A study of aquatic vegetation of 31 small, dilute, and unproductive lakes in the Adirondack Mount... more A study of aquatic vegetation of 31 small, dilute, and unproductive lakes in the Adirondack Mountains of New York shows that macrophyte species composition is primarily related to variation in pH and associated factors. Among the lakes, surface water pH ranged from 4.5 to 7.8; conductivity ranged from 11.9 to 58.7 μS/cm. Relationships between aquatic vegetation and environmental factors were studied using detrended correspondence analysis (DCA). Submersed and floating-leaved taxa were analyzed separately from emergent taxa. Correlations between DCA axis 1 and pH-related factors (pH, alkalinity, Ca, Mg, Na, Al, conductivity, elevation) were strong for both submersed plus floating-leaved and emergent taxa. No significant correlations were found with water color, transparency, or trophic status indicators (total P and chlorophyll a). Between-lake variation in composition of aquatic vegetation in Adirondack lakes follows a pH "complex-gradient." Influences of elevation, morphometry, and substrate are secondary. Our results indicate that acidification of softwater lakes could be accompanied by significant changes in aquatic macrophyte assemblages.
... 5. Charles, DF, DR Whitehead, DR Engstrom, BD Fry, RA Hires, SA Norton, JS Owen, LA Roll, SC ... more ... 5. Charles, DF, DR Whitehead, DR Engstrom, BD Fry, RA Hires, SA Norton, JS Owen, LA Roll, SC Schindler, JP Smol, AJ Uutala, JR White & RJ Wise, 1987. Paleolimnological evidence for recent acidification of Big Moose Lake, Adirondack Mountains, NY (USA). ...
Nature is the international weekly journal of science: a magazine style journal that publishes fu... more Nature is the international weekly journal of science: a magazine style journal that publishes full-length research papers in all disciplines of science, as well as News and Views, reviews, news, features, commentaries, web focuses and more, covering all branches of science and ...
ABSTRACT We used sediment diatoms to infer historical changes in total phosphorus (TP) concentrat... more ABSTRACT We used sediment diatoms to infer historical changes in total phosphorus (TP) concentration in 26 New York and New Jersey (USA) lakes using a top–bottom approach (i.e., the top of the core represents present conditions and the bottom represents past conditions). Detailed stratigraphic analyses were performed on cores from Greenwood (New Jersey and New York) and Cossayuna lakes (New York). TP reconstructions were performed using 2 weighted-averaging partial-least-squares (WA-PLS) transfer functions: (1) an interregional 278-lake calibration set from northeastern United States (NE-US model: r2boot = 0.69, root mean square error of prediction RMSEP) = 1.8 μg/L); and (2) a regional 33-lake (callibration set from New Jersey and New York (NJ-NY model: r2boot = 0.54, RMSEP = 1.5 μg/L). The NJ-NY model provided better estimates for modern TP but failed to provide reliable estimates for low TP values and reliable modern analogs for half of the bottom samples. Low TP concentrations were better inferred by the NE-US model, which included a higher number of oligotrophic lakes. Average change for all lakes was an increase of 2 to 7 μg/L TP. Greenwood and Cossayuna lakes inferred TP concentrations have increased up to 21 μg/L, presumably as a result of post-settlement anthropogenic activities. The inferred TP temporal changes provide important insight on the magnitude of cultural eutrophication. The use of 2 different inference models demonstrates the advantage of using a regional versus a larger-scale inference model in estimating the degree of change in historical lake TP. Careful interpretation of TP reconstructions can be used to provide reliable estimates of cost-effective targets for lake restoration programs.
