Diagnostic Techniques Applied in Geostatistics for Agricultural Data Analysis

Rev. Bras. Ciênc. Solo vol.33 no.6 Viçosa Nov./Dec. 2009

Joelmir André Borssoi; Miguel Angel Uribe-Opazo, and Manuel Galea Rojas

“The structural modeling of spatial dependence, using a geostatistical approach, is an indispensable tool to determine parameters that define this structure, applied on interpolation of values at unsampled points by kriging techniques. However, the estimation of parameters can be greatly affected by the presence of atypical observations in sampled data. The purpose of this study was to use diagnostic techniques in Gaussian spatial linear models in geostatistics to evaluate the sensitivity of maximum likelihood and restrict maximum likelihood estimators to small perturbations in these data. For this purpose, studies with simulated and experimental data were conducted. Results with simulated data showed that the diagnostic techniques were efficient to identify the perturbation in data. The results with real data indicated that atypical values among the sampled data may have a strong influence on thematic maps, thus changing the spatial dependence structure. The application of diagnostic techniques should be part of any geostatistical analysis, to ensure a better quality of the information from thematic maps.”

Spatial Analysis Helps Identify New York City Locations with High Incidence of Pedestrian Fatalities and Severe Injury Crashes

“Since the Fall of 2008, the Rudin Center researcher Dr. Hyeon-Shic Shin, in collaboration with researchers from Baruch College, State University of New York-Buffalo, Purdue University, and Rensselaer Polytechnic University, has been conducting a pedestrian safety study sponsored by the New York City Department of Transportation (NYCDOT). The study objectives are to identify priority locations for pedestrian safety treatments, priority street and intersections types, neighborhoods and populations, and to suggest planning and policy recommendations on pedestrian safety countermeasures.

“Focusing on the five boroughs of New York City, this study uses pedestrian fatal and severe injury crashes between 2002 and 2006. It investigates causal relationships between crashes and potential contributing factors such as socioeconomic characteristics, land use, street geometry, and many others. Using Geographic Information System’s spatial analysis functions (e.g., Moran’s I, Getis-Ord Gi, Kernel Density, and Cluster Analysis), 29 high crash locations throughout the City have been identified. Further analyses using advanced statistical models identified the potential contributing factors of pedestrian-vehicle crashes. Based on findings, planning and policy suggestions have also been provided to NYCDOT. The draft final report is currently in the review and revision stage. Upon approval, the findings from this study will be available as part of an upcoming NYCDOT report.”

[Source: New York Transportation Journal]

Less of Our Light for More Star Light: Join the 5th Worldwide Globe at Night 2010 Campaign, 3-16 March 2010!

What: The Globe at Night Campaign

When: 8pm to 10pm local time, 3-16 March 2010

Where: Everywhere

Who: You! (Everyone!)

How: See http://www.globeatnight.org

Why:

With half of the world’s population now living in cities, many urban dwellers have never experienced the wonderment of pristinely dark skies and maybe never will. This loss, caused by light pollution, is a concern on many fronts: safety, energy conservation, cost, health and effects on wildlife, as well as our ability to view the stars. Even though light pollution is a serious and growing global concern, it is one of the easiest environmental problems you can address on local levels.

Globe at Night is an annual 2-week campaign in March that helps to address the light pollution issue locally as well as globally. This year the campaign is March 3-16, 2010. You are invited along with everyone all over the world to record the brightness of your night sky by matching its appearance toward the constellation Orion with star maps of progressively fainter stars found at http://www.globeatnight.org/observe_magnitude.html. You then submit your measurements on-line at http://www.globeatnight.org/report.html

with your date, time and location. A few weeks later, organizers release a map of light-pollution levels worldwide. Over the last four 2-week Globe at Night campaigns, volunteers from over 100 nations have contributed 35,000 measurements.

To learn the five easy steps to participate in the Globe at Night program, see the Globe at Night website at http://www.globeatnight.org.   You can listen to our 10-minute audio podcast on light pollution and Globe at Night at http://365daysofastronomy.org/2010/02/03/february-3rd-the-globe-at-night-campaign-our-light-or-starlight/

For activities that have children explore what light pollution is, what its effects are on wildlife and how to prepare for participating in the Globe at Night campaign, see the new activities at http://www.darkskiesawareness.org/DarkSkiesRangers.

Monitoring our environment will allow us as citizen-scientists to identify and preserve the dark sky oases in cities and locate areas where light pollution is increasing. All it takes is a few minutes during the March 2010 campaign to measure sky brightness and contribute those observations on-line. Help us exceed the 15,000 observations contributed last year. Your measurements will make a world of difference.

Post Doc Opprotunity: Remote Sensing in Forest Ecosystems, Istituto Agrario San Michele all’Adige

“Primary responsibility is to analyse high resolution hyperspectral and Lidar data of forest ecosystems located in the complex alpine region. The scientific activity aims to understand the sensitivity of carbon and nitrogen cycles to climate and land use changes using spatially processbased models, remote sensing and other spatial techniques on a range of different spatial scales. Models development and analysis, parameter estimation, sensitivity analysis and simulations of different scenarios are other objectives.

