Search results for "CAPE"

Leaps and bounds: geographical and ecological distance constrained the colonisation of the Afrotemperate by Erica.

2018

Abstract Background The coincidence of long distance dispersal (LDD) and biome shift is assumed to be the result of a multifaceted interplay between geographical distance and ecological suitability of source and sink areas. Here, we test the influence of these factors on the dispersal history of the flowering plant genus Erica (Ericaceae) across the Afrotemperate. We quantify similarity of Erica climate niches per biogeographic area using direct observations of species, and test various colonisation scenarios while estimating ancestral areas for the Erica clade using parametric biogeographic model testing. Results We infer that the overall dispersal history of Erica across the Afrotemperate…

Literature, social media and questionnaire surveys identify relevant conservation areas for Carcharhinus species in the Mediterranean Sea

2023

Sharks support ecosystems’ health, but their populations are facing severe declines worldwide. Knowledge gaps on shark distribution and the negative human perception of them still represent a barrier to the implementation of effective conservation measures. Here we carried out a regional-scale analysis in the Mediterranean Sea using data on requiem shark catches and sightings available in the scientific literature and on social media platforms to: 1) depict the distribution of Carcharhinus species across the basin, 2) identify potentially relevant areas for their conservation, and 3) evaluate people’s attitude toward shark protection. In addition, we administered 112 questionnaires in one o…

Local Extinction of Dragonfly and Damselfly Populations in Low- and High-Quality Habitat Patches

2010

Understanding the risk of extinction of a single population is an important problem in both theoretical and applied ecology. Local extinction risk depends on several factors, including population size, demographic or environmental stochasticity, natural catastrophe, or the loss of genetic diversity. The probability of local extinction may also be higher in low-quality sink habitats than in high-quality source habitats. We tested this hypothesis by comparing local extinction rates of 15 species of Odonata (dragonflies and damselflies) between 1930-1975 and 1995-2003 in central Finland. Local extinction rates were higher in low-quality than in high-quality habitats. Nevertheless, for the thre…

A comparison of three statistical methods for analysing extinction threat status

2013

SUMMARYThe International Union for Conservation of Nature (IUCN) Red List provides a globally-recognized evaluation of the conservation status of species, with the aim of catalysing appropriate conservation action. However, in some parts of the world, species data may be lacking or insufficient to predict risk status. If species with shared ecological or life history characteristics also tend to share their risk of extinction, then ecological or life history characteristics may be used to predict which species may be at risk, although perhaps not yet classified as such by the IUCN. Statistical models may be a means to determine whether there are non-threatened or unclassified species that s…

FEARSCAPES. SENTIMENTI DI PAURA, RETORICHE SULLA SICUREZZA E PIANIFICAZIONE URBANA NELLA CITTA' CONTEMPORANEA.

2012

Structural bias in population-based algorithms

2014

Abstract Challenging optimisation problems are abundant in all areas of science and industry. Since the 1950s, scientists have responded to this by developing ever-diversifying families of ‘black box’ optimisation algorithms. The latter are designed to be able to address any optimisation problem, requiring only that the quality of any candidate solution can be calculated via a ‘fitness function’ specific to the problem. For such algorithms to be successful, at least three properties are required: (i) an effective informed sampling strategy, that guides the generation of new candidates on the basis of the fitnesses and locations of previously visited candidates; (ii) mechanisms to ensure eff…

General framework for testing Poisson-Voronoi assumption for real microstructures

2020

Modeling microstructures is an interesting problem not just in Materials Science but also in Mathematics and Statistics. The most basic model for steel microstructure is the Poisson-Voronoi diagram. It has mathematically attractive properties and it has been used in the approximation of single phase steel microstructures. The aim of this paper is to develop methods that can be used to test whether a real steel microstructure can be approximated by such a model. Therefore, a general framework for testing the Poisson-Voronoi assumption based on images of 2D sections of real metals is set out. Following two different approaches, according to the use or not of periodic boundary conditions, thre…

Choice between alternative investments in agriculture: The role of organic farming to avoid the abandonment of rural areas

2015

Abstract Sicily has a long tradition in citrus fruit cultivation that, with vineyard and olive tree, represents the main Mediterranean tree crops. Since many Sicilian farmers in recent years have decided to abandon conventional lemon orchards, in this paper we have evaluated the financial sustainability of organic lemon production by comparing it with the conventional one. Financial analysis has been carried out in a case study on the northwestern coast of Sicily, considering a 50-year economic life of an orchard. The results, per hectare of area, showed a clear advantage of organic lemon orchard. This was due to fewer labor requirements and to greater market appreciation for organic produc…

Economic Adaptation to Risky Environment in the Late Middle Ages: The Case of the "Accrues" of the Doubs in Chaussin (Jura, France) from c. 1370 to c…

2017

Located along the meanders of the Doubs, the people of Chaussin had to deal with the particular impact of the river on their environment. Due to the impact of the Little Ice Age on water levels in the area, the Doubs sometimes had special floods, which frequently changed its course from the end of the fourteenth century. As a result, some lands were absorbed, and others emerged, which were called the “accrues.” From 1377 the first observation of lost lands appears in the accounts of the castellan, in a petition from landowners who did not want to pay taxes on these fields. More than twenty years later, in the first decade of the fifteenth century, the duke of Burgundy, facing the same situa…

Science, politics and image in Valencia: a review of urban discourse in the Spanish City

2003

Abstract In the urban sphere, discourse is fundamental to the social and political construction of urban reality. The urban landscape is, in part, a result of those discourses. It is, as Richard Schein suggests, a discourse materialized. The production of these discourses throughout urban history both represented and constructed urban reality at any given time. For much of history, the written word was central to such discursive representations, literary formulations and even biological metaphors that sought to interpret the city both for local inhabitants and outsiders. Today, the photographic image has usurped the former dominance of the word. This article uses archival research to trace …