Charles Boylen - Academia.edu (original) (raw)

Papers by Charles Boylen

Research paper thumbnail of Application of multivariate statistics in detecting temporal and spatial patterns of water chemistry in Lake George, New York

Ecological Modelling, 1996

ABSTRACT Cluster and component analyses were used to identify temporal and spatial patterns of wa... more ABSTRACT Cluster and component analyses were used to identify temporal and spatial patterns of water chemistry in Lake George, a meso-oligotrophic lake in northeastern New York, during 1981–1993. The lake includes two major basins that have similar area and volume, but different biological community structure, plankton assemblages, watershed area, and watershed development. Analyses were based on total phosphorus, particulate phosphorus, dissolved organic phosphorus, dissolved inorganic phosphorus, nitrate, calcium, chlorophyll a, silica, chloride, and pH, individually or in combinations. Total phosphorus, chlorophyll a, chloride, and particulate phosphorus were included in the first linear component indicating that these are probably the most important analytes in explaining the total variance of the data. In spring or summer, three or four components explained 86 or 84% of the total variance, respectively. Cluster analysis based on the major components or on the original variables indicated that there are distinct differences in water chemistry between the two major basins of the lake. The only long-term temporal pattern that could be detected by cluster analysis was an increase in chloride concentrations. Cluster analysis is found to be a useful tool to detect both step (abrupt) and monotonic (gradual) changes in time and space.

Research paper thumbnail of Use of Geographic Information Systems to monitor and predict non-native aquatic plant dispersal through north-eastern North America

Hydrobiologia, 2006

North America has a growing problem with invasive aquatic plants. At every level of the aquatic f... more North America has a growing problem with invasive aquatic plants. At every level of the aquatic food web, long-standing checks and balances have become dramatically eroded by the introduction of non-native species. The northeastern United States contains thousands of diverse freshwater habitats, highly heterogeneous in geology and locale, where nuisance aquatic plant growth results in decreased lake water quality, interference with recreational access, degraded flood control structures, and impacts to their aesthetic quality. Early infestation and spread of exotic species is often poorly documented at local and state levels. Consequently, successful management of these species depends on continuous monitoring and definitive identification by both public officials and waterside homeowners. With new mapping capabilities employing software such as Geographic Information Systems (GIS) coupled with the growing computerization of taxonomic records and online availability of regional herbarium records, we have been able to illustrate the temporal and geographic spread of these species, thus enabling aquatic ecologists and managers to make predictions of future infestations. In this paper we evaluate these techniques focusing on three of the most pervasive of exotic aquatic plant species in New York State: Myriophyllum spicatum, Trapa natans and Potamogeton crispus.

Research paper thumbnail of A Hydroacoustic Survey of the Bolton Bay area of Lake George, New York for the Presence of Eurasian Watermilfoil

EXECUTIVE SUMMARY Within the framework of the NYS Milfoil Eradication Grant, the Darrin Fresh Wat... more EXECUTIVE SUMMARY Within the framework of the NYS Milfoil Eradication Grant, the Darrin Fresh Water Institute (DFWI) completed a detailed accounting of the aquatic plant resources found in Bolton Bay, a major embayment to Lake George. Surveys were ...

Research paper thumbnail of Loss of native aquatic plant species in a community dominated by Eurasian watermilfoil

Biology, Ecology and Management of Aquatic Plants, 1999

Ecological evaluation of the impact of an exotic species upon native plant species is frequently ... more Ecological evaluation of the impact of an exotic species upon native plant species is frequently a combination of historical data prior to introduction and after full establishment with little observation in between. The introduction of Myriophyllum spicatum L. (Eurasian watermilfoil) into Lake George, New York, U.S.A. was first noted in 1985.

