Download or read book Modeling Red Pine Tree Mortality written by Biing Tzuang Guan and published by . This book was released on 1991 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling Red Pine Tree Mortality An Artificial Neural Network Approach written by Biing Tzuang Guan and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of this study is to seek new modeling techniques to improve the ability of projecting tree mortality in forest growth and yield simulation. Multi-layer feed-forward artificial neural networks (ANN) are adopted to achieve the goal. The premise of ANN modeling approach is the ability of such networks to approximate any measurable or continuous function to any desired degree of accuracy, given enough complexity and training. In this study, two types of tree mortality models are developed based on red pine (Pinus resinosa Ait.) data collected from the Great Lakes region. Diameter at breast height (DBH) and annual diameter growth (ADG) are the explanatory variables in both types of models, and annual survival rate is the response variable. For the first type of models, training set consists of data obtained based on a cross-classified scheme. For the second type of models, individual tree records are used to construct training set. Training method for the first type of models is the back-propagation method, and networks are trained on serial computers. A method based on the fast simulated annealing is used to train models of the second, and the trainings are performed on a massively parallel computer. In addition to several goodness-of-fit and performance statistics, a model-based comparison approach is also developed to assess the performance of ANN mortality models against a benchmark statistical model. Results from this dissertation suggest that ANN mortality models not only fit the training data better than the benchmark model, but also expect to perform better in the future, provided that the training set are representative. Model-based comparisons show that ANN mortality model in general have lower prediction biases, but with larger prediction variances, than the benchmark model. Mean squared error criterion suggests that ANN mortality models are expected to perform better in the future, provided the training data are representative. A brief review of modeling tree mortality in forestry growth and yield projection, as well as an overview of neural computing approach, is also presented in this study. Other issues related to the use of artificial neural networks in forestry related modeling are also discussed.

Download or read book Modeling Fire induced Tree Mortality in Longleaf Pine Using Spatial Data written by Holland R. Heese and published by . This book was released on 2014 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: Restoration of fire-excluded pine ecosystems is a major conservation and management goal. Land managers have used prescribed fires to reduce accumulated forest floor fuels and restore pinelands. While these fires have been successful at reducing fuels, tree mortality in these restoration fires can be as high as 75 to 95 percent. In this study, I model post-fire mortality of longleaf pine (in two stands in the Mountain Longleaf National Wildlife Refuge in northeastern Alabama) using logistic models composed of only predictors that can be measured pre-fire. These methods are extended by the addition of spatial competition functions since such measures are drawn from available data for managers, and have been shown to have effects on growth and mortality. The best models, selected by AIC, predict survival as well or better than earlier models but have high false mortality predictions. The spatial dynamics of the stand are also studied pre-fire and post-fire to determine the effect of prescribed fire and inter-tree competition. Post-fire, spatial distribution of the trees did not significantly change. Earlier studies detected differences in the spatial dynamics between different classes of longleaf pine. These dynamics were confirmed in some results and in others questioned. Small trees (DBH 30 cm) clustered away from large trees (DBH 30 cm). Large trees were more dispersed than a random process (Poisson) would dictate. Juveniles (DBH

Download or read book A Competition Process Driven Growth Model for Red Pine written by S. Magnussen and published by . This book was released on 1989 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Description of a simulation model, predicting individual tree growth and mortality using data from a red pine spacing trial. Central elements of the model are changes in relative growth rates as related to changes in tree size, the size of the individual tree relative to the median population size, and the overall stand density. The model parameters are biologically interpretable as measures of the process of competition. Data from 6 spacings were used to develop the model whereas a different data set from 8 spacings served to validate the model. Inclusion of random but correlated error components provided the basis for stochastic simulations. Based on individual stem volume and stand area at age 10 as input, the model was used to predict trends in tree volume distributions until age 35. A detailed graphical representation of model output (summary statistics of stem volume distributions) is presented and compared with observed data.

Download or read book Validation of Two Growth and Yield Models on Red Pine Plantations in Michigan written by Erin E. Smith-Mateja and published by . This book was released on 2003 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Postfire Mortality of Ponderosa Pine and Douglas fir written by James F. Fowler and published by . This book was released on 2004 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: This review focused on the primary literature that described, modeled, or predicted the probability of postfire mortality in ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii). The methods and measurements that were used to predict postfire tree death tended to fall into two general categories: those focusing on measuring important aspects of fire behavior, the indirect but ultimate cause of mortality; and those focusing on tissue damage due to fire, the direct effect of fire on plant organs. Of the methods reviewed in this paper, crown scorch volume was the most effective, easiest to use, and most popular measurement in predicting postfire mortality in both conifer species. In addition to this direct measure of foliage damage, several studies showed the importance and utility of adding a measurement of stem (bole) damage. There is no clear method of choice for this, but direct assessment of cambium condition near the tree base is widely used in Douglas-fir. Only two ponderosa pine studies directly measured fine root biomass changes due to fire, but they did not use these measurements to predict postfire mortality. Indirect measures of fire behavior such as ground char classes may be the most practical choice for measuring root damage. This review did not find clear postfire survivability differences between the two species. The literature also does not show a consistent use of terminology; we propose a standard set of terms and their definitions.

