Gregory B Lawrence (Former Employee)
Science and Products
Filter Total Items: 108
Regional growth decline of sugar maple (Acer saccharum) and its potential causes
Sugar maple (Acer saccharum Marsh) has experienced poor vigor, regeneration failure, and elevated mortality across much of its range, but there has been relatively little attention to its growth rates. Based on a well-replicated dendrochronological network of range-centered populations in the Adirondack Mountains (USA), which encompassed a wide gradient of soil fertility, we observed that the majo
Authors
Daniel A. Bishop, Colin M. Beier, Neil Pederson, Gregory B. Lawrence, John C Stella, Timothy J. Sullivan
Photosynthetic and growth response of sugar maple (Acer saccharum Marsh.) mature trees and seedlings to calcium, magnesium, and nitrogen additions in the Catskill Mountains, NY, USA
Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arr
Authors
Bahram Momen, Shawna J Behling, Gregory B. Lawrence, Joseph H Sullivan
Declining acidic deposition begins reversal of forest-soil acidification in the northeastern U.S. and eastern Canada
Decreasing trends in acidic deposition levels over the past several decades have led to partial chemical recovery of surface waters. However, depletion of soil Ca from acidic deposition has slowed surface water recovery and led to the impairment of both aquatic and terrestrial ecosystems. Nevertheless, documentation of acidic deposition effects on soils has been limited, and little is known regard
Authors
Gregory B. Lawrence, Paul W. Hazlett, Ivan J. Fernandez, Rock Ouimet, Scott W. Bailey, Walter C. Shortle, Kevin T. Smith, Michael R. Antidormi
Coastal plain pond water quality and mercury contend of biota of the Long Island Central Pine Barrens and Mashomack Preserve: Effects of atmospheric deposition and human development
Pine barrens are considered an imperiled ecosystem in the northeastern U.S. The Suffolk County Pine Barrens, once the second largest in the Northeast, were substantially reduced and fragmented by development during the 20th century. The coastal plain ponds being considered in this study occur in central Suffolk County within the Long Island Central Pine Barrens region. This highly unique natural e
Authors
Gregory B. Lawrence, Jason Siemion, Oksana P. Lane
Inter-laboratory variation in the chemical analysis of acidic forest soil reference samples from eastern North America
Long-term forest soil monitoring and research often requires a comparison of laboratory data generated at different times and in different laboratories. Quantifying the uncertainty associated with these analyses is necessary to assess temporal changes in soil properties. Forest soil chemical properties, and methods to measure these properties, often differ from agronomic and horticultural soils. S
Authors
Donald S. Ross, Scott W Bailiey, Russell D Briggs, Johanna Curry, Ivan J. Fernandez, Guinevere Fredriksen, Christine L. Goodale, Paul W. Hazlett, Paul R Heine, Chris E. Johnson, John T Larson, Gregory B. Lawrence, Randy K Kolka, Rock Ouimet, D Pare, Daniel D. Richter, Charles D Shirmer, Richard A.F. Warby
Acidic deposition along the Appalachian Trail corridor and its effects on acid-sensitive terrestrial and aquatic resources
The Appalachian National Scenic Trail (AT), a unit of the National Park Service (NPS), spans nearly 2,200 miles from Georgia to Maine, encompassing a diverse range of ecosystems. Acidic deposition (acid rain) threatens the AT’s natural resources. Acid rain is a result of sulfur (S) and nitrogen (N) compounds produced from fossil fuel combustion, motor vehicles, and agricultural practices. The AT i
Authors
Gregory B. Lawrence, Timothy J. Sullivan, Douglas A. Burns, Scott W. Bailey, Bernard J. Cosby, Martin Dovciak, Holly A. Ewing, Todd C. McDonnell, Rakesh Minocha, Rachel Riemann, Juliana Quant, Karen C. Rice, Jason Siemion, Kathleen C. Weathers
Long-term soil monitoring at U.S. Geological Survey reference watersheds
Monitoring the environment by making repeated measurements through time is essential to evaluate and track the health of ecosystems (fig. 1). Long-term datasets produced by such monitoring are indispensable for evaluating the effectiveness of environmental legislation and for designing mitigation strategies to address environmental changes in an era when human activities are altering the environme
Authors
Michael R. McHale, Jason Siemion, Gregory B. Lawrence, Alisa Mast
Evaluating the efficiency of environmental monitoring programs
Statistical uncertainty analyses can be used to improve the efficiency of environmental monitoring, allowing sampling designs to maximize information gained relative to resources required for data collection and analysis. In this paper, we illustrate four methods of data analysis appropriate to four types of environmental monitoring designs. To analyze a long-term record from a single site, we app
Authors
Carrie R. Levine, Ruth D. Yanai, Gregory G. Lampman, Douglas A. Burns, Charles T. Driscoll, Gregory B. Lawrence, Jason Lynch, Nina Schoch
