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A good understanding of the mechanisms and magnitude of the impact of invasive alien species on ecosystem services and biodiversity is a prerequisite for the efficient prioritisation of actions to prevent new invasions or for developing mitigation measures. In this review, we identified alien marine species that have a high impact on ecosystem services and biodiversity in European seas, classified the mechanisms of impact, commented on the methods applied for assessing the impact and the related inferential strength, and reported on gaps in available information. Furthermore, we have proposed an updated inventory of 87 marine species in Europe, representing 13 phyla, which have a documented high impact on ecosystem services or biodiversity.Food provision was the ecosystem service that was impacted by the greatest number of alien species (in terms of both positive and negative impacts). Following food provision, the ecosystem services that were negatively affected by the highest number of alien species were ocean nourishment, recreation and tourism, and lifecycle maintenance, while the ecosystem services that were most often positively impacted were cognitive benefits, water purification, and climate regulation. In many cases, marine aliens were found to impact keystone/protected species and habitats. Thirty percent of the assessed species had an impact on entire ecosystem processes or wider ecosystem functioning, more often in a negative fashion. Forty-nine of the assessed species were reported as being ecosystem engineers, which fundamentally modify, create, or define habitats by altering their physical or chemical properties.The positive impacts of alien species are probably underestimated, as there is often a perception bias against alien species. Among the species herein assessed as high-impact species, 17 had only negative and 7 only positive impacts; for the majority (63 species), both negative and positive impacts were reported; the overall balance was often unknown. Although there is no doubt that invasive species have modified marine ecosystems, evidence for most of the reported impacts is weak, as it is based on expert judgement or dubious correlations, while only 13% of the reported impacts were inferred via manipulative or natural experiments. A need for stronger inference is evident, to improve our knowledge base of marine biological invasions and better inform environmental managers.

Diatom floras were examined in a high-altitude geothermal field, 4200 -4500 m (29˚19'S 68˚W'), located in the Central Andean dry Puna ecoregion or southern Altiplano. These locations include hostile environments subjecting living organisms to extreme conditions. The aim of the present study was to investigate the spatial patterns and describe the response of diatom assemblages to differences in physical and chemical variables. Different shallow (<10 cm) aquatic systems with variable chemical and physical conditions (fumaroles, freshwater-saline rivers and swamps) were studied seasonally during 2011-2012. The conductivity exhibited high variability (360 to 18340 µS cm −1 ) among the systems studied, temperature was lower in rivers and swamps (6.8˚C -10˚C) and high in fumaroles stations (30˚C -37.5˚C), and pH was lower in fumaroles than freshwater systems (3.25 to 8.97). Statistical analyses suggest that the diatoms cluster into three major groups. The most common taxa include: Achnanthidium exiguum (Grunow) Czarnecki, Cocconeis placentula var. lineata (Ehrenberg) Van Heurck, Eolimna minima (Grunow) Lange-Bertalot, Staurosirella pinnata (Ehrenberg) Williams and Round, Navicula gregaria Donkin, Nitzschia inconspicua Grunow, Nitzschia palea (Kützing) Smith, Nitzschia perminuta (Grunow) Peragallo, and Planothidium lanceolatum (Brébisson ex Kützing) Lange-Bertalot. As expected, the 20 to 200 μm-size fraction contained the highest numbers of diatom taxa (53 species), although an unexpectedly high number (47 species) were also found in the smaller 5 to 20 μm-size fraction, more associated to fumaroles and saline systems. The 180 to 2000 μm size fraction contained only two species, including rosette-forming diatom Ulnaria ulna (Nitzsch) Compère, and the unicellular species Surirella chilensis Janisch, both species exclusively reported in freshwater systems. Canonical correspondence analysis (CCA) Other factors include substrate type, presence of macrophytes, current velocity and other local environmental conditions. The results presented here enhance our understanding of diatom richness/composition in hostile environments from a high-altitude arid and semi-arid geothermal region.

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In recent years Chile has experienced a significant increase in mining activities, which has resulted in an increase in waste generation. The dispersion of these residues in the air, water and soil has led to negative changes in the environment.This main objective of this study is to identify the influence of the copper mine Los Pelambres (station E2) located in the Choapa River Basin (IV Region Coquimbo). To achieve this goal we performed an analysis of the physical and chemical composition of sediment samples in the summer season taken from the rithron to potamon areas of the watershed. River sediments can provide information and influence the degree of pollution in a given area due to mining discharges. The analysis was based on two types of determinations: total metal content, which provides an assessment of the level of contamination, and studies of different chemicals in which the metal is associated with the sediment.The results of this study showed that station E2 (Cuncumen River) has a particular behavior in the basin, showing higher content of metallic trace elements; for example, the concentration of Cu (total fraction) was 4814.1 µgg -1 . In the rest of the stations the metal content was less than in E2 (total Cu from 42.4 µggin E1 to 136.2 µgg -1 in E5), therefore it is concluded that there is no direct influence of the mining activity of Los Pelambres station (E2) in the rest of the basin. BCR sequential extraction of sediments, developed under the auspices of the Community Bureau of Reference, indicated metal mobility. Metal mobility is closely associated with the chemical conditions of the system. In general, metals that could have greatest mobility in the basin are: Cu, Cd, Zn and Mn, found in the soluble acid fraction, together with oxidant (organic matter) and reducing (Fe and Mn oxides) conditions.The cluster analysis of the total fraction of metal content in sediments indicates that the mine discharge site (E2), has a unique behavior in the basin. Station E2 showed a similarity below 50%, while the rest of the basin showed a similarity above 70%.Overall the results indicate that the Los Pelambres Mine is not a direct source of heavy metals in the Choapa River Basin, which does not imply that station E2 (Cuncumen River) has no influence on the metal content of sediments. To determine the area of this season, the study area should be narrowed to Cuncumen River (E2) section of the Choapa River Basin, since the physical conditions of the system, hydrographic conditions and climatic do not allow a high rate of discharge and mobility of heavy metals from the mining area with high discharge to the last station (Huentelauquen).

