Treesearch

Understanding and modeling land cover and land use change is evolving into a foundational element of climate, environmental, and sustainability science. Land cover and land use data are core to applications such as carbon accounting, greenhouse gas emissions reporting, biomass and bioenergy assessments, hydrologic function assessments, fire and fuels planning and management, and forest and rangeland health assessments. Remote sensing-based monitoring efforts like the North American Forest Dynamics (NAFD) project, and the newly launched Landscape Change Monitoring System (LCMS), will...

During the past 2 decades, the forests of the Interior West of the United States have been impacted by drought, insects, disease, and fire. When considered over periods of 5-10 years, many forest types have experienced periods of negative net growth, meaning that mortality exceeded gross growth at the population scale. While many of these changes have been attributed almost solely to climate change, the factors contributing to widespread mortality, and their interactions, are much more complex. For example, the dominant forest age class distribution, in which a high percentage of acreage...

Each of the U.S. Forest Service’s Forest Inventory and Analysis (FIA) regions has an occasional need to intensify the national sampling grid. A variety of methodologies exist within the various FIA regions and National Forest Systems regions for constructing plot intensifications, and there is no consensus on a national procedure The primary objectives of this paper were to identify various intensification methods being implemented by FIA or used by other groups, examine their advantages and disadvantages for establishing intensified plots within the existing FIA framework, and recommend a...

In the late 1860s, Euro-American settlement and related activities, including logging, began affecting the composition and structure of forests of the western United States. These impacts were likely to be most substantial along the corridor of the trans-continental railroad. Construction and maintenance of the railroad created a high dependence for wood, especially the cutting of lodgepole pine forests for railroad ties (known as tie hacking). Although some of the impact has been documented, the amount of ecosystem change in lodgepole pine forests is not well known. In this study we...

The authors are developing a REDD+ MRV system that tests different biomass estimation frameworks and components. Design-based inference from a costly fi eld plot network was compared to sampling with LiDAR strips and a smaller set of plots in combination with Landsat for disturbance monitoring. Biomass estimation uncertainties associated with these different data sets in a design-based inference framework was examined. The authors are also testing estimators that rely primarily on Landsat within a model-based inference framework. Contributions from Landsat are current (e.g., 2013) spectral...

In 2009, the Interior West Forest Inventory and Analysis (FIA) program of the U.S. Forest Service started to archive approximately 11 000 increment cores collected in the Interior West states during the periodic inventories of the 1980s and 1990s. The two primary goals for use of the data were to provide a plot-linked database of radial growth to be used for growth model development and other biometric analyses, and to develop a gridded dendroecological database that could be used to analyze regional patterns of climate, disturbance, and other ecosystem-scale processes. Early analysis...

Random forests (RF) and stochastic gradient boosting (SGB), both involving an ensemble of classification and regression trees, are compared for modeling tree canopy cover for the 2011 National Land Cover Database (NLCD). The objectives of this study were twofold. First, sensitivity of RF and SGB to choices in tuning parameters was explored. Second, performance of the two final models was compared by assessing the importance of, and interaction between, predictor variables, the global accuracy metrics derived from an independent test set, and the visual quality of the resultant maps of tree...

Next-generation sequencing (NGS) has revolutionized the field of genetics by providing a means for fast and relatively affordable sequencing. With the advancement of NGS, wholegenome sequencing (WGS) has become more commonplace. However, sequencing an entire genome is still not cost effective or even beneficial in all cases. In studies that do not require a whole-genome survey, WGS yields lower sequencing depth and sequencing of uninformative loci. Targeted sequencing utilizes the speed and low cost of NGS while providing deeper coverage for desired loci. This thesis applies targeted...

Fungi in the genus Armillaria are associated with an important disease of deciduous and coniferous trees and shrubs in western North America. This study examined the distribution of Armillaria by forest habitat types on the Kaibab National Forest and northern Coconino National Forest, Arizona. Over 400 trees were examined for Armillaria in 76 Interior West Forest Inventory and Analysis permanent plots representing 17 different habitat types. Samples of the fungus associated with Armillaria root disease were collected from 23 trees and identified using DNA sequencing. All samples were...

Dispersal is a key process influencing population dynamics and gene flow in species. Despite this, little is known about breeding dispersal in threatened Mexican Spotted Owls (Strix occidentalis lucida), here defined as movement of a non-juvenile owl between territories where it had the opportunity to breed. We observed 28 cases of breeding dispersal during a study of color-banded Mexican Spotted Owls in the Sacramento Mountains, New Mexico, 2003-2011. This represented 4.9% of total opportunities to disperse (n = 575 observed occasions, range = 0-9.0% of owls dispersing per yr). Breeding...