Treesearch

Developing rigorous ecological models is a fundamental goal of conservation biologists seeking to forecast biotic responses to climate change. A limitation of many models is they are amechanistic and lack integration of behavior, which is fundamental to animal biology. We integrated biophysical and agent-based models (ABM) to examine how behavior could affect the sensitivity of Plethodontid salamander activity time to climate. Specifically, our model used a temperature differential to stimulate plant climbing, a widely observed behavior among salamanders, which would allow salamanders to...

The loss of Tsuga canadensis from invasion by hemlock woolly adelgid (Adelges tsugae, HWA) has altered ecosystem structure and function in forests across the eastern United States. In southern Appalachian forests, T. canadensis co-occurred with hardwood species and an evergreen Rhododendron maximum shrub layer in riparian and cove positions. In this region, HWA infestation was detected in 2003, with mortality reaching 97% by 2014. In this study we examined responses of light, soil moisture, tree seedling density, and overstory and understory vegetation growth from 2004 to 2014 following...

Estas memorias resumen el resultado de un simposio diseñado para discutir los problemas actuales que confrontan las agencias con responsabilidad para la protección contra incendios forestales a nivel federal y estadual en los EE.UU., al igual que agencias en la comunidad internacional. Los temas discutidos en el simposio incluyen servicios ambientales e incendios forestales: perspectiva nacional e internacional, teoría y modelos para la planificación estratégica de incendios, análisis económico y el manejo integral del fuego, incendios forestales y manejo sustentable de bosques, políticas...

En este trabajo, describimos las actividades internacionales realizadas por la FAO y sus pares a través del tiempo y hacemos una reflexión sobre el rol de las relaciones internacionales en reducir los efectos de los incendios forestales en los servicios ambientales. Por mucho tiempo la FAO ha tenido un enfoque en el manejo de los incendios forestales y ha sido uno de los organismos internacionales en facilitar el desarrollo de un enfoque comprensivo del Manejo Integrado de los Incendios mediante la aplicación de la 5 Rs: Revisión y Análisis, reducción de Riesgo, Preparación (en inglés...

Forests provide significant long-term carbon (C) storage, but have the potential to increase future C emissions with a changing climate. Aboveground biomass, C stores, and the effect of disturbance were examined using forest inventory data collected across all ownerships on 6.2 million ha in Coastal Alaska. We modelled six C pools using empirical data, estimated two others using the literature, and quantified estimate uncertainty. The average (±SE) aboveground live (218.9 ± 4.6 Mg/ha) and log (28.1 ± 1.8 Mg/ha) biomass in the Alaskan Temperate ecoregion were among the lowest in the Pacific...

It is widely known that tropical peatlands, including peat swamp forests (PSFs), provide numerous ecosystem services in both spatial and temporal dimensions. These include their role as large stores for organic carbon, which when not managed well could be released as carbon dioxide and methane, accelerating climate warming. Massive destruction and conversion of peatlands occur at an alarming rate in some regions. We hope that the lessons learned from those regions currently under siege from conversion can inform other regions that are at the precipice of mass conversion to agriculture....

A riverscape perspective considers the ecological and social landscape of the river and its valley. In this context, we examined the spatial arrangement of protective policies for river networks. Riparian land-management standards are policy efforts that explicitly restrict certain management actions, e.g., timber harvest or land clearing, in stream-adjacent lands in order to protect water quality and aquatic habitat. In western Oregon, USA, management standards for riparian lands vary across federal, state, and private landownerships and land uses, projecting a patchwork of protective...

Little is known about the regional extent and variability of nitrate from atmospheric deposition that is transported to streams without biological processing in forests. We measured water chemistry and isotopic tracers (δ18O and δ15N) of nitrate sources across the Northern Forest Region of the USA and Canada and reanalyzed data from other studies to determine when, where, and how unprocessed atmospheric nitrate was transported in catchments. These inputs were more widespread and numerous than commonly recognized, but with high spatial and temporal variability. Only six of 32 streams had...

Forest inventories commonly report fire-adapted pine populations severely reduced from pre-EuroAmerican times due to the combined effects of past land uses and altered fire regimes. Relatively little information exists about the fire ecology and management of hard pine ecosystems in the northeastern U.S. The objective of this study was to determine what burning frequencies best promote regeneration and recruitment of three hard pine species native to the northeastern U.S. We used data from dendrochronological fire history studies to derive historical fire years, pine regeneration years,...

Epidemiological studies consistently show an association between wildfire-related smoke exposure and adverse respiratory health. We conducted a systematic review of evidence in published literature pertaining to heterogeneity of respiratory effects from this exposure in North America. We calculated the within-study ratio of relative risks (RRR) and 95% confidence intervals (CI) to examine heterogeneity of effect by population subgroup, and then summarized the RRRs using meta-analysis. We found evidence of a greater effect of wildfire smoke on respiratory health among females relative to...