The 12th International Lidar Mapping Forum drew a record attendance of more than 750 attendees to their annual gathering last week in Denver. The event took place from Jan.23-25 at the downtown Hyatt Regency. The busy program schedule was well balanced by booths representing 60 companies. The program placed both an emphasis on research and innovation as well as application, with a mix of process oriented sessions, the strategies and hurdles of collection, and innovative LIDAR applications.
The 12th International Lidar Mapping Forum drew a record attendance of more than 750 attendees to their annual gathering last week in Denver. The event took place from Jan.23-25 at the downtown Hyatt Regency. The busy program schedule was well balanced by booths representing 60 companies. The program placed both an emphasis on research and innovation as well as application, with a mix of process oriented sessions, the strategies and hurdles of collection, and innovative LIDAR applications.
This event has become the meeting place for business between the lidar hardware developers and software companies, serving as a one-stop location to meet partners and exchange updates and areas of interest. While the event has strong roots in aerial lidar collection, it has expanded with a complement of mobile lidar vehicles on display this year.
The attendees at ILMF 2012 had their choice of a variety of sessions that were delivered by a good mix of industry, academia, policy creators and practitioners. The primary track centered on data acquisition, data fusion, technical developments, processing, and projects. The ability to process large volumes of lidar point clouds have come a long way since we last attended this event two years ago, however the hardware still far exceeds the capability of software. With each detailed use case presentation the focus of the question and answer period largely revolved around process issues as users quizzed each other to learn methodology and best practices.
Plenary Highlights National Elevation Issues
To lead off the event, we heard about the rigorous work that has gone into the National Enhanced Elevation Assessment. Presenters were Greg Snyder, lidar development at USGS; David Maune, senior product manager, Dewberry (author of the DEM User Manual published by ASPRS) and Larry Sugarbaker senior advisor, USGS National Geospatial Program. There is a growing need for a renewed national elevation dataset that uses lidar technology due to the fact that the National Elevation Dataset is 30-50 years old, and today’s uses require contours, digital surface models, and complete coverage.
The assessment included the analysis of a long list of business uses with five levels of topographic detail and varying frequencies. They then evaluated every one of the business issues along with 25 quality levels with corresponding accuracy and frequency. The outreach to the users included a survey with 721 responses, an interview process with 34 federal workshops, 50 state workshops, and 13 non-gov meetings. The sum total of the assessment amounted to an 870-word report.
The benefit and cost analysis was then compiled from all inputs to put a dollar figure on various cost/benefit scenarios. The synergy of working across federal, state and user needs proved that not only is the cost less, but the benefits are far greater to everyone by working together.
The presenters displayed a range of different scenarios, their cost, the collection frequency, and the percentage with which they met the stakeholder requirements. Scenario 4, with a mixed level of detail over a 15-year collection, has the highest combined net benefit at a cost of $160M per year with conservative benefits estimated at $780M. If there was a need to address 90 percent of all the scenarios, with high quality and frequent collection, the cost would be upwards of $350M, but also with expanded benefits up to $1.5B. To achieve all levels of requirements however would lead to much more cost than benefits.
The use cases from the federal side include :
- population distribution and characteristics
- national biological carbon assessment
- mining regulation and reclamation
- nuclear power plant hazard assessment
- wetlands mapping and characterization
The top 10 business uses (in order of priority, with the top being the most important) are:
- flood risk management
- infrastructure and construction management
- natural resource conservation
- agriculture and precision farming
- water supply and quality
- wildfire management, planning and response
- geologic resource assessment, hazard and mitigation
- forest resource management
- river and stream resource management
- land navigation and safety
The USGS currently spends $2M per year for lidar, but that doesn’t come close to meeting a national-level program. Given current budgetary restrictions, a measured approach is underway to further cost justify such an escalation in lidar expense. The next steps include a formalization of the program and the budget recommendations with outreach to partner agencies and professionals in a number of industries.
Modeling Wildlife Habitat with Lidar
Wesley Newton from the U.S. Geological Survey discussed the use of lidar for wildlife habitat modeling. The USGS works to assess the quality of habitat, population demographics, species survival, and why wildlife are found in specific habitats. The group works to model and explain the mix of wildlife in specific habitat types for management actions. Different species require different vertical structure in grasslands and within forests. The presentation discussed different bird species with different forest structure types. Bird species diversity is often dependent on the amount of foliage, with more birds in areas that are denser.
A management dilemma that the USGS faces is the competing needs of different species. With different, the challenge is to simultaneously manage habitat across species. The USGS relies heavily on statistical models, with the use of study plots that are quantified for vegetation types and structure, that can then be extrapolated to larger forests. Other landscape metrics and land cover methods with imagery and other sources to understand the variation.
The measurement of wildlife include the presence of species, the count the survival rate, and the biomass. The general species model include stand level metrics, landscape metrics with imagery, features with GIS layers, and then the fieldwork. The goal is to develop a number of plausible models, that are continually updated, and then compared.
Lidar has been helping a great deal at the forest level, with data that can’t be quantified in other ways. The lidar point cloud is subtracted from the digital elevation model for a canopy height model, with removal of buildings and other vertical structures. The details on variability are then put into different height bins for canopy, with vertical profiles for different forests. There are fifty different explanatory variables for forests that are then used to predict the species abundance. Models are applied to the landscape, with adaptive models that monitor and model water flows and other variables, to understand the impact of change.
The USGS has flown lidar in Maine for woodcock habitat. In Nebraska the USGS is using lidar to quantify the habitat along the South Platte River, which is ideal habitat for Sandhill Cranes. Not only is the lidar used for habitat assessment, but it’s also being considered as a means to count the cranes. In Wyoming the USGS is using lidar for sagebrush habitat, where different species require different heights of brush. In Nevada, the USGS are mapping streams for spawning habitat of cutthroat trout, understanding good shading areas. The changes within all of these habitats are being closely monitored to understand ongoing impacts.
Overall the event provided a good overview of the exploding use of LIDAR collection, processing, visualization and analysis. Lidar is rapidly gaining favor over traditional photogrammetry and other applications, but there are still plenty of technological hurdles that need to be overcome in order to spur wider adoption.