Research paper thumbnail of Long-term starvation survival of rod and spherical cells of Arthrobacter crystallopoietes

Journal of bacteriology, 1970

Spherical and rod-shaped cells of Arthrobacter crystallopoietes, harvested during exponential gro... more Spherical and rod-shaped cells of Arthrobacter crystallopoietes, harvested during exponential growth, were subjected to total starvation for periods of time as long as 80 days. Viability measurements were made by plate count and slide culture procedures. Both cell forms remained 100% viable for 30 days. Thereafter, viability of rods and spheres decreased equally at a slow rate. After 60 days of starvation, more than 65% of both cell forms were viable. No significant cell lysis occurred as evidenced by microscopic examination, the small amount of 260-nm absorbing material found in the starvation buffer, and stability of radioactively labeled deoxyribonucleic acid in the cells. Endogenous respiration decreased 80-fold during the first 2 days of starvation, accompanied by a 30% decrease in dry weight of the cells. Thereafter, cellular carbon was oxidized to CO(2) at the constant level of 0.03%/hr over the remaining 78-day starvation period.

Research paper thumbnail of Physiological Responses of Anabaena Variabilis (Cyanophyceae) to Instantaneous Exposure to Various Combinations of Light Intensity and Temperature

Research paper thumbnail of Assessment of the Extent to Which Intensively-studied Lakes are Representative of the Adirondack Region and Response to Future Changes in Acidic Deposition

Water, Air, and Soil Pollution, 2007

Research paper thumbnail of The Aquatic Macrophyte Community of Onondaga Lake: Field Survey and Plant Growth Bioassays of Lake Sediments

Lake and Reservoir Management, 1996

The aquatic macrophyte community of Onondaga Lake: Field survey and plant growth bioassays of lak... more The aquatic macrophyte community of Onondaga Lake: Field survey and plant growth bioassays of lake sediments. JD Madsen, JA Bloomfield, JW Sutherland, LW Eichler, CW Boylen Lake and Reservoir Management 12:11, 73-79, 1996. ...

Research paper thumbnail of Physiological Responses of Anabaena Variabilis (Cyanophyceae) to Instantaneous Exposure to Various Combinations of Light Intensity and Temperature

Journal of Phycology, 1982

Research paper thumbnail of Periphyton Dynamics along a Stream with a Gradient of Human Impact

Journal of Freshwater Ecology, 2010

The impact of anthropogenic development on periphytic communities was studied within Finkle Brook... more The impact of anthropogenic development on periphytic communities was studied within Finkle Brook of Bolton Landing, New York. Finkle Brook is located in the Lake George watershed and has increasing anthropogenic development from the headwaters to the mouth. Periphyton was collected and quantified (as algae, bacteria, and fungi) from both natural and artificial substrates during the summer of 2007. On

Research paper thumbnail of Chronic and Episodic Acidification of Adirondack Streams from Acid Rain in 2003–2005

Journal of Environment Quality, 2008

Limited information is available on streams in the Adirondack region of New York, although stream... more Limited information is available on streams in the Adirondack region of New York, although streams are more prone to acidification than the more studied Adirondack lakes. A stream assessment was therefore undertaken in the Oswegatchie and Black River drainages; an area of 4585 km(2) in the western part of the Adirondack region. Acidification was evaluated with the newly developed base-cation surplus (BCS) and the conventional acid-neutralizing capacity by Gran titration (ANC(G)). During the survey when stream water was most acidic (March 2004), 105 of 188 streams (56%) were acidified based on the criterion of BCS < 0 microeq L(-1), whereas 29% were acidified based on an ANC(G) value < 0 microeq L(-1). During the survey when stream water was least acidic (August 2003), 15 of 129 streams (12%) were acidified based on the criterion of BCS < 0 microeq L(-1), whereas 5% were acidified based on ANC(G) value < 0 microeq L(-1). The contribution of acidic deposition to stream acidification was greater than that of strongly acidic organic acids in each of the surveys by factors ranging from approximately 2 to 5, but was greatest during spring snowmelt and least during elevated base flow in August. During snowmelt, the percentage attributable to acidic deposition was 81%, whereas during the October 2003 survey, when dissolved organic carbon (DOC) concentrations were highest, this percentage was 66%. The total length of stream reaches estimated to be prone to acidification was 718 km out of a total of 1237 km of stream reaches that were assessed.

