Search for: All records

Data associated with the publication: Conrad-Rooney E, AB Reinmann, PH Templer. Declining Winter Snowpack Offsets Carbon Storage Enhancement from Growing Season Warming in Northern Temperate Forest Ecosystems. Proceedings of the National Academy of Sciences, 2025. This dataset includes cumulative stem biomass carbon data (from pre-treatment in 2012 until 2022) and annual stem biomass growth rates (not cumulative) for 2015-2022 for the red maple trees at the Climate Change Across Seasons Experiment. 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. 

Data associated with the publication: Conrad-Rooney E, AB Reinmann, PH Templer. Declining Winter Snowpack Offsets Carbon Storage Enhancement from Growing Season Warming in Northern Temperate Forest Ecosystems. Proceedings of the National Academy of Sciences, 2025. This dataset includes soil temperature (winter 2021-2022) and snow depth and frost depth (winter 2022-2023) at the Climate Change Across Seasons Experiment. 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. 

Northeastern US temperate forests are currently net carbon (C) sinks and play an important role offsetting anthropogenic C emissions, but projected climatic changes, including increased temperatures and decreased winter snowpack, may influence this C sink over the next century. Past studies show that growing season warming increases forest C storage through greater soil nutrient availability that contributes to greater rates of net photosynthesis, while reduced winter snowpack induces soil freeze/thaw cycles that reduce tree root vitality, nutrient uptake, and forest C storage. The year-round effects of climate change on this C sink are not well understood. We report here decade-long results from the Climate Change Across Seasons Experiment (CCASE) at the Hubbard Brook Experimental Forest, which determines the combined effects of growing season warming and a smaller winter snowpack on C storage in northern temperate forests. We found after a decade of treatments that growing season warming increases cumulative tree stem biomass C by 63%. However, winter soil freeze/thaw cycles offset half of this growing season warming effect. The amount of C stored in stem biomass of trees experiencing both growing season warming plus smaller winter snowpack is only 31% higher than the reference plots, but this difference is not significant. Our results suggest that current Earth system models are likely to overestimate the C sink capacity of northern temperate forests because they do not incorporate the negative impacts of a shrinking snowpack and increased frequency of soil freeze/thaw cycles on C uptake and storage by trees. 

Within seasonal temperate forests, changes in precipitation structure—its form, duration, and seasonal timing—is a dominant characteristic of climate change. While past research has focused primarily on annual precipitation totals, emerging evidence shows that short-duration extreme precipitation can impact ecosystem carbon, water, and biogeochemical cycling when it coincides with key phenological and physiological transitions. These impacts are mediated by the responses of plant and microbial physiology, aboveground–belowground interactions, and lagged feedbacks as organisms and communities adjust to these extremes. This review focuses on shifts within ecosystem water cycling, within tree growth dynamics (carbon uptake and aboveground–belowground allocation and coordination), within soil biogeochemical cycling, from the loss of winter snow, and in forest structure and community composition. Together, these concepts highlight the urgent need to understand how changes in all aspects of precipitation structure reshape the functioning and resilience of mesic temperate forests. 

Abstract Fragmentation transforms the environment along forest edges. The prevailing narrative, driven by research in tropical systems, suggests that edge environments increase tree mortality and structural degradation resulting in net decreases in ecosystem productivity. We show that, in contrast to tropical systems, temperate forest edges exhibit increased forest growth and biomass with no change in total mortality relative to the forest interior. We analyze >48,000 forest inventory plots across the north-eastern US using a quasi-experimental matching design. At forest edges adjacent to anthropogenic land covers, we report increases of 36.3% and 24.1% in forest growth and biomass, respectively. Inclusion of edge impacts increases estimates of forest productivity by up to 23% in agriculture-dominated areas, 15% in the metropolitan coast, and +2% in the least-fragmented regions. We also quantify forest fragmentation globally, at 30-m resolution, showing that temperate forests contain 52% more edge forest area than tropical forests. Our analyses upend the conventional wisdom of forest edges as less productive than intact forest and call for a reassessment of the conservation value of forest fragments. 

The climate is changing in many temperate forests with the amount of forest area dominated by sugar maple experiencing an insulating snowpack expected to shrink between 49 and 95% compared to 1951-2005 values. A reduced snowpack and increased depth and duration of soil frost can injure or kill fine roots, which are essential for plant water and nutrient uptake. These adverse impacts on tree roots can have important impacts on tree growth and ecosystem carbon sequestration. We evaluated the effects of changing winter climate, including snow and soil frost dynamics, by using tree cores to measure sugar maple radial growth rates in the Soil Freezing Study plots at the Hubbard Brook Experimental Forest. 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. Analysis of these data are published in: Reinmann AB, Susser JR, Demara EMC, and Templer PH. 2019. Declines in northern forest tree growth following snowpack decline and soil freezing. Global Change Biology. 25(2):420-430. https://doi.org/10.1111/gcb.14420 

Root damage, as relative electrolyte leakage, was assessed following winter freeze-thaw cycle experimental treatments in 2014 and 2015 on all Climate Change Across Seasons Experiment (CCASE) plots. Reference (or control) plots are shared with the collaborating Northern Forest DroughtNet experiment. There are six plots total (each 11 x 14m). Two are warmed 5 degrees C throughout the growing season (Plots 3 and 4). Two others are warmed 5 degrees C in the growing season and have snow removed during winter to induce soil freeze/thaw cycles (Plots 5 and 6). Four kilometers (2.5 mi) of heating cable are buried in the soil to warm these four plots. Two additional plots serve as controls for our experiment (Plots 1 and 2). Analysis and results from these data are presented in Sanders-DeMott 2018. 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. Sanders-DeMott, R., Sorensen, P.O., Reinmann, A.B. et al. Growing season warming and winter freeze–thaw cycles reduce root nitrogen uptake capacity and increase soil solution nitrogen in a northern forest ecosystem. Biogeochemistry 137, 337–349 (2018). https://doi.org/10.1007/s10533-018-0422-5 

Fine root nitrogen uptake capacity was measured on excised roots prior to experimental treatment in 2013 and throughout the growing seasons of 2014 and 2015 on all Climate Change Across Seasons Experiment (CCASE) plots. Reference (or control) plots are shared with the collaborating Northern Forest DroughtNet experiment. There are six plots total (each 11 x 14m). Two are warmed 5 degrees C throughout the growing season (Plots 3 and 4). Two others are warmed 5 degrees C in the growing season and have snow removed during winter to induce soil freeze/thaw cycles (Plots 5 and 6). Four kilometers (2.5 mi) of heating cable are buried in the soil to warm these four plots. Two additional plots serve as controls for our experiment (Plots 1 and 2). Analysis and results from these data are presented in Sanders-DeMott 2018. 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. Sanders-DeMott, R., Sorensen, P.O., Reinmann, A.B. et al. Growing season warming and winter freeze–thaw cycles reduce root nitrogen uptake capacity and increase soil solution nitrogen in a northern forest ecosystem. Biogeochemistry 137, 337–349 (2018). https://doi.org/10.1007/s10533-018-0422-5