Spatial analysis of the accuracy of the cadastral parcel boundaries

Land fragmentation is a phenomenon which constitutes one of the biggest obstacles to profitable agricultural production. Measurable estimation of this phenomenon is possible by a number of known indicators, based on the surface area of parcels in the given area, their location in space and belonging to individual farms. This method of calculation of the indicators is inaccurate due to the phenomenon of neighbourhood of plots which belong to the same owners. For the purposes of calculating the ratios of actual fragmentation of land, these parcels should be treated as one complex. The article presents a proposal for the adjustment of existing methods of determination of the fragmentation of land indicators, taking into account these phenomena. The object of the research covered area of the voivodeship of Malopolska located in the southern part of Poland. Developed by the authors, method of calculation of land fragmentation indicators, based on complexes of land belonging to the same owners (complexes of plo...

A new approach to calculate the land fragmentation indicators taking into account the adjacent plots

Best Practices 3D Cadastres: Extended version

Accurate and up-to-date information on the spatial and geographical characteristics of agricultural areas is an indispensable value for the various activities related to agriculture and research. Most agricultural studies and policies are carried out at the field level, for which precise boundaries are required. Today, high-resolution remote sensing images provide useful spatial information for plot delineation; however, manual processing is time-consuming and prone to human error. The objective of this paper is to explore the potential of deep learning (DL) approach, in particular a convolutional neural network (CNN) model, for the automatic outlining of agricultural plot boundaries from orthophotos over large areas with a heterogeneous landscape. Since DL approaches require a large amount of labeled data to learn, we have exploited the open data from the Land Parcel Identification System (LPIS) from the Chartered Community of Navarre, Spain. The boundaries of the agricultural plots obtained from our methodology were compared with those obtained using a state-of-the-art methodology known as gPb-UCM (global probability of boundary followed by ultrametric contour map) through an error measurement called the boundary displacement error index (BDE). In BDE terms, the results obtained by our method outperform those obtained from the gPb-UCM method. In this regard, CNN models trained with LPIS data are a useful and powerful tool that would reduce intensive manual labor in outlining agricultural plots.

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Deep Learning for Automatic Outlining Agricultural Parcels: Exploiting the Land Parcel Identification System

Classical topological relation expressions and computations are primarily based on abstract algebra. In this article, the representation and computation of geometry-oriented topological relations (GOTR) are developed. GOTR is the integration of geometry and topology. The geometries are represented by blades, which contain both algebraic expressions and construction structures of the geometries in the conformal geometric algebra space. With the meet, inner, and outer products, two topology operators, the MeetOp and BoundOp operators, are developed to reveal the disjoint/intersection and inside/on-surface/outside relations, respectively. A theoretical framework is then formulated to compute the topological relations between any pair of elementary geometries using the two operators. A multidimensional, unified and geometry-oriented algorithm is developed to compute topological relations between geometries. With this framework, the internal results of the topological relations computation are geometries. The topological relations can be illustrated with clear geometric meanings; at the same time, it can also be modified and updated parametrically. Case studies evaluating the topological relations between 3D objects are performed. The result suggests that our model can express and compute the topological relations between objects in a symbolic and geometry-oriented way. The method can also support topological relation series computation between objects with location or shape changes.

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Geometric Algebra Model for Geometry-oriented Topological Relation Computation

This paper presents a transition method from a 2D cadastre to a 3D+time system, using the available software, based on the official spatial data registers. For over two decades in Poland the official registers of terrain related objects have been undergoing modernisation. This modernisation focuses on the safety and protection of the rights to properties, increasing the efficiency of databases and the quality of data, as well as increasing the efficiency of planning and land management. The advanced technologies, such as CAD, GIS or DBMS, make it possible to build a digital terrain model (DTM) followed by a visualisation of surface objects, such as parcel boundaries or building outlines, in 3D. Modern relational databases and CAD tools also allow reconstruction of real estate state from any moment in history, registered in the database.

3D+time Cadastre, possibility of implementation in Poland

Modernization of the land and buildings cadastre is a set of actions aimed at improving the quality of data collected there. Application in the process of modernization of the sources of information from the land surveying, gives fully satisfactory results. On the other hand the use of photogrammetric measurements is the solution more economical in terms of financial and time. However, there is a danger of obtaining the results which do not meet the standards of accuracy of the border points position. The paper presents an example of the results of the influence of the process of modernizing the land and buildings cadastre for the areas where the source material are cadastral maps in the scale 1: 2000, created on the basis of photomaps or cadastral maps in the scale 1: 2880. An assessment of the suitability of these materials in the process of modernization and their impact on the current form of the land and building cadastre as a public register was made.

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Legal and Technical Aspects of Modernization of Land and Buildings Cadastre in Selected Area

Topological correctness of objects is an issue demanding solution in all undertakings related to the creation spatial databases. This article presents the technology for detection and elimination of topological errors in official databases (real estate cadastres, Land Parcel Identification System (LPIS)). The method for working on virtual objects in computer aided design (CAD) environment has been developed. This method can be successfully used for spatial databases, where large numbers of objects are elaborated. The suggested algorithm for verifying the topological correctness of surface objects was implemented in the years 2010–11, with the update of LPIS system databases, carried out by the Ministry of Agriculture in Poland. This technology received positive assessment in the course of the works undertaken.

Verification technology for topological errors in official databases with case study in Poland

Topological correctness of objects is a problem that needs solving in every project related to the development and updating of spatial databases. This problem can be solved using contemporary GIS software. However, the GIS systems, while working on large volumes of data, tend to be inefficient in editing separated elementary areas (parcels, non-eligible areas) which are presented in the form of objects. An alternative to GIS systems can be the development of a CAD software based technology. The article presents the technology of detection and automatic elimination of topological errors related to a lack of consistency in the official Land Parcel Identification System databases. The developed methodology operates on virtual objects in a CAD software environment. It can be freely used on outdated databases, which contain very large numbers of objects. This technology was used on a test object, made available by a Government Agency. The developed methodology allowed for an automatic correction of errors that...

Marek Ślusarski

Papers

3D+time Cadastre, possibility of implementation in Poland

Legal and Technical Aspects of Modernization of Land and Buildings Cadastre in Selected Area

Verification technology for topological errors in official databases with case study in Poland

Database inconsistency errors correction, on example of LPIS databases in Poland

Geoinformation technology and data models