The purpose of this study is to increase our understanding of ecosystem nitrogen dynamics in response to elevated nitrogen inputs. With atmospheric nitrogen deposition in the Northeastern United States currently at 10 to 20 times above historic background levels, it is possible that excessive nitrogen inputs could saturate the retention capacity of a forest ecosystem. Potential effects of nitrogen saturation include increased nitrate leaching and simultaneous base cation losses, soil acidification, altered fluxes of trace gases and forest decline. Two adjacent stands were chosen for the study: an even-aged red pine (Pinus resinosa Ait.) stand planted in 1926 and a 50-year-old mixed hardwood stand that had regenerated naturally after clearcutting in approximately 1945. The hardwood stand is dominated by black and red oak (Quercus velutina Lam.; Q. rubra L.) with significant amounts of black birch (Betula lenta L.), red maple (Acer rubrum L.) and American beech (Fagus grandifolia Ehrh.). The dominant soil types are stony- to sandy-loams formed from glacial till, and are classified as Typic Dystrochrepts of the Canton or Montauk series. Four treated plots were established within each stand: control, low N, low N plus sulfur (N+S) and high N. Each plot measures 30 x 30 meters (0.09 ha) and is divided into thirty-six 5 x 5 m subplots.

A canopy nitrogen map was created for the Hubbard Brook Experimental Forest and watersheds using airborne imaging spectrometer data collected by SpecTIR LLC (Reno, NV) on August 7, 2012, and associated field data. Leaf samples collected in the field were analyzed for nitrogen concentration, scaled to plot (whole canopy) level, and related to airborne imaging spectrometer reflectance data using partial least squares regression modeling to derive spatially explicit estimates of canopy nitrogen concentration (mass-based) for the spatial extent of the airborne imagery.

The purpose of this study is to increase our understanding of ecosystem nitrogen dynamics in response to elevated nitrogen inputs. With atmospheric nitrogen deposition in the Northeastern United States currently at 10 to 20 times above historic background levels, it is possible that excessive nitrogen inputs could saturate the retention capacity of a forest ecosystem. Potential effects of nitrogen saturation include increased nitrate leaching and simultaneous base cation losses, soil acidification, altered fluxes of trace gases and forest decline. Two adjacent stands were chosen for the study: an even-aged red pine (Pinus resinosa Ait.) stand planted in 1926 and a 50-year-old mixed hardwood stand that had regenerated naturally after clearcutting in approximately 1945. The hardwood stand is dominated by black and red oak (Quercus velutina Lam.; Q. rubra L.) with significant amounts of black birch (Betula lenta L.), red maple (Acer rubrum L.) and American beech (Fagus grandifolia Ehrh.). The dominant soil types are stony- to sandy-loams formed from glacial till, and are classified as Typic Dystrochrepts of the Canton or Montauk series. Four treated plots were established within each stand: control, low N, low N plus sulfur (N+S) and high N. Each plot measures 30 x 30 meters (0.09 ha) and is divided into thirty-six 5 x 5 m subplots.

The purpose of this study is to increase our understanding of ecosystem nitrogen dynamics in response to elevated nitrogen inputs. With atmospheric nitrogen deposition in the Northeastern United States currently at 10 to 20 times above historic background levels, it is possible that excessive nitrogen inputs could saturate the retention capacity of a forest ecosystem. Potential effects of nitrogen saturation include increased nitrate leaching and simultaneous base cation losses, soil acidification, altered fluxes of trace gases and forest decline. Two adjacent stands were chosen for the study: an even-aged red pine (Pinus resinosa Ait.) stand planted in 1926 and a 50-year-old mixed hardwood stand that had regenerated naturally after clearcutting in approximately 1945. The hardwood stand is dominated by black and red oak (Quercus velutina Lam.; Q. rubra L.) with significant amounts of black birch (Betula lenta L.), red maple (Acer rubrum L.) and American beech (Fagus grandifolia Ehrh.). The dominant soil types are stony- to sandy-loams formed from glacial till, and are classified as Typic Dystrochrepts of the Canton or Montauk series. Four treated plots were established within each stand: control, low N, low N plus sulfur (N+S) and high N. Each plot measures 30 x 30 meters (0.09 ha) and is divided into thirty-six 5 x 5 m subplots.

Airborne remote sensing data were acquired specifically for the EPSCoR NH Ecosystems and Society project to provide vegetation biometric and land surface optical properties at the landscape-scale. Data were acquired for targeted field sites that include the Lamprey River Watershed, the Hubbard Brook Experimental Forest and the Bartlett Experimental Forest, where soil and aquatic sensors are deployed and intensive field sample plots have been established to measure a range of vegetation and land surface properties. Two image data collection campaigns were deployed—one in summer (August 2012) to capture peak growing season conditions in the state, and one in winter (Feb/March 2013). This data package contains the flightlines for Hubbard Brook. Data are georegistered and atmospherically corrected to surface reflectance for August 7, 2012.

