclides from the sediments of a freshwater lake. Can. J. Fish. Aquat. Sci. 37:373-377. Schofield, C. L. 1965. Water quality in relation to survival of brook trout, Salvelinus fontinalis (Mitchell). Trans. Am. Fish. Soc. 94:227-235. Schofield, C. L. 1976. Acidification of Adirondack lakes by atmospheric precipitation: extent and magnitude of the problem. Final report, Project F-28-R. New York State Department of Environmental Conservation, Albany, N.Y. Schofield, C. L. lg84. Surface water chemistry in the ILWAS basins. Pp. 6-1--6-32 in The Integrated Lake-Watershed Acidification Study, Vol. 4, R. A. Goldstein and S. A. Gherini, eds. Palo Alto, Calif.: Electric Power Research Institute. Schofield, C. L., and J. N. Galoway. 1977. The utility of paleolimnological analyses of lake sediments for evaluating acid precipitation effects on dilute lakes. Research Project Technical Completion Report. Proj. No. A-071-NY. Office of Water Res. Technol. U.S. Department of the Interior. Sherman, J. W. 1976. Post-pleistocene diatom assemblages in New England lake sediments. Ph.D. dissertation, University of Delaware, Newark, Del. Shiramata, H., R. W. Elias, C. C. Patterson, and M. Koide. 1980. Chronological variations in concentrations and isotopic compositions of anthropogenic atmospheric lead in sediments of a remote subalpine pond. Geocnim. Cosmocnim. Acta 44:149-162. Skei, J., and P. E. Paus. 1979. Surface metal enricument and partitioning of metals in a dated sediment core from a Norwegian fjord. Geochim. Cosmochim. Acta 433:239-246. Smith, R. A. 1872. Air and Rain: The Beginnings of a Chemical Climatology. London: Longmans, Green. Smol, J. P. 1980. Fossil synuracean (Chrysophyceae) scales in lake sediments: a new group of paleoindicators. Can. J. Bot. 58:458-465.

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429 Smol, J. P. 1983. Paleophycology of a high arctic lake near Cape Herschel, Ellesmere Island. Can. J. Bot. 61:2195-2204. Smol, J. P. 198Sa. Chrysophycean microfossils as indicators of lakewater pH. In Diatoms and Lake Acidity, J. P. Smol, R. W. Battarbee, R. B. Davis, and J. Merilainen, eds. The Hague, The Netherlands: W. Junk. Smol, J. P. 1985b. Chrysophycean microfossils in paleolimnological studies. Palaeogeogr. Palaeoclimatol. Palaeoecol. (In press.) Smol, J. P., and M. D. Dickman. 1981. The recent histories of three Canadian Shield lakes: a paleolimnological experiment. Arch. Hydrobiol. 93:83-108. Smol, J. P., D. F. Charles, and D. R. Whitehead. 1984a. Mallomonadacean (Chrysophyceae) assemblages and their relationships with limnological characteristics in 38 Adirondack (New York) lakes. Can. J. Bot. 62:911-923. Smol, J. P., D. F. Charles, and D. R. Whitehead. 1984b. Mallomonadacean microfossils provide evidence of recent lake acidification. Nature 307:628-630. Smol, J. P., R. W. Battarbee, R. B. Davis, and J. Merilainen, eds. 1985. Diatoms and Lake Acidity. The Hague, The Netherlands: W. Junk. (In press.) Somers, K. M., and H. H. Harvey. 1984. Alteration of fish communities in lakes stressed by acid deposition and heavy metals near Wawa, Ontario. Can. J. Fish. Aguat. Sci. 41:20-29. Sreenivasa, M. R., and H. C. Duthie. 1973. The postglacial diatom history of Sunfish Lake, southwestern Ontario. Can. J. Bot. 51:1599-1609. Steinnes, E. 1977. Atmospheric deposition of trace elements in Norway studied by means of moss analysis. Kjeller, Norway: Institute for Atomenergi. 13 pp. and Appendix. Stockner, J. G., and W. W. Benson. 1967. The succession of diatom assemblages in the recent sediments of Lake Washington. Limnol. Oceanogr. 12:513-533. Sweets, P. R. 1983. Differential deposition of diatom frustules in Jellison Hill Pond, Maine. M.S. thesis, University of Maine, Orono, Me. 156 pp. Tan, Y. L., and M. Heit. 1981. Biogenic and abiogenic polynuclear aromatic hydrocarbons in sediments from two remote Adirondack Lakes. Geochim. Cosmochim. Acta 45:2267-2279

