Kelps dominate rocky shores in temperate latitudes, acting as important foundation species. Recently, kelp forests have received growing attention for their decline around the world. Climate change is one of the main drivers of their deforestation, both through abiotic stress and/or distortion of biotic interactions. In NW Spain, golden kelp (Laminaria ochroleuca) forests have recently declined in some areas due to excessive grazing. To further investigate the mechanisms behind this decline, a thorough 1-year seasonal demographic study was carried out on eight golden kelp reefs: four healthy and four degraded by herbivory. Kelps covered the full range of size classes throughout the year on healthy reefs. By contrast, only small, newly recruited kelps were found on degraded reefs in spring-summer, because excessive herbivory in autumn-winter caused a total collapse of kelp populations on a reef-scale (i.e., all kelps reduced to inviable stubs with no blade and no growth meristem). Bite marks in kelps covering all size classes showed that fishes, instead of invertebrates, were the culprits of the excessive herbivory. Recent studies, mostly conducted in the Indo-Pacific, also found that fish herbivory, alone or in combination with abiotic stressors, can maintain a canopy-free state in kelp reefs. To the best of our knowledge, this is the first time that fish is also shown to cause the collapse of entire kelp forests on a reef scale in the temperate Atlantic. The implications of this finding for the management and potential recovery of degraded reefs are discussed.
Although aquaculture sometimes lessens the negative effects of fishing by lowering the need to capture wild animals and plants, some aquaculture practices still require the exploitation of wild populations. A largely overlooked case is the use of wild populations to provide seed to sea farms. Mussel farming in Northwest Spain involve the capture of thousands of tons of young mussels (0.5–2 cm long) from the nearby rocky intertidal every year to supply floating rafts. Despite its volume, the impact of this activity on other sessile organisms remains unassessed. To fill this gap in our knowledge, we monthly monitored the sessile intertidal assemblage of five protected and six exploited sites during the closed season in 2016 following a nested sampling plan. Like the by-catch typical of other fisheries, harvesting young mussels for aquaculture was detrimental to the abundance and diversity of the associated sessile assemblage not directly targeted by this activity. Coverage and richness were also significantly lowered by the exploitation of mussel seed, and the community structure of protected and exploited sites was significantly different. These differences continued until the next open season, suggesting that the closed season was too short for the recovery of the associated non-target sessile assemblage. Given the size of the local mussel industry, the incomplete recovery along the closed season implies that mussel aquaculture must be putting a sustained pressure on a sizeable portion of the rocky intertidal of Northwest Spain.
Estado nutricional y aspectos familiares en niños peruanos con VIH en la era TARAA 87Ciencia y Desarrollo 16 (1), Enero-Junio 2013. 87:94Estado nutricional y aspectos familiares en niños peruanos con VIH en la era TARAA Nutritional Status and Family issues in Children Peruvian with HIV in the HAARTEdwin Miranda 1 , Sonia Farfán 2 , Sara Barrientos 3 , Lizzet Lara 4 , Doris Coz 5 RESUMENObjetivo: Describir el estado nutricional y aspectos familiares en niños con VIH en la era TARAA, en un país en estadio de epidemia concentrada del VIH con acceso gratuito a tratamiento antirretroviral.Material y Métodos. Estudio retrospectivo se revisaron historias clínicas, estudiamos a los niños con infección de VIH, por trasmisión vertical, que iniciaron TARAA entre 2007 a 2009 en un hospital pediátrico de Perú. Se comparó con un grupo control no infectados VIH para determinar el riesgo de desnutrición.Resultados: De los 75 niños enrolados, 34 (45%) fueron hombres, el promedio de edad de inicio de TARAA fue 3,6 años, la mediana de carga viral de log 5,14 copias/ml. Los niños con inmunodepresión severa (CD4<25%) fue el 68,0% (51/75), el 15% ha sufrido la pérdida de algún padre, el 36% recibe el cuidado de algún miembro de la familia diferente a los padres o viven en orfanatos, el 20% son hijos de madres solteras y el porcentaje de los niños con VIH con algún grado de desnutrición es de 69,3%, siendo el peso bajo para la edad más frecuente con el 66,7%, esto resulta un OR de 6,2 y 10,5 respectivamente.Conclusión: Existe un riesgo elevado de déficit de estado nutricional especialmente en el peso para la edad en los niños con VIH al momento de su diagnóstico. Muchos niños con VIH presentan nuevas formas de convivencias bajo el cuidado de sus familiares u orfanatos que lo hacen propensos a la dificultad en la inserción social. Results: Of the 75 children, 34 (45%) were male, the average age of onset of HAART was 3.6 years, the median viral load of 5.14 log copies/ml, children with severe immunodeficient (CD4 <25% ) was Palabras Claves: HIV, niños, TARAA
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