Research paper thumbnail of Physical control of Eurasian watermilfoil in an oligotrophic lake

Hydrobiologia, 1996

The introduction of Eurasian watermilfoil (Myriophyllum spicatum) into oligotrophic waters of hig... more The introduction of Eurasian watermilfoil (Myriophyllum spicatum) into oligotrophic waters of high water clarity in temperate zones of North America has produced growth in excess of 6 m depth and yearly biomass approaching 1000 g m -2 dry weight. From its initial observation in Lake George, New York, USA in 1985, by 1993 milfoil had spread to 106 discrete locations within the lake. A 7-year study of one site having no management showed milfoil to grow expansively, suppressing native plant species from 20 in 1987 to 6 in 1993 with the average number of species m -2 quadrat declining from 5.5 in 1987 to less than 2 in 1993. Management of milfoil by means of hand harvesting, suction harvesting and benthic barrier has reduced the number of unmanaged sites from 106 in 1993 to 11. One year post-treatment at sites utilizing suction harvesting, showed a greater number of native species at all sites than pretreatment with a substantial reduction in milfoil biomass. At sites where benthic barrier was removed 1-2 years after installation, milfoil had recolonized 44% of grid squares within 30 days. Ninety days after barrier removal 74% of grid squares contained milfoil and one year later 71% of the grids supported milfoil. During the first year following mat removal, the average number of species m -2 peaked at 4.7 and stabilized at 4.5 during the second year. Hand harvesting by SCUBA in areas of limited milfoil growth (new sites of infestation and sites of former treatment) was found to reduce the number of milfoil plants present in subsequent years. Hand harvesting did not eliminate milfoil at any of the sites and regrowth/colonization necessitated reharvesting every 3 or more years. Results of evaluations of physical plant management techniques indicate that (1) an integrated program utilizing different techniques based on plant density reduced the growth of milfoil and (2) long term commitment to aquatic plant management is necessary since none of the techniques employed singly were found to eliminate milfoil.

Research paper thumbnail of Photosynthetic characteristics of Myriophyllum spicatum and six submersed aquatic macrophyte species native to Lake George, New York

Freshwater Biology, 1991

1. The macrophyte community of Lake George, New York is diverse, composing of forty-eight submers... more 1. The macrophyte community of Lake George, New York is diverse, composing of forty-eight submersed species representing a wide range of habitats, depth ranges and life-history strategies. The photosynthetic rates of seven representative submersed aquatic macrophytes were determined in laboratory studies using measurements of short-term changes in oxygen concentration at eight light intensities from 0 to 1000 |.imol m~^ s'' at 20°C. The species examined were: Elodea canadensiSy Myriophyllum spicatum., Potamogeton amplifoUus, P. gram-inet4S, P. praelongus, P. robbinsii, and ValUsneria americana.

Research paper thumbnail of Acidification in the Adirondacks: Defining the Biota in Trophic Levels of 30 Chemically Diverse Acid-Impacted Lakes

Environmental Science & Technology, 2010

Research paper thumbnail of Alterations in Aquatic Plant Community Structure following Liming of an Acidic Adirondack Lake

Canadian Journal of Fisheries and Aquatic Sciences, 1994

Research paper thumbnail of Patterns of Epipelic Algal Abundance with Depth, Trophic Status, and Acidity in Poorly Buffered New Hampshire Lakes

