Skip to main content
Advanced Search

Filters: Tags: forests (X) > Categories: Publication (X) > partyWithName: Northeast CSC (X)

15 results (75ms)   

View Results as: JSON ATOM CSV
Concern over global environmental change and associated uncertainty has given rise to greater emphasis on fostering resilience through forest management. We examined the impact of standard silvicultural systems (including clearcutting, shelterwood, and selection) compared with unharvested controls on tree functional identity and functional diversity in three forest types distributed across the northeastern United States. Sites included the Argonne, Bartlett, and Penobscot Experimental Forests located in Wisconsin, New Hampshire, and Maine, respectively. We quantified functional trait means for leaf mass per area, specific gravity, maximum height, height achieved at 20 years, seed mass, drought tolerance, shade tolerance,...
Abstract (from https://link.springer.com/article/10.1007/s10980-017-0540-9): Context Quantitative models of forest dynamics have followed a progression toward methods with increased detail, complexity, and spatial extent. Objectives We highlight milestones in the development of forest dynamics models and identify future research and application opportunities. Methods We reviewed milestones in the evolution of forest dynamics models from the 1930s to the present with emphasis on forest growth and yield models and forest landscape models We combined past trends with emerging issues to identify future needs. Results Historically, capacity to model forest dynamics at tree, stand, and landscape scales was constrained...
Categories: Publication; Types: Citation; Tags: Forests, Landscapes, Northeast CASC
Abstract (from http://link.springer.com/article/10.1007%2Fs10980-015-0294-1): Context Tree species distribution and abundance are affected by forces operating at multiple scales. Niche and biophysical process models have been commonly used to predict climate change effects at regional scales, however, these models have limited capability to include site-scale population dynamics and landscape-scale disturbance and dispersal. We applied a landscape modeling approach that incorporated three levels of spatial hierarchy (pixel, landtype, and ecological subsection) to model regional-scale shifts in forest composition under climate change. Objective To determine (1) how importance value of individual species will...
Abstract (from: http://link.springer.com/article/10.1007/s00442-014-2881-2): Forest biomass growth is almost universally assumed to peak early in stand development, near canopy closure, after which it will plateau or decline. The chronosequence and plot remeasurement approaches used to establish the decline pattern suffer from limitations and coarse temporal detail. We combined annual tree ring measurements and mortality models to address two questions: first, how do assumptions about tree growth and mortality influence reconstructions of biomass growth? Second, under what circumstances does biomass production follow the model that peaks early, then declines? We integrated three stochastic mortality models with...
Eastern spruce-fir forest ecosystems are among the most vulnerable to climate change within the conterminous US. The goal of this project was to develop tools to identify refugia sites most likely to support spruce-fir forest and its associated high-priority obligate spruce-fir bird species over the long-term under projected climate change scenarios. Specific research objectives included: (1) producing high-resolution (temporal and spatial) projections of spruce-fir forests, including stand characteristics like structure and composition; (2) estimating future changes in the distribution, productivity, and stand characteristics of the spruce-fir forest type due to potential changes in climate; (3) comparing the distribution...
Abstract (from http://link.springer.com/article/10.1007%2Fs10980-015-0217-1): Context Tree species distribution and abundance are affected by forces operating across a hierarchy of ecological scales. Process and species distribution models have been developed emphasizing forces at different scales. Understanding model agreement across hierarchical scales provides perspective on prediction uncertainty and ultimately enables policy makers and managers to make better decisions. Objective Our objective was to test the hypothesis that agreement between process and species distribution models varies by hierarchical level. Due to the top-down approach of species distribution models and the bottom-up approach of process...
Forests in the Eastern United States are changing in response to ecological succession, tree harvest and other disturbances and climate change has the potential to further change these forests. We predicted the distribution and abundance of common tree species across portions of the Eastern U.S. under alternative climate scenarios that varied in the amount of warming by the end of the century from 1.1 to 4.2 degrees C. We used a forest landscape change model to forecast changes in tree abundances and distribution in the North Atlantic region of the U.S. while accounting for climate change, succession, and harvest. We then considered a broader region of the U.S. and combined our results with results from previous...
