FOSS tools and applications for education in geospatial sciences

While the theory and implementation of geographic information systems (GIS) have a history of more than 50 years, the development of dedicated educational tools and applications in this field is more recent. This paper presents a free and open source software (FOSS) approach for education in the geospatial disciplines, which has been used over the last 20 years at two Italian universities. The motivations behind the choice of FOSS are discussed with respect to software availability and development, as well as educational material licensing. Following this philosophy, a wide range of educational tools have been developed, covering topics from numerical cartography and GIS principles to the specifics regarding different systems for the management and analysis of spatial data. Various courses have been implemented for diverse recipients, ranging from professional training workshops to PhD courses. Feedback from the students of those courses provides an invaluable assessment of the effectiveness of the approach, supplying at the same time directions for further improvement. Finally, lessons learned after 20 years are discussed, highlighting how the management of educational materials can be difficult even with a very open approach to licensing. Overall, the use of free and open source software for geospatial (FOSS4G) science provides a clear advantage over other approaches, not only simplifying software and data management, but also ensuring that all of the information related to system design and implementation is available

Relevance of the cell neighborhood size in landscape metrics evaluation and free or open source software implementations

Landscape metrics constitute one of the main tools for the study of the changes of the landscape and of the ecological structure of a region. The most popular software for landscape metrics evaluation is FRAGSTATS, which is free to use but does not have free or open source software (FOSS). Therefore, FOSS implementations, such as QGIS’s LecoS plugin and GRASS’ r.li modules suite, were developed. While metrics are defined in the same way, the “cell neighborhood” parameter, specifying the configuration of the moving window used for the analysis, is managed differently: FRAGSTATS can use values of 4 or 8 (8 is default), LecoS uses 8 and r.li 4. Tests were performed to evaluate the landscape metrics variability depending on the “cell neighborhood” values: some metrics, such as “edge density” and “landscape shape index”, do not change, other, for example “patch number”, “patch density”, and “mean patch area”, vary up to 100% for real maps and 500% for maps built to highlight this variation. A review of the scientific literature was carried out to check how often the value of the “cell neighborhood” parameter is explicitly declared. A method based on the “aggregation index” is proposed to estimate the effect of the uncertainty on the “cell neighborhood” parameter on landscape metrics for different map

Dataset of tree inventory and canopy structure in poplar plantations in Northern Italy

The dataset reports data collected in 38 square (50 x 50m) 0.25 ha plots representative of poplar plantations in Lombardy Region (Northern Italy), which were used to calibrate optical information derived from unmanned aerial vehicle (UAV) and satellite (Sentinel-2) sensors.In each plot, the diameter at breast height was measured using a caliper; height, stem and crown volume of each tree were then derived from diameter using allometric equations developed in an independent study. Additional canopy attributes (foliage and crown cover, crown porosity, leaf area index) were derived in each plot from 12-20 optical images collected using digital cover photography (DCP).The collected data allows characterizing the assessment of structure of these plantations, along with their variation over the rotation time. Canopy and crown data also enable the evaluation of optimal rotation and tree spacing, as well as the relationship between stand and canopy structure.The raw datasets consist of 2,591 records (trees) associated with inventory measurements and 616 records (images) associated with optical canopy measurements. An R code was also provided to calculate plot-level attributes from raw data.Dataset and associated metadata are freely available at http://dx.doi.org/10.17632/ycr7w5pvkt.1

Fruit availability for migratory birds: a GIS approach

Bird migration is a widely studied phenomenon, however many factors that influence migratory flows remain unknown or poorly understood. Food availability en route is particularly important for many species and can affect their migration success, pattern and timing but this relationship has not been addressed at a wide scale due to the lack of spatial models of food availability on the terrain. This work presents a GIS-database approach that combines spatial and non-spatial ecological information in order to map fruit availability from vegetation over time in the SE Alps, an important node of European migratory routes. We created a unique database that contains information on the presence and periods of fructification of 52 wild plants carrying berries and a series of original cartographic themes. The presence and coverage of the plant species was modelled with the geo-statistical method of the Gaussian Kernel, which was validated against the ground truth of field sampling data with a correct classification power above 80% in most cases. The highest fruit availability in the study area during September and October co-occurs with the peak of captures of berry eating birds. The maps created and distributed along this work can be useful to address more detailed studies about stopover sites as well as the spatial ecology of other fruit eating animals

The 1936 Italian Kingdom Forest Map reviewed: a dataset for landscape and ecological research