Canadian Journal of Fisheries and Aquatic Sciences, 1985

ABSTRACT The biovolume and species composition of algae on sediments in 20 poorly buffered New Ha... more ABSTRACT The biovolume and species composition of algae on sediments in 20 poorly buffered New Hampshire lakes were surveyed in autumn to delineate patterns of community structure and composition with acidity and trophic status of lakes, and along depth gradients within lakes. Patterns of total algal biovolume on sediments were not strongly related to these habitat conditions because of masking by algae that probably settled from the plankton onto sediments. Biovolumes of "benthic" algae generally decreased with depth; however, weak and positive correlations between biovolumes of some benthic algal taxa and depth indicated that benthic algae had adapted to low light conditions and were perhaps facultatively heterotrophic. Decreases in diatom and increases in blue-green algal biovolumes with total phosphorus and chlorophyll a concentrations in lake water indicated that blue-green algae were better adapted for sequestering nutrients in low light environments. The variability in patterns of algal biovolume with acid neutralizing capacity (ANC) and pH indicated that algae had adapted well to different levels of ANC and pH. Biovolumes of blue-greens were negatively correlated with ANC, primarily because of the high biovolumes of various blue-green algae that occurred sporadically in lakes with ANC between 0 and 20 μeg/L and pH between 5.8 and 6.0. Diatom biovolumes generally increased with ANC and pH; however, biovolumes of several species of diatoms, including a Pinnularia, were greatest in low ANC and pH lakes. In general, Eunotia biovolumes decreased and Navicula and Pinnularia biovolumes increased with ANC and pH.

Research paper thumbnail of Littoral zone macrophyte community structure: Distribution and association of species along physical gradients in Lake George, New York, U.S.A

Aquatic Botany, 1987

... were made in the midsummer so that density estimates could be used to approximate midsummer s... more ... were made in the midsummer so that density estimates could be used to approximate midsummer shoot biomass ( Sheldon and Boylen ... Polar coordinate ordination (Bray and Curtis, 1957 ) in conjunction with an iterative technique (Goff and Zedler, 1968) was used to portray ...

Research paper thumbnail of The macrophytic community of an acidic lake in adirondack (New York, U.S.A.): A new depth record for aquatic angiosperms

Aquatic Botany, 1983

Singer, R., Roberts, D.A. and Boylen, C.W., 1983. The macrophytic community of an acidic lake in ... more Singer, R., Roberts, D.A. and Boylen, C.W., 1983. The macrophytic community of an acidic lake in Adirondack (New York, U.S.A.): a new depth record for aquatic angiosperms. Aquat. Bot., 16: 49--57.

Research paper thumbnail of Bacterial Community Structure of Acid-Impacted Lakes: What Controls Diversity?

Applied and Environmental Microbiology, 2008

Although it is recognized that acidification of freshwater systems results in decreased overall s... more Although it is recognized that acidification of freshwater systems results in decreased overall species richness of plants and animals, little is known about the response of aquatic microbial communities to acidification. In this study we examined bacterioplankton community diversity and structure in 18 lakes located in the Adirondack Park (in the state of New York in the United States) that were affected to various degrees by acidic deposition and assessed correlations with 31 physical and chemical parameters. The pH of these lakes ranged from 4.9 to 7.8. These studies were conducted as a component of the Adirondack Effects Assessment Program supported by the U.S. Environmental Protection Agency. Thirty-one independent 16S rRNA gene libraries consisting of 2,135 clones were constructed from epilimnion and hypolimnion water samples. Bacterioplankton community composition was determined by sequencing and amplified ribosomal DNA restriction analysis of the clone libraries. Nineteen bacterial classes representing 95 subclasses were observed, but clone libraries were dominated by representatives of the Actinobacteria and Betaproteobacteria classes. Although the diversity and richness of bacterioplankton communities were positively correlated with pH, the overall community composition assessed by principal component analysis was not. The strongest correlations were observed between bacterioplankton communities and lake depth, hydraulic retention time, dissolved inorganic carbon, and nonlabile monomeric aluminum concentrations. While there was not an overall correlation between bacterioplankton community structure and pH, several bacterial classes, including the Alphaproteobacteria, were directly correlated with acidity. These results indicate that unlike more identifiable correlations between acidity and species richness for higher trophic levels, controls on bacterioplankton community structure are likely more complex, involving both direct and indirect processes.

Research paper thumbnail of Vegetative spread of Eurasian watermilfoil in Lake George, New York

Journal of Aquatic Plant …

Fragment deposition on hydrosoils can provide longer distance dispersal than growth by stolons. F... more Fragment deposition on hydrosoils can provide longer distance dispersal than growth by stolons. Fragment depo- sition on hydrosoils was almost nonexistent in June and July when plants were actively elongating (Figure 3). How- ever, after the period of peak biomass in ...

