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We are conducting nutrient manipulations in three study sites in the White Mountain National Forest in New Hampshire: Bartlett Experimental Forest, Hubbard Brook Experimental Forest, and Jeffers Brook. We monitored foliar chemistry in 13 of our stands (including HBCa and excluding C3) pre-treatment (2008-2010) and post-treatment (2014-2016 and 2021-22). In 2021-22, we also measured specific leaf area, leaf dry matter content, carbon isotope composition, and stomatal density. We found that foliar N concentrations were higher with N addition and foliar P concentrations were higher with P addition. More interestingly, P addition reduced foliar N concentrations and N addition reduced foliar P concentrations. Some interactive effects were observed (i.e. NxP, Species x N, Species x P, Species x N x P). This dataset contains pre- and post- treatment foliar chemistry and trait data, and data from the analysis of quality control standard samples. Changes to pre-treatment data from version 1 include switching white birch trees #8272 and #8252 in stand JBM plots 2 and 3 (8272 is now in the nitrogen plot and 8252 is now in the control plot), correcting the species of tree #1628 in stand HBCa plot 1 (changed from red maple to sugar maple) and tree #8457 in stand HBO plot 3 (changed from sugar maple to red maple), and updating nutrient concentrations for C8 plot 3 sugar maple trees #28 and #30 to include averages of subsamples re-run in 2022. Tree tags were also updated to the tag ID present during the 2023 tree inventory. Additional detail on the MELNHE project, including a datatable of site descriptions and a pdf file with the project description and diagram of plot configuration can be found in this data package: https://portal.edirepository.org/nis/mapbrowse?scope=knb-lter-hbr&identifier=344 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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Sugar Maple Regeneration in New Hampshire, 2019-2023
Overview: These data sets are the culmination of a five-year community science project done in collaboration with the Society for Protection of NH Forests. Co-authors on the resulting paper were: Carrie Deegan, Sarah Thorne, Ana Suppé, Kimberly L. Colson and Wanda Rice. Funding was provided by: Engaged Research Grant from the Einhorn Center for Community Engagement at Cornell University 2019 - 2023; Public Engagement with Science Grant (NSF grant #1713204) subcontract from Hubbard Brook Research Foundation; USDA Climate Hub; NSF-REU supplement under the HBR LTER (NSF grant #1637685) in 2021 and 2022 and HBR LTER in 2023 (NSF grant #2224545 ). Undergraduate students who helped on the project: Katie Sims, Alex Ding, Esmée deCortie, Sage Wentzell-Brehme, Colin Craig, Linda Mahecha, Roxy Moore. Community volunteers who contributed to field data collection and project meetings: Paul Doscher, Dave Heuss, Kim Sharp, Chris Brown, Tim Kendrick, Dan Poor, Rickey Poor, and Blaine Kopp. The study was conducted in four mature forest stands with a notable sugar maple component owned and managed by the Society for Protection of New Hampshire Forests (Forest Society) and spanning most of the latitudinal gradient in the state. Plots were established in autumn of 2018. In general, 12 plot locations were established for each of the four forest stands. Plots are spatially-uniform and placed as close to a 100 m grid system as possible with the restriction that the plot had to include three canopy sugar maple trees. The plots are 0.05 hectares or 500 m2 in size measured in a 12.62 m radius circular plot. Marked_sdlg_site_EDI: This data set contains survival, leaf area and leaf damage for 1191 sugar maple seedlings at four sites in New Hampshire. The sugar maple seedlings were two years old at the time of marking in 2019 and were from the 2017 mast year. The study followed the seedlings on 12 plots per site for 5 years (2019-2023). The data file also contains plot and site variables for topography, soil chemistry and tree density and sugar maple dominance. Some of the main findings from the study were the importance of site, initial leaf area and leaf damage to seedling survival. Litter_coll_ForestSoc_2yr: Leaves and seeds were collected from half of the plots (N=6) per site using three collectors. Count and dry weight were obtained for the leaves and counts for any seeds. This data set contains the main autumn collection data for 2019 and 2020. The were 20 tree species included over the four sites. There was a pattern of greater productivity in the southern site (greatest number of leaves) and decreased productivity in the northern site (lowest dry mass of leaves). Seed production for sugar maple was higher in 2019. Sweep_ForestSoc: Sapling layers were generally open with only 281 saplings from all plots. Kauffmann had the densest and most diverse sapling layer. The saplings were only measured once in 2019. Tagged_trees_ForestSoc: The data set includes growth (4 year) and vigor data (every other year) for 1335 trees in four study sites in New Hampshire. The data set includes data for 16 tree species tagged in 2019 and assessed in 2021 and 2023. At all sites, sugar maple growth was slower than average tree growth and mortality for sugar maple was higher than the average tree. This data set does not include data for trees that died during the study and therefore do not have growth data (96 trees). Common_garden_sdlgs: This data set includes harvest data for 50 sugar maple seedlings grown in a common garden experiment with soil from the four study sites taken from two microsites: sugar maple dominated and dominated by other species. The experimental setup had two controls. One control was the live soil from the site where the seedlings were obtained (native soil control). A second control contained a mix of sugar maple soil from the four sites that had been sterilized (pathogen free control). The experiment did not demonstrate a microsite difference for seedling growth but rather sites differed with the most nutrient rich soil resulting in larger seedlings. Overall, the experiment did not support a significant role of soil pathogens in explaining seedling survival differences between sites. ACSA_samaras_2019: This data table gives counts and condition of the samaras collected at the four study sites in autumn 2019, which represented the largest seed year during the study time. This data is useful for comparing differences in pre-dispersal damage to the seeds and seed production across sites. 2020_germinant_counts: This data table gives counts of newly germinated sugar maple seedlings at the plots with collectors (odd numbered plots). Sites were visited 14-18 May 2020. These data are used for comparing initial seedling densities across sites and the number of seedlings compared to the number of seeds for those plots, which gives an idea of post-dispersal survival.
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- PAR ID:
- 10573307
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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