Treesearch

With the accumulating evidence of changing disturbance regimes becoming increasingly obvious, there is potential for disturbance ecology to become the most valuable lens through which climate-related disturbance events are interpreted. In this paper, I revisit some of the central themes of disturbance ecology and argue that the knowledge established in the field of disturbance ecology continues to be relevant to ecosystem management, even with rapid changes to disturbance regimes and changing disturbance types in local ecosystems. Disturbance ecology has been tremendously successful over...

Prevention activities are actions designed to reduce the likelihood of an ignition in the wildlands or wildland-urban interface (WUI). Excluded are flame spread and firebrand generation processes, and related mitigation approaches, such as fuels management. This section describes preventable wildfire/WUI ignitions, recent ignition patterns over time in the United States, common prevention activities and approaches, methods for measuring the economic performance of prevention activities, recent studies that measured prevention effectiveness, and current measurement challenges.

This is the Preface paper for a special issue of Environmental Pollution that includes ten papers that synthesize cutting-edge studies on: 1) the characteristics of N deposition to global forests, 2) the impacts of N deposition on forest structure and function, 3) the responses of forest ecosystems to regional trends of N deposition and 4) the management options to mitigate negative impacts of N deposition in forest ecosystems. Among the ten papers were reviews on the influence of chronic N deposition on: the structure and function of forest mycorrhizal communities; understory plant...

The objectives of this study were to reconstruct historical fire regime characteristics of red pine (Pinus resinosa) forests in the Adirondack Mountains, and to highlight potential implications for the conservation and preservation of fire-dependent natural communities. Tree-ring dating of dead and living fire-scarred trees at two sites produced records spanning from 1577 to 2015. Historical fire years spanned the years 1693 to 1913 with a concentration of events in the mid-1800s. Fires were primarily low to moderate severity, dormant-season events that were not associated with summer...

The southern pine beetle (SPB) is among the leading biological agents killing southern pine species in the eastern United States. In light of recognized spatiotemporal autocorrelation in SPB outbreaks, we devise a spatiotemporal block bootstrapping method that can be applied to analyze spatiotemporally dependent infestations. We also identify the relevant risk determinants and evaluate their impacts on the frequency of SPB outbreaks. For example, we find forest type, climate, and natural disasters like storm and forest management are all significantly associated with SPB risks. Using the...

Forest resources are critical to environmental, economic, and social development, and there is substantial interest in understanding how global forest area will evolve in the future. Using an Environmental Kuznets Curve (EKC) model of total forest area that we updated using more recent data sets, we projected forest area through 2100 in 168 countries using variables including income, rural population density, and the size of the labor force under different world visions drawn from alternative. Intergovernmental Panel on Climate Change socioeconomic pathways (SSPs). Results provided support...

Planted forests are a rising share of total forests globally and an increasingly important source of timber product output, affecting national and global markets. We estimated econometric models of planted forest area by OECD and non-OECD country groups that control for economic, institutional and environmental policies likely to influence future changes in planted forest area. The models are then used to project planted forest area over next 55 years for 180 countries under five alternative scenarios of global socio-economic changes, represented in shared socioeconomic pathways (SSPs),...

Established illustrations of juvenile wood in pines depict a central core of wood, varying little by diameter or cambial age, to be nested within mature wood tapering to the upper portion of the stem; alternative illustrations show greater complexity in attributing variability within this central core of wood to its proximity to the crown and/or the maturity of the tree when the wood was formed. The present study addresses the degree to which different representations of juvenile wood are applicable to a sampling of 70-yr-old longleaf pine (Pinus palustris Mill.) trees. Wood property maps...

Research Highlights: Two genets of Armillaria altimontana Brazee, B. Ortiz, Banik, and D.L. Lindner and five genets of Armillaria solidipes Peck (as A. ostoyae [Romagnesi] Herink) were identified and spatially mapped within a 16-year-old western white pine (Pinus monticola Doug.) plantation, which demonstrated distinct spatial distribution and interspecific associations. Background and Objectives: A. solidipes and A. altimontana frequently co-occur within inland western regions of the contiguous USA. While A. solidipes is well-known as a virulent primary pathogen that causes root disease...

Drought-related selection during seedling emergence and early development may play a strong role in adaptation. Yet this process is poorly understood and particularly so in relation to ongoing climate change. To evaluate drought-induced differences in selection during early life stages, a total of 50 maternal families sampled from three climatically disparate ponderosa pine (Pinus ponderosa Doug.) populations were grown from seed in two common garden field experiments at a location that was warmer and drier than seed origins. Three drought treatments were imposed experimentally. Phenotypic...