Resumen S e realizó la caracterización del cultivo de Balsa (Ochoroma pyramidale), en la provincia de Los Ríos , Ecuador, durante el año 2008. Se determinó el establecimiento, manejo y comercialización de esta especie. Además se establecieron costos, ingresos, rentabilidad y punto de equilibrio del cultivo mediante encuestas a productores de balsa. Los resultados demuestran que los productores utilizan la semilla nativa procedente de Ecuador. El 53.50% compran las plántulas en viveros de la localidad mientras que el 46.50% realizan su propio vivero. Cabe destacar que los productores realizan labores de establecimiento y mantenimiento a sus cultivos, no obstante el 94.00% de ellos no reciben asistencia técnica, lo cual incide en la calidad de las plantaciones y su rendimiento. Se estableció que las superficies sembradas van desde 0.37 hasta 44.40 hectáreas; donde 34.25% pertenecen a plantaciones de un año; 32.54% son plantaciones de tres años y en menores porcentajes se encuentran cultivos de dos, cuatro y cinco años. Cuando han alcanzado una edad de tres a cuatro años, los árboles son comprados directamente en las fincas de los productores en forma de trozas y por camionada, por empresas de la localidad como son: PLANTABAL, INMAIA y BALSAFLEX, las mismas que exportan balsa procesada a mercados de Europa, Asia y Norteamérica. Los costos totales en cuatro años de producción en una hectárea de balsa ascienden a 2,477.06 dólares con ingresos de 6,000.00 dólares, obteniendo un beneficio neto de 3,522.94 dólares una rentabilidad de 142.00 por ciento y el punto de equilibrio en unidades físicas 22.80 m 3 de balsa y 912.10 dólares en unidades monetarias por hectárea.Palabras claves: balsa, viveros, plántulas, costo de producción, rentabilidad, punto de equilibrio AbstRAct A characterization of balsa (Ochoroma pyramidale) crop was made in the Los Ríos province Ecuador, during the 2008. The establishment, manage and commercialization of this specie was determined. Also the costs of production, incomes, profitability and the equilibrium point of this crop were determined through surveys made to the balsa planters. It was determined that producers use native seeds proceeding from Ecuador. 53.50% of the surveyed planters get their seedlings from local plant nursering while 46.50% get their seedlings from their own plant nursering. It is important to mention that planters do the establishment and maintenance labors of their crops by theirself, although 94.00% of them never has any technical assistance which is determining for the quality and yield of the crops. It was determined that the surface used to establish this crop oscilate from 0.37 to 44.40 hectares where 34.25% belongs to one year plantations, 32.54% to three years, and with the lower percentage crops of two, four and five years can be found. When the trees have reach an average age of three to four years they are directly bought at the planters' farm cutted in to pieces and transported by trucks by local enterprises as PLANTABAL, INMAIA and BALSAFLEX, whom process...

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La presente investigación estuvo dirigido a los emprendimientos informales dirigidos por mujeres en el cantón Quevedo, Provincia de Los Ríos. El fin fue establecer las determinantes que influyen para que una mujer participe laboralmente y se concentre en el comercio informal y establecer estrategias para mejorar sus negocios. Se aplicó estadística descriptiva. El universo estuvo conformado por el total de mujeres que se dedican al comercio informal en el cantón Quevedo; se aplicó un muestro probabilístico aleatorio a 136 negocios informales; se analizaron variables aleatorias continuas y discretas. Se determinó que la media en la edad de las mujeres que se dedican al comercio informal es de 41 años con un mínimo de 15 años y un máximo de 80 años; el 44,60% de mujeres se dedica a la venta de ropa siendo la actividad más representativa y en menor orden se encuentranemprendimientos de comida y calzado en un 16,11% y 11,37% en su orden. Así mismo se conoció que en un 90% las emprendedoras no realizan planes estratégicos para posicionarse en el mercado. Se concluye que es importante implementar estrategias competitivas enemprendimientos informales ya que crea el potencial de rendimiento que necesitan para obtener beneficios en el futuro.