Hydrodynamical simulations of galaxy properties: Environmental effects

Using N-body+hydro simulations we study relations between the local environments of galaxies on 0.5 Mpc scale and properties of the luminous components of galaxies. Our numerical simulations include effects of star formation and supernova feedback in different cosmological scenarios: the standard Cold Dark Matter model, the Broken Scale Invariance model (BSI), and a model with cosmological constant (LCDM). In this paper, we concentrate on the effects of environment on colors and morphologies of galaxies, on the star formation rate and on the relation between the total luminosity of a galaxy and its circular velocity. We demonstrate a statistically significant theoretical relationship between morphology and environment. In particular, there is a strong tendency for high-mass galaxies and for elliptical galaxies to form in denser environments, in agreement with observations. We find that in models with denser environments (CDM scenario) ~ 13 % of the galactic halos can be identified as field ellipticals, according to their colors. In simulations with less clustering (BSI and LCDM), the fraction of ellipticals is considerably lower (~ 2-3 %). The strong sensitivity of morphological type to environment is rather remarkable because our results are applicable to ``field'' galaxies and small groups. If all galaxies in our simulations are included, we find a statistically significant dependence of the galaxy luminosity - circular velocity relation on dark matter overdensity within spheres of radius 0.5 Mpc, for the CDM simulations. But if we remove ``elliptical'' galaxies from our analysis to mimic the Tully-Fisher relation for spirals, then no dependence is found in any model.Comment: 44 pages, 21 figures (17 included). Submitted to New Astronomy. GIFF color plots and the complete paper in Postscript (including color figures) can be found at http://astrosg.ft.uam.es/~gustavo/newas

Large Scale Morphological Segregation in Optically Selected Galaxy Redshift Catalogs

We present the results of an exhaustive analysis of the morphological segregation of galaxies in the CfA and SSRS catalogs through the scaling formalism. Morphological segregation between ellipticals and spirals has been detected at scales up to 15-20 h$^{-1}$ Mpc in the CfA catalog, and up to 20-30 h$^{-1}$ Mpc in the SSRS catalog. Moreover, it is present not only in the densest areas of the galaxy distribution, but also in zones of moderate density.Comment: 9 pages, (1 figure included), uuencode compressed Postscript, (accepted for publication in ApJ Letters), FTUAM-93-2

The structure of the ICM from High Resolution SPH simulations

We present results from a set of high (512^3 effective resolution), and ultra-high (1024^3) SPH adiabatic cosmological simulations of cluster formation aimed at studying the internal structure of the intracluster medium (ICM). We derive a self-consistent analytical model of the structure of the intracluster medium (ICM). We discuss the radial structure and scaling relations expected from purely gravitational collapse, and show that the choice of a particular halo model can have important consequences on the interpretation of observational data. The validity of the approximations of hydrostatic equilibrium and a polytropic equation of state are checked against results of our simulations. The properties of the ICM are fully specified when a 'universal' profile is assumed for either the dark or the baryonic component. We also show the first results from an unprecedented large-scale simulation of 500 Mpc/h and 2 times 512^3 gas and dark matter particles. This experiment will make possible a detailed study of the large-scale distribution of clusters as a function of their X-ray properties.Comment: 5 pages, 3 figures, to appear in the Proceedings of IAU Colloquium 195: "Outskirts of Galaxy Clusters: intense life in the suburbs", Torino Italy, March 200

Economic valuation of landscape in marinas: Application to a marina in Spanish Southern Mediterranean coast (Granada, Spain)

[EN] Assigning a monetary value to a landscape improves its importance. It helps to realize the magnitude of the benefits that can be obtained and represents the basis for applying protection and improvement policies. As a case study, we considered Marina del Este, located on the Spanish Southern Mediterranean coast, characterized by the presence of protected natural areas of great value and a rugged coastline beautiful to sailors. This study applies the analytic multicriteria valuation method (AMUVAN) to estimate the landscape¿s economic contribution. This method combines the analytic hierarchy process and discounted cash flow analysis. A total of 16 participants were considered, all with knowledge about the marina, which included areas of the marina management, management organizations with competencies in the marina environment, commercial operation, and university professors. They weighted the importance of landscape concerning the rest of the marina activities, use versus non-use values, and the components of the total economic value (TEV) of the landscape within marinas as a natural asset. Results expressed that the landscape may reach a value of around 16.3 million euros. It represents more than 3000% of the value of the marina¿s profit and loss account. A detailed analysis of the components of the TEV makes it possible to propose strategies to improve the economic value of the landscape.This research was funded by Ministerio de Ciencia e Innovación grant number PID2020-117056RB-100Martín, R.; Yepes, V. (2022). Economic valuation of landscape in marinas: Application to a marina in Spanish Southern Mediterranean coast (Granada, Spain). Land. 11(9):1-19. https://doi.org/10.3390/land1109140011911

The concept of landscape within marinas: Basis for consideration in the management

[EN] The landscape is a complex concept that deals with the relationship between people and their environment. The concept therefore encompasses many perspectives, and each area of knowledge approaches it di¿erently. Ports are unique elements within the landscape, with great attractiveness since ancient times, and its position on the coastline represents a superb base to observe their surroundings. Moreover, marinas are ports that specialize in pleasure crafts with a great potential for leisure. In this sense, this study introduces the landscape in the marinas ¿grounding its particularities of function and scale with respect to other port facilities¿ through a three-part Delphi survey that was conducted on a sample made up of an expert panel (n=23) in landscape and marinas from academia, consulting and management practice from Spain. Based on the concept of landscape, and after the analysis of existing literature and documents, the current research examines expert opinion on the various elements that embrace the landscape in marinas. Through a combination of open-ended responses, and Likerttype questions, the experts¿ panel attempts to identify the elements that should be considered in each of the approaching stages, and its respective rates. This set of criteria constitutes a starting point for a better understanding of the landscape in these types of maritime facilities. Also, it provides the basis to properly incorporate the landscape into the planning and management of marinas.Martín, R.; Yepes, V. (2019). The concept of landscape within marinas: Basis for consideration in the management. Ocean & Coastal Management. 179:1-14. https://doi.org/10.1016/j.ocecoaman.2019.104815S11417

Optimization of touristic distribution netwoorks using genetic algorithms

The eight basic elements to design genetic algorithms (GA) are described and applied to solve a low demand distribution problem of passengers for a hub airport in Alicante and 30 touristic destinations in Northern Africa and Western Europe. The flexibility of GA and the possibility of creating mutually beneficial feed-back processes with human intelligence to solve complex problems as well as the difficulties in detecting erroneous codes embedded in the software are described. A new three-parent edge mapped recombination operator is used to solve the capacitated vehicle routing problem required for estimating associated costs with touristic distribution networks of low demand. GA proved to be very flexible especially in changing business environments and to solve decision-making problems involving ambiguous and sometimes contradictory constraints.Peer Reviewe