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Geomatics and Surveying in Support of Land Administration

Implementing Tenure Security for All

Today’s geospatial technology means that land administration systems can increasingly be implemented for the benefit of all. It is now possible to conceive approaches to capturing the unrecorded geometry of boundaries for the billions of unrecognised land interests or spatial units. In addition, new approaches are becoming apparent for the maintenance of collected data. Examples from the field show that we’re well on the way to responding to the challenge. From a geomatics and geoscience perspective, many tools are already available to support development, but further steps are needed to operationalise them at scale. Read on for an article investigating a few of the emerging options.

(By Christiaan Lemmen, Rohan Bennett and Paul Saers, The Netherlands)

Land information tells us about the ownership, use, value and development of land – whether statutory, informal or customary. It provides an overview of people-to-land relationships. It shows us how people relate to the space around them. The information can be used to realise responses to major societal challenges, e.g. the UN 2030 Agenda for Sustainable Development. Geoinformation and Earth observation provide the inputs. These include satellite and drone imaging and mapping, global navigation satellite system (GNSS) positioning, cartography, spatial data infrastructures and many surveying sub-disciplines. This article takes a look at how each of these tools is helping to operationalise land administration at scale – and also what challenges need to be overcome to realise the potential.  

Using Imagery

In the last few years, there has been considerable buzz surrounding ‘fit-for-purpose land administration’. The approach argues for cost-effective, time-efficient, transparent, scalable and participatory systems. The philosophy is driven by the idea that, in many situations, it is sufficient to identify visual boundaries based on imagery. This means making use of photographs, images or topographic maps in the boundary adjudication and mapping activities. Alternatively, apps on mobile devices can be combined with imagery to identify plots, thus avoiding misinterpretation of visual boundaries on the image. Images can be collected from satellites, traditional aircraft or unmanned aerial vehicles (UAVs). In cases of high land values or intensive land use, the field surveys can be conventional land surveys using high-precision total stations or GNSS.

Standardising Models

Alongside the push for the increased use of imagery, global standards such as the Land Administration Domain Model (LADM) focus on standardised modelling of information at the conceptual level. The model does not include processes for initial data acquisition, data maintenance and data publication. This is because those processes were considered to be country-specific when the first edition of LADM was prepared; a generic and global approach was likely to be difficult to model. This view now needs reconsideration, however. The fit-for-purpose land administration approach arguably allows for identification of more generic process-related modules in data acquisition and data handling. Standardisation can also make it easier to monitor the progress of global indicators relating to land tenure security.

Focusing on Processes

So what are some of these processes that might be supported? Examples include initial data acquisition, georeferencing (based on elevation models), identification of boundaries, surveying (based on imagery, conventional surveys, UAVs, digital pens for imagery and handwriting, feature extraction/data cleaning, radar), area management, linking rights, restrictions and responsibilities (RRRs) to spatial units, linking (groups of) persons to (shares in) RRRs, public inspection, publication of land data, formalisation, map renovation and quality improvement and digital archiving. Computerising large sets of legacy data (maps and archives) requires analogue-to-digital conversion, georeferencing and linking to digital data from other sources. Data may be used for taxation, tenure security purposes, slum upgrading, city management and so on. This also includes land use and zoning plans implemented by land consolidation and land readjustment processes. Statistical information such as fragmentation index and price index may need to be derived from the land administration. Imagery may be available on paper or on mobile devices in the field, or both.

Creating a Tenure Atlas

Another challenge in many countries is that several authorities may play a role in the process of recognising, recording, registering and managing the land tenure, and they may each maintain their own land information sets. Therefore, at national level, coordination is needed; a Land Tenure Atlas could be developed to provide an overview of the spatial distribution of legitimate tenure types throughout a country – be they customary, informal, private, public or otherwise. The Atlas may further include a layer for national and administrative boundaries and potentially a layer for planned and ongoing projects in land administration. The Atlas should be able to be aggregated to global level, enabling linkage to proposals for international data exchange representing the different RRRs in use within countries.