Research paper thumbnail of Application of multivariate statistics in detecting temporal and spatial patterns of water chemistry in Lake George, New York

Ecological Modelling, 1996

ABSTRACT Cluster and component analyses were used to identify temporal and spatial patterns of wa... more ABSTRACT Cluster and component analyses were used to identify temporal and spatial patterns of water chemistry in Lake George, a meso-oligotrophic lake in northeastern New York, during 1981–1993. The lake includes two major basins that have similar area and volume, but different biological community structure, plankton assemblages, watershed area, and watershed development. Analyses were based on total phosphorus, particulate phosphorus, dissolved organic phosphorus, dissolved inorganic phosphorus, nitrate, calcium, chlorophyll a, silica, chloride, and pH, individually or in combinations. Total phosphorus, chlorophyll a, chloride, and particulate phosphorus were included in the first linear component indicating that these are probably the most important analytes in explaining the total variance of the data. In spring or summer, three or four components explained 86 or 84% of the total variance, respectively. Cluster analysis based on the major components or on the original variables indicated that there are distinct differences in water chemistry between the two major basins of the lake. The only long-term temporal pattern that could be detected by cluster analysis was an increase in chloride concentrations. Cluster analysis is found to be a useful tool to detect both step (abrupt) and monotonic (gradual) changes in time and space.

Research paper thumbnail of Use of Geographic Information Systems to monitor and predict non-native aquatic plant dispersal through north-eastern North America

Hydrobiologia, 2006

North America has a growing problem with invasive aquatic plants. At every level of the aquatic f... more North America has a growing problem with invasive aquatic plants. At every level of the aquatic food web, long-standing checks and balances have become dramatically eroded by the introduction of non-native species. The northeastern United States contains thousands of diverse freshwater habitats, highly heterogeneous in geology and locale, where nuisance aquatic plant growth results in decreased lake water quality, interference with recreational access, degraded flood control structures, and impacts to their aesthetic quality. Early infestation and spread of exotic species is often poorly documented at local and state levels. Consequently, successful management of these species depends on continuous monitoring and definitive identification by both public officials and waterside homeowners. With new mapping capabilities employing software such as Geographic Information Systems (GIS) coupled with the growing computerization of taxonomic records and online availability of regional herbarium records, we have been able to illustrate the temporal and geographic spread of these species, thus enabling aquatic ecologists and managers to make predictions of future infestations. In this paper we evaluate these techniques focusing on three of the most pervasive of exotic aquatic plant species in New York State: Myriophyllum spicatum, Trapa natans and Potamogeton crispus.

Research paper thumbnail of A Hydroacoustic Survey of the Bolton Bay area of Lake George, New York for the Presence of Eurasian Watermilfoil

EXECUTIVE SUMMARY Within the framework of the NYS Milfoil Eradication Grant, the Darrin Fresh Wat... more EXECUTIVE SUMMARY Within the framework of the NYS Milfoil Eradication Grant, the Darrin Fresh Water Institute (DFWI) completed a detailed accounting of the aquatic plant resources found in Bolton Bay, a major embayment to Lake George. Surveys were ...

Research paper thumbnail of Loss of native aquatic plant species in a community dominated by Eurasian watermilfoil

Biology, Ecology and Management of Aquatic Plants, 1999

Ecological evaluation of the impact of an exotic species upon native plant species is frequently ... more Ecological evaluation of the impact of an exotic species upon native plant species is frequently a combination of historical data prior to introduction and after full establishment with little observation in between. The introduction of Myriophyllum spicatum L. (Eurasian watermilfoil) into Lake George, New York, U.S.A. was first noted in 1985.

