Search results for "Nature"
showing 10 items of 1564 documents
Modeling Rain Isotopic Composition under Orographic Control: A Landscape Approach for Hydrogeological Applications
2021
Oxygen isotopic composition is useful for individuating recharge areas of groundwater bodies by the comparison with those of local rainfalls. While on a global scale general relationships, such as the isotopic vertical gradient or continentality effects, efficiently describe spatial variations of the isotopic signature, hydrogeological applications need spatial models that are more focused on the effects of local topographic structures and/or subsoil geology. This work presents a case study in northeastern Sicily (Italy) characterized by complex geological and orographic structures, in which isotopic composition of rainfalls is governed by orographic effects and the varying initial composit…
Trends in global research in deforestation. A bibliometric analysis
2018
The main aim of this study was to analyse topics of research, scientific production, collaboration among countries, and most cited papers on deforestation through a bibliometric and social network study of articles found in the Web of Science database. The most productive subject areas corresponded to Environmental Sciences, Ecology and Environmental Studies. The articles were published in 458 different journals. A total of 2051 research articles were obtained. The main challenges identified for deforestation include “land use change” “conservation” “climate change” “rain forest” and “reducing emissions from deforestation and degradation”. Social and economic topics are understudied. An imp…
Causas y consecuencias del crecimiento urbanístico en el litoral valenciano a través de la evolución de los usos del suelo. El caso de Oliva.
2019
Mediante la fotointerpretación de imágenes aéreas con la utilización de técnicas SIG y a través de un intenso trabajo bibliográfico y de campo, se realiza un análisis diacrónico (1956, 1991 y 2015) de la evolución de los usos del suelo en Oliva (València, España). A partir de este análisis multimetodológico se estudia la evolución de la situación urbanística y de las dinámicas territoriales en un municipio paradigmático para explicar la evolución urbanística del litoral valenciano en las últimas décadas. In this paper we have carried out a diachronic analysis about land uses evolution in Olive through a mixed method of research, based on photo-interpretation of aerial images (years 1956, 19…
A Participatory Agrobiodiversity Conservation Approach in the Oases: Community Actions for the Promotion of Sustainable Development in Fragile Areas
2021
Rural development policies today include significant directions towards ecological transition and sustainability. Biodiversity plays a fundamental role, especially in fragile environments. The North African oases, for example, are socio-ecological structures with delicate balances in terms of natural resources, where the activation of participatory conservation approaches appears today to be very useful, aiming at long-lasting results. This type of approach was applied in the oasis of El Hamma, in Tunisia. The socio-ecological analysis was carried out through semi-structured interviews with different stakeholders of the oasis. The results were used to activate focus groups and to identify, …
Understanding the Origins of Problem Geomagnetic Storms Associated with "Stealth" Coronal Mass Ejections.
2021
Geomagnetic storms are an important aspect of space weather and can result in significant impacts on space- and ground-based assets. The majority of strong storms are associated with the passage of interplanetary coronal mass ejections (ICMEs) in the near-Earth environment. In many cases, these ICMEs can be traced back unambiguously to a specific coronal mass ejection (CME) and solar activity on the frontside of the Sun. Hence, predicting the arrival of ICMEs at Earth from routine observations of CMEs and solar activity currently makes a major contribution to the forecasting of geomagnetic storms. However, it is clear that some ICMEs, which may also cause enhanced geomagnetic activity, cann…
Characterisation of the magmatic signature in gas emissions from Turrialba Volcano, Costa Rica
2014
The equilibrium composition of volcanic gases with their magma is often overprinted by interaction with a shallow hydrothermal system. Identifying the magmatic signature of volcanic gases is critical to relate their composition to properties of the magma (temperature, fO2, gas-melt segregation depth). We report measurements of the chemical composition and flux of the major gas species emitted from Turrialba Volcano during March 2013. Measurements were made of two vents in the summit region, one of which opened in 2010 and the other in 2012. We determined an average SO2 flux of 5.2 ± 1.9 kg s-1 using scanning ultraviolet spectroscopy, and molar proportions of H2O, CO2, SO2, HCl, CO and H2 ga…
Evolution of the neodymium isotopic signature of neritic seawater on a northwestern Pacific margin: new constrains on possible end-members for the co…
2013
11 pages; International audience; The Neodymium(Nd) isotope composition of fish remains has beenwidely used to track past changes in oceanic circulation. Although the number of published Nd isotope data for the Cretaceous has markedly increased in the last years, no consensus has been reached on the structure of the oceanic circulation and its evolution during the Late Cretaceous. Yet this period is characterised bymajor geodynamical and climatic changes andmarked by the disappearance of global oceanic anoxic events inwhich changes in oceanic circulation modesmay have played a significant role. In this study we present the first record of Nd isotopic composition of fish remains from contine…
Gravitational wave signature of proto-neutron star convection: I. MHD numerical simulations
2021
Gravitational waves provide a unique and powerful opportunity to constrain the dynamics in the interior of proto-neutron stars during core collapse supernovae. Convective motions play an important role in generating neutron stars magnetic fields, which could explain magnetar formation in the presence of fast rotation. We compute the gravitational wave emission from proto-neutron star convection and its associated dynamo, by post-processing three-dimensional MHD simulations of a model restricted to the convective zone in the anelastic approximation. We consider two different proto-neutron star structures representative of early times (with a convective layer) and late times (when the star is…
A New Network for the Advancement of Marine Biotechnology in Europe and Beyond
2020
Marine organisms produce a vast diversity of metabolites with biological activities useful for humans, e.g., cytotoxic, antioxidant, anti-microbial, insecticidal, herbicidal, anticancer, pro-osteogenic and pro-regenerative, analgesic, anti-inflammatory, anticoagulant, cholesterol-lowering, nutritional, photoprotective, horticultural or other beneficial properties. These metabolites could help satisfy the increasing demand for alternative sources of nutraceuticals, pharmaceuticals, cosmeceuticals, food, feed, and novel bio-based products. in addition, marine biomass itself can serve as the source material for the production of various bulk commodities (e.g., biofuels, bioplastics, biomateria…
From USSR to EU: 20 years of rural landscape changes in Vidzeme, Latvia
2012
Landscape changes have been observed throughout rural Europe over the past decades in relation to intensifying agriculture and land marginalisation. This is particularly true for Central and Eastern Europe as drastic political and socio-economic changes have taken place over the past century, as is the case for Latvia. Using a detailed time series of high-resolution remotely sensed images spanning from 1988 to 2007, the landscape structure (composition and configuration) in Vidzeme, central Latvia, is examined and compared between periods. Major recent events for the country, such as independence and entry into the European Union are covered. The effect on landscape structure of various soc…