We used Landsat satellite imagery to monitor forest-landscape change within a 4-county area (Angelina, Nacogdoches, San Augustin, and Shelby) in East Texas. We consulted images from the Multispectral Scanner (60-m resolution), Thematic Mapper (30-m resolution), and Thematic Mapper Plus (30-m resolution) from 1974, 1980, 1984, 1987, 1992, 1997, 2002, 2004, 2006, 2007, 2008, and 2009. We classified each image into 1 of 2 land-cover types: forest and non-forest. For data-quality assurance, we assessed 2 of the classified maps for accuracy. We assessed accuracy of the 2002 land-cover map using field validation (overall map accuracy of 98.46%), and the 2009 land-cover map using National Agriculture Imagery Program (NAIP) 2009 aerial photos as a reference (overall map accuracy of 90.77%). To determine forest contagion and fragmentation and their effects on the local landscape, we calculated landscape metrics including PPU (patch per unit) and SqP (square pixel) based on landscape patches identified within each classified map. Results of the 12 classified maps showed a trend of forest-area increase from the 1970s to the early 2000s. Although this East Texas region supports large and small forest stands, we observed habitat fragmentation on non-forest lands; both the total number of patches and total perimeter increased, resulting in smaller patch-size and greater shape complexity on non-forest lands. These changes are influencing timber production and socioeconomic activities in the area, as well as the plant community, wildlife habitat, and water resources of the entire ecosystem.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 15 • No. sp9