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The collared peccary (Pecari tajacu) is distributed from southwestern USA to northern Argentina; however, in some Argentinean localities it went extinct over 50 years ago. As part of a rewilding project, two peccary groups (one captive-bred family group and one mixed group formed by not genetically related individuals) were reintroduced to the Ibera National Park. Following the release, we monitored the movements of 16 individuals to obtain GPS locations every 100 min, for 6 months. We evaluated the individual’s spatial patterns by assessing site fidelity, home range changes, and habitat selection. Most members of the family group survived and established a home range whereas almost all members of the mixed group dispersed and did not survive. Using the Autocorrelated Kernel Density Estimator, the groups’ home range was 8.9 ± 1.7 km2 for the entire study period. In addition, individuals showed high fidelity to release site and a stable home range a few months after release. At larger scales (second order of selection), peccaries selected forested habitat and proximity to release site while at a smaller scale (third order of selection), they avoided grasslands. We highlight the importance of familiarity of individuals prior to release and provide recommendations for future reintroductions. Three years later, by September 2019, nine groups were established in the Ibera National Park and the abundance was over 45 individuals. This is the first post-release assessment of the movement patterns of collared peccaries in South America.

Thailand's decentralization policies have sought to increase urbanization and development in provinces outside Bangkok. Provincial and district government offices increasingly formulate local development strategies that draw on concepts of sustainability, livelihood rights, and market opportunities. Despite such local shifts in policy, urban sprawl has created environmental degradation and natural resource competition among different stakeholders within transitional rural-urban spaces. Furthermore, urban expansion has encumbered agrarian families' abilities to fully provision their households. This article examines how agrarian families in Thailand's northeastern (Isaan) region understand state development and urban encroachment and how these families reconfigure livelihood strategies and labor mobilities under changing sociopolitical and environmental conditions. The combination of Landsat data on urban encroachment and ethnographic exploration of the broader shifts in sociopolitical systems that valoriz...

Geographic information systems (GIS) have played an increasing role in spatial analysis of linguistic data, especially in geolinguistics and regional dialectology. In this study we collected lexical data on the Chiang Mai dialect from 500 informants and examined different variants of the words they used. Data points were interpolated using an ordinary kriging approach and an estimated surface of each variant was created from these sample points. The resulting surface was overlaid onto a topographic relief map and displayed in three dimensions to facilitate the exploration of spatial patterns between physical and social variables. Whereas many language atlases traditionally present dialect observations using point symbol maps, a 3-D interpolated map has proved to be a useful tool for visualizing cooccurrences of multiple variants of the same word at the same geographic location. This technique also allows linguists to examine a general trend of dialect variation in Chiang Mai, which might not be re...

The concentric zone model is one of the earliest models to explain how a city will grow based on its urban social structures. This model assumes an isotopic landscape, thus city expansion can grow in every direction, with some emphasis on extending social structures and the expense of commute times. This study seeks to understand if the presence of mass-transit routes in the city of Baltimore has modified the rounded shape of the concentric zone model and population distribution, as urban expansion has continued. To accomplish this, we explored a relationship between population density and travel-time-to-center (TTC). The expenditure in time a commuter must face to reach the urban center was calculated based on the availability of automobile transit routes using a geographic information system network analysis. We calculated a correlation coefficient between the variables so that the relationship could be explored. Results suggest a moderate negative relationship between TTC and population density...

In the current system, school bus stops in Howard County, Maryland are manually placed along the school bus routes based on safety, cost-efficiency, and many other variables. With such liberal placement, bus stops are sometimes placed unnecessarily. This issue is prevalent in many school districts and often results in needlessly close bus stop proximity. In this study, the authors implemented a GIS-based heuristic to assist school officials in optimizing their districts bus stop placement. They also estimated the proportion of county-wide bus stops that could be eliminated by this approach. Following the constraints determined by State and local guidelines, the ArcGIS Network Analyst Extension was used to identify unnecessary bus stops across the study area. The initial output was re-evaluated by school officials in order to determine if those bus stops would be eliminated. The results indicate that approximately 30% of the existing bus stops were marked as “candidates for elimination” by the GIS process. After a review of these candidates, it was determined that at least 15% of the total school bus stops could be eliminated. Statistical estimates lent credence to the benefit of a re-evaluation of these bus stops. The method developed in this study can easily be replicated. Hence, it may inspire other school systems to exercise the same approach. Additionally, the results provide a gateway for future studies in examining more efficient school bus routes with less travel time, as well as investigating how much the carbon footprint of school bus fleets can be reduced.

