Digital Commons Network^™

A Dynamic Landsat Derived Normalized Difference Vegetation Index (Ndvi) Product For The Conterminous United States, Nathaniel P. Robinson, Brady W. Allred, Matthew O. Jones, Alvaro Moreno, John S. Kimball, David E. Naugle, Tyler A. Erickson, Andrew D. Richardson

Numerical Terradynamic Simulation Group Publications

Satellite derived vegetation indices (VIs) are broadly used in ecological research, ecosystem modeling, and land surface monitoring. The Normalized Difference Vegetation Index (NDVI), perhaps the most utilized VI, has countless applications across ecology, forestry, agriculture, wildlife, biodiversity, and other disciplines. Calculating satellite derived NDVI is not always straight-forward, however, as satellite remote sensing datasets are inherently noisy due to cloud and atmospheric contamination, data processing failures, and instrument malfunction. Readily available NDVI products that account for these complexities are generally at coarse resolution; high resolution NDVI datasets are not conveniently accessible and developing them often presents numerous technical and methodological …

A Dynamic Landsat Derived Normalized Difference Vegetation Index (Ndvi) Product For The Conterminous United States, Nathaniel P. Robinson, Brady W. Allred, Matthew O. Jones, Alvaro Moreno, John S. Kimball, David E. Naugle, Tyler A. Erickson, Andrew D. Richardson

Numerical Terradynamic Simulation Group Publications

Satellite derived vegetation indices (VIs) are broadly used in ecological research, ecosystem modeling, and land surface monitoring. The Normalized Difference Vegetation Index (NDVI), perhaps the most utilized VI, has countless applications across ecology, forestry, agriculture, wildlife, biodiversity, and other disciplines. Calculating satellite derived NDVI is not always straight-forward, however, as satellite remote sensing datasets are inherently noisy due to cloud and atmospheric contamination, data processing failures, and instrument malfunction. Readily available NDVI products that account for these complexities are generally at coarse resolution; high resolution NDVI datasets are not conveniently accessible and developing them often presents numerous technical and methodological …

The Influence Of Tree Height On Lidar’S Ability To Accurately Characterize Forest Structure And Spatial Pattern Across Reference Landscapes, Haley L. Wiggins

Graduate Student Theses, Dissertations, & Professional Papers

Successful restoration of degraded forest landscapes requires reference models that adequately capture structural heterogeneity at multiple spatial scales. Field-based methods for assessing variation in forest structure are costly and inherently suffer from limited replication and spatial coverage. LiDAR is a more cost-effective approach for generating landscape-scale data, but it has a limited ability to detect understory trees. Increased understanding of appropriate height cut-offs for trees to be reliably included in LiDAR-based analysis could improve applications of LiDAR to assessments of landscape-scale forest structure. Toward that end, I investigated the effect of varying tree-height criterion (minimum height cutoffs of 6, 9, …

A Biogeographic Perspective On The Impacts And Importance Of Rodent Granivory On Native Vs. Invasive Plants, Jacob Elias Lucero

Graduate Student Theses, Dissertations, & Professional Papers

One of the most well-known explanations for the success of invasive plants in novel environments is enemy release, which predicts that 1) invasive plants are limited by natural enemies in the native range but not the non-native range, and 2) native competitors in recipient communities remain limited by their natural enemies. Despite considerable empirical attention, very few studies have tested these basic predictions, especially with respect to generalist herbivores. We tested whether invasive cheatgrass (Bromus tectorum) has experienced enemy release from granivorous rodents – an important guild of generalists – using exclosures and experimental seed additions in western Asia (where …

Enhancing Conservation With High Resolution Productivity Datasets For The Conterminous United States, Nathaniel Paul Robinson

Graduate Student Theses, Dissertations, & Professional Papers

Human driven alteration of the earth’s terrestrial surface is accelerating through land use changes, intensification of human activity, climate change, and other anthropogenic pressures. These changes occur at broad spatio-temporal scales, challenging our ability to effectively monitor and assess the impacts and subsequent conservation strategies. While satellite remote sensing (SRS) products enable monitoring of the earth’s terrestrial surface continuously across space and time, the practical applications for conservation and management of these products are limited. Often the processes driving ecological change occur at fine spatial resolutions and are undetectable given the resolution of available datasets. Additionally, the links between SRS …

Using Thermal Infrared Imagery To Estimate Soil Hydraulic Parameters: A Novel Approach, Matthew B. Thomas

Undergraduate Theses, Professional Papers, and Capstone Artifacts

In this study, skin temperature measured with a thermal infrared (TIR) camera was used to estimate soil hydraulic parameters. These physical properties that control how soils transport and retain water are notoriously difficult to measure in the field due to spatial variability. Laboratory experiments were set up to record surface skin temperature response in a clean soil column using a TIR camera after an artificial wetting event. An array of thermocouples, a net radiometer, heat flux sensor and weather station were used to constrain the TIR data and the energy budget during the experiment. The soil column surface was then …

Utilization Of Landsat Imagery To Assess The Impacts Of Oil And Gas Extraction On The Tazovsky Peninsula, Siberia, Nicholas B. Kline

Graduate Student Theses, Dissertations, & Professional Papers

Climatic warming of the Arctic is leading to landscape change through cascading biophysical feedbacks; development, such as oil and gas exploration and extraction, can accelerate or worsen these impacts. Due to restricted access to oil and natural gas fields, in situ environmental impact studies are only allowed in some regions. Satellite imagery analysis provides a mean for assessing impacts in areas with limited access. The Yamburg oil and gas field in western Siberia serves as a case study to assess the effects of infrastructure on an Arctic landscape.

This project quantifies the land-cover disturbance that occurred during the development and …