Gregory B Lawrence (Former Employee)
Science and Products
Filter Total Items: 109
Forest soil chemistry and terrain attributes in a Catskills watershed Forest soil chemistry and terrain attributes in a Catskills watershed
Knowledge of soil chemistry is useful in assessing the sensitivity of forested areas to natural and anthropogenic disturbances, but characterizing large areas is expensive because of the large sample numbers required and the cost of soil chemical analyses. We collected and chemically analyzed soil samples from 72 sites within a 214-ha watershed in the Catskill Mountains of New York to...
Authors
C.E. Johnson, J. J. Ruiz-Mendez, G.B. Lawrence
Composition of fish communities in relation to stream acidification and habitat in the Neversink River, New York Composition of fish communities in relation to stream acidification and habitat in the Neversink River, New York
The effects of acidification in lotic systems are not well documented. Spatial and temporal variability of habitat and water quality complicate the evaluation of acidification effects in streams and rivers. The Neversink River in the Catskill Mountains of southeastern New York, the tributaries of which vary from well buffered to severely acidified, provided an opportunity to investigate...
Authors
Barry P. Baldigo, G.B. Lawrence
Atmospheric nitrogen in the Mississippi River Basin: Amissions, deposition and transport Atmospheric nitrogen in the Mississippi River Basin: Amissions, deposition and transport
Atmospheric deposition of nitrogen has been cited as a major factor in the nitrogen saturation of forests in the north-eastern United States and as a contributor to the eutrophication of coastal waters, including the Gulf of Mexico near the mouth of the Mississippi River. Sources of nitrogen emissions and the resulting spatial patterns of nitrogen deposition within the Mississippi River...
Authors
G.B. Lawrence, D. A. Goolsby, W.A. Battaglin, G.J. Stensland
Soil calcium status and the response of stream chemistry to changing acidic deposition rates Soil calcium status and the response of stream chemistry to changing acidic deposition rates
Despite a decreasing trend in acidic deposition rates over the past two to three decades, acidified surface waters in the northeastern United States have shown minimal changes. Depletion of soil Ca pools has been suggested as a cause, although changes in soil Ca pools have not been directly related to long-term records of stream chemistry. To investigate this problem, a comprehensive...
Authors
G.B. Lawrence, Mark B. David, Gary M. Lovett, Peter S. Murdoch, Douglas A. Burns, John L. Stoddard, Barry P. Baldigo, J.H. Porter, A.W. Thompson
Soil-calcium depletion linked to acid rain and forest growth in the eastern United States Soil-calcium depletion linked to acid rain and forest growth in the eastern United States
Since the discovery of acid rain in the 1970's, scientists have been concerned that deposition of acids could cause depletion of calcium in forest soils. Research in the 1980's showed that the amount of calcium in forest soils is controlled by several factors that are difficult to measure. Further research in the 1990's, including several studies by the U.S. Geological Survey, has shown...
Authors
Gregory B. Lawrence, T.G. Huntington
Streams in Catskill Mountains still susceptible to acid rain Streams in Catskill Mountains still susceptible to acid rain
Precipitation in North America has become less acidic over the past 2 decades because of reduced power plant emissions and compliance with the Clean Air Act Amendments [Sirois, 19937rsqb;. The 1990 Clean Air Act Amendments were developed to reduce the acidity of sensitive surface waters, which are primarily in upland forested environments, where acidified waters and associated high...
Authors
Douglas A. Burns, G.B. Lawrence, Peter S. Murdoch
Effect of chronic nitrogen additions on soil nitrogen fractions in red spruce stands Effect of chronic nitrogen additions on soil nitrogen fractions in red spruce stands
The responses of temperate and boreal forest ecosystems to increased nitrogen (N) inputs have been varied, and the responses of soil N pools have been difficult to measure. In this study, fractions and pool sizes of N were determined in the forest floor of red spruce stands at four sites in the northeastern U.S. to evaluate the effect of increased N inputs on forest floor N. Two of the...
