Estimating Species Abundance and Basal Area of Oaks in Shenandoah National Park

• Activity Number: 424
• Type: Contributed
• Date/Time: Tuesday, August 11, 2015 : 2:00 PM to 3:50 PM
• Sponsor: Section on Statistics and the Environment
• Author(s): Jing Zhang* and M. Henry H. Stevens
• Companies: Miami University and Miami University
• Keywords: zero-inflated ; count ; semicontinuous ; species abundance ; basal area

Abstract

The objective of Shenandoah National Park Forest Vegetation Monitoring Program is to analyze the sampled vegetation coverage information and obtain the park-wide estimates of tree basal area, density, and abundance. Endpoints observed in the samples include the number of trees of different species in sampled locations (counts) and the corresponding basal areas (continuous measurements). Different Models for the count responses, including Poisson, negative binomial, and zero-inflated Poisson, will be applied to model the observed number of trees. Models that accounts for excessive zeroes in semi-continuous responses, will be applied to analyze the basal area responses.