ABSTRACT We analyzed nutrient data from the National Lakes Assessment (NLA), a probability survey... more ABSTRACT We analyzed nutrient data from the National Lakes Assessment (NLA), a probability survey of 1028 lakes >4 ha in lake area across the conterminous USA to quantify and contrast different methods of setting nutrient criteria. We calculated potential nutrient criteria for total P (TP), total N (TN), and chlorophyll a (Chl a) by 4 methods (25th percentile of population, 75th percentile of least-disturbed reference sites, diatom-based paleolimnological reconstruction, and stressor modeling) and compared them to existing draft US Environmental Protection Agency (EPA) criteria within national nutrient ecoregions. At the national scale, the ecoregional criteria derived from the different approaches were highly correlated. However, absolute values differed widely among approaches within ecoregions. Population 25th percentiles were lower (often by a factor of 2–6) than values obtained with other approaches in almost all ecoregions, results indicating that population 25th percentiles cannot be used as a surrogate for reference-site or paleolimnological approaches. Stressor regression models often did not explain much of the variance in nutrient concentration, especially in the less-disturbed ecoregions. For TP, diatom-inferred paleolimnological criteria were higher than reference-site-based criteria, which were higher than stressor-model criteria. For TN, these 3 approaches were very comparable. For Chl a, the reference-site and stressor-model approaches gave similar criterion values in low-nutrient ecoregions, but the reference-site 75th-percentile approach had much higher criterion values than the stressor-modeling approach in the high-nutrient ecoregions. Use of NLA reference-site 75th percentiles as nutrient criteria showed that 42% of the assessed lakes exceeded TP criteria, 47% exceeded TN criteria, and 32% exceeded Chl a criteria. Survey results also suggest that most lakes are P limited. Ninety-three percent of the lakes in the population had molar TN∶TP ratios > 16, and 52% had TN∶TP > 50.
... In the Sierras they are Robert Holmes and Mark Whiting (funded by the Califor-nia Air Resourc... more ... In the Sierras they are Robert Holmes and Mark Whiting (funded by the Califor-nia Air Resources Board), and Mark Whiting, Donald Whitehead, and Donald Charles (funded by Southern California Edison). ... PROJECT COORDINATORS Donald Whitehead Donald Charles ...
Philosophical transactions of the Royal Society of London, Mar 12, 1990
A model of long term acidification (magic) is applied to a range of catchments in Scotland that a... more A model of long term acidification (magic) is applied to a range of catchments in Scotland that are subject to different pollution inputs and land uses. The simulated historical trends in pH are compared with data from palaeolimnological reconstructions undertaken at the same sites. Both techniques produce similar historical acidification trends and, with some exceptions, closely match observed present day pH. The magic model results indicate that pollution inputs and land-use, particularly afforestation, have significant effects on surface water acidification. Moreover, the model indicates that reversibility may be occurring at several sites. Reversibility of acidification is further explored by using the model in predictive mode under several scenarios for reduction deposition.
The siliceous scales of 30 mallomonadacean taxa were identified and counted from the surficial se... more The siliceous scales of 30 mallomonadacean taxa were identified and counted from the surficial sediments of 38 Adirondack lakes. The scales were usually abundant and were always well preserved. The Adirondack flora is typical of acidic to circumneutral oligotrophic lakes. Common taxa include Mallomonas acaroides, M. caudata, M. crassisquama, M. hamata, M. pseudocoronata, M. punctifera, Synura echinulata, S. petersenii, S. sphagnicola, S. spinosa, and Chrysosphaerella longispina. The abundance of certain species (e.g., Mallomonas hindonii, M. hamata) appears to be a reliable indication of acidic waters. Reciprocal averaging (RA) ordination was used to determine if distribution of the mallomonadacean assemblages corresponded with major environmental gradients. Correlations between the first RA axis scores and lakewater pH (r2 = 0.63) and related factors (log10 alkalinity, r2 = 0.66; pCa, r2 = 0.39; pMg, r2 = 0.43) were strongest. Relationships were weaker with average depth, summer epilimnion temperature, elevation, NO3, and total Al, and were not statistically significant with conductivity, color, Secchi disc transparency, total P, chlorophyll a, SO4, and Si. Cluster analysis grouped both lakes and taxa into categories best explained by their pH-related characteristics. Analysis of surficial sediment from lakes with known limnological characteristics is a useful approach for the study of the ecology and taxonomy of the Mallomonadaceae. Our data demonstrate that mallomonadacean distributions reflect lake conditions and, therefore, are potentially useful indicators in limnological and paleolimnological studies.
ABSTRACT Paleoecological analysis of the sediment record of 12 Adirondack lakes reveals that the ... more ABSTRACT Paleoecological analysis of the sediment record of 12 Adirondack lakes reveals that the 8 clearwater lakes with current pH -1 have acidified recently. The onset of this acidification occurred between 1920 and 1970. Loss of alkalinity, based on quanitative analysis of diatom assemblages, ranged from 2 to 35 µeq l-1. The acidification trends are substantiated by several lines of evidence including stratigraphies of diatom, chrysophyte, chironomid, and cladoceran remains, Ca:Ti and Mn:Ti ratios, sequentially extracted forms of Al, and historical fish data. Acidification trends appear to be continuing in some lakes, despite reductions in atmospheric sulfur loading that began in the early 1970s. The primary cause of the acidification trend is clearly increased atmospheric deposition of strong acids derived from the combustion of fossil fuels. Natural processes and watershed disturbances cannot account for the changes in water chemistry that have occurred, but they may play a role. Sediment core profiles of Pb, Cu, V, Zn, S, polycyclic aromatic hydrocarbons, magnetic particles, and coal and oil soot provide a clear record of increased atmospheric input of materials associated with the combustion of fossil fuels beginning in the late 1800s and early 1900s. The primary evidence for acidification occurs after that period, and the pattern of water chemistry response to increased acid inputs is consistent with current understanding of lake-watershed acidification processes.
Paleoecological analyses of sediments from nine northern Great Lakes states (NGLS) lakes reveal s... more Paleoecological analyses of sediments from nine northern Great Lakes states (NGLS) lakes reveal small pH changes in seven of these lakes since 1860, four of these being declines. The largest diatom-inferred (DI) pH declines of 0.5 pH units were found in Brown L. and Denton L., Wisconsin. Two other lakes with suspected total alkalinity declines (based on an acidification model
A study of aquatic vegetation of 31 small, dilute, and unproductive lakes in the Adirondack Mount... more A study of aquatic vegetation of 31 small, dilute, and unproductive lakes in the Adirondack Mountains of New York shows that macrophyte species composition is primarily related to variation in pH and associated factors. Among the lakes, surface water pH ranged from 4.5 to 7.8; conductivity ranged from 11.9 to 58.7 μS/cm. Relationships between aquatic vegetation and environmental factors were studied using detrended correspondence analysis (DCA). Submersed and floating-leaved taxa were analyzed separately from emergent taxa. Correlations between DCA axis 1 and pH-related factors (pH, alkalinity, Ca, Mg, Na, Al, conductivity, elevation) were strong for both submersed plus floating-leaved and emergent taxa. No significant correlations were found with water color, transparency, or trophic status indicators (total P and chlorophyll a). Between-lake variation in composition of aquatic vegetation in Adirondack lakes follows a pH "complex-gradient." Influences of elevation, morphometry, and substrate are secondary. Our results indicate that acidification of softwater lakes could be accompanied by significant changes in aquatic macrophyte assemblages.
... 5. Charles, DF, DR Whitehead, DR Engstrom, BD Fry, RA Hires, SA Norton, JS Owen, LA Roll, SC ... more ... 5. Charles, DF, DR Whitehead, DR Engstrom, BD Fry, RA Hires, SA Norton, JS Owen, LA Roll, SC Schindler, JP Smol, AJ Uutala, JR White & RJ Wise, 1987. Paleolimnological evidence for recent acidification of Big Moose Lake, Adirondack Mountains, NY (USA). ...
Nature is the international weekly journal of science: a magazine style journal that publishes fu... more Nature is the international weekly journal of science: a magazine style journal that publishes full-length research papers in all disciplines of science, as well as News and Views, reviews, news, features, commentaries, web focuses and more, covering all branches of science and ...
ABSTRACT We used sediment diatoms to infer historical changes in total phosphorus (TP) concentrat... more ABSTRACT We used sediment diatoms to infer historical changes in total phosphorus (TP) concentration in 26 New York and New Jersey (USA) lakes using a top–bottom approach (i.e., the top of the core represents present conditions and the bottom represents past conditions). Detailed stratigraphic analyses were performed on cores from Greenwood (New Jersey and New York) and Cossayuna lakes (New York). TP reconstructions were performed using 2 weighted-averaging partial-least-squares (WA-PLS) transfer functions: (1) an interregional 278-lake calibration set from northeastern United States (NE-US model: r2boot = 0.69, root mean square error of prediction RMSEP) = 1.8 μg/L); and (2) a regional 33-lake (callibration set from New Jersey and New York (NJ-NY model: r2boot = 0.54, RMSEP = 1.5 μg/L). The NJ-NY model provided better estimates for modern TP but failed to provide reliable estimates for low TP values and reliable modern analogs for half of the bottom samples. Low TP concentrations were better inferred by the NE-US model, which included a higher number of oligotrophic lakes. Average change for all lakes was an increase of 2 to 7 μg/L TP. Greenwood and Cossayuna lakes inferred TP concentrations have increased up to 21 μg/L, presumably as a result of post-settlement anthropogenic activities. The inferred TP temporal changes provide important insight on the magnitude of cultural eutrophication. The use of 2 different inference models demonstrates the advantage of using a regional versus a larger-scale inference model in estimating the degree of change in historical lake TP. Careful interpretation of TP reconstructions can be used to provide reliable estimates of cost-effective targets for lake restoration programs.
ABSTRACT We analyzed nutrient data from the National Lakes Assessment (NLA), a probability survey... more ABSTRACT We analyzed nutrient data from the National Lakes Assessment (NLA), a probability survey of 1028 lakes >4 ha in lake area across the conterminous USA to quantify and contrast different methods of setting nutrient criteria. We calculated potential nutrient criteria for total P (TP), total N (TN), and chlorophyll a (Chl a) by 4 methods (25th percentile of population, 75th percentile of least-disturbed reference sites, diatom-based paleolimnological reconstruction, and stressor modeling) and compared them to existing draft US Environmental Protection Agency (EPA) criteria within national nutrient ecoregions. At the national scale, the ecoregional criteria derived from the different approaches were highly correlated. However, absolute values differed widely among approaches within ecoregions. Population 25th percentiles were lower (often by a factor of 2–6) than values obtained with other approaches in almost all ecoregions, results indicating that population 25th percentiles cannot be used as a surrogate for reference-site or paleolimnological approaches. Stressor regression models often did not explain much of the variance in nutrient concentration, especially in the less-disturbed ecoregions. For TP, diatom-inferred paleolimnological criteria were higher than reference-site-based criteria, which were higher than stressor-model criteria. For TN, these 3 approaches were very comparable. For Chl a, the reference-site and stressor-model approaches gave similar criterion values in low-nutrient ecoregions, but the reference-site 75th-percentile approach had much higher criterion values than the stressor-modeling approach in the high-nutrient ecoregions. Use of NLA reference-site 75th percentiles as nutrient criteria showed that 42% of the assessed lakes exceeded TP criteria, 47% exceeded TN criteria, and 32% exceeded Chl a criteria. Survey results also suggest that most lakes are P limited. Ninety-three percent of the lakes in the population had molar TN∶TP ratios > 16, and 52% had TN∶TP > 50.
... In the Sierras they are Robert Holmes and Mark Whiting (funded by the Califor-nia Air Resourc... more ... In the Sierras they are Robert Holmes and Mark Whiting (funded by the Califor-nia Air Resources Board), and Mark Whiting, Donald Whitehead, and Donald Charles (funded by Southern California Edison). ... PROJECT COORDINATORS Donald Whitehead Donald Charles ...