Utilising Devices

Surveyors and geoprofessionals focus on geometric accuracy, and this focus should result in quality labels identifying the relative and absolute accuracy of geometric data. This is relevant for later adjustment and integration of data from different sources collected with different instruments and tools in different approaches. But land administration is not only about geometric data. Talking about quality in land administration means not only talking about geometric accuracy, but also about ‘linking’ between polygons (spatial units) and people (right-holders). It would be nice if functionalities could be combined in one single device, i.e. linking functionalities for image-based data acquisition to handheld GPS, biometric data (fingerprint identification and facial recognition) and voice/video recording in support of object identification. Such devices would also be useful for inspections, for fieldwork related to building and construction permits, for cadastral maintenance, etc. Land data collected on many devices could deliver results in formats based on operational standards.

Integrating with OGC

The Open Geospatial Consortium (OGC) recognises that worldwide, effective and efficient land administration is an ongoing concern, inhibiting economic growth and property tenure. Existing approaches are at significant risk of data loss and failure due to disasters and lack of interoperability. The charter members of an established OGC Land Administration Domain Working Group are seeking to identify enabling standards and best practices to guide countries in a programmatic way towards establishing more cost-effective, efficient and interoperable land administration capabilities. Attention will be paid to upgrading currently manual processes to semi-automated ones, and to suggesting new approaches for data acquisition that are more automated and flexible. These challenges are faced today in ‘developing’ and ‘developed’ countries alike.

Developing Cooperation

Enabling standards are also being developed with other domain working groups within OGC, such as LandInfra. Partnerships and liaisons with other associations and standards developing organisations (SDOs) will be developed to address interoperability issues that span the land administration community of practice, geographic information systems and the broader IT environment. Examples include linkages with ISO TC 211 regarding the LADM as well as those SDOs responsible for IT standards related to topics such as security, the internet and mobile services. Further, the DWG will be open to participation by any interested organisations and individuals.

Industrialising Approaches

The geospatial industry provides tools, products and services in support of a number of important processes required in fit-for-purpose land administration. Image-based acquisition of cadastral boundaries needs access to huge image libraries – including historic imagery – to support large-scale implementations. Detection and selection of cloud-free imagery is needed to create cloud-free compositions, possibly from different sensors. By using orthophotos to produce spatial frameworks, the imagery is typically linked to the national geodetic reference frame through GNSS in space/on the aircraft and on the ground. Furthermore, automated feature extraction and feature classification appear to be very promising developments for the generation of coordinates of visual objects from imagery, and Lidar and radar technologies can also be used for this purpose. ‘Pre-defined’ boundaries resulting from feature extraction may be plotted on paper or visualised in interfaces, and can then be declared identical to cadastral boundaries in the field.

Modernising Demarcation

In general, fixing boundaries should be avoided in the preliminary stages. It has been shown that demarcation with monuments or beacons often takes 80 to 90% of the surveyor’s time. If demarcation is an absolute requirement, let people place the beacons themselves. Otherwise, it is a good idea to explore modern demarcation methods – smart markers could provide a good alternative. Modern markers like the traceable 3D radio frequency identification (RFID) markers can be detected and identified from a distance of several metres using a simple smartphone. The RFID in the marker can store administrative and positional data. It eliminates all known drawbacks of traditional markers. They could be used as main markers or georeferenced markers, supplemented by locally surveyed points demarcated with low-cost materials. RFID boundary marker strips cost less than EUR1 to produce – although that does not necessarily make it affordable in some countries, of course.   

Utilising UAVs

UAV or ‘drone’ technology is rapidly developing, although autogyro platforms may represent another possible solution for aerial image capturing. Such platforms can operate at low to medium heights, thus largely eliminating the risk of images being obscured by cloud. In some cases, walking can be an alternative to low-altitude flying, e.g. using a portable 3D laser scanning device, the surveyor can map a strip extending 200 metres to each side of the trajectory on foot.

