August 31, 2011
In 2009, the Ecuador Ministry of Agriculture, Livestock, Aqua-culture and Fisheries began a ground-breaking land management initiative called SIGTIERRAS. Also known as the National Information System and Management of Rural Lands, SIGTIERRAS is a land-titling program aimed at mapping land parcels and collecting property ownership information for the entire nation.
For farmers and land owners, obtaining an accurate deed to land is a critical step in securing loans. Government-sponsored assistance programs and international organizations also require official land ownership records to receive funding. Johnny Hidalgo Mantilla, executive director of SIGTIERRAS, believes an integrated and transparent national GIS-based information system is fundamental to supporting development and business growth in the country. “An integrated approach to data collection is absolutely necessary to produce consistent parcel boundary definitions and descriptions,” Hidalgo says. “This project is a substantial undertaking because it requires a synchronized effort from property owners, technical crews, officials within neighboring municipalities, as well as SIGTIERRAS representatives.”
The first step in the project was defining the objectives of the multi-year project. These include:
• Analysis and design of an information system for property tax administration;
• Implementation and system maintenance of land information for each municipality at the territorial level;
• The successful training of representatives of each municipality as well as their ability to systematically collect and update land, location, and attribute records;
• Creation and implementation of a repeatable approach for updating farm and land information;
• Final digital mapping (scale 1:5,000) of each municipality, including the use of a unique farm code for each parcel of land;
• The accurate valuation of land and property tax data for each municipality; and
• Generation of final cadastral codes and the publishing of results in the SIGTERRAS system.
With the program objectives clearly outlined, SIGTIERRAS implemented a pilot program in June 2011 focusing first on eight Ecuadorian counties.
For the initial phase of this effort, SIGTIERRAS relied on an existing set of aerial photogrammetric images produced by the country’s Military Geographic Institute (IGM). These images are at a scale of 1:3,000 or greater, depending on each municipality and the density and size of the parcels. Hidalgo and other officials agreed that for the country’s rural land parcels, the most appropriate scale for the cadastral survey orthophotos is 1:5,000. The team decided to use this scale because it’s sufficient to plot maps containing rural parcels that vary from one-half hectare (ha), up to hundreds of hectares. The SIGTIERRAS team also used Trimble NetR9 receivers to capture aerial photos of the area.
To collect the necessary property data, crew members traveled to each farm and walk property boundaries with assistance from the landowner and neighbors. Ensuring ground-level accuracy was a high priority. The crews used the Trimble line of mapping-grade GNSS units designed for mobile GIS data collection including Trimble GeoExplorer series GeoXT handhelds for. Trimble GPS Pathfinder Pro XR receivers and Juno ST and SB series handhelds were also employed for this project.
Working in teams of two, they collected submeter GNSS points at the parcel corners. For the initial pilot project, crew members also entered a basic property description, including crops planted and information about the land’s natural vegetation into the GNSS receiver. According to Hidalgo, measuring and managing location data with the Trimble receivers helped accelerate the on-the-ground survey process by reducing the amount of time required at each property. Using the handhelds allowed the teams to work more quickly because they could access the necessary maps and large data sets directly in the field and on the go.
After completing the survey of each identified piece of property, field workers then assigned a previously defined rural cadastral code. Back at the office, teams used GPS Pathfinder Office software to apply differential correction techniques that enhanced the quality of location data gathered using the GPS receivers. Postprocessing tools used include Trimble DeltaPhase technology. The office team then linked the property descriptions to the location data for each parcel.
During the initial phases of the project, SIGTIERRAS field crews were able to collect pertinent parcel data quickly, spending about an hour at each property. Currently SIGTIERRAS has successfully completed the pilot project, collecting accurate parcel data and georeferenced land information for eight intercontinental counties. Nearly seven percent, or 200,000 parcels of land out of Ecuador’s estimated three million parcels, have been captured and stored in the national GIS system.
The teams averaged the successful survey of approximately seven parcels of land per day, even facing challenging environmental conditions. “In the field, our crew members frequently face dense vegetation and heavy cloud cover,” Hidalgo says. “We were pleased that spec requirements in our pilot project were met--20 centimeters accuracy--even with Ecuador’s diverse landscape.”
Once parcel coordinates and land data are collected, a unique cadaster code is assigned to each section of land. At that point officials perform a series of checks and balances to determine the accuracy of the parcel delineation as well as to investigate the legal land tenure. Once the accuracy is certified by the appropriate municipality, any related land disputes are resolved, and the landowner receives a certificate confirming ownership.
Hidalgo and other SIGTIERRAS officials are extremely pleased with the high level of accuracy of the properties and the speed at which field crews can acquire submeter data about each parcel. “Although we are still in the early stages of this national initiative, we can already see the benefits of using Trimble for data collection,” Hidalgo says. “We’ve established an efficient and repeatable process for accurate mapping that will save us hundreds of man-hours in the field and reduce project costs by at least 25 percent.”
Over the next several years, the GIS database will continue to be established as the repository for Ecuador’s national cadastral information. As additional land data is collected and published, the database will act as a clearinghouse for georeferenced registration records based on physical and legal status of properties. The large-scale SIGTIERRAS initiative will eventually be used to support the country’s more sophisticated survey, taxation, and valuation efforts.
Each of Ecuador’s 220 municipalities will be responsible for updating parcel land records in the property database in the future. Municipalities will work closely with the Public Property Registry, or public appraiser, to maintain survey data. For example, if a parcel of land has to updated, split, is sold, or merged, crews will visit the property, perform field verification, pulling up maps and existing records on Trimble GeoXT handhelds, collect updated measurements and then share the land data with the Property Registry.
Hidalgo is confident his team is taking important steps to establish a national land administration system that will ensure private property ownership and provide critical information for planning and land development throughout the country.
“Without the GNSS technology,” he says, “it would not have been possible to carry out such projects. The GNSS data is a complement to the orthophoto for the rapid parcel measurement.”