Web-GIS tool for the management of rural land markets     

Juan Porta  Jorge Parapar  Paula García  Gracia Fernández  Juan Touriño  Ramón Doallo  Francisco Ónega  Inés Santé  Pablo Díaz  David Miranda  Rafael Crecente 《Earth Science Informatics》2013,6(4):209-226

Land abandonment and stagnation of rural markets in the last few years have become one of the main concerns of rural administrations. The use of Web and GIS (Geographic Information System) technologies can help to mitigate the effects of these problems. This paper pro-poses a novel Web-GIS tool with spatial capabilities for the dynamization of rural land markets by encouraging the transfer of land from owners to farmers through the leasing of plots. The system, based on open source software, offers information about the properties, their environment and their owners. It uses standards for handling the geographic information and for communicating with external data sources. This system was used as the basis for the development of SITEGAL, the tool for the management of the Land Bank of Galicia (www.bantegal.com/sitegal). SITEGAL has been operational since 2007 obtaining benefits for both administration and users (farmers and land owners), and promoting the e-Government.  相似文献   

Study of a rockfall in a limy conglomerate canyon (Covarrubias, Burgos, N. Spain)     

Leandro R. Alejano  Silverio García-Cortés  Fernando García-Bastante  Roberto Martínez-Alegría 《Environmental Earth Sciences》2013,70(6):2703-2717

In this paper, a rockfall of some tenths of cubic metres of rock, occurred in a conglomerate canyon in the northern Castilian plateau (N-Central Spain), is described in detail. This includes the basic data (geology, mapping, meteorological data and rock involved), the mechanical mechanism of the instability, the propagation and reach of the fallen rock boulders and the final location of the pieces. The study is based on detailed geological, aerial photography and geotechnical studies and advance topographical measurements. Geological engineering techniques are used to analyze the instability initiation and rockfall propagation. This study contributes to a better understanding of the geological processes leading to the occurrence of calcareous canyons and cliffs in the drainage network of the upper Castilian plateau. It is also helpful to improve our knowledge on natural rockfall phenomena for risk engineering purposes aiming to quantify, control and mitigate associated hazards.  相似文献   

Effect of the addition of granitic powder to an acidic soil from Galicia (NW Spain) in comparison with lime   总被引：1，自引：1，他引：0  

Benita?Silva  Remigio?ParadeloEmail author  Nuria?Vázquez  Eduardo?García-Rodeja  María?Teresa?Barral 《Environmental Earth Sciences》2013,69(2):429-441

The impact of diffuse pollution, agricultural land use and climate change on the long-term response of subsurface–surface water quality is not well understood, but is a prerequisite for evaluation of water management options. The goal of this study is to model geochemical evolution of water chemistry from the infiltration through soil into the unsaturated zone, transport through bedrocks and granular aquifers to a river in order to identify zones of steep concentration gradients and high dynamics under transient flow conditions. A numerical model was constructed comprising a 2-D 1,500 m × 150 m vertical cross-section of typical sedimentary rock formations, a glacio-fluvial quaternary gravel aquifer in the valley and soil layers. The model coupled saturated/un-saturated flow and reactive transport under steady state and transient conditions. Geochemical interactions, include intra-aqueous kinetic reactions of oxygen with dissolved organic matter, as well as kinetics of carbonate dissolution/precipitation. This model section was chosen to provide insight in to the principal processes and time scales affecting water chemistry along different flow paths. The numerical simulator MIN3P was used, a finite volume program for variably saturated subsurface flow and multi-component reactive transport. The results show that subsurface water residence times range from approximately 2 to 2,000 years. Different zones are to be expected with respect to the development of mineral equilibria; namely, purely atmospherically influenced, as well as open and closed system carbonate dissolution. Short-term responses to daily averaged changes in precipitation, however, are only visible to some extent in the shallower and near-river parts of flow system and solute loads. This can most likely be explained by directional changes in flow paths, indicating that equilibrium geochemical condition predominate at the hillslope scale, i.e. water quality depends on transport pathways rather than on kinetic effects. The extent of reducing conditions is controlled by the presence of organic-rich layers (i.e. peat deposits), the dissolution kinetics of aquifer organic matter and the subsequent mixing with oxygenated water by hydrodynamic dispersion.  相似文献   