The recovery of the 1936 Italian Kingdom Forest Map (IKFM) (276 sheets 1:100,000) is described. It is a unique document that describes the forest extent and species composition for the whole of Italy. The original document is available in paper format using a datum and a map projection no longer in use, therefore it is not suitable for analysis using current digital tools. Therefore, this map has been firstly converted to a digital image, georeferenced and reprojected as a raster map in the official Italian datum; secondly, has been digitalized in vector format. This map provides historical, ecological and landscape information and fills a great temporal gap in those portions of Italy where landscape maps are available for some earlier periods. Its importance is extended to parts of Croatia, Slovenia and France. The technical problems faced in the recovery and transformation of the cartography into a usable format are described and discussed. A first data overview and analysis based on a test study, and comparisons with current national forest inventory data aimed to highlight potential and limits of IKFM are presented. The map is available on-line through a WebGIS at the address carta1936.dicam.unitn.i

Influence of image pixel resolution on canopy cover estimation in poplar plantations from field, aerial and satellite optical imagery

Accurate estimates of canopy cover (CC) are central for a wide range of forestry studies. As direct measurements are impractical, indirect optical methods have often been used to estimate CC from the complement of gap fraction measurements obtained with restricted-view sensors. In this short note we evaluated the influence of the image pixel resolution (ground sampling distance; GSD) on CC estimation in poplar plantations obtained from field (cover photography; GSD < 1 cm), unmanned aerial (UAV; GSD <10 cm) and satellite (Sentinel-2; GSD = 10 m) imagery. The trial was conducted in poplar tree plantations in Northern Italy, with varying age and canopy cover. Results indicated that the coarser resolution available from satellite data is suitable to obtain estimates of canopy cover, as compared with field measurements obtained from cover photography; therefore, S2 isrecommended for larger scale monitoring and routine assessment of canopy cover in poplar plantations. The higher resolution of UAV compared with Sentinel-2 allows finer assessment of canopy structure, which could also be used for calibrating metrics obtained from coarser-scale remote sensing products, avoiding the need of ground measurements

Analysis of Bird Flyways in 3D

Bird migration is a long studied phenomenon that involves animals moving back and forth from wintering sites and to reproductive grounds. Several studies have focused on identifying the timing, physiology and evolution of migration, but a spatial approach to understand the migratory routes is still an open challenge. Geographic Information Systems (GIS) can provide the tools to explore such a complicated issue. Birds usually move from the wintering sites to spring breeding grounds in multiple flights, stopping at intermediate sites to rest and refuel, being unable to cover the distance in a single travel. The choice of stopover sites by birds depends not only on their ecological features but also on their position and visibility along main migratory flyways. In this work, we calculated the possible migratory routes that minimize the distance covered or the elevation gaps for birds crossing the Southern Alps, simulating the flight within a network connecting potential stopover sites and other relevant point of passage, using the shortest path computation. Subsequently, we performed a visibility analysis along the identified flyways to understand which stopover sites, belonging to the Natura2000 network, were visible for a bird in an area with complex morphology. Data available from ringing stations confirm the selection or avoidance of some stopover sites based on their en route visibility. The knowledge of bird flyways and stopover sites has implications for conservation as well as for planning, especially for wind farms or other infrastructures

Nomen omen. Toponyms predict recolonization and extinction patterns for large carnivores

The names given to places are a legacy of the past distribution of animal and plant species. The hypothesis tested in this work is that the density of toponyms can be used to predict the range of two large and charismatic species over time: the wolf and the brown bear in Italy. Kernel density maps of the toponyms were created and different thresholds of density were overlapped with the present and the historical ranges for both species. The density level maps were tested with the Kappa statistics against available historical ranges for both species. The pattern of the density in toponyms overlapped with the pattern of contraction and expansion reported in literature for both species over time. The minimum historical distributions of wolves and brown bears occurred at the highest densities of toponyms (95% isopleth value) and, overall, the various kernels thresholds showed an excellent agreement with the historical maps with an average Kappa of 0.84 ± 0.5

Advertising value of the brown bear in the Italian Alps

In Italy, the reintroduction of the brown bear (Ursus arctos) has created conflicts with people because bears may damage livestock, crops, or honey farms. These damages—and their financial costs—are sometimes used as an argument by those who oppose the presence of this carnivore. Despite such damages, bears can provide economic benefits, such as attracting eco-tourists for bear-watching. The Advertising Value Equivalent was used to assess the value of the bears’ appearances in newscasts and documentaries from 2011 to 2015. The marketing value of the bear as a promoter largely exceeds the amount of reimbursements for damages. This method can be used to highlight the economic benefit that the bear can produce for a destination and contribute to complex discussions with managers and stakeholders