Selected Geospatial Data Projects and Site News
The following are highlights from some of the geospatial activities currently happening at LTER sites around the network.
Andrews Experimental Forest (Theresa Valentine):
Recent data acquisition: The Upper Blue River drainage adjacent to the Andrews was flown with LiDAR in Fall 2011. This provides the site with extended 1 meter resolution digital elevation models (DEM) for the bare earth (see figure 1) and highest hits returns, and the raw point cloud data. The bare earth DEM has been used to generate new road and stream GIS layers, as well as help provide more accurate boundaries for gauged watershed studies.
Figure 1.Upper Blue River Lidar
Digital Forest: Spatial Models of Vegetation Structure and Composition: The objective of this project is to spatially model current forest structure and composition of the Andrews. These models and data will then be used by other projects in LTER6 (e.g. water and carbon, modeling) to address questions related to the goals of the LTER. In addition, the spatial models of forest structure and composition will be used to understand how forest structure varies in relation to topography. The initial stage of this project will be to create and evaluate spatially models of canopy height and cover, which can be estimated directly from LiDAR. The second phase will be to model other forest structural features, such as biomass and basal area, which require that data from ground plots be used in conjunction with LiDAR. For more information: http://andrewsforest.oregonstate.edu/lter/research/lter6/current.cfm?pid...
Climate Data: Work is underway to develop improved spatial climate data sets (grids) to be used as input for modeling and analysis activities. These include new 1971-2000 mean monthly and annual precipitation grids at 50-m resolution prepared by C. Daly using PRISM (Fig. D-2). The mapping activity served as impetus for the digitizing, cleaning, and organizing of historical datasets collected over the past 60 years at HJ Andrews. Temperature measurements at 50 to 200 new sites within the HJA are being used to develop improved maps of temperature and explore relationships of temperature with topography and cold air drainage. http://andrewsforest.oregonstate.edu/lter/research/lter6/cl/summary.cfm?...
Useful modeling links:
iland: individual-based forest landscape and disturbance model: http://iland.boku.ac.at/tiki-index.php
RHESSys: a GIS-based, hydro-ecological modeling framework designed to simulate carbon, water, and nutrient fluxes. http://fiesta.bren.ucsb.edu/~rhessys/
Baltimore Ecosystem Study (Mark Kather):
Western School of Technology and Environmental Science Baltimore County Public Schools Land Stewardship Project:
On February 2, 2012, sophomores and juniors in the environmental technology magnet program at the Western School of Technology and Environmental Science (WSTES), teamed up to create a land stewardship plan for public school sites in Baltimore County. Teams selected individual schools based on the criterion that it is involved in pursuing Maryland “Green School” status. Students focused in on 5 elementary and 5 middle school sites.
A letter of introduction was prepared by each team and emailed to the green school contact person at the corresponding school. Base maps showing existing topography, roads and parking lots, buildings, streams, and vegetation were prepared and students visited their school and conducted a site analysis. Students then collaborated, they brain stormed, and they researched environmental best management practices that may be appropriate for school sites. They targeted the following strategies: no-mow areas, wooded area reforestation, rain gardens, environmental theme areas, erosion remediation, landscape enhancement, nature trails, and building shade buffers. Reflecting their school’s site analysis, teams began to evolve their land stewardship plans. Unfortunately, due to the short time duration of this project, input from school representatives was not taken into account. However, in April teams will forward their land stewardship plans to their school and follow up opportunities can then be pursued. The schools will also be able to utilize the students’ work with other materials necessary for the “Green School” application process.
These maps were compiled using ArcGIS 9.3 software. The GIS data was supplied by the Baltimore County Office of Information Technology in connection with the BCPS project on improving GIS education. Data layers used to construct the maps include topography, hydrology, roads, buildings, vegetation, tax parcel, and aerial imagery. Students also used Google Earth as an additional aid to study their sites.
Jornada Basin (Ken Ramsey):
The Jornada has several GIS projects currently under development to support site and network integration efforts, including the LTER NIS and EcoTrends project. All long-term research datasets are being processed to relate research data tables to linked GIS features (research sites) within the enterprise geodatabase. This process includes adding identifier, key, and x,y coordinate columns to the comma-separated value data files delivered by the Jornada data catalog, geoportal, and the LTER Data Portal.
