Title: Building improved models of sugar maple mortality
Author: Perry, Charles H.; Zimmerman, Patrick L.;
Source: In: Morin, Randall S.; Liknes, Greg C., comps. Moving from status to trends: Forest Inventory and Analysis (FIA) symposium 2012; 2012 December 4-6; Baltimore, MD. Gen. Tech. Rep. NRS-P-105. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. [CD-ROM]: 204-209.
Publication Series: Paper (invited, offered, keynote)
Description: The decline of sugar maple (Acer saccharum Marsh.) in the northern United States is causing concern, and several studies have identified soil properties that are linked to the observation of dead/dying trees. Unfortunately, the sample of trees supporting these studies is purposive in nature; soil properties are assessed only on those plots where dead trees are observed. In this study, we used the U.S. Forest Service's Forest Inventory and Analysis database (FIADB) to conduct an exploratory analysis of a broader population of sugar maple (live and dead) across a wide range of soil types. This population of plots has a highly skewed, zero-inflated distribution: the number of plots in the sample without dead trees is an order of magnitude greater than the number of plots with dead trees. One effective method of analysis is a hurdle--or conditional--model approach. In the first phase, the response variable is the presence or absence of dead sugar maple and the inferential space is the entire population of plots with sugar maple trees. The second phase uses the relative abundance of dead sugar maple as the response variable; in this case, inference is restricted to those plots where dead sugar maple trees are observed. In both sets of models, basal area and geology are significant predictors of dead sugar maple, but the most significant soil variables vary between these two inferential spaces. Our study highlights important analytical considerations when using FIADB for analysis of forest health conditions and presents simple methods to create a more comprehensive space for statistical inference.
Keywords: statistics, estimation, sampling, modeling, remote sensing, forest health, data integrity, environmental monitoring, cover estimation, international forest monitoring
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
- This publication may be available in hard copy. Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact Sharon Hobrla, firstname.lastname@example.org if you notice any errors which make this publication unusable.
XML: View XML
Perry, Charles H.; Zimmerman, Patrick L. 2012. Building improved models of sugar maple mortality. In: Morin, Randall S.; Liknes, Greg C., comps. Moving from status to trends: Forest Inventory and Analysis (FIA) symposium 2012; 2012 December 4-6; Baltimore, MD. Gen. Tech. Rep. NRS-P-105. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. [CD-ROM]: 204-209.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility