Treesearch

Carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) are the greenhouse gases largely responsible for anthropogenic climate change. Natural plant and microbial metabolic processes play a major role in the global atmospheric budget of each. We have been studying ecosystem-atmosphere trace gas exchange at a sub-boreal forest in the northeastern United States for over two decades. Historically our emphasis was on turbulent fluxes of CO2 and water vapor. In 2012 we embarked on an expanded campaign to also measure CH4 and N2O. Here we present continuous tower-based measurements of the...

Clifford A. Myers conceived the ponderosa pine growing stock levels (GSL) study in 1961 and completed installation of the study in 1963 in western South Dakota on the Black Hills Experimental Forest (BHEF). The GSL concept was intended to help plan, implement, and illustrate tree thinning strategies (from below) in even-aged stands. A GSL is the suggested tree density (i.e., trees and basal area per acre) based on d.b.h. that can be tended to produce a desired basal area per acre (e.g., 80, 100, 120 square feet) when the mean d.b.h. is 10 inches. Plots representing GSLs 20, 40, 60, 80,...

Old-growth coniferous forests of the Pacific Northwest are among the most productive temperate ecosystems and have the capacity to store large amounts of carbon for multiple centuries. To date, there are considerable gaps in modeling ecosystem fluxes and their responses to physiological constraints in these old-growth forests. These model shortcomings limit our ability to understand and project how the old-growth forests of the Pacific Northwest will respond to global climate change. This study applies the cohort-based Ecosystem Demography Model 2 (ED2) to the Wind River Experimental...

This assessment was conducted to provide information on the current conditions of riparian, wetland, and groundwater-dependent ecosystems in reference to their natural range of variation on the Salmon-Challis National Forest during forest plan revision. We used peer-reviewed literature, data from the Forest and other partners, and site visits to evaluate the status of eight key ecosystem characteristics: (1) distribution and connectivity of riparian ecosystems, (2) distribution of groundwater-dependent ecosystems, (3) surface water and groundwater fluctuations, (4) water quality, (5)...

The common assumption of risk neutrality in forest decision making is generally inadequate because the stakeholderstend to be averse to fluctuations in the return criteria. In Markov decision processes (MDPs) of forest management, risk aversionand standard mean-variance analysis can be readily dealt with if the criteria are undiscounted expected values. However, withdiscounted criteria such as the fundamental net present value of financial returns, the classic mean-variance optimization isnumerically intractable. In lieu of this, this paper (i) presents a linear-programming method to...

Wildland fire and ecological researchers use empirical and semi-empirical modeling systems to assess fire behavior and danger. This technical note describes the firebehavioR package, a porting of two fire behavior modeling systems, Crown Fire Initiation and Spread and a Rothermel-based framework, to the R programming language. We also highlight supporting data objects and functions to predict inputs required for fire behavior estimation. Last, this package contains functions for fifteen indices to express fire danger using weather and/or fuels observations. Specific advantages of predicting...

Before the advent of intensive forest management and fire suppression, western North American forests exhibited a naturally occurring resistance and resilience to wildfires and other disturbances. Resilience, which encompasses resistance, reflects the amount of disruption an ecosystem can withstand before its structure or organization qualitatively shift to a different basin of attraction. In fire-maintained forests, resilience to disturbance events arose primarily from vegetation pattern-disturbance process interactions at several levels of organization. Using evidence from 15 ecoregions,...

Wind and weather in mountainous areas are complex because of the underlying terrain. Typically, regional computer models are needed with sufficiently high resolution to resolve such complex conditions. However, this high-resolution weather information usually becomes available only when the critical time in fighting a severe fire event is long past, thus the advantage of using high-resolution weather models for fire management seems limited. To address this problem, we have developed an experimental system called FireBuster that is designed to streamline and automate many intermediate...

Futures research is a transdisciplinary field of inquiry that uses a variety of methods to explore possible, plausible, and preferable futures. The goal is to develop foresight—insight into how and why the future could be different than today—to improve policy, planning, and decision making. Scores of futures research methods have been developed or adapted from other disciplines, beginning with pioneering work in the US military and RAND Corporation in the 1950s and 1960s. But many social scientists and natural resource professionals are unaware of these methods and most have never heard...

Emerald ash borer (EAB; Agrilus planipennis Fairmaire, 1888) has been a persistent disturbance for ash forests in the United States since 2002. Of particular concern is the impact that EAB will have on the ecosystem functioning of wetlands dominated by black ash (Fraxinus nigra Marsh.). In preparation, forest managers need reliable and complete maps of black ash dominated stands. Traditionally, forest survey data from the United States Forest Inventory and Analysis (FIA) Program have provided rigorous measures of tree species at large spatial extents but are limited when providing estimates...