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1. Forest Inventory of a Northern Hardwood Forest: Bird Area, 1991 - present, Hubbard Brook Experimental Forest

   https://doi.org/10.6073/pasta/58dfdebfd1b6440510def2394ab92c53  

   Battles, John J; Cleavitt, Natalie (January 2022, Environmental Data Initiative)

   The forest inventory surveys in the bird area were initiated in 1981 and transects were made permanent in 1991 by Tom Siccama who created and designed this tree survey. The inventory is representative of approximately 2.5 km2 of mid elevation northern hardwood forest. The data set is particularly geared toward producing accurate mortality and recruitment estimates. It consists of a total inventory of all trees greater than or equal to 10 cm dbh within each of four 10 m wide belt transects. The parallel transects are placed approximately 200 m apart and 290° bearing in an east-west direction for 2200 to 2900 m. In 1991, each live stem greater than or equal to 10 cm dbh was tagged with a unique number. Tree vigor is assessed every two years and diameter is remeasured every ten years. Every two years, new tags are placed on stems that have grown into the 10 cm diameter class. A survey of smaller trees (greater than or equal to 2 to less than 10 cm dbh) was first taken in 1991 and is resurveyed every ten years. This dataset includes 1991 and subsequent samplings. Data from an earlier sampling in 1981 can be found in: Sherry, T., D. Holmes, and T. Siccama. 2019. Forest Inventory of a Northern Hardwood Forest: Bird Area at the Hubbard Brook Experimental Forest, 1981 ver 7. Environmental Data Initiative. https://doi.org/10.6073/pasta/206b98f6553f1ff95cf584dd2185554e (Accessed 2021-09-16). These data were gathered as part of the Hubbard Brook Ecosystem Study (HBES). The HBES is a collaborative effort at the Hubbard Brook Experimental Forest, which is operated and maintained by the USDA Forest Service, Northern Research Station. These data have been used in the following publication: Siccama, T.G., Fahey, T.J., Johnson, C.E., Sherry, T.W., Denny, E.G., Girdler, E.B., Likens, G.E., and Schwarz, P.A. 2007. Population and biomass dynamics of trees in a northern hardwood forest at Hubbard Brook. Can. J. For. Res. 37(4): 737–749. doi:10.1139/X06-261. 

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2. Forest Inventory of a Northern Hardwood Forest: Bird Area, 1991 - present, Hubbard Brook Experimental Forest

   https://doi.org/10.6073/pasta/b3fd0fc3143dd573bfbb161eda9119a1  

   Battles, John J; Cleavitt, Natalie (January 2024, Environmental Data Initiative)

   The forest inventory surveys in the bird area were initiated in 1981 and transects were made permanent in 1991 by Tom Siccama who created and designed this tree survey. The inventory is representative of approximately 2.5 km2 of mid elevation northern hardwood forest. The data set is particularly geared toward producing accurate mortality and recruitment estimates. It consists of a total inventory of all trees greater than or equal to 10 cm dbh within each of four 10 m wide belt transects. The parallel transects are placed approximately 200 m apart and 290° bearing in an east-west direction for 2200 to 2900 m. In 1991, each live stem greater than or equal to 10 cm dbh was tagged with a unique number. Tree vigor is assessed every two years and diameter is remeasured every ten years. Every two years, new tags are placed on stems that have grown into the 10 cm diameter class. This dataset includes 1991 and subsequent samplings. These detailed tree status data provide a high resolution assessment of tree vital rates, particularly recruitment and mortality rates. The data show an increase in both mortality and recruitment over the 30 year measure time (1991-2021). The number of unhealthy trees has also increased to about 8% of the live trees. The measure period includes notable disturbances, particularly the 2013 microburst impacted the west end of lines 5 and 9, and a saddled prominent outbreak concurrent with drought conditions in 2020. Data from an earlier sampling in 1981 (pre-tagging of individual trees) can be found in: Sherry, T., D. Holmes, and T. Siccama. 2019. Forest Inventory of a Northern Hardwood Forest: Bird Area at the Hubbard Brook Experimental Forest, 1981 ver 7. Environmental Data Initiative. https://doi.org/10.6073/pasta/206b98f6553f1ff95cf584dd2185554e (Accessed 2021-09-16). These data were gathered as part of the Hubbard Brook Ecosystem Study (HBES). The HBES is a collaborative effort at the Hubbard Brook Experimental Forest, which is operated and maintained by the USDA Forest Service, Northern Research Station. These data have been used in the following publication: Siccama, T.G., Fahey, T.J., Johnson, C.E., Sherry, T.W., Denny, E.G., Girdler, E.B., Likens, G.E., and Schwarz, P.A. 2007. Population and biomass dynamics of trees in a northern hardwood forest at Hubbard Brook. Can. J. For. Res. 37(4): 737–749. doi:10.1139/X06-261. 