Research paper thumbnail of Long-term starvation survival of rod and spherical cells of Arthrobacter crystallopoietes

Journal of bacteriology, 1970

Spherical and rod-shaped cells of Arthrobacter crystallopoietes, harvested during exponential gro... more Spherical and rod-shaped cells of Arthrobacter crystallopoietes, harvested during exponential growth, were subjected to total starvation for periods of time as long as 80 days. Viability measurements were made by plate count and slide culture procedures. Both cell forms remained 100% viable for 30 days. Thereafter, viability of rods and spheres decreased equally at a slow rate. After 60 days of starvation, more than 65% of both cell forms were viable. No significant cell lysis occurred as evidenced by microscopic examination, the small amount of 260-nm absorbing material found in the starvation buffer, and stability of radioactively labeled deoxyribonucleic acid in the cells. Endogenous respiration decreased 80-fold during the first 2 days of starvation, accompanied by a 30% decrease in dry weight of the cells. Thereafter, cellular carbon was oxidized to CO(2) at the constant level of 0.03%/hr over the remaining 78-day starvation period.

Research paper thumbnail of Physiological Responses of Anabaena Variabilis (Cyanophyceae) to Instantaneous Exposure to Various Combinations of Light Intensity and Temperature

Research paper thumbnail of Assessment of the Extent to Which Intensively-studied Lakes are Representative of the Adirondack Region and Response to Future Changes in Acidic Deposition

Water, Air, and Soil Pollution, 2007

Research paper thumbnail of The Aquatic Macrophyte Community of Onondaga Lake: Field Survey and Plant Growth Bioassays of Lake Sediments

Lake and Reservoir Management, 1996

The aquatic macrophyte community of Onondaga Lake: Field survey and plant growth bioassays of lak... more The aquatic macrophyte community of Onondaga Lake: Field survey and plant growth bioassays of lake sediments. JD Madsen, JA Bloomfield, JW Sutherland, LW Eichler, CW Boylen Lake and Reservoir Management 12:11, 73-79, 1996. ...

Research paper thumbnail of Physiological Responses of Anabaena Variabilis (Cyanophyceae) to Instantaneous Exposure to Various Combinations of Light Intensity and Temperature

Journal of Phycology, 1982

Research paper thumbnail of Periphyton Dynamics along a Stream with a Gradient of Human Impact

Journal of Freshwater Ecology, 2010

The impact of anthropogenic development on periphytic communities was studied within Finkle Brook... more The impact of anthropogenic development on periphytic communities was studied within Finkle Brook of Bolton Landing, New York. Finkle Brook is located in the Lake George watershed and has increasing anthropogenic development from the headwaters to the mouth. Periphyton was collected and quantified (as algae, bacteria, and fungi) from both natural and artificial substrates during the summer of 2007. On

Research paper thumbnail of Chronic and Episodic Acidification of Adirondack Streams from Acid Rain in 2003–2005

Journal of Environment Quality, 2008

Limited information is available on streams in the Adirondack region of New York, although stream... more Limited information is available on streams in the Adirondack region of New York, although streams are more prone to acidification than the more studied Adirondack lakes. A stream assessment was therefore undertaken in the Oswegatchie and Black River drainages; an area of 4585 km(2) in the western part of the Adirondack region. Acidification was evaluated with the newly developed base-cation surplus (BCS) and the conventional acid-neutralizing capacity by Gran titration (ANC(G)). During the survey when stream water was most acidic (March 2004), 105 of 188 streams (56%) were acidified based on the criterion of BCS < 0 microeq L(-1), whereas 29% were acidified based on an ANC(G) value < 0 microeq L(-1). During the survey when stream water was least acidic (August 2003), 15 of 129 streams (12%) were acidified based on the criterion of BCS < 0 microeq L(-1), whereas 5% were acidified based on ANC(G) value < 0 microeq L(-1). The contribution of acidic deposition to stream acidification was greater than that of strongly acidic organic acids in each of the surveys by factors ranging from approximately 2 to 5, but was greatest during spring snowmelt and least during elevated base flow in August. During snowmelt, the percentage attributable to acidic deposition was 81%, whereas during the October 2003 survey, when dissolved organic carbon (DOC) concentrations were highest, this percentage was 66%. The total length of stream reaches estimated to be prone to acidification was 718 km out of a total of 1237 km of stream reaches that were assessed.