Evaluation of sampling devices for the determination of polycyclic aromatic hydrocarbons in surface microlayer coastal waters     

Guitart C  García-Flor N  Dachs J  Bayona JM  Albaigés J 《Marine pollution bulletin》2004,48(9-10):961-968

The sea surface microlayer (SML) may play an important role on the transport and fate of persistent organic pollutants in the marine environment. In order to evaluate the appropriateness of a number of sampling devices for the analysis of 14 parent polycyclic aromatic hydrocarbons (3-5 aromatic rings), marine SML waters were sampled using a glass plate, a rotating drum/roller, a metal screen and a surface slick sampler. The underlying waters were also sampled for the determination of the corresponding enrichment factors (EF = [C](microlayer)/[C](underlying water)). The EFs were phase dependent, ranging from 1 to 3 for the dissolved phase and between 4 and 7 for the particulate phase. In order to better assess the performance of the different sampling methods, in terms of phase partitioning, the truly dissolved and colloidal phases were also estimated. Generally, no significant differences were found for the enrichment factors provided by the different methods, due to the observed large variability in concentrations that can be attributed to small-scale coastal processes. However, the metal screen is recommended as the most efficient sampling method for the study of PAHs taking into account the amount of water collected versus time.  相似文献   

Towards an operational system for oil-spill forecast over Spanish waters: initial developments and implementation test     

Sotillo MG  Fanjul EA  Castanedo S  Abascal AJ  Menendez J  Emelianov M  Olivella R  García-Ladona E  Ruiz-Villarreal M  Conde J  Gómez M  Conde P  Gutierrez AD  Medina R 《Marine pollution bulletin》2008,56(4):686-703

The ESEOO Project, launched after the Prestige crisis, has boosted operational oceanography capacities in Spain, creating new operational oceanographic services and increasing synergies between these new operational tools and already existing systems. In consequence, the present preparedness to face an oil-spill crisis is enhanced, significantly improving the operational response regarding ocean, meteorological and oil-spill monitoring and forecasting. A key aspect of this progress has been the agreement between the scientific community and the Spanish Search and Rescue Institution (SASEMAR), significantly favoured within the ESEOO framework. Important achievements of this collaboration are: (1) the design of protocols that at the crisis time provide operational state-of-the-art information, derived from both forecasting and observing systems; (2) the establishment, in case of oil-spill crisis, of a new specialized unit, named USyP, to monitor and forecast the marine oceanographic situation, providing the required met-ocean and oil-spill information for the crisis managers. The oil-spill crisis scenario simulated during the international search and rescue Exercise "Gijón-2006", organized by SASEMAR, represented an excellent opportunity to test the capabilities and the effectiveness of this USyP unit, as well as the protocols established to analyze and transfer information. The results presented in this work illustrate the effectiveness of the operational approach, and constitute an encouraging and improved base to face oil-spill crisis.  相似文献   

Accumulation of paralytic shellfish toxins in digestive gland of Octopus vulgaris during bloom events including the dinoflagellate Gymnodinium catenatum     

Pedro Reis Costa  Maria Joo Botelho  Susana Margarida Rodrigues 《Marine pollution bulletin》2009,58(11):1747-1750

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Macroinvertebrate patterns along environmental gradients and hydrological connectivity within a regulated river-floodplain     

Belinda Gallardo  Mercedes García  Álvaro Cabezas  Eduardo González  María González  Cecilia Ciancarelli  Francisco A. Comín 《Aquatic Sciences - Research Across Boundaries》2008,70(3):248-258

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A field study of coastal dynamics on a muddy coast offshore of Cassino beach,Brazil     