Philosophical transactions of the Royal Society of London, Mar 12, 1990
A model of long term acidification (magic) is applied to a range of catchments in Scotland that a... more A model of long term acidification (magic) is applied to a range of catchments in Scotland that are subject to different pollution inputs and land uses. The simulated historical trends in pH are compared with data from palaeolimnological reconstructions undertaken at the same sites. Both techniques produce similar historical acidification trends and, with some exceptions, closely match observed present day pH. The magic model results indicate that pollution inputs and land-use, particularly afforestation, have significant effects on surface water acidification. Moreover, the model indicates that reversibility may be occurring at several sites. Reversibility of acidification is further explored by using the model in predictive mode under several scenarios for reduction deposition.
The siliceous scales of 30 mallomonadacean taxa were identified and counted from the surficial se... more The siliceous scales of 30 mallomonadacean taxa were identified and counted from the surficial sediments of 38 Adirondack lakes. The scales were usually abundant and were always well preserved. The Adirondack flora is typical of acidic to circumneutral oligotrophic lakes. Common taxa include Mallomonas acaroides, M. caudata, M. crassisquama, M. hamata, M. pseudocoronata, M. punctifera, Synura echinulata, S. petersenii, S. sphagnicola, S. spinosa, and Chrysosphaerella longispina. The abundance of certain species (e.g., Mallomonas hindonii, M. hamata) appears to be a reliable indication of acidic waters. Reciprocal averaging (RA) ordination was used to determine if distribution of the mallomonadacean assemblages corresponded with major environmental gradients. Correlations between the first RA axis scores and lakewater pH (r2 = 0.63) and related factors (log10 alkalinity, r2 = 0.66; pCa, r2 = 0.39; pMg, r2 = 0.43) were strongest. Relationships were weaker with average depth, summer epilimnion temperature, elevation, NO3, and total Al, and were not statistically significant with conductivity, color, Secchi disc transparency, total P, chlorophyll a, SO4, and Si. Cluster analysis grouped both lakes and taxa into categories best explained by their pH-related characteristics. Analysis of surficial sediment from lakes with known limnological characteristics is a useful approach for the study of the ecology and taxonomy of the Mallomonadaceae. Our data demonstrate that mallomonadacean distributions reflect lake conditions and, therefore, are potentially useful indicators in limnological and paleolimnological studies.
ABSTRACT Paleoecological analysis of the sediment record of 12 Adirondack lakes reveals that the ... more ABSTRACT Paleoecological analysis of the sediment record of 12 Adirondack lakes reveals that the 8 clearwater lakes with current pH -1 have acidified recently. The onset of this acidification occurred between 1920 and 1970. Loss of alkalinity, based on quanitative analysis of diatom assemblages, ranged from 2 to 35 µeq l-1. The acidification trends are substantiated by several lines of evidence including stratigraphies of diatom, chrysophyte, chironomid, and cladoceran remains, Ca:Ti and Mn:Ti ratios, sequentially extracted forms of Al, and historical fish data. Acidification trends appear to be continuing in some lakes, despite reductions in atmospheric sulfur loading that began in the early 1970s. The primary cause of the acidification trend is clearly increased atmospheric deposition of strong acids derived from the combustion of fossil fuels. Natural processes and watershed disturbances cannot account for the changes in water chemistry that have occurred, but they may play a role. Sediment core profiles of Pb, Cu, V, Zn, S, polycyclic aromatic hydrocarbons, magnetic particles, and coal and oil soot provide a clear record of increased atmospheric input of materials associated with the combustion of fossil fuels beginning in the late 1800s and early 1900s. The primary evidence for acidification occurs after that period, and the pattern of water chemistry response to increased acid inputs is consistent with current understanding of lake-watershed acidification processes.
Paleoecological analyses of sediments from nine northern Great Lakes states (NGLS) lakes reveal s... more Paleoecological analyses of sediments from nine northern Great Lakes states (NGLS) lakes reveal small pH changes in seven of these lakes since 1860, four of these being declines. The largest diatom-inferred (DI) pH declines of 0.5 pH units were found in Brown L. and Denton L., Wisconsin. Two other lakes with suspected total alkalinity declines (based on an acidification model
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