Stanford Geospatial Center

The Osa & Golfito Initiative, “INOGO”, is an international collaborative effort to develop a strategy for sustainable human development and environmental stewardship in the Osa and Golfito Cantons of Costa Rica. The effort’s core is a collaboration between people and institutions in the US and Costa Rica, facilitated by the Stanford Woods Institute for the Environment at Stanford University. The Initiative members have an extensive range of knowledge — from education to marine ecosystems — permitting a holistic analysis of the issues in the region. Faculty members from Stanford include William Durham (Anthropology), Rodolfo Dirzo (Biology), Larry Crowder (Center for Ocean Solutions), Lynne Gaffikin (School of Medicine), and Martin Carnoy (Education and Economics). For more information please see the INOGO project website or contact Emily Arnold (ebarnold@stanford.edu). For questions specific to our use of ArcGIS Online please contact Eben Broadbent (eben@amazonico.org).

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Landscape evolution is often studied by using elemental and isotopic concentrations in stream waters and their deposits as proxies for paleo-weathering and erosion rates. In this study, we test this relationship in a modern drainage system by examining for statistically significant correlations between landscape properties of watersheds and their respective stream water solute concentrations for 14 sample sites in the Feather River drainage system of the Sierra Nevada, California.

Landscape properties examined include watershed area, slope, curvature, and aspect. Modeling results show that watershed properties are unable to explain stream water elemental concentrations, indicating that other factors (such as fluid residence time in the soil) may need to be taken into consideration. Further analysis shows that Fe concentrations have a significant positive correlation with Al concentrations, which may represent the formation of kaolinite in certain areas of the stream profile. This indicates that the model also needs to better account for physical and chemical processes, such as clay formation, that are likely impacting solute concentrations in the stream water.

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Precise relative gravity measurements conducted in Long Valley (California) in 1982 and 1998 reveal a decrease in gravity of as much as -107 ± 6 microgals (1 microgal = 10–8 meters per square second) centered on the uplifting resurgent dome. A positive residual gravity change of up to 64 ± 15 microgals was found after correcting for the effects of uplift and water table fluctuations. Assuming a point source of intrusion, the density of the intruding material is 2.7 × 103 to 4.1 × 103 kilograms per cubic meter at 95 percent confidence. The gravity results require intrusion of silicate magma and exclude in situ thermal expansion or pressurization of the hydrothermal system as the cause of uplift and seismicity

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The Martu aboriginal group is known to use fire as a hunting tool and has had a strong influence on ecological fire regimes in the Western Australian desert. Michelle, Caleb and Rachel used historical aerial photographs from two sites in Martu tribal land to analyze differences in natural and anthropogenic fire regimes. One site contains several waterholes and the other site contains only a few. It has been hypothesized that water sources can be used as a proxy for human activity in severely water-limited ecosystems. GIS analysis demonstrates that there are significant differences in the spatial patterns of fires across the two test sites. However, landscapes within one hunting day’s distance of a waterhole were not significantly patchier than random points. Furthermore, the area of a fire was not well predicted by its distance to nearest waterhole. There is some evidence that distance to modern roads predicts fire size, but more sites need to be analyzed to determine whether either variable is an appropriate surrogate for human habitation.

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Ohio always plays a key role in deciding the outcome of presidential elections. Candidates are especially invested in Ohio, with its varying demographics (highly concentrated urban areas juxtaposed with rural farmlands) and substantial number of electoral votes that make it an important swing state. Dylan, Dylan and Hannah evaluated political participation in terms of campaign donations. In addition to looking at the sheer number of donations for a given area they also explored how the size of donations varied over different regions. In this project they looked at the relationship between the total number of donations in each Ohio zip code, the total monetary amount raised by those donations in the 2012 election, and those zip codes’ proximities to a) campaign field office locations, and b) institutions of higher learning.

