Todd D. Fagin

Persistence and habitat associations of Purple Martin roosts quantified via weather surveillance radar

ContextWeather surveillance radars (WSR) have been used to locate roost sites used by Purple Martins (Progne subis) for decades. Improvements in radar data processing and accessibility now make it possible to monitor roosts over a broad spatial scale.ObjectivesWe sought to locate all of the Purple Martin roosts in North America and to use the data to evaluate (1) the land cover types associated with roosts (2) relationships among roost persistence, land cover type, and regional population trends.MethodsWe used mosaicked images of radar reflectivity based on the NEXRAD WSR network to locate 234 Purple Martin roosts that were active between 2009 and 2014. Of these roosts, we ground-truthed a subset of 57 with site visits and reports from citizen scientists. We assigned roosts to different classes based on local land cover, and used a variety of statistical and spatial analyses to address the objectives listed above.ResultsRoosts were mainly associated with forest, cropland, urban, and water land cover types, with cropland being the most common. There was an apparent preference for urban sites, and urban roosts were associated with the high year-to-year persistence. We found no correlation between roost persistence and regional population trends in data from the North American Breeding Bird Survey (BBS).ConclusionsAlthough they use a diverse array of roosting habitats, urban roosting areas appear to be increasingly important for Purple Martins. Persistence of urban roosts was high, which aligns with the species’ unique natural history and its association with human societies.

GIS Course Planning: A Comparison of Syllabi at US College and Universities

Despite the enormous growth of college courses dealing with spatial information, curriculum planning involving geographic information science (GIS) courses and programs has received little attention within the GIS literature. As the number and variety of GIS courses expands, so too does the importance of both systematic and inclusive planning and campus-wide coordination. In this article we explore course plan- ning through an exploration of 312 GIS course syllabi used at US colleges and universities with the goal of characterizing the degree to which learning resources, student evaluation methods, and course topics have become standardized across institution types, academic levels, and disciplines. Our findings reveal a consensus in the use of GIS software across courses but no similar agreement in the use of textbooks. Hands-on activities were used as evaluation methods in nearly every course in the sample regardless of institution type or academic level. However, quizzes, tests and final exams were used more often in com- munity colleges while papers and projects were used more frequently in four-year and comprehensive research universities. The frequency of topic categories listed on syllabi was relatively consistent across institutions, academic levels and disciplines with a few topics such as vector analytic operations, data models, and data creation/acquisition/editing included on more than 50% of syllabi.

Hard and Soft Skills in Preparing GIS Professionals: Comparing Perceptions of Employers and Educators

Organizations that hire GIS professionals look for entry-level employees with specialized technical skills but also other competencies such as effective communication and a capacity to think critically and creatively. Indeed, the success of GIS projects and initiatives often depends on individuals who possess a combination of specialized GIS skills and more general competencies that influence their ability to collaborate and manage resources. This article presents findings from a survey of GIS employers and educators concerning the importance of hard and soft skills among entry-level GIS professionals. A key finding is the high level of consistency in ratings assigned by employers and educators concerning hard skills such as data editing and GIS analysis and soft skills including problem solving and adaptability. However, the groups were less similar in ratings assigned to data capture skills, project management, and written/verbal skills. GIS qualifications were also compared, revealing a greater emphasis on internships among educators and higher ratings assigned to academic GIS certificates among employers.

Mapping Annual Forest Cover in Sub-Humid and Semi-Arid Regions through Analysis of Landsat and PALSAR Imagery

Accurately mapping the spatial distribution of forests in sub-humid to semi-arid regions over time is important for forest management but a challenging task. Relatively large uncertainties still exist in the spatial distribution of forests and forest changes in the sub-humid and semi-arid regions. Numerous publications have used either optical or synthetic aperture radar (SAR) remote sensing imagery, but the resultant forest cover maps often have large errors. In this study, we propose a pixel- and rule-based algorithm to identify and map annual forests from 2007 to 2010 in Oklahoma, USA, a transitional region with various climates and landscapes, using the integration of the L-band Advanced Land Observation Satellite (ALOS) PALSAR Fine Beam Dual Polarization (FBD) mosaic dataset and Landsat images. The overall accuracy and Kappa coefficient of the PALSAR/Landsat forest map were about 88.2% and 0.75 in 2010, with the user and producer accuracy about 93.4% and 75.7%, based on the 3270 random ground plots collected in 2012 and 2013. Compared with the forest products from Japan Aerospace Exploration Agency (JAXA), National Land Cover Database (NLCD), Oklahoma Ecological Systems Map (OKESM) and Oklahoma Forest Resource Assessment (OKFRA), the PALSAR/Landsat forest map showed great improvement. The area of the PALSAR/Landsat forest was about 40,149 km2 in 2010, which was close to the area from OKFRA (40,468 km2), but much larger than those from JAXA (32,403 km2) and NLCD (37,628 km2). We analyzed annual forest cover dynamics, and the results show extensive forest cover loss (2761 km2, 6.9% of the total forest area in 2010) and gain (3630 km2, 9.0%) in southeast and central Oklahoma, and the total area of forests increased by 684 km2 from 2007 to 2010. This study clearly demonstrates the potential of data fusion between PALSAR and Landsat images for mapping annual forest cover dynamics in sub-humid to semi-arid regions, and the resultant forest maps would be helpful to forest management.

