International Journal of Health Geographics

Aliya Pardhan-Ali, Olaf Berke, Jeff Wilson, Victoria L Edge, Chris Furgal, Richard Reid-Smith, Maria Santos, and Scott A McEwen

“Background: This is the first study to describe the geographical and temporal distribution of notifiable gastrointestinal illness (NGI) in the Northwest Territories (NWT), Canada. Understanding the distribution of NGI in space and time is important for identifying communities at high risk. Using data derived from the Northwest Territories Communicable Disease Registry (NWT CDR), a number of spatial and temporal techniques were used to explore and analyze NGI incidence from the years 1991 to 2008. Relative risk mapping was used to investigate the variation of disease risk. Scan test statistics were applied to conduct cluster identification in space, time and space-time. Seasonal decomposition of the time series was used to assess seasonal variation and trends in the data.

Spatial relative risk function for NGI.

“Results: There was geographic variability in the rates of NGI with higher notifications in the south compared to the north. Incidence of NGI exhibited seasonality with peaks in the fall months for most years. Two possible outbreaks were detected in the fall of 1995 and 2001, one of which coincided with a previously recognized outbreak. Overall, incidence of NGI fluctuated from 1991 to 2001 followed by a tendency for rates to decrease from 2002 to 2008.

“Conclusions: The distribution of NGI notifications varied widely according to geographic region, season and year. While the analyses highlighted a possible bias in the surveillance data, this information is beneficial for generating hypotheses about risk factors for infection.”

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Kirak Hong, Marco Voelz, Venu Govindaraju, Bharat Jayaraman, and Umakishore Ramachandran

“Cameras are becoming ubiquitous. Technological advances and the low cost of such sensors enable deployment of large-scale camera networks in metropolises such as London and New York. Applications such as video-base surveillance and emergency response that exploit such camera networks are continuous, data intensive, and dynamic in terms of resource requirements. Common anomalies in such application spaces include authorized personnel moving into unauthorized spaces and checking the movement of suspicious individuals as they move through the spaces. High level goal in such applications include catching such anomalies in real time and reducing collateral damage.

An example of how a spatio-temporal filter may be designed to prune the search space of signatures to be compared using the time and space attributes of the generated signature

“A well-known technique for meeting this high level goal is spatio-temporal analysis. This is an inferencing technique employed by domain experts (e.g., vision researchers) to answer queries such as show the track of person A in the last 30 minutes. Performing spatio-temporal analysis in real-time for a large-scale camera network is challenging. It involves continuously capturing images from distributed cameras, analyzing the images to detect and track objects of interest in the field of view of the cameras, generating an event by comparing the signature of a detected object against a database of known signatures, and maintaining a state transition table indexed by time that shows the spatio-temporal evolution of people movement through the distributed spaces. In this paper, we propose a distributed system architecture to address these challenges. We make the following contributions: (a) present the design choices for real-time spatio-temporal analysis with a view to supporting scalability (in terms of number of cameras, event rate, and known targets), (b) develop heuristics for pruning the event generation phase of spatio-temporal analysis, and (c) implement and evaluate the different design choices in a distributed system to show the scalability of our distributed system architecture.”

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American Journal of Preventive Medicine

“Background: The childhood obesity epidemic is a current public health priority in many countries, and the consumption of fast food has been associated with obesity.

“Purpose: This study aims to assess the relationship between fast-food consumption and obesity as well as the relationship between fast-food outlet access and consumption in a cohort of United Kingdom teenagers.

“Methods: A weighted accessibility score of the number of fast-food outlets within a 1-km network buffer of the participant’s residence at age 13 years was calculated. Geographically weighted regression was used to assess the relationships between fast-food consumption at age 13 years and weight status at ages 13 and 15 years, and separately between fast-food accessibility and consumption. Data were collected from 2004 to 2008.

Results of geographically weighted regression model of fast-food consumption; local coefficients with t-value contours

“Results: The consumption of fast food was associated with a higher BMI SD score (^^0.08, 95% CI^0.03, 0.14); higher body fat percentage (^^2.06, 95% CI^1.33, 2.79); and increased odds of being obese (OR^1.23, 95% CI^1.02, 1.49). All these relationships were stationary and did not vary over space in the study area. The relationship between the accessibility of outlets and consumption did vary over space, with some areas (more rural areas) showing that increased accessibility was associated with consumption, whereas in some urban areas increased accessibility was associated with lack of consumption.

“Conclusions: There is continued need for nutritional education regarding fast food, but public health interventions that place restrictions on the location of fast-food outlets may not uniformly decrease consumption.”