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In response to the growing need for refugee camps as a result of the crisis in Syria, Jennifer and Sophia performed a site analysis for the already established 16 camps in Turkey in order to determine which ones may be less suitable than others and at higher risk than others, especially as winter approached in 2012. By examining six different factors, they hoped to determine which camps will need more support or resources and additionally which areas near the border may be most appropriate to set up additional camps. Thus the research questions they were most interested in were:

• Which factors make Syrian refugee camps more risky to live in than others in Turkey and how?
• Where is the most suitable location for new refugee camps to accommodate incoming refugees?
• How can we use this analysis to inform the Turkish government as to which camps should receive more funding, resources, and attention?

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Air pollution has serious public health implications causing between 22,000-52,000 premature deaths and countless cases of illness in the United States of America each year (Mokdad et al, 2004). The goal of this project was to estimate the spatial distribution and magnitude of health impacts from air pollution, specifically exposure to fine particulate matter and ozone, over one year in New York State (NYS). Mariana, Daniela, Megan and Marilu hope to provide the population of NYS with a resource to better understand the harmful effects of poor air quality and the motivation to address sources of air pollution.

Pollutant concentrations of ozone (O3) and fine particulate matter (PM2.5) measured by air quality monitors were interpolated over the area of New York using Empirical Bayesian Kriging and averaged over each census block in the state. Based on these interpolated concentrations of O3 and PM2.5, they calculated incidence of asthma, bronchitis, congestive heart failure in elderly, risk of death from cancer, hospital admissions due to pollution exposure, and premature death for each census block’s population. Using data primarily from 2010, they estimated 6,000 premature deaths are attributed to air pollution in NYS annually and thousands of cases of the other health indicators.

They also analyzed the distribution and magnitude of stationary point-source PM2.5 emissions from industrial-scale combustion facilities using a hot spot analysis and ordinary least squares regression. They found no statistically significant correlation between stationary point source emissions and air concentrations, likely due to the high level of uncertainty in our interpolated concentrations which does not capture local variability, as well as the lack of other important factors such as meteorological conditions. Finally, they investigated the correlation between pollution exposure and various demographic groups and at-risk populations, but found no statistically significant difference in exposure among any group. Maps showing air pollution concentrations, potential pollutant sources, populations at risk, and estimated health impacts were created to visualize the results.

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In countries with large rural populations, health care accessibility is largely dependent on transportation conditions. Riders for Health, a UK based NGO, aims to increase accessibility by providing fleet management services, such as training health workers to use vehicles responsibly in the face of the challenging Zambian landscape. To determine whether these services areeffective in improving accessibility to healthcare, this paper aims to analyze 1) if Riders for Health has increased service outreach efforts, and 2) if population, precipitation, and accessibility (combing terrain and distance factors) impacts the distribution of service points.

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In order to assess disparities in the accessibility of drinking water in Kenya, Jeff and Maeva created an index of drinking water accessibility based on the quantity of available water, the water supply type, the level of water treatment employed, and the temporal accessibility of water sources. They employed the Demographic and Health Survey (DHS) dataset to georeference data pertaining to water fetch-times, water treatment before drinking, and water supply type. They also employed an annual average of precipitation across Kenya, and assessed proximity to water sources using basemaps with water-body polygons, and hydrologic data on the distribution of groundwater reservoirs and annual yields. The four parameters (quality, type, treatment, and time) were converted to raster datasets, reclassified, then summed using the Raster Calculator to produce a final index of drinking water accessibility (DWAI). Based on their results, while most Kenyan populations have poor to moderate drinking water accessibility, the spatial variation in DWAI is not statistically correlated to variation in wealth, health, education, or distance from major urban centers.

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In this project, Mona and Magdalena worked with CALPIRG Energy Service Corps to identify areas in Santa Clara County most suitable for their residential energy outreach programs. Using layers of proximity to college campuses, block group energy ranking, and land use zoning, they calculated the average suitability ranking for the 861 Santa Clara County block groups and assigned each a ranking that represented the efficiency and effectiveness of CALPIRG's future outreach.