Handling the logistics

Processes such as initial data acquisition may concern millions of spatial units (parcels) for which people-to-land relationships have to be determined. The organisation of this process requires geospatial support in logistics and case/task management based on geoinformation. This starts with gaining an overview of the density of information. This is about estimating the amount of spatial units in a project area for planning purposes. Provision of materials and tools to data collectors can involve paper-based or digital approaches. A paper-based approach entails using plotted images in the field. This means that the collected field-boundary evidence can be left with the local people, providing a scan is available for the land administration authority. However, even paper-based approaches require a comprehensive range of geospatial technologies. Logistics activities include the processes of creating awareness of and announcing participatory approaches, agreeing on citizens’ roles in the land administration process, and publishing status information online/offline, as well as performing checks on completeness before leaving a location. Collecting copies of people’s ID, photos, signatures, fingerprints and video/voice recording requires field devices and battery power/electricity.

Handling maintenance

Data maintenance can be ‘programme driven’ (systematic) or ‘sporadic’. ‘Programme driven’ means a complete and systematic new acquisition after some time. ‘Sporadic’ means case by case in a ‘transaction-driven’ way and relates to transactions in the land market (buying/selling, mortgaging, etc.). Quality upgrading can be part of the maintenance process. This may be required after digitisation of legacy data or in the case of urbanisation or urban planning. It is crucial that data collected using survey approaches based on different accuracies can be integrated together. This may require adjustment of new observations to existing coordinates in the field or within GIS. Quality upgrading may also entail integration of 3D cadastral data (this includes integration with standards such as IndoorGML, InfraGML, LandXML, CityGML, BIM/IFC) and marine cadastre.

Concluding remarks

Implementation of all the processes presented here is currently undertaken in different places based on customisation from available databases and GIS technology. This is a time-consuming activity which demands GIS and ICT development expertise. Standardisation is required for those processes and needed in order to bring scalable approaches – ones which can be easily implemented based on the defined purposes of each land administration project.

Further reading

  • Enemark, Stig, McLaren, Robin, Lemmen, Christiaan, 2015: Fit-For-Purpose Land Administration – Guiding Principles. UN-HABITAT/GLTN, Nairobi, Kenya
  • GIM International, 2016. Special Issue on Fit-For-Purpose Land Administration for Sustainable Development. Geomares Publishing, Lemmer, The Netherlands
  • OGC, 2016, Domain Working Group (DWG) Charter Land Administration. Open Geospatial Consortium. http://www.opengeospatial.org/projects/groups/landadmin

Biographies of the authors

Christiaan Lemmen

Christiaan Lemmen holds a PhD from Delft University, The Netherlands. He is a geodetic advisor at Kadaster International and visiting researcher at University of Twente/ITC, The Netherlands. He is director of the FIG Bureau OICRF. He is co-editor of ISO 19152 LADM.

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Rohan Bennett

Rohan Bennett gained his doctorate from the University of Melbourne, Australia. He is an associate professor working in land administration at the University of Twente/ITC, The Netherlands, where he is also director of the School for Land Administration Studies at ITC.

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Paul Saers

Paul Saers has an MSc in geodesy and geoinformatics. He is a geodetic advisor at Kadaster International in The Netherlands. He is specialised in the management of computerised land administration systems, BPR, ERP and QMS.

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Viernes 17 de Marzo del 2017

Así será la Misión de Exploración 1 de la nave Orión

En una entrada pasada ofrecí una breve introducción al programa SLS-Orión. Hablé acerca de la nave Orión y de su módulo de servicio, y acerca del cohete que se está desarrollando para su lanzamiento, el SLS. Como también apunté en esa entrada, la primera misión de prueba de un sistema SLS-Orión, llamada EM-1 (Exploration Mision 1), está prevista para finales del 2018. Esta misión no será tripulada; pero, de ser exitosa, la siguiente misión, la EM-2, sí se planea que lo sea.

En este punto es necesario decir que, a petición de la nueva administración, en la actualidad se está llevando a cabo un estudio sobre la posibilidad de dotar de tripulación a la EM-1 con objeto de acelerar el programa espacial tripulado. Se espera que este estudio esté completo para principios de la primavera, por lo que en esta entrada voy a hablar acerca de cómo se plantea la misión EM-1 en la actualidad.