Download or read book Forest Growth and Yield Modeling written by Aaron R. Weiskittel and published by John Wiley & Sons. This book was released on 2011-08-22 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forest Growth and Yield Modeling synthesizes current scientific literature and provides insights in how models are constructed. Giving suggestions for future developments, and outlining keys for successful implementation of models the book provides a thorough and up-to-date, single source reference for students, researchers and practitioners requiring a current digest of research and methods in the field. The book describes current modelling approaches for predicting forest growth and yield and explores the components that comprise the various modelling approaches. It provides the reader with the tools for evaluating and calibrating growth and yield models and outlines the steps necessary for developing a forest growth and yield model. Single source reference providing an evaluation and synthesis of current scientific literature Detailed descriptions of example models Covers statistical techniques used in forest model construction Accessible, reader-friendly style

Download or read book First Order Fire Effects Model written by Elizabeth D. Reinhardt and published by . This book was released on 1997 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: A First Order Fire Effects Model (FOFEM) was developed to predict the direct consequences of prescribed fire and wildfire. FOFEM computes duff and woody fuel consumption, smoke production, and fire-caused tree mortality for most forest and rangeland types in the United States. The model is available as a computer program for PC or Data General computer.

Download or read book A Generalized Forest Growth Projection System Applied to the Lake States Region written by North Central Forest Experiment Station (Saint Paul, Minn.) and published by . This book was released on 1979 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Simulation of an Even aged Red Pine Stand in Northern Minnesota written by Charles Robert Hatch and published by . This book was released on 1971 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Model for Predicting Understory Prescribed Fire Induced Mortality of Red Pine Pinus Resinosa ait written by Derek W. Drake and published by . This book was released on 1995 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Individual tree Probability of Survival Model for the Northeastern United States written by Richard M. Teck and published by . This book was released on 1990 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes a distance-independent individual-tree probability of survival model for the Northeastern United States. Survival is predicted using a six-parameter logistic function with species-specific coefficients. Coefficients are presented for 28 species groups. The model accounts for variability in annual survival due to species, tree size, site quality, and the tree's competitive position within the stand. Model performance is evaluated using the chi-square goodness-of-fit test. Results are presented for the calibration data and an independent validation data set. The model has been incorporated into NE-TWIGS.

Download or read book How to Identify Red Pine Pocket Decline and Mortality written by Kier D. Klepzig and published by . This book was released on 1991 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Probability of Infestation and Extent of Mortality Models for Mountain Pine Beetle in Lodgepole Pine Forests in Colorado written by José F. Negrón and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mountain pine beetle, Dendroctonus ponderosae Hopkins, is a significant agent of tree mortality in lodgepole pine (Pinus contorta Dougl. ex Loud.) forests throughout western North America. A large outbreak of mountain pine beetle caused extensive tree mortality in north-central Colorado beginning in the late 1990s. We use data from a network of plots established in 2006-2007 on the Sulphur Ranger District of the Arapaho and Roosevelt National Forests to develop simple probability of infestation and extent of mortality models using classification and regression trees, respectively. A classification tree indicated that when live lodgepole pine basal area was equal to or greater than 59.3 ft2/acre pre-outbreak, the probability of infestation increased. A second classification tree added lodgepole pine mean diameter as a second splitting variable. The rate of correct classification for both models was greater than 0.79. Two regression trees also used live pre-outbreak lodgepole pine basal area as a splitting variable and indicated increasing basal area killed with increasing live lodgepole pine basal area. These simple models use readily available data from forest inventories and can be used to identify stands, based on forest stand conditions, where mountain pine beetle is more likely to occur and the potential extent of lodgepole pine tree mortality should an outbreak occur.

Download or read book Modeling Individual Tree Mortality of Jack Pine in the Eastern Boreal Forest Ontario Canada written by Ian Christopher Gillies and published by . This book was released on 2005 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Model was developed using sample plot data collected near Longlac in Northwestern Ontario.

Download or read book Modeling the Probability of Individual Tree Mortality written by David Alexander Hamilton and published by . This book was released on 1976 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Case Study Showing Potential Supplies of Red Pine Sawtimber in the Lake States written by Thomas C. Marcin and published by . This book was released on 1975 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: