Atmospheric Visibility Assessment for Urban Areas Using Photographic Slides and Optical Densitometry (open access)

Atmospheric Visibility Assessment for Urban Areas Using Photographic Slides and Optical Densitometry

The factors involved in calculating Standard Visual Range (SVR) are discussed, and a comparison is made between the visibility reported by airport observers and the photographic slide/ optical densitometer method of calculating SVR. Using slides of Houston, Texas, from the fall and winter of 1988-89, it was found that the altitude at which the contrast measurements are made significantly affects the SVR. Also an index for predicting high and low humidity was developed using the blue/red ratio of the log exposure of the sky, and sun/shade target condition.
Date: May 1992
Creator: Jacob, Mary Katherine
Object Type: Thesis or Dissertation
System: The UNT Digital Library

Ecological Enhancement of Timber Growth: Applying Compost to Loblolly Pine Plantations

Access: Use of this item is restricted to the UNT Community
This study explored the application of compost onto a small loblolly pine tree forest in northeast Texas. Its purpose was to determine if the application of various amounts of compost would provide for accelerated rates of growth for the trees. Soil parameters were also monitored. A total of 270 trees were planted and studied in a northeast Texas forest ecosystem. Compost rates of 5, 25, and 50 tons per acre with either soil or compost backfill were utilized and compared to a control without compost. Nonparametric and parametric ANOVA and Chi-Square tests were utilized. The results indicated that greater application rates retained greater moisture and higher pH levels in the soil. Compost applications also yielded a greater survival rate as well as larger tree height and diameter when compared to the control. The 25 ton/acre application backfilled in native soil achieved the greatest average in height and diameter when compared to the averages for the control plot. Greater growth differences for the 25S application can be attributed to additional nutrients coupled with a stable pH consistent with native soil acidity.
Date: December 1999
Creator: Stuckey, Harold Troy
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Habitat Quantity of Red-Cockaded Woodpecker Picoides Borealis (Aves: Piciformes: Picidae) in its Former Historic Landscape Near the Big Thicket Naitonal Preserve, Texas, USA (open access)

Habitat Quantity of Red-Cockaded Woodpecker Picoides Borealis (Aves: Piciformes: Picidae) in its Former Historic Landscape Near the Big Thicket Naitonal Preserve, Texas, USA

This article quantifies pine-forested habitat suitable for Red-cockaded Woodpecker in the former historic range of the species to assess the potential for possible re-colonization.
Date: January 26, 2016
Creator: Thapa, Vivek & Acevedo, Miguel F.
Object Type: Article
System: The UNT Digital Library