Treesearch

The effects of field plot configurations on the uncertainties of plot-level forest resource estimates were analyzed using airborne laser scanner data, aerial photographs and field measurements. The aim was to select a field sample plot configuration that can be used for both large area and management inventories. Error estimates were evaluated at the plot level using six different training plot configurations. Additionally, separate plots with two different sizes were used for evaluation. Stem volume and five other forest resource characteristics were considered. The field measurement...

The importance of forests for satisfying social, economic, and ecological demands continues to increase. National Forest Inventories (NFIs) are the main tool for responding to the information requests related to these demands. National and international reporting obligations mirror these needs for information, but due to a lack of political coordination, NFIs use a huge variety of data collection protocols and reporting formats including non-matching terms and definitions. These circumstances characterize the challenges linked to international information requests for estimates of future...

The spatial patterns resulting from large fires include refugial habitats that support surviving legacies and promote ecosystem recovery. To better understand the diverse ecological functions of refugia on burn mosaics, we used remotely sensed data to quantify neighborhood patterns of areas relatively unchanged following the 2011 Las Conchas fire. Spatial patterns of refugia measured within 10-ha moving windows varied across a gradient from areas of high density, clustered in space, to sparsely populated neighborhoods that occurred in the background matrix. The scaling of these patterns...

Assessment of pre-harvest stand conditions after unplanned tree removals often requires reconstruction of the stand based on stump information. Prediction of diameter at breast height (d.b.h.) from stump measurements is a common practice because d.b.h. is usually a necessary precursor for estimating diameter distributions and predicting tree volume. Although not a widespread exercise, tree volumes are sometimes predicted directly from stump dimensions. Regardless of the approach taken, statistical models are invariably used in some manner and the model predictions are erroneously assumed...

The conservation of biological diversity is recognized as a fundamental component of sustainable devel-opment, and forests contribute greatly to its preservation. Structural complexity increases the potentialbiological diversity of a forest by creating multiple niches that can host a wide variety of species. To facilitate greater understanding of the contributions of forest structure to forest biological diversity, we modeled relationships between 14 forest structure variables and airborne laser scanning (ALS) data for two Italian study areas representing two common Mediterranean forests,...

Organizational hierarchy is an inescapable aspect of many exemplary high reliability organizations (HROs). As organizations begin to adopt HRO theorizing to improve practice, it is increasingly important to explain how HRO principles - which assume the hallmarks of a flat hierarchy - can be understood and enacted in rigidly stratified organizations. We propose a preliminary theoretical model suggesting how various supervisor - subordinate and work group communication patterns and practices enable members to navigate hierarchy to achieve high reliability. We test the model using structural...

We are in the midst of a wave of 50th anniversaries. Specifically, the wave consists of 50th anniversaries for legislative milestones in the United States. That’s because the 1960s were a time of profound social and environmental change. The Civil Rights Act, the Wilderness Act, and the Land and Water Conservation Fund Act were all enacted in 1964. The Voting Rights Act was passed in 1965. The National Historic Preservation Act was in 1966, and the Wild and Scenic Rivers Act of 1968 was signed into law on the same day as the National Trails System Act. Other groundbreaking legislation will...

International organizations increasingly require estimates of forest parameters to monitor the state of and changes in forest resources, the sustainability of forest practices and the role of forests in the carbon cycle. Most countries rely on data from their national forest inventories (NFI) to produce these estimates. However, because NFI survey years may not match the required reporting years, techniques for updating NFI-based estimates are necessary. The main aim was to develop an unbiased method to update NFI estimates of mean growing stock volume (m3/ha) using models to predict...

One of many possible climate change effects in temperate areas is the increase of frequency and severity of windstorms; thus, fast and cost efficient new methods are needed to evaluate wind-induced damages in forests. We present a method for assessing windstorm damages in forest landscapes based on a two-stage sampling strategy using single-date, post-event airborne laser scanning (ALS) data. ALS data are used for delineating damaged forest stands and for an initial evaluation of the volume of fallen trees. The total volume of fallen trees is then estimated using a two-stage model-assisted...

One of the benefits of model-based inference relative to design-based inference is that probability samples are not required which means that models can be constructed using data external to the area of interest. Although "external" usually means spatially or geographically external, it could also be used in the temporal sense that the model is constructed using data whose dates are temporally external to the dates of the data to which the model is applied. This study focuses on assessing the effects of such temporally external application data on model-based inference using remotely...