En realidad, el sistema Orión está formado por el módulo de mando, o CM (Command Module o Crew Module), el módulo de servicio, o SM (Service Module), y la torre de escape, o LAS (Launch Abort System), la cual entraría en servicio para separar al módulo de mando del cohete en caso de explosión del lanzador. Dado que el LAS se separa del conjunto una vez se ha producido con éxito el lanzamiento, utilizaré el término Orión para referirme al conjunto formado por la unión entre el CM y el SM, los cuales permanecen unidos hasta pocos momentos antes de que el CM efectúe la reentrada en la atmósfera a su regreso a la Tierra.

Sistema Orión. Fuente: NASA.

La EM-1 tiene por objetivo volar a la Luna e insertarse en una órbita alrededor de nuestro satélite cuyo punto más alejado de su superficie será de unos 70.000 km. A esta órbita la llamamos Órbita Retrógrada Distante, o DRO, del inglés Distant Retrograde Orbit. Es retrógrada porque en ella la nave volará en sentido contrario al de rotación de la Luna, y es distante porque, como se ha dicho, el apolunio de dicha órbita se situará a unos 70.000 km de distancia. Para conseguir insertarse en esta órbita y después regresar a la Tierra, a lo largo de EM-1 se habrán de dar numerosas maniobras propulsivas.

En primer lugar, Orión será lanzado al espacio por el cohete SLS desde el complejo de lanzamiento 39B en el Centro Espacial Kennedy de la NASA en Florida. Después del lanzamiento, Orión estará aún acoplado en órbita alrededor de la Tierra a una etapa propulsora llamada ICPS (Interim Cryogenic Propulsion Stage) cuya función es la de impulsar al conjunto a la Luna gracias a un encendido de su motor en una maniobra que se conoce como Inyección Trans-Lunar, o TLI, del inglés Trans-Lunar Injection

ICPS unido a Orión en órbita alrededor de la Tierra antes del TLI. Fuente: NASA.

Gracias al TLI se consigue el incremento de velocidad necesario para que Orión se aleje de la Tierra siguiendo una trayectoria que lo llevará a encontrarse con la Luna unos días más tarde. De camino al satélite, el ICPS se separa de Orión, dejando que los módulos de mando y servicio unidos hagan el resto del viaje en solitario.

Durante la travesía, los datos de la trayectoria son analizados constantemente en tierra gracias al seguimiento que se hará de la nave a través de la Red de Espacio Profundo, uno de cuyos tres complejos se encuentra en Robledo de Chavela, en la provincia de Madrid. De haber algún tipo de desviación en la trayectoria que resultara en no llegar al entorno lunar en las condiciones idóneas, el módulo de servicio será el encargado de corregir el curso a través de pequeños encendidos ejecutados por su sistema de propulsión. Cada una de estas maniobras de corrección recibe el nombre de OTC, o Outbound Trajectory Correction.  

Esquema de la misión EM-1. Fuente: Airbus.

Al aproximarse a la Luna, la atracción gravitatoria de este cuerpo hará que la trayectoria seguida por Orión se curve alrededor del satélite hasta sobrevolarlo a unos 100 km de altitud. Es aproximadamente en ese punto donde el SM ejecutará un encendido llamado OPF, o Outbound Powered Flyby. El propósito de la maniobra OPF es colocar a Orión en una trayectoria alrededor de la Luna que un tiempo después lo lleve a un punto en el que se darán las condiciones ideales para insertar a Orión en la órbita de destino, la referida DRO. Esta inserción se ejecuta mediante otra maniobra propulsiva que tiene lugar más adelante y que recibe el nombre de DRI, o Distant Retrograde orbit Insertion.

Una vez insertado en la DRO, el conjunto CM/SM estará volando a lo largo de esa órbita durante unos seis días. A pesar de que la DRO es una órbita bastante estable, no se descarta que se pueda necesitar alguna pequeña maniobra de corrección para su mantenimiento. Estas maniobras son referidas como OM, de Orbit Maintenance.

Después de estos seis días, la nave efectuará la primera maniobra con la que se iniciará el regreso a la Tierra: la DRD, o Distant Retrograde orbit Departure. Mediante la DRD, la nave saldrá de la órbita DRO, haciendo que la trayectoria seguida vuelva a aproximarse a las cercanías de la Luna, de nuevo hasta una distancia de unos 100 km sobre su superficie. Será alrededor de este punto en el que la nave ejecutará la maniobra RPF, o Return Powered Flyby, por la que se la impulsará definitivamente de vuelta a la Tierra.