Research paper thumbnail of Physical control of Eurasian watermilfoil in an oligotrophic lake

Hydrobiologia, 1996

The introduction of Eurasian watermilfoil (Myriophyllum spicatum) into oligotrophic waters of hig... more The introduction of Eurasian watermilfoil (Myriophyllum spicatum) into oligotrophic waters of high water clarity in temperate zones of North America has produced growth in excess of 6 m depth and yearly biomass approaching 1000 g m -2 dry weight. From its initial observation in Lake George, New York, USA in 1985, by 1993 milfoil had spread to 106 discrete locations within the lake. A 7-year study of one site having no management showed milfoil to grow expansively, suppressing native plant species from 20 in 1987 to 6 in 1993 with the average number of species m -2 quadrat declining from 5.5 in 1987 to less than 2 in 1993. Management of milfoil by means of hand harvesting, suction harvesting and benthic barrier has reduced the number of unmanaged sites from 106 in 1993 to 11. One year post-treatment at sites utilizing suction harvesting, showed a greater number of native species at all sites than pretreatment with a substantial reduction in milfoil biomass. At sites where benthic barrier was removed 1-2 years after installation, milfoil had recolonized 44% of grid squares within 30 days. Ninety days after barrier removal 74% of grid squares contained milfoil and one year later 71% of the grids supported milfoil. During the first year following mat removal, the average number of species m -2 peaked at 4.7 and stabilized at 4.5 during the second year. Hand harvesting by SCUBA in areas of limited milfoil growth (new sites of infestation and sites of former treatment) was found to reduce the number of milfoil plants present in subsequent years. Hand harvesting did not eliminate milfoil at any of the sites and regrowth/colonization necessitated reharvesting every 3 or more years. Results of evaluations of physical plant management techniques indicate that (1) an integrated program utilizing different techniques based on plant density reduced the growth of milfoil and (2) long term commitment to aquatic plant management is necessary since none of the techniques employed singly were found to eliminate milfoil.

Research paper thumbnail of Photosynthetic characteristics of Myriophyllum spicatum and six submersed aquatic macrophyte species native to Lake George, New York

Freshwater Biology, 1991

1. The macrophyte community of Lake George, New York is diverse, composing of forty-eight submers... more 1. The macrophyte community of Lake George, New York is diverse, composing of forty-eight submersed species representing a wide range of habitats, depth ranges and life-history strategies. The photosynthetic rates of seven representative submersed aquatic macrophytes were determined in laboratory studies using measurements of short-term changes in oxygen concentration at eight light intensities from 0 to 1000 |.imol m~^ s'' at 20°C. The species examined were: Elodea canadensiSy Myriophyllum spicatum., Potamogeton amplifoUus, P. gram-inet4S, P. praelongus, P. robbinsii, and ValUsneria americana.

Research paper thumbnail of Acidification in the Adirondacks: Defining the Biota in Trophic Levels of 30 Chemically Diverse Acid-Impacted Lakes

Environmental Science & Technology, 2010

Research paper thumbnail of Alterations in Aquatic Plant Community Structure following Liming of an Acidic Adirondack Lake

Canadian Journal of Fisheries and Aquatic Sciences, 1994

Research paper thumbnail of Patterns of Epipelic Algal Abundance with Depth, Trophic Status, and Acidity in Poorly Buffered New Hampshire Lakes

