Day: July 9, 2010

Modeling and Mapping Soil Infiltration Rates in Dane County, WI

/ Matt Artz

2010 ESRI Southeast Regional User Group Conference

Kathleen Arrington and Steve Ventura

“We have developed and evaluated a model of soil infiltration rates in Dane County, WI. The maps generated from this analysis can be used for local to regional scale land use planning, building on previous RGIS-supported technology transfer to local governments. The rates at which precipitation moves into soil and recharges groundwater aquifers is spatially variable, depending on several soil properties such as texture and structure. Land use activities also influence soil infiltration through a direct effect on surface land cover and long term effects on soil properties. In areas that depend on groundwater for potable water supplies or irrigation, planners and developers should be cognizant of potential impacts of land use changes on groundwater supplies. To do this, they need reliable models for predicting soil infiltration rates coupled with spatial extrapolations, for example, maps depicting critical groundwater recharge. An empirical model of soil infiltration rate (a pedotransfer function) was developed through detailed measurements at 50 sites throughout Dane County. A large-frame infiltrometer was used to establish steady-state infiltration rates. Soil properties, including texture, bulk density and organic matter were measured at each site, along with site conditions such as land use and topography. Regression based techniques were used to determine the best combination of soil and other properties to predict infiltration rates. This locally derived model was a substantial improvement over predictions based on soil properties alone and over general models. The best model of soil infiltration rate was used to predict rates at unsampled locations, based on texture (percent sand), bulk density, and land cover. Because the grain (spatial resolution) of land cover data is much finer than the soil survey (which is otherwise the sole basis for predicting infiltration), the spatial acuity of the ensuing maps was a substantial improvement.”

The History and Development of the Theory and Practice of Cybercartography

/ Matt Artz / 1 Comment

International Journal of Digital Earth, Volume 3, Issue 1 March 2010 , pages 2 – 15

D.R. Fraser Taylor and Stephanie Pyne

“This paper describes the development of cybercartography since the introduction of the term in 1997. Although the origins of cybercartography were largely conceptual in nature, the evolution of cybercartography to date has been an iterative process reflecting the creative interplay between theory and practice. A major step forward was made in 2002 when the Geomatics and Cartographic Research Centre at Carleton University received a $2.5 million grant from the Social Sciences and Humanities Research Council of Canada to explore the utility of cybercartography to what was described as the New Economy. By 2006, the interaction between theory and practice had led to considerable advances in cybercartography as a holistic, location-based concept and two new cybercartographic products, the Cybercartographic Atlas of Antarctica and the Cybercartographic Atlas of Canada’s Trade with the World, were produced. Between 2006 and 2009, cybercartography was further developed as a result of interaction with indigenous communities, especially in Canada’s north and new interactive atlases such as the Kitikmeot Place Names Atlas and the Community Atlas of Arctic Bay were created in cooperation with the communities involved. The Nunaliit Cybercartographic Atlas Framework, built using open source software and open specifications and standards, was developed to facilitate direct input to these atlases. Cybercartography is now entering a new phase in both theory and practice building on a recently completed prototype atlas of Indigenous Perspectives and Knowledge.”

Cartoblography: Experiments in Using and Organising the Spatial Context of Micro-blogging

/ Matt Artz / 1 Comment

Transactions in GIS, Volume 14 Issue s1, Pages 5 – 23

Kenneth Field and James O’Brien

“Blogs, micro-blogs and online forums underpin a more interconnected world. People communicate ever more and are increasingly keen to explain and illustrate their lives; showing where they are and what they are doing. Desktop, online and mobile mapping landscapes have never been as rich or diverse yet this challenges cartography to adapt and remain relevant in the modern mapping world. We explore the spatial expression and potential value of micro-blogging and Twitter as a social networking tool. Examples of “twitter maps” are reviewed that leverage the Twitter API and online map services to locate some component of the “tweet”. Scope, function and design are illustrated through development of two proof-of-concept map mashups that support collaborative real-time mapping and the organisation and display of information for mass user events. Through the experiments in using and organising data in this way we demonstrate the value of “cartoblography”– a framework for mapping the spatial context of micro-blogging.”

Using a Reverse Auction to Promote Household Level Stormwater Control

/ Matt Artz

Environmental Science & Policy, In Press, Corrected Proof, Available online 20 April 2010

Hale W. Thurston, Michael A. Taylor, William D. Shuster, Allison H. Roy, and Matthew A. Morrison

“Phase II of the US Environmental Protection Agency’s (USEPA) National Pollution Discharge Elimination System (NPDES) stormwater regulations requires communities smaller than 100 000 residents to meet new criteria for stormwater runoff reduction. In many cases these smaller communities have no established stormwater utility, and are investigating alternatives for complying with these new, sometimes expensive requirements. We note that it might be cost effective for some communities to encourage homeowners to control stormwater runoff at the parcel level instead of, or in conjunction with more traditional large, infrastructural best management practices (BMP). We go onto argue that in the absence of a strict regulatory cap, an auction is a cost-effective tool for implementing controls on stormwater runoff quantity at the parcel level. In this paper, we test the effectiveness of a procurement auction as the coordinating mechanism for encouraging installation of parcel-scale rain gardens and rain barrels within a small suburban watershed in the Midwest. The auction, which was conducted in spring 2007 and 2008, resulted in installation of 81 gardens and 165 barrels on 107 of the 350 eligible properties. Average cost per liter of runoff detention in both years was $0.36 for gardens and $0.59 for barrels. Interestingly, approximately 55% of the bids were for $0, suggesting that an educational campaign may result in substantial runoff mitigation if utilities paid for the installation of stormwater management practices. However, we found that an auction promoted more participation than education alone and at a cheaper per-unit control cost than a flat stormwater control payment plan. Overall, this study demonstrates that relatively minimal financial incentives can result in homeowners’ willingness-to-accept stormwater management practices on their property, thus opening an important avenue for retrofitting watersheds that are largely in private ownership.”