Wetlands serve as natural sources for improvement of stream ecosystem health in regions affected by acid deposition
For over 40 years, acid deposition has been recognized as a serious international environmental problem, but efforts to restore acidified streams and biota have had limited success. The need to better understand the effects of different sources of acidity on streams has become more pressing with the recent increases in surface water organic acids, or 'brownification' associated with climate change
Authors
Katrina L Pound, Gregory B. Lawrence, Sophia I. Passy
Measuring environmental change in forest ecosystems by repeated soil sampling: a North American perspective
Environmental change is monitored in North America through repeated measurements of weather, stream and river flow, air and water quality, and most recently, soil properties. Some skepticism remains, however, about whether repeated soil sampling can effectively distinguish between temporal and spatial variability, and efforts to document soil change in forest ecosystems through repeated measuremen
Authors
Gregory B. Lawrence, Ivan J. Fernandez, Daniel D. Richter, Donald S. Ross, Paul W. Hazlett, Scott W. Bailey, Rock Oiumet, Richard A.F. Warby, Arthur H. Johnson, Henry Lin, James M. Kaste, Andrew G. Lapenis, Timothy J. Sullivan
Use of soil-streamwater relationships to assess regional patterns of acidic deposition effects in the northeastern USA
Declines of acidic deposition levels by as much as 50% since 1990 have led to partial recovery of surface waters in the northeastern USA but continued depletion of soil calcium through this same period suggests a disconnection between soil and surface water chemistry. To investigate the role of soil-surface water interactions in recovery from acidification, the first regional survey to directly re
Authors
Jason Siemion, Gregory B. Lawrence, Peter S. Murdoch
Climate warming shifts carbon allocation from stemwood to roots in calcium-depleted spruce forests
Increased greening of northern forests, measured by the Normalized Difference Vegetation Index (NDVI), has been presented as evidence that a warmer climate has increased both net primary productivity (NPP) and the carbon sink in boreal forests. However, higher production and greener canopies may accompany changes in carbon allocation that favor foliage or fine roots over less decomposable woody bi
Authors
Andrei Gennady Lapenis, Gregory B. Lawrence, Alexander Heim, Chengyang Zheng, Walter Shortle
Science and Products
Filter Total Items: 108
Regional growth decline of sugar maple (Acer saccharum) and its potential causes
Sugar maple (Acer saccharum Marsh) has experienced poor vigor, regeneration failure, and elevated mortality across much of its range, but there has been relatively little attention to its growth rates. Based on a well-replicated dendrochronological network of range-centered populations in the Adirondack Mountains (USA), which encompassed a wide gradient of soil fertility, we observed that the majo
Authors
Daniel A. Bishop, Colin M. Beier, Neil Pederson, Gregory B. Lawrence, John C Stella, Timothy J. Sullivan
Photosynthetic and growth response of sugar maple (Acer saccharum Marsh.) mature trees and seedlings to calcium, magnesium, and nitrogen additions in the Catskill Mountains, NY, USA
Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arr
Authors
Bahram Momen, Shawna J Behling, Gregory B. Lawrence, Joseph H Sullivan
Declining acidic deposition begins reversal of forest-soil acidification in the northeastern U.S. and eastern Canada
Decreasing trends in acidic deposition levels over the past several decades have led to partial chemical recovery of surface waters. However, depletion of soil Ca from acidic deposition has slowed surface water recovery and led to the impairment of both aquatic and terrestrial ecosystems. Nevertheless, documentation of acidic deposition effects on soils has been limited, and little is known regard
Authors
Gregory B. Lawrence, Paul W. Hazlett, Ivan J. Fernandez, Rock Ouimet, Scott W. Bailey, Walter C. Shortle, Kevin T. Smith, Michael R. Antidormi
Coastal plain pond water quality and mercury contend of biota of the Long Island Central Pine Barrens and Mashomack Preserve: Effects of atmospheric deposition and human development
Pine barrens are considered an imperiled ecosystem in the northeastern U.S. The Suffolk County Pine Barrens, once the second largest in the Northeast, were substantially reduced and fragmented by development during the 20th century. The coastal plain ponds being considered in this study occur in central Suffolk County within the Long Island Central Pine Barrens region. This highly unique natural e
Authors
Gregory B. Lawrence, Jason Siemion, Oksana P. Lane
Inter-laboratory variation in the chemical analysis of acidic forest soil reference samples from eastern North America