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3. Forest Inventory of a Northern Hardwood Forest: Bird Area at the Hubbard Brook Experimental Forest, 1981

   https://doi.org/10.6073/pasta/18a5a1790d985b38a47a4c79c2f673ef  

   Sherry, Thomas W; Holmes, Richard T; Siccama, Thomas G (January 2024, Environmental Data Initiative)

   The forest inventory surveys in the bird area were initiated in 1981 and transects were made permanent in 1991. The inventory is representative of approximately 2.5 km-squared of mid elevation northern hardwood forest. It consists of a total inventory of all trees >=10 cm dbh, within each of four 10 m wide belt transects. The parallel transects are placed approximately 200 m apart and run roughly in an east-west direction for 2200 to 2900 m. In 1991, each live stem >=10 cm dbh was tagged with a unique number. Tree vigor is assessed every two years and diameter is remeasured every ten years. Every two years, new tags are placed on stems that have grown into the 10 cm diameter class. A survey of smaller trees (>=2 to <10 cm dbh) was first taken in 1991 and is resurveyed every ten years. This dataset includes the initial inventory values measured in 1981. The full timeline of tree inventory data for this site is available at https://doi.org/10.6073/pasta/58dfdebfd1b6440510def2394ab92c53 These data were gathered as part of the Hubbard Brook Ecosystem Study (HBES). The HBES is a collaborative effort at the Hubbard Brook Experimental Forest, which is operated and maintained by the USDA Forest Service, Northern Research Station. 

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4. Deep forest: Neural network reconstruction of the Lyman-α forest

   https://doi.org/10.1093/mnras/stab2041  

   Huang, Lawrence; Croft, Rupert A; Arora, Hitesh (August 2021, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   ABSTRACT We explore the use of Deep Learning to infer physical quantities from the observable transmitted flux in the Ly α forest. We train a Neural Network using redshift z = 3 outputs from cosmological hydrodynamic simulations and mock data sets constructed from them. We evaluate how well the trained network is able to reconstruct the optical depth for Ly α forest absorption from noisy and often saturated transmitted flux data. The Neural Network outperforms an alternative reconstruction method involving log inversion and spline interpolation by approximately a factor of 2 in the optical depth root mean square error. We find no significant dependence in the improvement on input data signal to noise, although the gain is greatest in high optical depth regions. The Ly α forest optical depth studied here serves as a simple, one dimensional, example but the use of Deep Learning and simulations to approach the inverse problem in cosmology could be extended to other physical quantities and higher dimensional data. 

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5. Toward a forest transition across the Brazilian Atlantic Forest biome

   https://doi.org/10.3389/ffgc.2023.1071495  

   Bicudo da Silva, Ramon Felipe; Moran, Emilio; Viña, Andrés; Millington, James D.; Dou, Yue; Vieira, Simone A.; Lopez, Maria Claudia; Liu, Jianguo (June 2023, Frontiers in Forests and Global Change)

   The world has entered the United Nations Decade on Ecosystem Restoration (2021–2030), yet many regions of the world still face environmental degradation. In this context a question arises: under what conditions may a given region shift from a trajectory of environmental degradation to environmental recovery? Answering this question constitutes an important endeavor for the scientific community, policymakers, and organizations leading the planning and implementation of restoration projects. This study examines some of the human-environment conditions underpinning the net gains in natural forest cover in a region that has experienced environmental degradation: the Atlantic Forest biome, Brazil. Using land-use/cover (LULC) data, we assessed the loss and successive gain in forest cover during the 1987–2001 and 2001–2015 periods. Municipality-level statistics on agriculture and economy, together with LULC and biophysical data, were used to develop models for assessing forest cover trajectories. Of the 1,972 municipalities experiencing net forest loss during the 1987–2001 period, 59% shifted their trajectory to a net gain during the 2001–2015 period. This shift, known as forest transition, followed a complex socio-economic pathway characterized by (i) the stagnation of traditional agricultural activities favoring the replacement of pasturelands by mechanized agriculture, and (ii) the emergence of non-agricultural rural activities together with multifunctional landscapes. Furthermore, a trend of decrease in precipitation seems to be associated with land abandonment, thus, favoring the return of natural vegetation. Our findings suggest that forest transition at the biome level is possible if environmental and land regulations take advantage of specific context-dependent situations that foster net forest gains. 

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