#Edicao de feicoes quantum gis driver#

Importantly, while species turnover (β-diversity) of native species increased with distance between nodes in the network, this was not the case for non-native species, indicating a much lower dispersal limitation of the latter. We found, however, contrasting patterns of native and non-native amphipod richness along the network, with headwater nodes representing refugia for native species and more downstream nodes being hotspots of biological invasions. Overall, species richness increased along the network from headwaters to the outlet nodes. We studied amphipod community diversity and structure in the upper 27,882-km2 drainage basin of the river Rhine in Central Europe, focusing on differences between native and non-native species. These networks not only define dispersal of native species, but also represent corridors of biological invasions, making understanding network topology effects on invasion dynamics and subsequent diversity patterns of high interest.

#Edicao de feicoes quantum gis driver#

It is especially seen as an important driver of the spatial structuring of biological communities in ecosystems that have intrinsic and general connectivity patterns, such as the universal dendritic structure of fluvial networks. Habitat connectivity crucially influences dispersal of organisms. Keywords: Equivalent Rectangle Method Double Buffer Method Positional Accuracy OSM. As a result, for the 1:25,000, 1:50,000, 1:100,000 and 1:250,000 scales, it was obtained, respectively, the PEC-PCD for the Equivalent Rectangle Method 'C', 'B', 'A' and 'A' and the PEC-PCD for the Double Buffer Method 'R', 'C', 'B' and 'A', where 'R' means that it has not achieved the minimum PEC-PCD classification. In the second stage, we evaluated the vector data of the OpenStreetMap (class of roads), with reference to a more accurate vector dataset produced for the Mapping of the State of Bahia.

In this step, it was verified that the shape of the feature and the direction of the displacement interfere in the results of both methods when compared to the traditional procedure of measurement of discrepancies by homologous points. Initially, an experiment was performed with features of known measurements, where the displacement of the homologous lines was controlled in azimuth and distance. These methods were compared in two steps. The second, Double Buffer Method applies a buffer on both lines and obtains the average discrepancy value based on the relation of the areas of the generated polygons. The first, Equivalent Rectangle Method, aims to determine the discrepancy by considering an equivalent rectangle for the polygon obtained from the two homologous lines. This work aims to compare the results of two methodologies that allow determining the average value of the discrepancies between linear features. Keywords: validation, topology, drainage network, quality control, QGIS, OpenStreetMap, OSM.Ĭurrently, in Brazil, for the assessment of the Positional Accuracy of non-point features (lines and polygons), there is no standard norm of execution. Among the encountered inconsistencies, the unconnected lines were more prominent, also indicating other problems in the completeness, which prevents the use of only automatic methods for the correction of topological inconsistencies. For the evaluation of the topological consistency, two tools were built for the QGIS that identify problems in the construction of the geometries and inconsistencies in the network, besides generating the drainage points (start point, end point, confluence, branch and attribute change point). In this context, this work was proposed to present fundamental concepts and topological rules for lines that comprise a drainage network in a case study applied to the features of the Waterways class originating from the OpenStreetMap to the watershed of the Alto Paraguai, in the Brazilian Pantanal. Topological consistency, an element of the logical consistency, aims to ascertain the compliance of topological rules in the dataset in a process known as topological validation. Logical consistency is a category of data quality elements that verifies if the data is coherent with logical and structural rules for real-world modeling. The International Organization for Standardization (ISO), on its 19,100 series, establishes the principles and elements of quality for geospatial data assessment.