Al igual que en el tramo de viaje hacia la Luna, a lo largo de la travesía a la Tierra también es posible que sea necesaria alguna corrección de la trayectoria para procurar que la nave entre en la atmósfera en el punto deseado y con el ángulo adecuado. En este caso, a cada una de estas maniobras de corrección se las llama RTC, o Return Trajectory Correction.

Una vez llegado el conjunto CM/SM a las inmediaciones de la Tierra, el SM se separará del CM para que éste efectúe la reentrada en la atmósfera. Esta reentrada se hará a una velocidad de unos 11 km/s, que es la que la nave tiene en su retorno de la Luna, y llevará a la nave a amerizar cerca de la costa de San Diego, en el Océano Pacífico.

Como vemos, la EM-1 es una misión ambiciosa en la que se probarán muchos elementos y sistemas por primera vez y en la que se realizarán numerosas maniobras de diferentes características. A lo largo de los próximos meses, hasta su lanzamiento, seguiremos visitando su evolución junto con la de varios de sus sistemas, así como hablaremos sobre temas relacionados con los hitos que se vayan consiguiendo en su puesta a punto. 

Jueves 16 de Marzo del 2017



In January 2016, staff from New Zealand’s Department of Conservation (DOC) were supplied with tablets and smartphones equipped with Survey123 for ArcGIS, a form-centric mobile data collection application. The Hokitika township biodiversity monitoring field team used this mobile app as well as their current paper-based capture methods to evaluate the potential of digital data collection technologies in their workflows. This undertaking showed that not only can Survey123 improve efficiency and reduce field data capture operational costs, but it can also make captured data available easily and instantly for visualisation and analysis.

(By Ismael Chivite, Senior Product Manager, Esri)

Like many other government departments, the New Zealand DOC is going through a digital transformation, replacing paper-based workflows with end-to-end business processes in which information flows instantly across staff teams, departments and – when appropriate – the public. Modern enterprise geographic information system (GIS) technology allows everyone in an organisation to create, access and share information anywhere, anytime and from any device, making their work more efficient and meaningful.

At the New Zealand DOC, wildlife surveys are typically conducted using paper booklets. “The paper-based methodology that we use at the moment is functional, but it requires a massive downstream team to digitise that information. It’s sometimes even necessary to go back to the field team to confirm the data because it’s unreadable due to smudging or rain,” says Benno Kappers, DOC natural heritage information project leader. “Real-time mobile data collection can significantly reduce downstream efforts.”


A pilot programme was initiated to expose the New Zealand DOC staff to using mobile devices for in-field data capture as well as to compare the end-to-end system and organisational processes of both the electronic and traditional paper-based collection methods. Field crews were provided with Android smartphones and tablets. The software on these devices was Esri’s Survey123 for ArcGIS, a data gathering mobile app that speeds up the collection process using simple forms. The programme’s team visited three remote locations on New Zealand’s South Island to survey possum crossings along fixed transects (paths).


Using a simple spreadsheet and the mobile app’s desktop companion tool, Survey123 Connect for ArcGIS, customised forms were created and published in the ArcGIS platform. These forms were then downloaded to the mobile devices to facilitate the collection of information in the field.

Survey123 provided a simple, intuitive interface for users to input field data, which enabled staff to concentrate on making observations rather than on the process of recording them, which was one of the issues with paper-based data collection. Validation rules and expressions configured in the forms reduced the number of user-input errors.


Capturing data via traditional paper-based methods involves not just recording field data but also scanning and uploading it to the server, as well as physical logistics such as inventorying and shipping completed booklets. Much of the work in these processes was greatly simplified – if not eliminated – with app-based data collection.

Collecting data through forms on smartphones provided New Zealand DOC with greater control of field-user input. “People became far more concise about what they needed to say,” explains Kappers. “That is helpful not only from an efficiency perspective but also from a data management one.” Through the use of forms, the data captured was better structured than with paper submissions, and error-prone digitisation processes were eliminated as well.