Long-term forest soil monitoring and research often requires a comparison of laboratory data generated at different times and in different laboratories. Quantifying the uncertainty associated with these analyses is necessary to assess temporal changes in soil properties. Forest soil chemical properties, and methods to measure these properties, often differ from agronomic and horticultural soils. S
Authors
Donald S. Ross, Scott W Bailiey, Russell D Briggs, Johanna Curry, Ivan J. Fernandez, Guinevere Fredriksen, Christine L. Goodale, Paul W. Hazlett, Paul R Heine, Chris E. Johnson, John T Larson, Gregory B. Lawrence, Randy K Kolka, Rock Ouimet, D Pare, Daniel D. Richter, Charles D Shirmer, Richard A.F. Warby
Acidic deposition along the Appalachian Trail corridor and its effects on acid-sensitive terrestrial and aquatic resources
The Appalachian National Scenic Trail (AT), a unit of the National Park Service (NPS), spans nearly 2,200 miles from Georgia to Maine, encompassing a diverse range of ecosystems. Acidic deposition (acid rain) threatens the AT’s natural resources. Acid rain is a result of sulfur (S) and nitrogen (N) compounds produced from fossil fuel combustion, motor vehicles, and agricultural practices. The AT i
Authors
Gregory B. Lawrence, Timothy J. Sullivan, Douglas A. Burns, Scott W. Bailey, Bernard J. Cosby, Martin Dovciak, Holly A. Ewing, Todd C. McDonnell, Rakesh Minocha, Rachel Riemann, Juliana Quant, Karen C. Rice, Jason Siemion, Kathleen C. Weathers
Long-term soil monitoring at U.S. Geological Survey reference watersheds
Monitoring the environment by making repeated measurements through time is essential to evaluate and track the health of ecosystems (fig. 1). Long-term datasets produced by such monitoring are indispensable for evaluating the effectiveness of environmental legislation and for designing mitigation strategies to address environmental changes in an era when human activities are altering the environme
Authors
Michael R. McHale, Jason Siemion, Gregory B. Lawrence, Alisa Mast
Evaluating the efficiency of environmental monitoring programs
Statistical uncertainty analyses can be used to improve the efficiency of environmental monitoring, allowing sampling designs to maximize information gained relative to resources required for data collection and analysis. In this paper, we illustrate four methods of data analysis appropriate to four types of environmental monitoring designs. To analyze a long-term record from a single site, we app
Authors
Carrie R. Levine, Ruth D. Yanai, Gregory G. Lampman, Douglas A. Burns, Charles T. Driscoll, Gregory B. Lawrence, Jason Lynch, Nina Schoch
Wetlands serve as natural sources for improvement of stream ecosystem health in regions affected by acid deposition
For over 40 years, acid deposition has been recognized as a serious international environmental problem, but efforts to restore acidified streams and biota have had limited success. The need to better understand the effects of different sources of acidity on streams has become more pressing with the recent increases in surface water organic acids, or 'brownification' associated with climate change
Authors
Katrina L Pound, Gregory B. Lawrence, Sophia I. Passy
Measuring environmental change in forest ecosystems by repeated soil sampling: a North American perspective
Environmental change is monitored in North America through repeated measurements of weather, stream and river flow, air and water quality, and most recently, soil properties. Some skepticism remains, however, about whether repeated soil sampling can effectively distinguish between temporal and spatial variability, and efforts to document soil change in forest ecosystems through repeated measuremen
Authors
Gregory B. Lawrence, Ivan J. Fernandez, Daniel D. Richter, Donald S. Ross, Paul W. Hazlett, Scott W. Bailey, Rock Oiumet, Richard A.F. Warby, Arthur H. Johnson, Henry Lin, James M. Kaste, Andrew G. Lapenis, Timothy J. Sullivan
Use of soil-streamwater relationships to assess regional patterns of acidic deposition effects in the northeastern USA
Declines of acidic deposition levels by as much as 50% since 1990 have led to partial recovery of surface waters in the northeastern USA but continued depletion of soil calcium through this same period suggests a disconnection between soil and surface water chemistry. To investigate the role of soil-surface water interactions in recovery from acidification, the first regional survey to directly re
Authors
Jason Siemion, Gregory B. Lawrence, Peter S. Murdoch
Climate warming shifts carbon allocation from stemwood to roots in calcium-depleted spruce forests
Increased greening of northern forests, measured by the Normalized Difference Vegetation Index (NDVI), has been presented as evidence that a warmer climate has increased both net primary productivity (NPP) and the carbon sink in boreal forests. However, higher production and greener canopies may accompany changes in carbon allocation that favor foliage or fine roots over less decomposable woody bi
Authors
Andrei Gennady Lapenis, Gregory B. Lawrence, Alexander Heim, Chengyang Zheng, Walter Shortle