Treesearch

The direct multiangle solution may allow inversion of the scanning lidar data even when the requirement of the horizontally stratified atmosphere is poorly met. The solution is based on two principles: (1) The signal measured in zenith is the core source for extracting the information about the atmospheric aerosol loading, and (2) The multiangle signals are used as auxiliary data to extract the vertical transmittance profile from the zenith signal. However, there may exist a level of horizontal heterogeneity of the atmosphere when no reliable information about the optical properties can be...

An expansive mountain pine beetle (MPB) epidemic is currently impacting North American forests (Raffa et al. 2008). As beetle-attacked trees die, lose their needles, and eventually fall to the ground, there are substantial changes in stand structure. These fuel changes likely affect both surface and crown fire behavior, but there is not yet a consensus among experts regarding the nature and magnitude of these effects (Jenkins et al. 2008). Simard et al. (2011; hereafter referred to as SRGT) used linked crown fire models implemented in the NEXUS crown fire modeling system (Scott and...

Wildland managers need detailed information about the responses of invasive species to fire and the conditions that increase site invasibility in order to effectively manage fire without introducing or increasing populations of invasive plants. Literature reviews and syntheses of original research are important sources of this information, but the usefulness of a review is limited by the quantity, quality, and geographic coverage of information available when it is written. This study analyzed the information available for 61 syntheses published in the Fire Effects Information System...

The Sierra Ancha International Cooperative Program on Assessment and Monitoring of Air Pollution Effects on Forests study site or (SAEF-ICP II) is part of an international network of cooperative forest monitoring sites spread throughout Europe and the United States. The United Nations Economic Commission for Europe established the ICP II network in 1985 to monitor long-term effects of transboundary air pollution. The Sierra Ancha Experimental Forest was chosen to be a part the U.S.'s network because it is the southernmost Experimental Forest in the contiguous U.S., and because it is...

Fire and fuels management have become increasingly challenging in the last three decades due to climate change, invasive species, urbanization and development, increased land use, and the effects of these factors on fire size and frequency (Westerling et al. 2007; D’Antonio and Vitousek 1992). Often, the science and information needed to carry out best management practices are lacking or difficult to find (Simpson 2009; Wright 2004). Fires do not stop burning at jurisdictional boundaries, and land managers must work with the complexities of differing agency missions, policies, resource...

In 2009, the federal Joint Fire Science Program (JFSP) initiated a national network of boundary organizations, known as regional fire science consortia, to accelerate the awareness, understanding, and use of wildland fire science. Needs assessments conducted by consortia in eight regions of the United States are synthesized here using a case survey approach. Although regions used different methods based on their different ecosystems, geography, and demography, results showed striking similarities in how fire science is accessed and used, barriers to its use, and research information...

Coastal communities in the southeast United States have regularly experienced severe hurricane impacts. To better facilitate recovery efforts in these communities following natural disasters, state and federal agencies must respond quickly with information regarding the extent and severity of hurricane damage and the amount of tree debris volume. A tool was developed to detect downed trees and debris volume to better aid disaster response efforts and tree debris removal. The tool estimates downed tree debris volume in hurricane affected urban areas using a Leica Airborne Digital Sensor...

Animals select habitat resources at multiple spatial scales; therefore, explicit attention to scale-dependency when modeling habitat relations is critical to understanding how organisms select habitat in complex landscapes. Models that evaluate habitat variables calculated at a single spatial scale (e.g., patch, home range) fail to account for the effects of other scales on the probability of species occurrence. Although single-scale approaches are common, we hypothesize that such models will be less predictive and incur greater risk of false inferences than multiscale models that account...

Non-native invasive plants (NNIP) are rapidly spreading into natural ecosystems such as forests in the Upper Midwest. Using the strategic inventory data from the 2005-2006 U.S. Department of Agriculture, Forest Service’s Forest Inventory and Analysis (FIA) program and forest land cover data, we estimated the regional-invasibility patterns of NNIPs for major forest types by using Geographic Information Systems (GIS) and geostatistical tools. We define the regional invasibility of a forest ecosystem as its susceptibility to the colonization and establishment of NNIPs, measured by a function...