Authors
M.B. David, A.M. Cupples, G.B. Lawrence, G. Shi, K. Vogt, P.M. Wargo
Relation of climate change to the acidification of surface waters by nitrogen deposition Relation of climate change to the acidification of surface waters by nitrogen deposition
Abrupt increases and decreases in mean seasonal and annual stream NO3- concentrations during the period of record (1983-1995) at Biscuit Brook, a headwater stream in the Catskill Mountains of New York, have provided an opportunity to study the biogeochemical processes that control NO3- movement through forested watersheds. The Catskills receive the highest rate of NO3- deposition in the...
Authors
Peter S. Murdoch, Douglas A. Burns, G.B. Lawrence
Streams in catskill mountains still susceptible to acid rain Streams in catskill mountains still susceptible to acid rain
[No abstract available]
Authors
Douglas A. Burns, G.B. Lawrence, Peter S. Murdoch
Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams
Groundwater and stream water data collected at three headwater catchments in the Neversink River watershed indicate that base flow is sustained by groundwater from two sources: a shallow flow system within the till and soil and a deep flow system within bedrock fractures and bedding planes that discharges as perennial springs. Data from eight wells finished near the till/bedrock...
Authors
Douglas A. Burns, Peter S. Murdoch, Gregory B. Lawrence, Robert L. Michel
Combining digital spatial data with hydrologic measurements to interpret controls of stream chemistry in large watersheds Combining digital spatial data with hydrologic measurements to interpret controls of stream chemistry in large watersheds
No abstract available.
Authors
Yvonne H. Baevsky, Gregory B. Lawrence, David M. Wolock, Douglas A. Burns, Peter S. Murdoch
Acidic deposition, cation mobilization, and biochemical indicators of stress in healthy red spruce Acidic deposition, cation mobilization, and biochemical indicators of stress in healthy red spruce
Dendrochemical and biochemical markers link stress in apparently healthy red spruce trees (Picea rubens) to acidic deposition. Acidic deposition to spruce forests of the northeastern USA increased sharply during the 1960s. Previous reports related visible damage of trees at high elevations to root and soil processes. In this report, dendrochemical and foliar biochemical markers indicate
Authors
W.C. Shortle, K.T. Smith, R. Minocha, G.B. Lawrence, M.B. David
Science and Products
Filter Total Items: 109
Forest soil chemistry and terrain attributes in a Catskills watershed Forest soil chemistry and terrain attributes in a Catskills watershed
Knowledge of soil chemistry is useful in assessing the sensitivity of forested areas to natural and anthropogenic disturbances, but characterizing large areas is expensive because of the large sample numbers required and the cost of soil chemical analyses. We collected and chemically analyzed soil samples from 72 sites within a 214-ha watershed in the Catskill Mountains of New York to...
Authors
C.E. Johnson, J. J. Ruiz-Mendez, G.B. Lawrence
Composition of fish communities in relation to stream acidification and habitat in the Neversink River, New York Composition of fish communities in relation to stream acidification and habitat in the Neversink River, New York
The effects of acidification in lotic systems are not well documented. Spatial and temporal variability of habitat and water quality complicate the evaluation of acidification effects in streams and rivers. The Neversink River in the Catskill Mountains of southeastern New York, the tributaries of which vary from well buffered to severely acidified, provided an opportunity to investigate...
Authors
Barry P. Baldigo, G.B. Lawrence
Atmospheric nitrogen in the Mississippi River Basin: Amissions, deposition and transport Atmospheric nitrogen in the Mississippi River Basin: Amissions, deposition and transport
Atmospheric deposition of nitrogen has been cited as a major factor in the nitrogen saturation of forests in the north-eastern United States and as a contributor to the eutrophication of coastal waters, including the Gulf of Mexico near the mouth of the Mississippi River. Sources of nitrogen emissions and the resulting spatial patterns of nitrogen deposition within the Mississippi River...
Authors
G.B. Lawrence, D. A. Goolsby, W.A. Battaglin, G.J. Stensland
Soil calcium status and the response of stream chemistry to changing acidic deposition rates Soil calcium status and the response of stream chemistry to changing acidic deposition rates
Despite a decreasing trend in acidic deposition rates over the past two to three decades, acidified surface waters in the northeastern United States have shown minimal changes. Depletion of soil Ca pools has been suggested as a cause, although changes in soil Ca pools have not been directly related to long-term records of stream chemistry. To investigate this problem, a comprehensive...
