Risk Analysis of Invasive Species Introduction in the Port of Arzew,by Calculation of Biofouling Surface on Ships’ Hulls

Historically, the biofouling of ships’ hulls has always been considered amongst the oldest mechanisms causing the introduction of marine invasive species. However, in the last few decades, studies have been oriented mainly towards the introduction of non-indigenous species via ballast water, at the expense of biofouling. In this study, an alternative approach that deals with this latter parameter as the main factor of the introduction of marine organisms is proposed. The biofouling surface area of all vessels which have made call at Arzew port in Algeria is calculated over a period of one year (2014). This parameter indicates the importance of the pressure of propagule that corresponds to the successful introduction effort of a species, since it is this submerged surface of the ship that hosts organisms and spreads them all over the world. We associate to each calculated biofouling surface a bioregion of origin, as well as other parameters such as the number of vessels, their maritime routes and the environmental similarity of Arzew port’s seawater and the other different bioregions. We highlight according to the bioregion, the surfaces that constitute a critical risk of the species introduction and those that constitute a minor risk The study showed that over a period of 1 year, 1313 ships from 28 different bioregions that have made call at Arzew port have accumulated a total wet surface corresponding to about nine million square meters. It is worth to mention that this field of research requires special attention from academics as it may lead to more effective methods to prevent future exotic species introductions.     

Improved weighted ensemble learning for predicting the daily reference evapotranspiration under the semi-arid climate conditions

Environmental Science and Pollution Research - Evapotranspiration is an important quantity required in many applications, such as hydrology and agricultural and irrigation planning. Reference...