K. Todd Holland  Susana B. Vinzon  Lauro J. Calliari 《Continental Shelf Research》2009

Mud deposits near sandy beaches, found throughout the world, are of scientific and societal interest as they form important natural sea defenses by efficiently damping storm waves. A multi-national field experiment to study these phenomena was performed offshore Cassino beach in southern Brazil starting in 2004. This experiment aimed to investigate the formation of an offshore mud deposit, to characterize wave attenuation over potentially mobile muddy bottoms, and to evaluate the performance of models for wave transformation over heterogeneous beds through the measurement of water waves, near-bottom currents, bathymetry, and changes in bottom sediment characteristics. The main instrumentation was a set of wave sensors deployed in a transect from the shoreline across sandy and muddy deposits offshore to a depth of 25 m. Additional sensors, including current meters and optical backscatter sensors, were concentrated at stations in the middle of the mud deposit and in the surf zone to document aspects of the wave boundary layer and lutocline dynamics. This fieldwork also involved the geological and geotechnical characterization of the mud deposit using seismic equipment, echo-sounders, cores, surficial sampling and an in-situ density meter. These sediment samples were subsequently analyzed for density, grain size distribution, mineralogy, rheology and sedimentary structures. In addition, video and radar monitoring equipment were installed to measure the long-term aspects of surf zone damping by fluid mud and any associated morphodynamic responses. This paper provides a summary of environmental conditions monitored during the experiment and describes the major findings of the various investigations. Although data collection was more difficult than anticipated and dramatic wave attenuation involving the onshore transport of fluid mud into the surf zone region was not observed during the instrumented interval, the new methodologies developed and comprehensive observations obtained during this effort are being used to improve our understanding of shoaling wave dynamics and sediment transport in the coastal zone in regions with significant cohesive sediment deposits.  相似文献   

CO2-rich thermomineral groundwater in the Betic Cordilleras, southeastern Spain: Genesis and tectonic implications     

J. C. Cerón  M. Martín-Vallejo  L. García-Rossell 《Hydrogeology Journal》2000,8(2):209-217

The CO₂-rich thermal groundwater in the Betic Cordilleras in Spain has been studied with regard to the geological and hydrogeological setting, physical and chemical characteristics, and ¹³C-isotope content. The study area is about 60 km northeast of Almería city, in southeastern Spain. The thermomineral waters are plentiful and are related to regional geothermal anomalies. Temperatures of 20 −41°C, high bicarbonate concentrations (183–1824 mg/L), and high amounts of PCO₂ (<1.1 bar) characterize the groundwater. CO₂ spatial variations are related to proximity to the Carboneras, Palomares, and Guadalentín fault systems, which may be the surface representation of the zone of crustal thinning and magmatism. δ ¹³C values probably indicate a deep source for the CO₂, either the mantle or perhaps carbonate rocks in the metamorphic substratum. The high amount of CO₂ in the groundwater causes problems in wells and severely restricts water usage. The hydrothermal features of this area are probably related to neotectonic activity. Received, September 1998/Revised, June 1999, September 1999/Accepted, December 1999  相似文献   

The Evolution of HII Regions     

J. Franco  S.E. Kurtz  G. GarcÍa-Segura  P. Hofner 《Astrophysics and Space Science》2000,272(1-3):169-179

Here we review some recent results on the observed properties of UCH IIregions, and on the new class of Super-ultra-compact H II regions, and describe the theoretical scheme for H II region expansion, from star-forming cloud cores to the more diffuse external medium. High-pressure cores can stop the expansion on relatively short time scales, of the order of 3× 10⁴ yr, and the resulting pressure equilibrium UCH II regions have small sizes and large ion densities. If the ionization front enters into the decreasing density gradient of the cloud core, the expansion is accelerated and the H II region“pops” out of the core and becomes a “blister”-like region. The properties of the outflows depend on the cloud density structure, and a variety of different shocks can be formed. Density inhomogeneities inside photoionized regions are smoothed out on short time scales, but new clumps are continuously created at the cool shell generated by the shock front. Instabilities in both the ionization and shock fronts cause the fragmentation of the shell, maintaining the presence of clumps during the whole evolution. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献