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A vital element of transitioning from fossil fuel based energy resources to renewable resources such as solar and wind is the creation of a new electricity transmission grid network that facilitates connection of renewable energy resources to areas of high demand, namely urban areas such as cities with populations over 100,000. The new transmission network must achieve four basic goals: (1) Ensure nationwide connectivity, (2) Facilitate renewable energy integration, (3) Subject the transmission grid to conventional constraints for siting transmission lines, and (4) Ensure a balanced approach that meets as many stakeholder needs as possible. Leon, Mei, Shuang and Randall aimed to make a simplified plan for creation of such a network, using script-based modeling that maximizes convertibility. The model enables flexibility in changing cost layers, connectivity standards and adding extra constraints. They developed two grid siting plans, the first designed to connect 212 urban areas with populations greater than 100,000 to renewable resources, and the second grid siting plan connecting populations greater than 300,000.

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Amy and Kendra conducted a site-suitability analysis for wind energy development in Salinas Valley in Monterey County, CA. The purpose of their project was to identify land parcels eligible for wind turbines, specify the location and number of turbines per parcel, rank the parcels for optimal suitability, and perform a visual analysis of the viewsheds of the proposed turbines. They used wind resource data from the National Renewable Energy Lab, U.S. Census data for urban areas and populated places, the 10m resolution NED DEM from the USGS, and data from anemometers in the Salinas Valley georeferenced using Google Earth Pro. By employing the fishnet, buffer, union, and observer point analysis tools, Amy and Kendra were able to create a summarizing site suitability surface. They conclude that there is significant wind energy potential in Salinas Valley, but that prior to turbine construction, there is need for additional electrical substations, and further research to determine which locations would be optimal for new substations.

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In 2009 the Brazilian Federal Government passed a new land law (Federal Law 11952/2009) for regularizing the tenure situation for land parcels up to 1500 square kilometers, many of them with deforested areas. Three years later, Congress passed a new forest code decreasing the mandatory size for recovering illegally deforested areas in private properties.

Brenda and Theo evaluated the actual impact of the implementation of these laws on deforestation and restoration at the municipal level in the state of Pará according to the following questions: i) what is the impact of the new forest code on restoration obligation in a selected number of municipalities in Para?; ii) what were the deforestation rates before and after 2009 on the properties that received land titles due to the 2009 land law?; iii) in the case of deforestation on those properties, what is the impact on restoration obligation of the 2012 forest code law?

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Fertilizer is widely used to increase crop yield by farmers in the United States, and one of the main elements used in fertilizer is nitrogen. Although nitrogen helps crop productivity, too much nitrogen can be harmful to humans. As fertilizer use increases, the possibility that it contaminates groundwater also increases and human exposure is more likely to occur. Through research and the use of ArcGIS we wanted to answer the following two questions. Where in the San Joaquin Valley is there a high vulnerability of nitrate contamination of groundwater? How does this relate to measured values of dissolved nitrate in groundwater? The answers to these questions can help educate farmers on their fertilizer use and illustrate where people should be concerned about nitrate-contaminated drinking water.

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Agricultural pesticides are a major source of pollution in California’s Central Valley. The goal of this project was to examine the relationship between pesticide usage and both public health and water quality. Our first analysis looked at the relationship between pesticide usage and population density of children under 15 to assess the extent of exposure of this vulnerable population. Our second analysis looked at the relationship between pesticide usage and water quality, using a risk index based on pesticide toxicity. We did not find significant spatial relationships in either case. In the first case, this indicates that populations of children under 15 do not live in areas with high pesticide usage. In the second case, this indicates that distance from pesticide application site is not a good predictor for water quality risk from pesticide pollution. Future studies would incorporate more relevant variables related to pesticide transport in the environment.

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In their project, Sarah, Christina, and Sasha set out to determine how commercial shipping affects the health of the marine ecosystem in the Gulf of Alaska and to what extent these impacts are concentrated around ports and marine protected areas. To do so, they analyzed marine ecological and shipping lane data from the National Center for Ecological Analysis and Synthesis (NCEAS), calculating the percentage of MPAs that intersect with shipping lanes and the spatial coincidence of highly impacted areas with MPAs and ports. The study concludes that areas around ports highly impacted in terms of concentrations of pollutants and invasive species, and that MPAs are minimally environmentally impacted despite high shipping traffic.

