Treesearch

There is increasing momentum to implement conservation and management approaches that adapt forests to climate change so as to sustain ecosystem functions. These range from actions designed to increase the resistance of current composition and structure to negative impacts to those designed to transition forests to substantially different characteristics. A component of many adaptation approaches will likely include assisted migration of future climate-adapted tree species or genotypes. While forest-assisted migration (FAM) has been discussed conceptually and examined experimentally for...

Uncertainty and emerging threats associated with climate change necessitate the development of new approaches for managing forest ecosystems. To address this need the Adaptive Silviculture for Climate Change (ASCC) Network was established to examine the efficacy of three climate adaptation strategies in important forest types across North America: 1) resistance to change by increasing overstory tree health through reduced inter-tree competition, 2) resilience by creating conditions that allow change within the natural range of variability while encouraging greater abundance of native...

Black ash (Fraxinus nigra Marsh.) forests of north-central North America are currently threatened by the non-native emerald ash borer (Agrilus planipennis, EAB). Despite the wide distribution of F. nigra ecosystems, and the concern over EAB impact, little is known about their structure and natural stand dynamics. We sampled six old-growth F. nigra stands to assess structure, composition, tree recruitment, and past disturbance. Dendrochronological results revealed that disturbance rates fluctuated markedly over the past 200 years or more, but remained relatively low, suggesting small- to...

We consider how the stoichiometry and energy content of organic matter reservoirs and fluxes through and from a peatland enable the fluxes and storage of carbon within a peatland to be constrained. We include the elemental composition of the above- and below-ground biomass, litter, the peat profile, and the dissolved and particulate organic matter within a blanket bog in northern England for which the C budget has previously been measured. The study shows, based only on the elemental composition, and calculation of oxidation and energy contents, that: (a) Dissolved organic carbon (DOC) in...

This report provides a look at changes that could come to pass and impact recreation on public lands over the next 30 years. The data were over 700 horizon scan hits from our Forest Futures Horizon Scanning Project. Horizon scan hits are a useful early warning system. Horizon scan hits may be directly related to outdoor recreation (e.g., the decline of snow fall) or they may be indirectly related (e.g., the development of lab-grown meat). Because weak signals of change are as important as strong signals, a single scan hit is worthy of consideration, even if it stands alone. These horizon...

A lone shortleaf pine stands nearly 100 feet tall, rooted in the stony soils of a cliff, overlooking a valley. Protected by its thick bark, the pine has survived a long history of frequent fires set by Osage Indians and Scotch-Irish immigrants. It escaped the woodsman's axe by its remote location. Over its 350 years of life, it has seen dramatic changes from the days when the Osage people plied the waters of the river below in their canoes. It stood through the agricultural and industrial revolutions that swept through the Missouri Ozarks in the later 19th and early 20th centuries. Today,...

Background. Media wildfire coverage can shape public knowledge on fire-related issues, and potentially influence management decisions, so understanding the content of its coverage is important. Previous research examining media wildfire coverage has primarily focused on either a single fire or issue, and provides little insight about the range of wildfire-related topics discussed in the media. Aims. We aimed to assess wildfire topics covered in print media between 1986 and 2016 across the USA, Canada and Australia. Methods. Machine learning-based automated content analyses were conducted...

Estimating forest aboveground biomass (AGB) at large scales and fine spatial resolutions has become increasingly important for greenhouse gas accounting, monitoring, and verification efforts to mitigate climate change. Airborne LiDAR is highly valuable for modeling attributes of forest structure including AGB, yet most LiDAR collections take place at local or regional scales covering irregular, non-contiguous footprints, resulting in a patchwork of different landscape segments at various points in time. Here, as part of a statewide forest carbon assessment for New York State (USA), we...

The Forest Inventory and Analysis (FIA) program of the Forest Service, an Agency of the U.S. Department of Agriculture, provides what is arguably the most valuable forest resource dataset in the United States. These data are the basis for numerous inquiries across a wide range of forest-related attributes at various spatial and temporal scales. While user-friendly analytical tools are publicly available to facilitate the use of the data without expert knowledge, there is a need for detailed documentation of the underlying sampling and estimation procedures. The audience for this information...

Tree-derived dissolved organic matter (DOM) comprises a significant carbon flux within forested watersheds. Few studies have assessed the optical properties of tree-derived DOM. To increase understanding of the factors controlling tree-derived DOM quality, we measured DOM optical properties, dissolved organic carbon (DOC) and calcium concentrations in throughfall and stemflow for 17 individual rain events during summer and fall in a temperate deciduous forest in Vermont, United States. DOC and calcium fluxes in throughfall and stemflow were enriched on average 4 to 70 times incident fluxes...