Research has indicated that Thailand's future economic growth and industrial expansion will be relocated to peri-urban locations and secondary cities throughout the kingdom. As industrial activities extend into and transform rural areas, incompatible land use patterns emerge and produce pressures on environmental resources. This research investigates the dynamic of peri-urban growth in Sung Noen District, Nakhon Ratchasima Province, Thailand. The study area represents a new-growth secondary city with one of the largest metropolitan populations for a city disconnected from Bangkok's extended metropolitan region. Our study aims to provide a systematic analysis of peri-urban change in this area. We use a hybrid classification scheme to examine multitemporal Landsat TM and Landsat ETMC data, coupled with geographic information systems analyses to help assess the loss of peri-urban land between 1990 and 2014. The result can serve as a guide to answer future research questions relating to sustainability and env...

“Empty forests” in which humans have driven large vertebrate species to extinction lack myriad direct and indirect species interactions. This may alter key ecosystem processes, including trophic cascades, disturbance regimes, and nutrient cycling. Past research concerning the effects of tropical forest defaunation mainly compared sites with an intact fauna with sites having degraded faunal communities. However, experimental studies on seedling demographics at individual sites, with the same abiotic and biotic conditions, over a long period of time are still scarce. In this research we conducted a 7-year experiment within a completely intact and pristine forest in Manu National Park, Peru to elucidate the effects of defaunation on tree seedling demographics and densities. We constructed semipermeable exclosures that prevented access of large terrestrial vertebrates, but allowed free passage of small- and medium-sized species. New tree seedlings taller than 5 cm were tagged and followed. Jolly–Seber mark-recapture models were used to estimate density, survival, and recruitment of seedlings. Seedling density in the exclosures continued to increase significantly after the first year of the study. Only during the first 2 years was seedling survival higher in the exclosures. The numbers of new recruits were consistently higher in exclosures when compared to open control plots throughout the study. In accord with increased density, survival, and recruitment in exclosure plots, we also observed increased understory vegetation cover. Our results suggest that defaunation can have long-term effects on seedling demographics and density, which could ultimately influence the composition and diversity of the canopy tree community.

The concept of ecosystem engineering has catalysed novel approaches and models for non-trophic species interactions and ecosystem functions. Ecosystem engineers physically modify abiotic and biotic environments, thereby creating new habitats that can be colonized by a new suite of species. In the Peruvian Amazonas, we tested whether peccaries (Tayassuidae) function as ecosystem engineers by creating and maintaining wallows. Such wallows could be critical aquatic habitats and breeding sites for anuran species during dry seasons. We compared hydroperiods of 21 peccary wallows and 13 naturally formed ponds across three dry seasons and found that wallows had a consistently higher mean water surface area than ponds. We also examined the pH, dissolved oxygen and temperature, and found no significant differences in these parameters between water bodies. Wallows had a significantly higher density of tadpoles, metamorphs and adult anurans, as well as higher β-diversity and species richness than ponds. This study not only provides the first systematic evidence of the ecosystem engineering processes of peccaries, but also reveals the positive consequences of such for anuran species.

This study implemented tactile interfaces with audio representations to convey spatial information on topographic maps. Two sound variables, pitch and duration, were incorporated with contour lines to represent various aspects of topographic features such as elevation, slope, profile, and landform. The effect of one sound variable (pitch) vs. a combination of two sound variables (pitch and duration) on topographic map interpretation was evaluated. Participants explored the tutorial through the iFeel mouse and answered a series of map quiz questions afterward. The results indicated that this approach provided a multisensory access to information, thus allowing them to explore and correctly answer questions pertaining to aspects of topographic maps. However, using one or two sound variables had almost the same effect in the slope, profile, and landform determination.

During 12 and 18 August 1999, severe thunderstorms produced damaging winds and hail that caused an estimated $50 million in damage to agriculture in west-central Illinois. Landsat-7 imagery was obtained to determine the arealextent of damage and produce a crop damage dollar estimate. The normalized difference vegetation index (NDVI) was calculated for images taken “before” and “after” the severe thunderstorm events in order to examine the changes in NDVI, or vegetation vigor. A differenced image was also produced by subtracting the NDVI of the two images. Landsat-7 data was found to be useful for identifying the areal extent of severe thunderstorm damage in west-central Illinois. In comparing the detection of damage produced by high winds and hail, it was found that hail damage was considerably easier to identify. This is due to the fact that large hail typically destroys the crops while high winds blow over corn plants that can remain rooted and survive. Additionally, county estimates of dollar ...