Abstract (from http://www.sciencedirect.com/science/article/pii/S1146609X15300059): Woody species are increasing in density, causing transition to more densely wooded vegetation states, and encroaching across ecotonal borders into non-forested ecosystems. We examined USDA Forest Service Forest Inventory and Analysis data to identify tree species that have expanded longitudinally in range, particularly into the central United States. We analyzed compositional differences within ecological regions (i.e., subsections) in eastern and western ranges of species using repeated measures ANOVA. We considered differences in outer ranges to indicate range expansion or contraction. We also estimated the shift in forest area...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1111/gcb.13046/abstract): Ecotones are transition zones that form, in forests, where distinct forest types meet across a climatic gradient. In mountains, ecotones are compressed and act as potential harbingers of species shifts that accompany climate change. As the climate warms in New England, USA, high-elevation boreal forests are expected to recede upslope, with northern hardwood species moving up behind. Yet recent empirical studies present conflicting findings on this dynamic, reporting both rapid upward ecotonal shifts and concurrent increases in boreal species within the region. These discrepancies may result from the limited spatial extent of observations....
Abstract (from http://www.sciencedirect.com/science/article/pii/S1364815215300621): Process-based forest ecosystem models vary from simple physiological, complex physiological, to hybrid empirical-physiological models. Previous studies indicate that complex models provide the best prediction at plot scale with a temporal extent of less than 10 years, however, it is largely untested as to whether complex models outperform the other two types of models at plot and regional scale in longer timeframe (i.e. decades). We compared model predictions of aboveground carbon by one representative model of each model type (PnET-II, ED2 and LINKAGES v2.2, respectively) with field data (19–77 years) at both scales in the Central...
Abstract (from https://link.springer.com/article/10.1007/s10980-016-0429-z): Context Forests in the northeastern United States are currently in early- and mid-successional stages recovering from historical land use. Climate change will affect forest distribution and structure and have important implications for biodiversity, carbon dynamics, and human well-being. Objective We addressed how aboveground biomass (AGB) and tree species distribution changed under multiple climate change scenarios (PCM B1, CGCM A2, and GFDL A1FI) in northeastern forests. Methods We used the LANDIS PRO forest landscape model to simulate forest succession and tree harvest under current climate and three climate change scenarios from...
Categories: Publication; Types: Citation; Tags: Forests, Landscapes, Northeast CASC
Abstract (from https://link.springer.com/article/10.1007/s10980-016-0473-8): Context Global climate change impacts forest growth and methods of modeling those impacts at the landscape scale are needed to forecast future forest species composition change and abundance. Changes in forest landscapes will affect ecosystem processes and services such as succession and disturbance, wildlife habitat, and production of forest products at regional, landscape and global scales. Objectives LINKAGES 2.2 was revised to create LINKAGES 3.0 and used it to evaluate tree species growth potential and total biomass production under alternative climate scenarios. This information is needed to understand species potential under...
Categories: Publication; Types: Citation; Tags: Forests, Landscapes, Northeast CASC
Abstract (from ScienceDirect): Maximum stand density index (SDImax) is an important factor controlling stand dynamics that varies by species and region, but less is understood how it differs within a region for a given species. In this analysis, linear quantile mixed modeling (LQMM) and an extensive network of permanent plots were utilized to examine regional variation in the SDImax of 15 species (7 softwoods and 8 hardwoods) across the complex forests of the Acadian Region in North America. Observed plot-level SDImax was then linked to various stand, plant trait, site, and climatic factors and the spatial patterns throughout the region examined. Results indicated high variability of SDImax for a given species with...
Abstract (from http://www.sciencedirect.com/science/article/pii/S0378112714003028): Plant functional traits (PFTs) have increased in popularity in recent years to describe various ecosystems and biological phenomena while advancing general ecological principles. To date, few have investigated distributional attributes of individual PFTs and their relationship with key attributes and processes of forest ecosystems. The objective of this study was to quantify the distribution and contribution of various PFTs in determining forest structure, live tree production (volume and biomass), and tree mortality across the eastern US. In total, 16 metrics representing species specific gravity and their shade, flood, and drought...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1890/ES15-00238.1/abstract): Most temperate forests in U.S. are recovering from heavy exploitation and are in intermediate successional stages where partial tree harvest is the primary disturbance. Changes in regional forest composition in response to climate change are often predicted for plant functional types using biophysical process models. These models usually simplify the simulation of succession and harvest and may not consider important species-specific demographic processes driving forests changes. We determined the relative importance of succession, harvest, and climate change to forest composition changes in a 125-million ha area of the Central Hardwood...