Geographic Information System-based Model Research Articles

CommunityViz-Based Prototype Model for Assessing Development Impacts in a Naturalized Floodplain—EmiquonViz

We present a prototype spreadsheet-based and geographic information system-based model, EmiquonViz, developed to examine the economic, fiscal, and social impacts of development. The model is designed to facilitate examination of hypothetical scenarios related to introducing recreational use and siting a lodging facility within a naturalized floodplain. In building the model we draw on the ongoing floodplain naturalization efforts in the middle reach of the Illinois River and assume that the new development would amount to a park of at least regional and possibly state stature; it would, therefore, attract nonlocal visitors and generate impacts on the local communities. EmiquonViz is implemented in ArcView 3.3 using the CommunityViz Scenario Constructor extension. Its purpose is to serve as a decision-making tool for planners and other community members concerned with the impact of recreational and tourism-related activities.

00/02750 A Geographic Information System-based modeling system for evaluating the cost of delivered energy crop feedstock

00/02750 A Geographic Information System-based modeling system for evaluating the cost of delivered energy crop feedstock

Models of low temperature and high irradiance and their application to explaining the risk of seedling mortality

Low temperature during the growing season is known to be a leading cause of stress and damage to tree seedlings and interactive effects with high irradiance have been recognised as enhancing the damage. Spatial variation in low temperature and irradiance for mountainous terrain was, therefore, hypothesised to give rise to spatially variable potential for regeneration of tree seedlings and expansion of forest. Combined exposure to low temperature and high irradiance appears most likely on clear mornings following frosty nights. Geographic information system-based models of the spatial variation in minimum air temperature over clear-felled terrain and potentially intercepted direct radiation energy were constructed and were used together with measured values of minimum air temperature to explain observed spatial variation in mortality rates for planted tree seedlings in central Sweden. A local-scale multiple regression model explained 78% of the measured spatial variability in minimum air temperature over 625 km 2 and a corresponding, but univariate, microscale model explained 54% of the measured spatial variation in minimum air temperature over 4 ha. Multiple logistic regression models for the mortality rates of seedlings showed there was no significant effect of potentially intercepted amounts of direct radiation energy during the morning for either scale. There was, however, a significant effect ( p<0.0001) of measured minimum air temperature on seedling mortality rates for the microscale study, but no corresponding significant effect for the local-scale study. This confirms that low temperature is an important determinant for seedling mortality. It is likely that other factors than low temperature may be important. However, our results indicate that effects of local-scale variability in minimum air temperature, represented by the minimum air temperature at standard height above the ground (1.8 m), may be over-shadowed by minimum air temperature variability at seedling height in complex terrain. This has implications for the use of standard meteorological data for studies into the responses of plants to abiotic factors.

A Geographic Information System-based modeling system for evaluating the cost of delivered energy crop feedstock

The use of Geographic Information Systems (GIS) for understanding the geographic context of bioenergy supplies is discussed and a regional-scale, GIS-based modeling system for estimating potential biomass supplies from energy crops is described. While GIS models can capture geographic variation that may influence biomass costs and supplies, GIS models are not likely to handle uncertainty well and are often limited by the lack of spatially explicit data. The presented modeling system estimates the costs and environmental implications of supplying specified amounts of energy crop feedstock across a state. The system considers where energy crops could be grown, the spatial variability in their yield, and transportation costs associated with acquiring feedstock for an energy facility. The modeling system was used to estimate potential switchgrass costs and supplies in eleven US states. Transportation costs increased with increased facility demand and were lowest in Iowa, North Dakota and South Dakota and highest in South Carolina, Missouri, Georgia, and Alabama. Farmgate feedstock costs were lowest in Alabama, North Dakota and South Dakota and highest in Iowa and Nebraska. Across the eleven states, delivered feedstock costs ranged from $33 to $55/dry tonne to supply a facility requiring 100,000 tonne/yr. Delivered feedstock costs for a 630,000 tonne/yr facility ranged from $36 to $58/dry tonne.

Comparison of spatial modelling and field evidence of glacier/permafrost relations in an Alpine permafrost environment

AbstractAccording to geographic information system-based modelling, the Muragl glacier forefield situated in the St Moritz area, eastern Swiss Alps, lies in a potential permafrost area. As an attempt to verify spatial modelling, BTS (bottom temperature of the winter snow cover) measurements, geoelectrical soundings and geomorphological mapping were carried out in order to investigate the present-day permafrost and ground-ice distribution in this forefield. Recent geomorphodynamic processes in the steep upper slopes of the cirque include small debris flows and several slides related to the occurrence of ground ice. The occurrence of fluted moraines and a well-developed push moraine provides geomorphological evidence for a complex thermal regime of the former Muragl glacier, with cold marginal parts frozen to the bed, and warm-based ice in more central parts where fluted moraines could develop. Details of the inferred glacier/permafrost interaction are difficult to interpret. The results of field measurements (BTS and geoelectrical soundings) in the recently deglaciated forefield indicate the local occurrence of permafrost in the forefield and in the push moraine. In most parts of the forefield, permafrost may be assumed to be a former subglacial occurrence. However, new permafrost formation in the recently deglaciated forefield cannot be excluded.

Geographic Information System-Based Transportation Forecast Model for Small Urbanized Areas

The geographic information system (GIS) has been demonstrated to be an effective tool for transportation forecasting and scenario analysis. Previous efforts have linked full-function GIS packages with transportation forecasting models. Tools developed to provide a modeling environment more appropriate for the technical knowledge level and budget requirements of small urban or rural areas are described. Specifically, the needs of metropolitan planning organizations and regional planning affiliations in Iowa were considered in the system design. A desktop mapping package, MAPINFO, is integrated with an urban transportation planning model, TRANPLAN, to provide an interface for network analysis. With the system, network modifications and changes representing alternative demand scenarios are made in the GIS environment, and data are exported to the TRANPLAN format, and, after analysis, returned to the GIS for effective presentation of results. User tools were tested and a case study demonstrating alternatives analysis and display capabilities is presented. Although developed and tested for Des Moines, the system can easily be transferred to other agencies to enhance transportation planning capabilities.