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Sven Lautenbach, Ralf Seppelt, Juliane Liebscher, and Carsten F. Dormann

“Pollination is a well-studied and at the same time a threatened ecosystem service. A significant part of global crop production depends on or profits from pollination by animals. Using detailed information on global crop yields of 60 pollination dependent or profiting crops, we provide a map of global pollination benefits on a 5′ by 5′ latitude-longitude grid. The current spatial pattern of pollination benefits is only partly correlated with climate variables and the distribution of cropland.

Global map of pollination benefits for soybeans

“The resulting map of pollination benefits identifies hot spots of pollination benefits at sufficient detail to guide political decisions on where to protect pollination services by investing in structural diversity of land use. Additionally, we investigated the vulnerability of the national economies with respect to potential decline of pollination services as the portion of the (agricultural) economy depending on pollination benefits. While the general dependency of the agricultural economy on pollination seems to be stable from 1993 until 2009, we see increases in producer prices for pollination dependent crops, which we interpret as an early warning signal for a conflict between pollination service and other land uses at the global scale. Our spatially explicit analysis of global pollination benefit points to hot spots for the generation of pollination benefits and can serve as a base for further planning of land use, protection sites and agricultural policies for maintaining pollination services.”

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Computers & Geosciences

Chester W. Jackson Jr., Clark R. Alexander, and David M.Bush

“The AMBUR (Analyzing Moving Boundaries Using R) package for the R software environment provides a collection of functions for assisting with analyzing and visualizing historical shoreline change. The package allows import and export of geospatial data in ESRI shapefile format, which is compatible with most commercial and open-source GIS software. The ‘‘baseline and transect’’ method is the primary technique used to quantify distances and rates of shoreline movement, and to detect classification changes across time. Along with the traditional ‘‘perpendicular’’ transect method, two new transect methods, ‘‘near’’ and ‘‘filtered,’’ assist with quantifying changes along curved shorelines that are problematic for perpendicular transect methods. Output from the analyses includes data tables, graphics, and geospatial data, which are useful in rapidly assessing trends and potential errors in the dataset.

Forecasted shoreline position for the year 2056 based on the linear regression rates (LRR) of shoreline change calculated at each transect. The orientations of filtered transects were used to project future shoreline movement. Other shoreline change rate calculation models, such as EPR and WLR, can also be used to forecast potential shoreline positions.

“A forecasting function also allows the user to estimate the future location of the shoreline and store the results in a shapefile. Other utilities and tools provided in the package assist with preparing and manipulating geospatial data, error checking, and generating supporting graphics and shapefiles. The package can be customized to perform additional statistical, graphical, and geospatial functions, and, it is capable of analyzing the movement of any boundary (e.g., shorelines, glacier terminus, fire edge, and marine and terrestrial ecozones).”

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Transactions in GIS

Germana Manca and Kevin Curtin

“Although defining geographic regions for analysis can be a complex exercise, involving both physical and human geographic perspectives, employing both qualitative and quantitative data, and integrating a wide range of social, economic, and political factors, it is frequently a necessary exercise in the pursuit of regional development. This article presents a method for modeling and delineating regions with fuzzy analysis for the purpose of regional development. A review of the literature regarding fuzzy analysis is provided, which demonstrates that this method is both novel and necessary. An application of this method is described in the context of the Sardinian Geopark.

Vegetation change from 1997 to 2006 based on cross tabulation analysis

“The fuzzy clustering analysis demonstrates how combinations of factors can inform decisions regarding where and how to initiate or continue regional development efforts. Suggestions for improvements and extensions to this process are provided.”

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American Journal of Preventive Medicine

“Background: Physical activity is an essential element in reducing the prevalence of obesity, but much is unknown about the intensity and location of physical activity among youth—this is important because adolescent health behaviors are predictive of behaviors in adults.

“Purpose: This study aims to identify the locations where youth moderate-to-vigorous physical activity (MVPA) occurs, and to examine how MVPA varies according to urbanicity (urban, suburban, rural).

“Methods: Participants included adolescent students (N 380, aged 12–16 years) from Halifax, Nova Scotia. Locations of MVPA were measured using accelerometers and GPS data loggers for up to 7 days. Specialized software was developed to integrate and process the data. Frequencies of MVPA by location were determined, and differences in MVPA were assessed for association with urbanicity.

