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1.
J Environ Manage ; 346: 118959, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37734215

RESUMO

Environmental crimes are a global issue due to the damage they cause to landscapes and ecosystems. This study focused on characterizing environmental crimes in the Canary Islands (Spain). Four categories of environmental crimes related to construction, mining and tilling, solid waste, and liquid waste) were defined and analysed. A total of 28 databases were generated, corresponding to each of the 7 major islands and each environmental crime typology. Each database was linked to information on land use and the socioeconomic and physical characteristics of the territory. For each database, firstly a descriptive statistical analysis was conducted, followed by the generation of a regularized Random Forest model with the aim of identifying characteristics that may be related to the location of environmental crimes. The results showed that, in most cases, proximity to residential accommodations, agricultural areas and industrial zones act as the main explanatory features of the distribution of environmental crimes. Furthermore, a marked pattern of concentration of environmental crimes in the coastal belt of the islands was observed, mainly associated with urban-tourist development since the 1960s and 1970s.


Assuntos
Efeitos Antropogênicos , Ecossistema , Humanos , Espanha , Crime , Ilhas
2.
Sci Total Environ ; 815: 152868, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34998756

RESUMO

Foredunes in arid coastal dune systems comprise nebkhas, which originate by interactions between vegetation and aeolian sedimentation. While continuous foredunes in temperate climates have been widely studied, knowledge of interactions between biotic and abiotic drivers in foredunes formed by nebkha is still scarce. With the aim of exploring variables affecting arid foredunes, a range of morphological, sedimentological, and vegetation characteristics were measured on a single nebkha formed by a Traganum moquinii plant located in the foredune of Caleta de Famara beach (Lanzarote, Canary Islands). Variables were sampled at 120 plots in a 0.5 × 0.5 m square grid. A two-step process using multiple linear regression (MLR) analyses was developed to characterize 1) the influence that morphological variables and distance from the sea have on plant and sediment patterns on nebkha, and 2) the influence of plants on depositional sediment characteristics. Results indicate close relationships between distance from the sea, plant coverage, and sediment patterns. Empirical results were used to develop a conceptual model that explains the spatial distribution of bio- and geo-morphological characteristics of an arid nebkha foredune.


Assuntos
Chenopodiaceae , Ecossistema , Modelos Teóricos , Plantas , Espanha
3.
Sci Rep ; 11(1): 4844, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649351

RESUMO

We report on a detailed study of an amplified spontaneous emission source operated in a pulsed regime with particular attention paid to the influence of high-intensity chaotic temporal events on the generation of nonlinear processes. To this aim, we have developed a monolithic high-power fiber system delivering partially coherent pulses of adjustable coherence. We also have demonstrated a non-linear method to characterize the stochastic properties of the source mitigating the bandwidth limitation of linear techniques. Measured parameters of the source for various configurations are presented. An enhanced classical model has been established to reproduce the statistical properties of the source and predict the behaviour when exciting non-linear processes. Finally, a non-linear process (second harmonic generation) is investigated comparing the efficiency when the process is pumped by a pulsed beam with maximal and low coherence.

4.
J Environ Manage ; 282: 111953, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33440317

RESUMO

The research hypothesis considered in this study is that decisions adopted on beach use and management in arid environments can result in significant changes in the biogeomorphological processes of the beach-dune system of which it forms part. Different information sources and geographical information systems were used to make a spatiotemporal analysis of possible correlations between the presence of beach equipment, services and uses in the backshore area of an arid beach-dune system, such as the beach named Playa del Inglés (Gran Canaria island, Spain) and environmental changes detected in the same area. The period considered in the study covers from 1961 (before the development of the mass tourism on the island) to 2018. Significant variations in vegetation cover over the course of the study period were detected, as well as an overall increase in erosion (topographic and erosive aeolian landforms) and foredune fragmentation and a decrease in geomorphological resilience. The study found not only relationships between management decisions and environmental impacts, but also that environmental impacts of management decisions on beach use made in the 1970s and 1980s continue to be felt today. Moreover, the results also reinforce the idea that management decisions made based on the results of scientific research studies (management-research binomial) can lead to more environmentally sustainable actions.


Assuntos
Conservação dos Recursos Naturais , Erosão do Solo , Tomada de Decisões , Ilhas , Espanha , Análise Espaço-Temporal
5.
Opt Lett ; 45(6): 1495-1498, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32164000

RESUMO

We report on a monolithic narrow spectral linewidth master oscillator power amplifier (MOPA) delivering up to 39 W around 976 nm with very high contrast. The amplifier is based on an ytterbium-doped large mode area (LMA) octagonal double clad (DC) active fiber with parameters optimized for long living three-level operation.

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