Towards a spatial data infrastructure for technological disasters: an approach for the road transportation of hazardous materials

Spatial data have been used for the environmental monitoring of the consequences of accidents that involve the transportation of hazardous chemical products. This spatial data infrastructure (SDI), which was created for the sharing and use of spatial data, is limited by the absence of policies to support its establishment. The main objective of this study was to explore the use of social network analysis (SNA) as a tool to identify spatial data sharing between organizations involved in the management of accidents related to road transport of hazardous materials (RTHM). In addition, to discuss the existing policies and institutional agreements, and to initiate a conceptual SDI framework for RTHM sector. In this context, the institutions that are involved with RTHM were identified and information concerning their interest in the use and sharing of spatial data via a SDI was collected through interviews and consolidated. The interviews were at 39 institutions with representative employees. The interview data were tabulated and entered into the UCINET software (2000 version) to calculate metrics of centrality. From the SNA, the flow of data among the participating institutions was identified through the visual representation of the spatial data sharing and use networks. Subsequently, the existing institutional agreements for spatial data sharing were analyzed and discussed. The compiled results enabled the proposal of a conceptual SDI framework to support the management of disasters involving RTHM, based on the application of SNA theory, and the development of a methodology that supports the analysis of interactions among the various actors of an SDI. The purpose is to facilitate the formulation of policies for the sharing of spatial data for decision-making and preventive disaster management. The results indicate that the 39 institutions share spatial data, but this sharing is not always predetermined by formal agreements. Furthermore, there is a strong demand, by the institutions involved in the management of RTHM accidents, regarding legal mechanisms governing the sharing of data for the purpose of producing maps that help to describe actions of preparedness, prevention, management and immediate relief involving RTHM incidents. Finally, it was possible to propose a conceptual framework with data that is considered essential for creating an SDI for RTHM.     

Photosynthesis and Growth of Temperate and Sub-Tropical Estuarine Phytoplankton in a Scenario of Nutrient Enrichment under Solar Ultraviolet Radiation Exposure

We compared the responses of two estuarine phytoplankton communities, one from a temperate (Chubut River estuary (CH), Argentina) and one from a sub-tropical site (Babitonga Bay (BB), Brazil), in a scenario of nutrient enrichment under solar ultraviolet radiation (UVR) exposure. Seawater samples were exposed in microcosms to two nutrients, ambient vs. enriched, and two radiation conditions, with and without UVR, and exposed to solar radiation for 4 days. We evaluated the short- (PSII photochemistry, during 90 min light and 90 min dark cycles, before and after the , whereas in BB, nutrient effects prevailed. Such differences were related to the previous light history of the cells and to the ambient nutrient status. After acclimation, an overall improvement of the photosynthetic performance was observed at both sites, either by reducing the relative inhibition or by increasing the recovery of the effective photochemical quantum yield. Interactive effects of UVR and nutrients on growth at CH were antagonistic, while at BB, no differences were observed between the interactive and the sum of effects. Part of the differences in the mid-term observed responses can be attributed to taxonomic changes, with the CH community dominated by diatoms throughout the experiment, but with a shift from a diatom to a flagellate-dominated community in BB. Temperature differences between both sites might have favored higher growth rates and flagellates dominance in BB under the nutrient enriched conditions.     

Non-destructive xrf characterization of basaltic artifacts from Truckee,California

We have developed a new approach to the problem of the chemical fingerprinting of artifacts manufactured from volcanic rocks of basaltic and andesitic composition. The method is an adaptation of standard energy-dispersive X-ray fluorescence spectrometry and is based on the observation that for irregularly-shaped rock fragments, the ratios of the intensities of the characteristic X-rays of certain trace elements are proportional to the ratios of the concentrations of those elements. This observation has allowed us to obtain geochemical data about the artifacts in a way that is rapid, inexpensive, and nondestructive, making it particularly suited to archaeological applications. We have used our approach to compare a suite of artifacts from an archaeological site in Martis Valley, near Truckee, California, with a group of lava flows from the surrounding area. Using a numerical measure of the geochemical difference between samples, we have been able to group the artifacts on the basis of their geochemistry, to determine which artifacts were manufactured from material found in Martis Valley and, in at least one case, to identify the lava flow that was the actual source of the lithic material for several of the artifacts.