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An overview about how UNIGIS offers distance-learning degree programs in geoinformatics around the world.
Trends in the Alaskan Bottom-Trawl Fishery from 1993-2015: A GIS-based Spatiotemporal Analysis
Carrie Elizabeth Steves
University of Southern California, United States of America
Using fishery-dependent observer data from National Marine Fisheries (NMFS) provides insight on the location and the intensity of bottom-trawl fishing effort, which can identify areas most exposed to fishing pressure. In this study, the spatial and temporal extent of Alaskan bottom-trawl fishing effort in the Bering Sea, Aleutian Islands, and Gulf of Alaska between 1993 and 2015 was explored within a space-time cube in ArcGIS Pro v1.4.1. The variables analyzed were number of hauls per area and total catch per area. Statistical techniques were used to examine spatiotemporal clustering in these data. Results indicate that fishing effort was non-randomly clustered over space and time (Moran’s I). A three-dimensional hot spot analysis shows which areas were most intensely fished and illustrates the long-term trends over the study period. The data were then compared with sea ice concentration to determine the effect of changing climate on fishing activity. Sea Ice had a limited effect on fishing effort spatial patterns, but certain areas in the Bering Sea exhibited increased fishing effort in years with less sea ice effect.
Automated Map Projection Selection for GIS
UNIGIS, United Kingdom
The selection of an appropriate map projection is a fundamental concern for cartographers and GIS users as the choice impacts the visualisation and analysis of geographic information. It is impossible to transform the curved surface of the Earth onto a two-dimensional plane without introducing distortion, and the number of available projections complicates the decision-making process. Selection of a suitable projection requires simultaneous consideration of several different factors such as the planned map purpose and the size, shape and location of the geographical area of interest, with the goal of assessing the projection distortion characteristics and parameters which best meet those criteria. There are cognitive difficulties in recognising and accounting for projection distortion, even for those with experience of the subject, so map projection selection continues to be a complicated and confusing process for many cartographers and GIS users.
Assessing Shrub and Tree Encroachment in Alpine Pastures from Airborne Laser Scanning Data
landplan AG, Schweiz
The forest area in alpine region is increasing. Agricultural land is abandoned – shrub and tree encroachment and reforestation are the consequences with negative impact on agriculture, biodiversity and tourism.
Assessing encroachment on agricultural land from Airborne Laser Scanning (ALS) data was tested in three study areas in Switzerland. The results of the data evaluation were compared with those for manually collected data from the interpretation of orthophotos. The evaluation indicated when a higher point density was available, the detection rate for areas with shrub and tree encroachment was also higher. The workflow using the Vertical Complexity Index (VCI) turned out to be robust for both large areas and large datasets. The accuracy levels achieved in this study for the encroachment index may provide a solid basis for prioritizing certain areas for projects that aim to limit the process of reforestation.