Land tenure and landscape change: a comparison of public-private lands in the southern High Plains

IntroductionLong-term drought in the southern Great Plains increases the vulnerability of coupled human-environment systems at a variety of scales. Developing better understandings of the dynamics at regional scales will become increasingly important as long-established land-use regimes break down in the face of climate change, resource depletion, and evolving governance. To demonstrate differential vulnerability during drought periods, this study hypothesized that observed increases in woody vegetation in grasslands would vary across land-tenure regimes. We argue that differences in State Trust Land governance, in part, lead to differential land management practices that contribute to landscape change.MethodsThe study area encompasses adjacent counties, Cimarron County in Oklahoma and Union County in New Mexico, with similar climate variability and agricultural economies. We analyzed National Land Cover Database (NLCD) land-cover maps from 1992 and 2011 to assess changes in landscape composition and structure between 1992 and 2011.ResultsDuring both years under consideration, each county in the study region, across various land-tenure regimes, was dominated by herbaceous vegetation. However, there were changes in both composition and structure across the whole study area, in particular losses of herbaceous vegetation and increases in woody vegetation. The greatest gains in woody vegetation occurred in State Trust Lands of Cimarron County. Overall, the data suggest a fragmentation of herbaceous vegetation and a coalescing of shrubland patches.ConclusionsResearch about the influence of land tenure on land management decisions, specifically the role of State Trust Land leases in overgrazing, informs the broader context of drought management in the southern Great Plains. Recommendations include continued research to highlight the specific mechanisms of land-tenure governance that drive landscape change.

A Landscape in Transition: The Arbuckle Mountains, 1870 to 1898

An understanding of the contemporary biogeography of a region must be predicated not only on the current environmental conditions that influence species distributions but also on historical factors including anthropogenic disturbance regimes. Increasingly, researchers are using historical data, such as the Public Land Survey System (PLSS) records, to create baselines from which subsequent biogeographic changes can be gauged. The present-day state of Oklahoma is unique in that two separate PLSS surveys were conducted in the state during a relatively short time span. We compare these two historical data sets, from the 1870s and 1890s, respectively, to quantify changes in landscape structure and woody plant assemblages corresponding to rapid demographic changes occurring within the Arbuckle Mountains in Oklahoma. During this period, the PLSS data show a landscape that became increasingly fragmented, as well as differences in stand composition and density. The documentation of these important historical anthropogenic changes occurring on the western fringes of the eastern deciduous forest could serve as a valuable guide for conservation and restoration initiatives.

The Pulse of the Planet: Measuring and Interpreting Phenology of Avian Migration

Changing phenology of bird migration has become a flagship example of the biological impacts of climate change. Bird migration phenology data come from a limited number of time series in idiosyncratic locations. Improved understanding of these relationships requires new data collected in a standardized method that spans spatial and temporal scales. We used weather surveillance radar data and eBird data to show that it is feasible to measure bird migration phenology from local to regional scales and that these data provide geographically informative and temporally consistent patterns of migration phenology. We examine both a single species (Purple Martin) case and widespread nocturnal songbird migration. We also analyzed patterns in potential environmental cues that migrants might use to adjust their phenology en route. These analyses suggest that temperature does form a thermal wave that is a plausible cue for adjusting migration timing, but that the Normalized Difference Vegetation Index (NDVI) as a measure of the start-of-spring does not produce a green wave that would be informative to migrants for gauging seasonal phenology. This result calls into question the use of vegetation indices to understand how migrants adjust their timing en route.

Spectral Angle Mapper and aeromagnetic data integration for gold-associated alteration zone mapping: a case study for the Central Eastern Desert Egypt

ABSTRACT The Spectral Angle Mapper (SAM) classification technique is integrated with the surface structure and aeromagnetic data to map the potential gold mineralization sites associated within alteration zones in Central Eastern Desert (CED), Egypt. The surface reflectances of the Enhanced Thematic Mapper Plus (ETM+) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data were classified using the SAM classifier. Five spectral reflectance curves of the alteration minerals (haematite, illite, kaolinite, chlorite, and quartz) were utilized as end-members for the SAM classification. The surface lineation, and shear zone systems were delineated using ETM+ bands. The deep-seated faults were defined using the Euler deconvolution filter on the gridded aeromagnetic data. The magnetic data analysis inferred the subsurface structural depths range from 500 m to 2000 m. Geographic information system (GIS) overlaying operation was performed using the surface lineation and the subsurface faults layers to identify the structural continuity and to extract the possible migratory pathways of the hydrothermal solutions. Within Multiple Criteria Decision Analysis (MCDA), fuzzy membership operations were applied to identify the prospective alteration sites. The mapped results were compared with global positioning system (GPS) locations of existing alteration zones. The current proposed mapping method is considered a robust tool for decision-making and potential site selection technique for further mineral exploration in CED.