Authors
G.B. Lawrence, Mark B. David, Gary M. Lovett, Peter S. Murdoch, Douglas A. Burns, John L. Stoddard, Barry P. Baldigo, J.H. Porter, A.W. Thompson
Soil-calcium depletion linked to acid rain and forest growth in the eastern United States Soil-calcium depletion linked to acid rain and forest growth in the eastern United States
Since the discovery of acid rain in the 1970's, scientists have been concerned that deposition of acids could cause depletion of calcium in forest soils. Research in the 1980's showed that the amount of calcium in forest soils is controlled by several factors that are difficult to measure. Further research in the 1990's, including several studies by the U.S. Geological Survey, has shown...
Authors
Gregory B. Lawrence, T.G. Huntington
Streams in Catskill Mountains still susceptible to acid rain Streams in Catskill Mountains still susceptible to acid rain
Precipitation in North America has become less acidic over the past 2 decades because of reduced power plant emissions and compliance with the Clean Air Act Amendments [Sirois, 19937rsqb;. The 1990 Clean Air Act Amendments were developed to reduce the acidity of sensitive surface waters, which are primarily in upland forested environments, where acidified waters and associated high...
Authors
Douglas A. Burns, G.B. Lawrence, Peter S. Murdoch
Effect of chronic nitrogen additions on soil nitrogen fractions in red spruce stands Effect of chronic nitrogen additions on soil nitrogen fractions in red spruce stands
The responses of temperate and boreal forest ecosystems to increased nitrogen (N) inputs have been varied, and the responses of soil N pools have been difficult to measure. In this study, fractions and pool sizes of N were determined in the forest floor of red spruce stands at four sites in the northeastern U.S. to evaluate the effect of increased N inputs on forest floor N. Two of the...
Authors
M.B. David, A.M. Cupples, G.B. Lawrence, G. Shi, K. Vogt, P.M. Wargo
Relation of climate change to the acidification of surface waters by nitrogen deposition Relation of climate change to the acidification of surface waters by nitrogen deposition
Abrupt increases and decreases in mean seasonal and annual stream NO3- concentrations during the period of record (1983-1995) at Biscuit Brook, a headwater stream in the Catskill Mountains of New York, have provided an opportunity to study the biogeochemical processes that control NO3- movement through forested watersheds. The Catskills receive the highest rate of NO3- deposition in the...
Authors
Peter S. Murdoch, Douglas A. Burns, G.B. Lawrence
Streams in catskill mountains still susceptible to acid rain Streams in catskill mountains still susceptible to acid rain
[No abstract available]
Authors
Douglas A. Burns, G.B. Lawrence, Peter S. Murdoch
Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams Effect of groundwater springs on NO3− concentrations during summer in Catskill Mountain streams
Groundwater and stream water data collected at three headwater catchments in the Neversink River watershed indicate that base flow is sustained by groundwater from two sources: a shallow flow system within the till and soil and a deep flow system within bedrock fractures and bedding planes that discharges as perennial springs. Data from eight wells finished near the till/bedrock...
Authors
Douglas A. Burns, Peter S. Murdoch, Gregory B. Lawrence, Robert L. Michel
Combining digital spatial data with hydrologic measurements to interpret controls of stream chemistry in large watersheds Combining digital spatial data with hydrologic measurements to interpret controls of stream chemistry in large watersheds
No abstract available.
Authors
Yvonne H. Baevsky, Gregory B. Lawrence, David M. Wolock, Douglas A. Burns, Peter S. Murdoch
Acidic deposition, cation mobilization, and biochemical indicators of stress in healthy red spruce Acidic deposition, cation mobilization, and biochemical indicators of stress in healthy red spruce
Dendrochemical and biochemical markers link stress in apparently healthy red spruce trees (Picea rubens) to acidic deposition. Acidic deposition to spruce forests of the northeastern USA increased sharply during the 1960s. Previous reports related visible damage of trees at high elevations to root and soil processes. In this report, dendrochemical and foliar biochemical markers indicate
Authors
W.C. Shortle, K.T. Smith, R. Minocha, G.B. Lawrence, M.B. David