Canadian Journal of Fisheries and Aquatic Sciences, 1985

ABSTRACT The biovolume and species composition of algae on sediments in 20 poorly buffered New Ha... more ABSTRACT The biovolume and species composition of algae on sediments in 20 poorly buffered New Hampshire lakes were surveyed in autumn to delineate patterns of community structure and composition with acidity and trophic status of lakes, and along depth gradients within lakes. Patterns of total algal biovolume on sediments were not strongly related to these habitat conditions because of masking by algae that probably settled from the plankton onto sediments. Biovolumes of "benthic" algae generally decreased with depth; however, weak and positive correlations between biovolumes of some benthic algal taxa and depth indicated that benthic algae had adapted to low light conditions and were perhaps facultatively heterotrophic. Decreases in diatom and increases in blue-green algal biovolumes with total phosphorus and chlorophyll a concentrations in lake water indicated that blue-green algae were better adapted for sequestering nutrients in low light environments. The variability in patterns of algal biovolume with acid neutralizing capacity (ANC) and pH indicated that algae had adapted well to different levels of ANC and pH. Biovolumes of blue-greens were negatively correlated with ANC, primarily because of the high biovolumes of various blue-green algae that occurred sporadically in lakes with ANC between 0 and 20 μeg/L and pH between 5.8 and 6.0. Diatom biovolumes generally increased with ANC and pH; however, biovolumes of several species of diatoms, including a Pinnularia, were greatest in low ANC and pH lakes. In general, Eunotia biovolumes decreased and Navicula and Pinnularia biovolumes increased with ANC and pH.

Research paper thumbnail of Littoral zone macrophyte community structure: Distribution and association of species along physical gradients in Lake George, New York, U.S.A

Aquatic Botany, 1987

... were made in the midsummer so that density estimates could be used to approximate midsummer s... more ... were made in the midsummer so that density estimates could be used to approximate midsummer shoot biomass ( Sheldon and Boylen ... Polar coordinate ordination (Bray and Curtis, 1957 ) in conjunction with an iterative technique (Goff and Zedler, 1968) was used to portray ...

Research paper thumbnail of The macrophytic community of an acidic lake in adirondack (New York, U.S.A.): A new depth record for aquatic angiosperms

Aquatic Botany, 1983

Singer, R., Roberts, D.A. and Boylen, C.W., 1983. The macrophytic community of an acidic lake in ... more Singer, R., Roberts, D.A. and Boylen, C.W., 1983. The macrophytic community of an acidic lake in Adirondack (New York, U.S.A.): a new depth record for aquatic angiosperms. Aquat. Bot., 16: 49--57.

Research paper thumbnail of Bacterial Community Structure of Acid-Impacted Lakes: What Controls Diversity?

Applied and Environmental Microbiology, 2008

Although it is recognized that acidification of freshwater systems results in decreased overall s... more Although it is recognized that acidification of freshwater systems results in decreased overall species richness of plants and animals, little is known about the response of aquatic microbial communities to acidification. In this study we examined bacterioplankton community diversity and structure in 18 lakes located in the Adirondack Park (in the state of New York in the United States) that were affected to various degrees by acidic deposition and assessed correlations with 31 physical and chemical parameters. The pH of these lakes ranged from 4.9 to 7.8. These studies were conducted as a component of the Adirondack Effects Assessment Program supported by the U.S. Environmental Protection Agency. Thirty-one independent 16S rRNA gene libraries consisting of 2,135 clones were constructed from epilimnion and hypolimnion water samples. Bacterioplankton community composition was determined by sequencing and amplified ribosomal DNA restriction analysis of the clone libraries. Nineteen bacterial classes representing 95 subclasses were observed, but clone libraries were dominated by representatives of the Actinobacteria and Betaproteobacteria classes. Although the diversity and richness of bacterioplankton communities were positively correlated with pH, the overall community composition assessed by principal component analysis was not. The strongest correlations were observed between bacterioplankton communities and lake depth, hydraulic retention time, dissolved inorganic carbon, and nonlabile monomeric aluminum concentrations. While there was not an overall correlation between bacterioplankton community structure and pH, several bacterial classes, including the Alphaproteobacteria, were directly correlated with acidity. These results indicate that unlike more identifiable correlations between acidity and species richness for higher trophic levels, controls on bacterioplankton community structure are likely more complex, involving both direct and indirect processes.

Research paper thumbnail of Vegetative spread of Eurasian watermilfoil in Lake George, New York

Journal of Aquatic Plant …

Fragment deposition on hydrosoils can provide longer distance dispersal than growth by stolons. F... more Fragment deposition on hydrosoils can provide longer distance dispersal than growth by stolons. Fragment depo- sition on hydrosoils was almost nonexistent in June and July when plants were actively elongating (Figure 3). How- ever, after the period of peak biomass in ...