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Hawaii is an archipelago in one of the most geographically isolated regions of the world. In part for this reason, regional food security via reduced dependency on imported food has recently been suggested as a public policy goal of the region. The objective of Jesse, Laura, Matt and Zach in this project was to evaluate the potential for Hawaii to produce enough food to feed its current population, in addition to evaluating this potential on a regional basis, by census tract. They identified land suitable for agriculture on the islands using the following factors: slope (derived from elevation), soil class, mean annual precipitation, land occupied by protected areas, and land cover. They then calculated land available for agriculture by census tract. Using this land area, they estimated how many people could be supported, both on the islands overall as well as per census tract, using three different diets: an American diet, a vegan diet based on conventional agriculture (vegan conventional), and a vegan diet based on biointensive agriculture (vegan biointensive). They compared these estimates to current population levels by census tract, to evaluate the sustainability, or potential for food security, given current population levels.

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In this report, Casey, Judee, and Erin sought to identify the regions in the conterminous United States that will need to adjust their current management practices with respect to corn production by the year 2050 due to changing climate. In order to identify these regions, a suitability surface was created for determining the regions currently most suitable for growing corn based on indexed biophysical and climate factors. This surface was then recreated using projections of climate conditions in 2050, and the differences between suitability surfaces was calculated. By comparing the spatial distribution of marked differences in the suitability of regions of the conterminous U.S. for corn production to spatial patterns in the amount of corn currently produced in the U.S., regions that produce a significant amount of corn that will be negatively impacted by climate, as well as regions that produce little corn that will become more amenable to corn production given climate change were identified.

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Using ArcGIS software, Alex, Adelaide and Joanna examined food accessibility in the city of San Francisco, CA. Their study sought to determine the relationship between food accessibility and income level within the city. They employed datasets describing the location of grocers, farmers’ markets, and food banks in San Francisco, in addition to census income data. They employed Network Analyst and Spatial Statistics tools in to determine the areas of the city serviced by these food access points, as well as the correlation between income level and proximity to food access points. Results indicate that there is no significant difference in food access across San Francisco’s income levels.

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Christopher Perle compared the movements and habitats of two female salmon sharks. His analysis was based on data recovered from tags deployed by the Tagging of Pacific Pelagics program (TOPP). The raw positional data were transmitted to satellites, downloaded via ARGOS, and run through a Bayesian State Space Model to estimate one position and behavior mode per day. Time series from recovered archival tags were decoded and plotted by hour and day, showing depth (meters), temperature or light preferences using MATLAB scripts. Christopher incorporated 4D netCDF biological oceanography data using the Environmental Data Connector extension to ArcGIS. By comparing the migration patterns of the two sharks in three dimensions, oceanographers and marine ecologists can use analysis to enhance marine conservation.

Christopher’s poster received the third place prize of the 2009 BAAMA Educational Scholarship. He is a Phd candidate in Biological Sciences and is based at the Stanford Hopkins Marine Station.

Argentine ants are an invasive species worldwide and have invaded roughly a third of JRBP from disturbed areas near the Preserve’s perimeter. Since 1993, PhD students in Prof. Deborah Gordon’s lab, most recently Nicole Heller and Jessica Shors, have monitored the invasion every May and September by censusing survey points on a 100m grid throughout the accessible parts of the Preserve. The survey consists of recording all species of ants observed within a 20m radius of the survey points.

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The Jasper Ridge bird monitoring program consists of two separate but complementary surveys whose goal is to create a body of data that can be used to detect trends in many aspects of avian ecology, both within specific habitats and for JRBP as a whole. A hallmark of the program is the longterm commitment by a number of expert birders, who conceived the program and have provided consistency and a collective memory.

The transect survey was started over three decades ago and consists of six defined routes that are monitored monthly. These surveys involve teams of several people, all of whom detect, identify, and count individuals along a series of trails. Some transects involve split routes over part of the loop and are best surveyed by teams of four people.

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