Postprocessing of the GPS data using the GAP

“Results: Active commuting accounted for the largest proportion of time in MVPA among urban and suburban students. Rural students achieved most MVPA at school. Other residential locations, shopping centers, and green spaces accounted for a majority of the remaining MVPA. Minutes in MVPA varied significantly overall (196.6 163.8, 84.9 103.2, 81.7 98.2); at school (45.7 45.2, 18.6 28.0, 29.8 39.7); while commuting (110.3 107.1, 31.5 55.2, 19.5 39.7); and at other activity locations (19.7 27.1, 14.8 26.8, 12.0 22.1) and by urbanicity.

“Conclusions: Findings reveal that the journeys between locations are as important as home and school settings in contributing to greater MVPA in adolescent youth. The relative importance of context as a contributor to MVPA varies with urbanicity. Combining actimetry and GPS data provides a precise link between physical activity measurements and contexts of the built environment.”

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Maarten van Zonneveld, Xavier Scheldeman, Pilar Escribano, María A. Viruel, Patrick Van Damme, Willman Garcia, César Tapia, José Romero, Manuel Sigueñas, and José I. Hormaza

“There is a growing call for inventories that evaluate geographic patterns in diversity of plant genetic resources maintained on farm and in species’ natural populations in order to enhance their use and conservation. Such evaluations are relevant for useful tropical and subtropical tree species, as many of these species are still undomesticated, or in incipient stages of domestication and local populations can offer yet-unknown traits of high value to further domestication. For many outcrossing species, such as most trees, inbreeding depression can be an issue, and genetic diversity is important to sustain local production. Diversity is also crucial for species to adapt to environmental changes.

Allelic richness corrected for sample size by using rarefaction.

“This paper explores the possibilities of incorporating molecular marker data into Geographic Information Systems (GIS) to allow visualization and better understanding of spatial patterns of genetic diversity as a key input to optimize conservation and use of plant genetic resources, based on a case study of cherimoya (Annona cherimola Mill.), a Neotropical fruit tree species. We present spatial analyses to (1) improve the understanding of spatial distribution of genetic diversity of cherimoya natural stands and cultivated trees in Ecuador, Bolivia and Peru based on microsatellite molecular markers (SSRs); and (2) formulate optimal conservation strategies by revealing priority areas for in situ conservation, and identifying existing diversity gaps in ex situ collections. We found high levels of allelic richness, locally common alleles and expected heterozygosity in cherimoya’s putative centre of origin, southern Ecuador and northern Peru, whereas levels of diversity in southern Peru and especially in Bolivia were significantly lower. The application of GIS on a large microsatellite dataset allows a more detailed prioritization of areas for in situ conservation and targeted collection across the Andean distribution range of cherimoya than previous studies could do, i.e. at province and department level in Ecuador and Peru, respectively.”

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Computers, Environment and Urban Systems

Eric M. Delmelle, Shuping Li, and Alan T. Murray

“Highlights:

• A Spatial Interaction Coverage (SIC) model is used for transit planning.
• SIC presents an alternative modeling tool to increase system efficiency while maintaining suitable access coverage.
• Model parameters (access distance and facility attraction) are calibrated through consultations with local transit planners.
• Simulated annealing heuristic is developed within a GIS to solve this non-linear problem.

“Transit planners are often faced with a tradeoff between improving accessibility through the addition of stops while simultaneously increasing efficiency so that destinations can be reached in a reasonable amount of time. In this paper, we propose the development of an optimization framework integrated within a Geographical Information System (GIS) for addressing this specific problem. Our proposed modeling framework departs from well-known facility location coverage models by considering both the impact of walking distance from an individual residential location to a stop and the transit facility attractiveness (ease to cross, number of destinations served). Integration within a GIS environment is accomplished using a simulated annealing heuristic. An example on an inbound urban bus route illustrates the utility of the approach for transit planning, using model parameters developed in collaboration with local transit agencies.”

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Journal of Environmental Management

Francisco Rodríguez y Silva, Juan Ramón Molina, Armando González-Cabán, and Miguel Ángel Herrera Machuca

“The temporalespatial planning of activities for a territorial fire management program requires knowing the value of forest ecosystems. In this paper we extend to and apply the economic valuation principle to the concept of economic vulnerability and present a methodology for the economic valuation of the forest production ecosystems. The forest vulnerability is analyzed from criteria intrinsically associated to the forest characterization, and to the potential behavior of surface fires.

Timber resources vulnerability for the Córdoba Province.

“Integrating a mapping process of fire potential and analytical valuation algorithms facilitates the implementation of fire prevention planning. The availability of cartography of economic vulnerability of the forest ecosystems is fundamental for budget optimization, and to help in the decision making process.”

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