Now showing items 21-30 of 125
Current status of Landsat program, science, and applications
(Elsevier Inc., 2019-03-11)
Formal planning and development of what became the first Landsat satellite commenced over 50 years ago in 1967. Now, having collected earth observation data for well over four decades since the 1972 launch of Landsat-1, ...
Differing Levels of Forestry Best Management Practices at Stream Crossing Structures Affect Sediment Delivery and Installation Costs
Forestry best management practices (BMPs) are used to reduce sedimentation from forest streamcrossings. Three BMP treatments (BMP , BMP-std, and BMP+) were applied to three forest road stream crossings (bridge, culvert, ...
Estimating biophysical parameters of individual trees in an urban environment using small footprint discrete-return imaging lidar
Quantification of biophysical parameters of urban trees is important for urban planning, and for assessing carbon sequestration and ecosystem services. Airborne lidar has been used extensively in recent years to estimate ...
Reducing Reforestation Costs in Lebanon: Adaptive Field Trials
Lebanon’s Ministry of Environment initiated a project in 2009 to determine low-cost reforestation techniques for stone pine (<i>Pinus pinea</i>) and Lebanon cedar (<i>Cedrus libani</i>) for large-scale land rehabilitation ...
Implementation of Forestry Best Management Practices on Biomass and Conventional Harvesting Operations in Virginia
Logging residues are often utilized as a Best Management Practice (BMP) for stabilizing bare soil on forest harvesting operations. As utilization of woody biomass increases, concern has developed regarding availability of ...
Caveating Behavior Modification Approaches to Conservation
Scaling participation in payments for ecosystem services programs
Payments for ecosystem services programs have become common tools but most have failed to achieve wide-ranging conservation outcomes. The capacity for scale and impact increases when PES programs are designed through the ...
A life course approach to understanding social drivers of rangeland conversion
(Ecology and Society, 2017-01)
Grassland to woodland conversion, also known as woody plant encroachment (WPE), is a global-scale phenomena caused in large part by changes in social processes that affect rural land use patterns. Woody plant encroachment ...
Combined Use of Airborne Lidar and DBInSAR Data to Estimate LAI in Temperate Mixed Forests
The objective of this study was to determine whether leaf area index (LAI) in temperate mixed forests is best estimated using multiple-return airborne laser scanning (lidar) data or dual-band, single-pass interferometric synthetic aperture radar data (from GeoSAR) alone, or both in combination. In situ measurements of LAI were made using the LiCor LAI-2000 Plant Canopy Analyzer on 61 plots (21 hardwood, 36 pine, 4 mixed pine hardwood; stand age ranging from 12-164 years; mean height ranging from 0.4 to 41.2 m) in the Appomattox-Buckingham State Forest, Virginia, USA. Lidar distributional metrics were calculated for all returns and for ten one meter deep crown density slices (a new metric), five above and five below the mode of the vegetation returns for each plot. GeoSAR metrics were calculated from the X-band backscatter coefficients (four looks) as well as both X- and P-band interferometric heights and magnitudes for each plot. Lidar metrics alone explained 69% of the variability in LAI, while GeoSAR metrics alone explained 52%. However, combining the lidar and GeoSAR metrics increased the R<sup>2</sup> to 0.77 with a CV-RMSE of 0.42. This study indicates the clear potential for X-band backscatter and interferometric height (both now available from spaceborne sensors), when combined with small-footprint lidar data, to improve LAI estimation in temperate mixed forests....
Prediction of Canopy Heights over a Large Region Using Heterogeneous Lidar Datasets: Efficacy and Challenges
Generating accurate and unbiased wall-to-wall canopy height maps from airborne lidar data for large regions is useful to forest scientists and natural resource managers. However, mapping large areas often involves using ...