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261.
The Portuguese National Ecological Reserve (NER) was created in 1983, with the aim of preserving, in certain areas, the biophysical structure necessary to maintain exploitation of natural resources and land use without jeopardizing their sustainability. For the first time, issues related to groundwater resources were addressed. Since then, this legal tool has been revised for a better integration of the new national and European legislation and new scientific and technical knowledge. In the latest NER, the concept of “strategic areas of protection and aquifer recharge (SAPAR)” was created, being now necessary to define which are the methodologies and criteria to be applied for its delimitation. This paper summarizes the strategic guidelines that were established from debates held in several meetings with land-use planners, water resources managers, specialists and other stakeholders concerning the development of harmonized definitions and criteria of NER. As a result of those contributions a report was elaborated where guidelines and criteria for the NER delimitation were defined at national level, in accordance with national legislation and other relevant sector plans. In this work, the articulation and integration of SAPAR-protected areas in Portuguese Water Act and the expected difficulties of its application at operative level are evaluated since the SAPAR are important for the control of urban sprawl and therefore to preserve groundwater resources and dependent ecosystems. A brief explanation about the Portuguese main hydrogeological features is given for a better understanding of the groundwater resources and dependent ecosystems. Finally, the key guidelines for a good NER delimitation are compiled. 相似文献
262.
Dale Dominey-Howes Paula Dunbar Jesse Varner Maria Papathoma-Köhle 《Natural Hazards》2010,53(1):43-61
The Cascadia margin is capable of generating large magnitude seismic-tsunami. We use a 1:500 year tsunami hazard flood layer
produced during a probabilistic tsunami hazard assessment as the input to a pilot study of the vulnerability of residential and commercial buildings in Seaside, OR, USA. We map building
exposure, apply the Papathoma Tsunami Vulnerability Assessment Model to calculate building vulnerability and estimate probable maximum loss (PML) associated with a 1:500 year tsunami flood. Almost US$0.5 billion worth of buildings would be inundated, 95% of single
story residential and 23% of commercial buildings would be destroyed with PML’s exceeding US$0.5 billion worth of buildings would be inundated, 95% of single
story residential and 23% of commercial buildings would be destroyed with PML’s exceeding US116 million. These figures only
represent a tiny fraction of the total values of exposed assets and loss that would be associated with a Cascadia tsunami
impacting the NW Pacific coast. Not withstanding the various issues associated with our approach, this study represents the
first time that PML’s have ever been calculated for a Cascadia type tsunami, and these results have serious implications for
tsunami disaster risk management in the region. This method has the potential to be rolled out across the United States and
elsewhere for estimating building vulnerability and loss to tsunami. 相似文献
263.
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. 相似文献