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430 Taylor, D. R., M. A. Tompkins, S. E. Kirton, T. Mauney, and D. F. S. Natusch. 1982. Analysis of fly ash produced from combustion of refuse-derived fuel and coal mixtures. Environ. Sci. Technol. 16:148-154. Tolonen, K. 1967. Uber die Entwicklung der Moore in finnischen Nordbarelien. Ann. Bot. Fenn. 4:219-416. Tolonen, K. 1972. On the palaeo-ecology of the Hamptjarn Basin II. Bio- and chemostratigraphy. Early Norrland 1:53-77. Tolonen, K. 1980. Pollen, algal remains, and macrosub- fossils from Lake Galltrask, S. Finland. Ann. Bot. Fenn. 17:394-405. Tolonen, K., and T. Jaakkola. 1983. History of lake acidification and air pollution studied in sediments in South Finland. Ann. Bot. Fenn. 20:57-78. Tolonen, K., and J. Merilainen. 1983. Sedimentary chemistry of a small polluted lake, Galltrask, S. Finland. Hydrobiologia 103:309-318. Tolonen, K., R. B. Davis, and L. S. Widoff. 1984. Peat accumulation rates in selected Maine peatlands. Maine Geological Survey, Department of Conservation. 109 pp. Tolonen, K., M. Liukkonen, R. Harjula, and A. Patila. 1985. Acidification of small lakes in Finland studied by means of sedimentary diatom and chrysophyceae remains. In Diatoms and Lake Acidity, J. P. Smol, R. W. Battarbee, R. B. Davis, and J. Merilainen, eds. The Hague, The Netherlands: W. Junk. Tolonen, K., R. B. Davis, and L. Widoff. Peat accumlation rates in selected Maine peatlands. Maine Geol. Surv. Bull. (In press.) Tynni, R. 1972. The development of Lovojarvi on the basis of its diatoms. Aqua Fenn. 74-82. van Dam, H., and H. Kooyman-van Blokland. 1978. Man-made changes in some Dutch moorland pools, as reflected by historical and recent data about diatoms and macrophytes. Int. Rev. Gesam. Hydrobiol. 63:587-607 van Dam, H., G. Suurmond, and C. J. F. ter Braak. 1981. Impact of acidification on diatoms and chemistry of Dutch moorland pools. Hydrobiologia 83:425-459. Vitt, D. H., and S. Bayley. 1984. The vegetation and water cnemistry of four oligotrophic basin mires in northwestern Ontario. Can. J. Bot. 62:1485-1500. Wakeham, S. G., C. Schaffner, and W. Giger. 1980. Polycyclic aromatic hydrocarbons in recent lake sediments. I. Compounds having anthropogenic or~gins. Geochim. Cosmochim. Acta 44:403-413. .

OCR for page 335
431 Walker, R. 1978. Diatom and pollen studies of a sediment profile from Melynllyn, a mountain tarn in Snowdownia, North Wales. New Phytol. 81:791-804. Watanabe, T., and I. Yasuda. 1982. Diatom assemblages in lacustrine sediments of Lake Shibu-ike, L. Misume-ike, L. Naga-ike, L. Kido-ike in Shiga Highland and a new biotic index based on the diatom assemblage for the acidity of lake water. Jpn. J. Limnol. 43:237-245. Whitehead, D. R., D. F. Charles, S. E. Reed, S. T. Jackson, and M. C. Sheehan. In press. Late-glacial and Holocene acidity changes in Adirondack (N.Y.) lakes. ~ In Diatoms and Lake Acidity, J. P. Smol, R. W. Battarbee, R. B. Davis, and J. Merilainen, eds. Dordrecht, The Netherlands: W. Junk. Wright, H. E., Jr. 1981. The role of fire in land/water interactions. In Fire Regimes and Ecosystem Properties, Pp. 421-444 of Proceedings of a conference held December 11-15, 1978, in Honolulu, Hawaii. General Technical Report W0-26, U.S. Department of Agriculture. Wright, R. F. 1983. Predicting acidification of North American lakes. Report 4/1983, Norwegian Institute for Water Research, Oslo. 165 pp. Wright, R. F. 1984. Changes in the chemistry of Lake Hovvatn, Norway following liming and reacidification. Report 6/1984, Norwegian Institute for Water Research, Oslo. 68 pp. Yan, N. 1983. Effects of changes in pH on transparency and thermal regimes of Lohi lake, near Sudbury, Ontario. Can. J. Fish. Aquat. Sci. 40:621-626.

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APPENDIXES

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