Geology topics

Darrell E. Napton

Publications and source records attributed to Darrell E. Napton.

5 recordsLinked to original sources

USGS2019

The driving forces of land change in the Northern Piedmont of the United States

Driving forces facilitate or inhibit land-use/land-cover change. Human driving forces include political, economic, cultural, and social attributes that often change across time and space. Remotely sensed imagery provides regional land-change data for the Northern Piedmont, an ecoregion of the United States that continued to urbanize after 1970 through conversion of agricultural and forest land covers to developed uses. Eight major driving forces facilitated most of the land conversion; other drivers inhibited or slowed change. A synergistic web of drivers may be more important in understanding land change than individual drivers by themselves.

Maryl;New York;Pennsylvania;Virginia↗

USGS2015

The Southern Piedmont’s continued land-use evolution, 1973–2011

The southern Piedmont in the U.S. was an important farming region during the 19 th century, but by the end of the 20th century, agricultural land use had decreased substantially with forest becoming the majority land cover by the 1970s. Geographical literature has documented this change but has not concentrated on the region’s contemporary land uses. The Piedmont currently has three main types of land use and land cover changes: cyclic forestry, changes between forest and agriculture, and urbanization. The first and second groupings are reversible and land uses and land covers can change among them, but urbanization is normally a permanent change that increases in area through time. U.S. Geological Survey findings indicate that cyclic forestry of cutting (clearing) and regrowth dominated recent land change in the Piedmont. This paper explores the Piedmont’s current land uses and some of their driving forces.

Alabama, Georgia, North Carolina, South Carolina, ↗

USGS2012

Southern and Central California Chaparral and Oak Woodlands Ecoregion: Chapter 19 in Status and trends of land change in the Western United States--1973 to 2000

The Southern and Central California Chaparral and Oak Woodlands Ecoregion, which covers approximately 102,110 km 2 (39,425 mi 2 ), is characterized by a Mediterranean climate with cool, moist winters and hot, dry summers (Omernik, 1987; U.S. Environmental Protection Agency, 1997). Natural vegetation includes chaparral (for example, manzanita, Arctostaphylos spp.) and oak ( Quercus spp.) woodlands with extensive grassland and shrubland cover. The low mountains and foothills of the ecoregion border or parallel the Pacific Ocean from Mexico to Point Reyes, California, and continue inland surrounding the Central California Valley Ecoregion (fig. 1). These mountains and hills are interrupted by limited areas of flat land generally used for development or agriculture. The largest developed area in the ecoregion is the Los Angeles Basin, followed by the San Francisco Bay area and the San Diego metropolitan area (fig. 1). The largest agricultural area is the Salinas River valley south of Monterey, California. Most of the ecoregion consists of rangelands classified as grassland/ shrubland and forest land covers (figs. 1,2).

California↗

USGS2009

Land changes and their driving forces in the Southeastern United States

The ecoregions of the Middle Atlantic Coastal Plain, Southeastern Plains, Piedmont, and Blue Ridge provide a continuum of land cover from the Atlantic Ocean to the highest mountains in the East. From 1973 to 2000, each ecoregion had a unique mosaic of land covers and land cover changes. The forests of the Blue Ridge Mountains provided amenity lands. The Piedmont forested area declined, while the developed area increased. The Southeastern Plains became a commercial forest region, and most agricultural lands that changed became forested. Forests in the Middle Atlantic Coastal Plain declined, and development related to recreation and retirement increased. The most important drivers of land conversion were associated with commercial forestry, competition between forest and agriculture, and economic and population growth. These and other drivers were modified by each ecoregion’s unique suitability and land use legacies with the result that the same drivers often produced different land changes in different ecoregions.

Regional Environmental Change↗

USGS2000

The land cover trends project: A strategy for monitoring land cover change at a national scale

Policy-makers and scientists often require comprehensive data on the types and rates of land use and land cover change at a variety of scales. However, there is generally a lack of local, regional, and national land use and land cover data of sufficient reliability and temporal and geographic detail for providing accurate estimates of landscape change. The U.S. Geological Survey's EROS Data Center and the Landscape Ecology Branch of the U.S. Environmental Protection Agency are collaborating on a four-year research project to document the types, distributions, rates, drivers, and consequences of land cover change for the conterminous United States over the past 30 years. The project is using an ecoregion framework as a geographic stratifier. Both regional and national characteristics of change are determined by sampling land cover change for each of 84 ecoregions using five selected epochs of data from the nearly 30-year record of Landsat 1-7 data. Three types of land cover variables are being mapped or derived: (1) general land cover type; (2) landscape biophysical properties; and (3) landscape pattern. Assessments of the drivers and consequences of change within each ecoregion are then prepared. A pilot phase focusing on the analysis of five selected ecoregions is well underway and will be completed by the end of 2000. Methodologies established during the pilot phase will then be applied to the remaining ecoregions.

Conference Paper↗