Airborne remote sensing data were acquired specifically for the EPSCoR NH Ecosystems and Society project to provide vegetation biometric and land surface optical properties at the landscape-scale. Data were acquired for targeted field sites that include the Lamprey River Watershed, the Hubbard Brook Experimental Forest and the Bartlett Experimental Forest, where soil and aquatic sensors are deployed and intensive field sample plots have been established to measure a range of vegetation and land surface properties. Two image data collection campaigns were deployed—one in summer (August 2012) to capture peak growing season conditions in the state, and one in winter (Feb/March 2013). This data package contains the flightlines for Hubbard Brook. Data are georegistered and atmospherically corrected to surface reflectance for February 22, 2013.

Airborne remote sensing data were acquired specifically for the EPSCoR NH Ecosystems and Society project to provide vegetation biometric and land surface optical properties at the landscape-scale. Data were acquired for targeted field sites that include the Lamprey River Watershed, the Hubbard Brook Experimental Forest and the Bartlett Experimental Forest, where soil and aquatic sensors are deployed and intensive field sample plots have been established to measure a range of vegetation and land surface properties. Two image data collection campaigns were deployed—one in summer (August 2012) to capture peak growing season conditions in the state, and one in winter (Feb/March 2013). This data package contains the flightlines for Hubbard Brook. Data are georegistered and atmospherically corrected to surface reflectance for March 9, 2013.

All data on soil carbon flux (“soil respiration”) collected using chamber-based methods at Harvard Forest from a range of observational and experimental plots were collated, their units were harmonized, and geographic (locations) and environmental characteristics (soil series, drainage class, soil temperature, soil moisture, vegetation type, etc.) were identified for each observation. This yielded a dataset with 106,192 observations of soil respiration taken between 1991 and 2008. These data provide a unique resource for exploring spatial and temporal patterns in soil respiration in a range of common New England forest types. For the Giasson, et al. (2013) publication, we also used 24 site-years of eddy covariance measurements from two Harvard Forest sites (EMS and Hemlock towers) to examine the relationship between soil and ecosystem respiration. Here, we present all derived/synthetic datasets associated with the manuscript. M.-A. Giasson, A. M. Ellison, R. D. Bowden, P. M. Crill, E. A. Davidson, J. E. Drake, S. D. Frey, J. L. Hadley, M. Lavine, J. M. Melillo, J. W. Munger, K. J. Nadelhoffer, L. Nicoll, S. V. Ollinger, K. E. Savage, P. A. Steudler, J. Tang, R. K. Varner, S. C. Wofsy, D. R. Foster, and A. C. Finzi 2013. Soil respiration in a northeastern US temperate forest: a 22-year synthesis. Ecosphere 4:art140. http://dx.doi.org/10.1890/ES13.00183.1

All data on soil carbon flux (“soil respiration”) collected using chamber-based methods at Harvard Forest from a range of observational and experimental plots were collated, their units were harmonized, and geographic (locations) and environmental characteristics (soil series, drainage class, soil temperature, soil moisture, vegetation type, etc.) were identified for each observation. This yielded a dataset with 106,192 observations of soil respiration taken between 1991 and 2008. These data provide a unique resource for exploring spatial and temporal patterns in soil respiration in a range of common New England forest types. For the Giasson, et al. (2013) publication, we also used 24 site-years of eddy covariance measurements from two Harvard Forest sites (EMS and Hemlock towers) to examine the relationship between soil and ecosystem respiration. Here, we present all derived/synthetic datasets associated with the manuscript. M.-A. Giasson, A. M. Ellison, R. D. Bowden, P. M. Crill, E. A. Davidson, J. E. Drake, S. D. Frey, J. L. Hadley, M. Lavine, J. M. Melillo, J. W. Munger, K. J. Nadelhoffer, L. Nicoll, S. V. Ollinger, K. E. Savage, P. A. Steudler, J. Tang, R. K. Varner, S. C. Wofsy, D. R. Foster, and A. C. Finzi 2013. Soil respiration in a northeastern US temperate forest: a 22-year synthesis. Ecosphere 4:art140. http://dx.doi.org/10.1890/ES13.00183.1

The purpose of this study is to increase our understanding of ecosystem nitrogen dynamics in response to elevated nitrogen inputs. With atmospheric nitrogen deposition in the Northeastern United States currently at 10 to 20 times above historic background levels, it is possible that excessive nitrogen inputs could saturate the retention capacity of a forest ecosystem. Potential effects of nitrogen saturation include increased nitrate leaching and simultaneous base cation losses, soil acidification, altered fluxes of trace gases and forest decline. Two adjacent stands were chosen for the study: an even-aged red pine (Pinus resinosa Ait.) stand planted in 1926 and a 50-year-old mixed hardwood stand that had regenerated naturally after clearcutting in approximately 1945. The hardwood stand is dominated by black and red oak (Quercus velutina Lam.; Q. rubra L.) with significant amounts of black birch (Betula lenta L.), red maple (Acer rubrum L.) and American beech (Fagus grandifolia Ehrh.). The dominant soil types are stony- to sandy-loams formed from glacial till, and are classified as Typic Dystrochrepts of the Canton or Montauk series. Four treated plots were established within each stand: control, low N, low N plus sulfur (N+S) and high N. Each plot measures 30 x 30 meters (0.09 ha) and is divided into thirty-six 5 x 5 m subplots.