The Malpai project and Jornada geoportals are being populated and integrated with Drupal-based data catalogs. The Jornada interactive map is being updated and is based on the enterprise geodatabase. Research maps within the enterprise geodatabase (e.g., vegetation, soils, and geomorphology) are being processed to create EML following GeoNIS best practices.
Konza Prairie (Adam Skibbe):
Data management: At Konza we are currently working to update our GIS catalog. Using high resolution GPS units we have been re-collecting existing locations for ongoing LTER research projects with much greater accuracy. In addition to data found on our website, we will be able to offer a much more robust variety of research project locations once this is completed.
In addition we have been working with updating our aerial photography data holdings. To do this we have had several years of historic aerial photographs, dating back to the 1930s, scanned and are currently creating mosaics and rectifying these images.
GIS Research: There are a number research projects at Konza that are either focused on or heavily use GIS technology. One of these, though not specifically LTER funded, is a project which tracks the movement of our bison herd by using GPS collars. The tracked locations, along with knowledge of burn history, NDVI data, etc. are helping us to better understand how bison use the landscape.
North Temperate Lakes (Aaron Stephenson):
Sevilleta (Mike Friggins):
Currently at SEV we are developing GIS capabilities in terms of providing modern SDE geodatabase driven processing and access for site spatial data and metadata. Perhaps more importantly, we are leveraging remote sensing GIS data to answer questions about ecosystem processes.
SevLTER Co-PI Marcy Litvak, Dan Krofcheck (UNM PhD candidate), Andrew Fox (NEON) and Amy Neuenschwander (UT-Austin) will utilize waveform LiDAR data acquired in 2011 to characterize vegetation structure and estimate above ground biomass within the tower fetches of a network of 8 eddy covariance towers in NM and TX. This represents an ecological gradient from black grama desert grassland on up through spruce-fir coniferous woodlands. The analysis, funded by the NASA ROSES Carbon Cycle program, is intended to reduce uncertainties regarding regional carbon dynamics in the Southwestern US by coupling a more accurate estimate of vegetation structure using full-waveform LiDAR to direct measurements of ecosystem-atmosphere carbon exchange from the towers. The LiDAR and tower data will be incorporated into the Community Land Model (CLM), a land surface model (LSM) using a model-data fusion (MDF) framework to improve regional carbon budgets and predict the response of C dynamics in semi-arid ecosystems to changing climate and disturbance.
|Litvak, Krofcheck and colleagues from Idaho State University are also exploring means of measuring large changes in ecosystem structure, remotely, and relating those measurements to the change in function of the ecosystem as measured in-situ using eddy covariance techniques. In this case the analysis is constrained to piñon-juniper woodlands found at a pair of tower sites and the GIS data used is a time series of 42 images for both sites using the RapidEye constellation of satellites and classified using NDVI (Normalized Difference Vegetation Index) as a proxy for LAI and NDRE (Normalized Difference Red Edge) as an approximate for Chlorophyll concentrations calculations. At one of the PJ sites, all adult piñon in the tower fetch were girdled to simulate piñon mortality. The massive change in ecosystem structure following the selective mortality of the piñon overstory in the manipulation site has resulted in some drastic changes in ecosystem function which researchers hope can be detected using vegetation indices from the time series GIS dataset.|
Virginia Coastal Reserve (John Porter):
The Virginia Coast Reserve uses GIS coupled with remote sensing to track changes in a "high-speed landscape." This includes time-series of GIS layers, some taken from historical maps, others from recent aerial photos or satellite images. On Hog Island (a primary study site) GIS was used to delineate the boundaries between land deposited during different time intervals to create a chronosequence that is used extensively in vegetation and soil studies. In another recent study, GIS was used to examine the rates of marsh-edge erosion in relation to the surrounding landscape. In 2010 the site had flown its first comprehensive LiDAR survey (previous surveys had been restricted to beach areas). Previous comprehensive elevation data lacked sufficient vertical resolution to be usefully applied on a landscape where vertical changes of 10 cm can represent the difference between grassland and shrubland.