“Experience with Lidar and hyperspectral data analysis in complex areas and previous work with large database are required. Candidates will be preferably familiar with a programming language such as C, FORTRAN, or MATLAB and have prior experience or training in forest ecosystems classification and analysis of Lidar data for forest structure and biophysical parameter estimation.

“The candidate should also have experience in planning and implementing scientific projects, including writing research proposals, and have a good written scientific record.”

Coastal-Change and Glaciological Map of the Palmer Land Area, Antarctica: 1947 to 2009

By Jane G. Ferrigno, Alison J. Cook, Amy M. Mathie, Richard S. Williams, Jr., Charles Swithinbank, Kevin M. Foley, Adrian J. Fox, Janet W. Thomson, and Jörn Sievers

“Reduction in the area and volume of the two polar ice sheets is intricately linked to changes in global climate, and the resulting rise in sea level could severely impact the densely populated coastal regions on Earth. Antarctica is Earth’s largest reservoir of glacial ice. Melting of the West Antarctic part alone of the Antarctic ice sheet would cause a sea-level rise of approximately 6 meters (m), and the potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). The mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is highly complex, responding differently to different climatic and other conditions in each region (Vaughan, 2005). In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic ice sheet is probably becoming thinner overall; although it is known to be thickening in the west, it is thinning in the north. The mass balance of the East Antarctic ice sheet is thought by Davis and others (2005) to be positive on the basis of the change in satellite-altimetry measurements made between 1992 and 2003.

“Measurement of changes in area and mass balance of the Antarctic ice sheet was given a very high priority in recommendations by the Polar Research Board of the National Research Council (1986), in subsequent recommendations by the Scientific Committee on Antarctic Research (SCAR) (1989, 1993), and by the National Science Foundation’s (1990) Division of Polar Programs. On the basis of these recommendations, the U.S. Geological Survey (USGS) decided that the archive of early 1970s Landsat 1, 2, and 3 Multispectral Scanner (MSS) images of Antarctica and the subsequent repeat coverage made possible with Landsat and other satellite images provided an excellent means of documenting changes in the cryospheric coastline of Antarctica (Ferrigno and Gould, 1987). The availability of this information provided the impetus for carrying out a comprehensive analysis of the glaciological features of the coastal regions and changes in ice fronts of Antarctica (Swithinbank, 1988; Williams and Ferrigno, 1988). The project was later modified to include Landsat 4 and 5 MSS and Thematic Mapper (TM) images (and in some areas Landsat 7 Enhanced Thematic Mapper Plus (ETM+) images), RADARSAT images, aerial photography, and other data where available, to compare changes that occurred during a 20- to 25- or 30-year time interval (or longer where data were available, as in the Antarctic Peninsula). The results of the analysis are being used to produce a digital database and a series of USGS Geologic Investigations Series Maps (I-2600) (Williams and others, 1995; Swithinbank and others, 2003a,b, 2004; Ferrigno and others, 2002, 2005, 2006, 2007, 2008, and in press; and Williams and Ferrigno, 2005) (available online at http://www.glaciers.er.usgs.gov).”

Climate Warming Effects on the Olea Europaea–Bactrocera Oleae System in Mediterranean Islands: Sardinia as an Example

Global Change Biology, April 2009, 15:2874–2884

Luigi Ponti , Q. Antonio Cossu, and Andrew Paul Gutierrez

“Global warming will affect all species but in largely unknown ways, with certain regions such as the Mediterranean Basin and its major islands including Sardinia being particularly vulnerable to desertification. Olive (Olea europaea) is of eco-social importance in the Mediterranean where it was domesticated. This drought-resistant crop and its major pest, the olive fly (Bactrocera oleae), have tight biological links that make them a suitable model system for climate change studies in the Mediterranean. Here a physiologically based weather-driven demographic model of olive and olive fly is used to analyze in detail this plant–pest system in Sardinia under observed weather (10 years of daily data from 48 locations), three climate warming scenarios (increases of 1, 2 and 3 °C in average daily temperature), and a 105-year climate model scenario for the Alghero location (e.g. 1951–2055). GRASS GIS is used to map model predictions of olive bloom dates and yield, total season-long olive fly pupae, and percent fruit attacked by the fly. Island wide simulation data are summarized using multivariate regression. Model calibration with field bloom date data were performed to increase simulation accuracy of olive flowering predictions under climate change. As climate warms, the range of olive is predicted to expand to higher altitudes and consolidate elsewhere, especially in coastal areas. The range of olive fly will extend into previously unfavorable cold areas, but will contract in warm inland lowlands where temperatures approach its upper thermal limits. Consequently, many areas of current high risk are predicted to have decreased risk of fly damage with climate warming. Simulation using a 105-year climate model scenario for Alghero, Sardinia predicts changes in the olive–olive fly system expected to occur if climate continued to warm at the low rate observed during in the past half century.”

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