Getting feedback on paper-recorded data can take several months. After inputting information into Survey123, captured data was directly transferred back to the ArcGIS platform, where other members of the organisation could access the data in tables, maps and other types of information products. This real-time integration of field-collected data into an enterprise GIS platform made the storage, quality assurance, analysis and viewing of information more efficient and less costly.


Not only did the new software make the processes that staff undertook more efficient and less costly, it even rendered some processes unnecessary. Many tasks – including printing field booklets for every recorded plot, scanning the pages and uploading the scans to the server; packing, sending and tracking field booklets to the server in Christchurch; and issuing, digitising and performing quality assurance on booklets – have all been made obsolete due to the capabilities of Survey123 for ArcGIS. Additionally, in the pilot programme, these capabilities showed a reduction of 336 staff hours per monitoring method, per season.


For the New Zealand DOC, digital data collection with smartphones has been proven to make processes more efficient, in particular in downstream procedures but also in preparation work. In addition, departments can now provide almost-instant feedback on the data that staff supply, and once this data is integrated into online maps it can be shared with numerous citizen groups and stakeholders in the community with an interest in wildlife conservation, natural resource protection and stewardship of the planet. “These measurements that we undertake follow strict national protocols and could all be followed by community groups as well,” comments Kappers. “If Survey123 allows us to share these forms with private community groups, the same information management which enables us to start comparing measurements of New Zealand’s public land can also be applied to private land parcels. And that is a really valuable contribution to make.”


New features and fixes are added to Survey123 for ArcGIS through monthly upgrades to the product. High-priority items in the road map include adding the ability for field users to capture areas and linear features as well as location data. Additionally, improvements are being made to workflow editing capabilities, including the ability to update existing database records. These two new features will become available in the first half of 2017 across all supported platforms.

About the author

Ismael Chivite works as a senior product manager at Esri. With over 20 years of GIS experience, Chivite is passionate about building ArcGIS products that help organisations use geography to improve the way they work.

Jueves 09 de Marzo del 2017



Ha sido captada por el telescopio espacial Kepler y es la primera imagen real que vemos del sistema solar de TRAPPIST-1, situado a 40 años luz de nosotros, desde que se anunció el descubrimiento de exoplanetas que alberga.

Los científicos no detectaron estos siete exoplanetas de forma directa, sino a través de los pequeños eclipses que causan cuando pasan delante de la estrella. Es decir, durante su órbita, cuando un planeta pasa delante de su astro, disminuye el brillo de éste, momento que es detectado por los telescopios que apuntan a ese astro. Esta técnica se denomina de tránsito.

Según ha explicado la NASA en un comunicado, la animación que han ofrecido esta semana muestra la cantidad de luz detectada por cada píxel en una pequeña sección de la cámara que lleva el telescopio KeplerLa luz procedente de la estrella TRAPPIST-1 es la que aparece en el centro de la imagen.


Entre el 15 de diciembre de 2016 y el pasado 4 de marzo, Kepler observó la estrella TRAPPIST-1 durante 74 días. Esta animación, en concreto, recoge 60 fotografías tomadas por la cámara el 22 de febrero. Durante una hora, tomó 60 imágenes, una por minuto.

De momento, en el archivo de exoplanetas o mundos fuera del Sistema Solar hay más de 3.450 objetos y su descubrimiento avanza a buen ritmo. Los hay con tamaños y características muy diversas, y el objetivo principal es llegar a encontrar un planeta que pueda ser considerado gemelo de la Tierra.

TRAPPIST-1 es una estrella ultrafría y es mucho más pequeña que nuestro sol. Este tipo de astros son los más comunes, pues representan aproximadamente el 75% de la estrellas que hay en nuestra galaxia.

Los científicos creen que los siete exoplanetas del sistema de TRAPPIST-1 podrían albergar agua líquida y tener temperaturas moderadas debido a la distancia a la que se encuentran de su estrella. Sin embargo, a los astrofísicos les gustaría encontrar un mundo que, además de que pueda tener agua líquida, orbite a un astro como el Sol pues creen que las superficies de los siete exoplanetas de TRAPPIST-1 podrían estar sometidos también a altísima radiación.

Lunes 13 de Marzo del 2017

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