Publications

The knowledge of net primary production (NPP) dynamics at regional scale will help to understand terrestrial carbon cycling, especially with respect to land use and global climate change. Guangdong province has high plant growth potential because of plenty of light, heat, and water resources in this region. Forest coverage increased significantly from less than 30% in the early l980s to

The U.S. Geological Survey (USGS) proposes six strategic directions for managing ecosystems along with modernization of observation networks of land, water, and biological resources.

The U.S. Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS) maintains a wide variety of remotely sensed data collections that contain a wealth of information about the Earth’s land surfaces. Acquired by special sensors carried aboard civilian satellites and aircraft, the images and other data in these collections provide a unique perspective of the...

No abstract available.

The Landsat-5 (L5) satellite was launched on March 01, 1984, with a design life of three years. Incredibly, the L5 Thematic Mapper (TM) has collected data for 23 years. Over this time, the detectors have aged, and its radiometric characteristics have changed since launch. The calibration procedures and parameters have also changed with time. Revised radiometric calibrations have improved...

In February 2000, the Shuttle Radar Topography Mission (SRTM) successfully collected Interferometric C-Band Synthetic Aperture Radar data over 80 percent of the Earth's land surface, for most of the area between 60?N and 56?S latitude. NASA and the National Geospatial-Intelligence Agency (NGA), formerly known as the National Imagery and Mapping Agency (NIMA), co-sponsored the mission...

While this technology has proven its use as a mapping tool - effective for generating bare earth DEMs at high resolutions (1-3 m) and with high vertical accuracies (15-18 cm) - obstacles remain for its application as a remote sensing tool: * The high cost of collecting LIDAR * The steep learning curve on research and application of using the entire point cloud * The challenges of...

Intensified soil erosion contributes to the degradation of ecosystems. Better estimation of soil erosion across landscapes is a necessary part of understanding ecosystem biogeochemical cycles and ecosystem sustainability. In this study, we used the Unit Stream Power-based Erosion Deposition (USPED) model to estimate the lateral movement of soils across Fort Benning, a military training

No abstract available.

The parameters of ecosystem models are conventionally optimized through nonsequential inversion methods, which treat observations as a whole and lack the flexibility to investigate possible temporal evolution of the model parameters. This research developed a smoothed ensemble Kalman filter (SEnKF) to assess to what extent the parameters and state variables of an ecosystem model can be

Evaluating a range of scenarios that accurately reflect precipitation variability is critical for water resource applications. Inputs to these applications can be provided using location- and interval-specific probability distributions. These distributions make it possible to estimate the likelihood of rainfall being within a specified range. In this paper, we demonstrate the feasibility...

This report compiles selected results from 13 U.S. Geological Survey (USGS) mineral resource assessment studies conducted in Idaho and Montana into consistent spatial databases that can be used in a geographic information system. The 183 spatial databases represent areas of mineral potential delineated in these studies and include attributes on mineral deposit type, level of mineral...