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Acta Oceanologica Sinica 2022年第12期41卷 152-155页

作者： Leonardo Campos Fernando Berrios Brenda BHermosillo-Núñez Marco Ortiz departamento de Ciencias Acuáticas y ambientales Universidad de Antofagasta ChileAntofagasta 1240000Chile centro de Investigaciones Costeras Universidad de Atacama(CIC-UDA) Avenida Copayapu 485Copiapó1530000Chile Laboratorio de Modelamiento de Sistemas Ecológicos Complejos(LAMSEC) Instituto AntofagastaUniversidad de AntofagastaAntofagasta 1240000Chile Instituto de Ciencias Naturales AvH Facultad de Ciencias del Mar y Recursos BiológicosUniversidad de AntofagastaAntofagasta 1240000Chile centro de Investigación y estudios Avanzados del Maule Vicerrectoría de Investigación y PosgradoUniversidad Católica Del MauleCampus San MiguelTalca 3480094Chile

We report for the first time the presence of local populations of the starfish Odontaster penicillatus in the regions of Atacama and Antofagasta,Chile.This finding indicates an extension of the distribution limit of 500 km with respect to the last observation made in 2007 in Isla Grande de Atacama.A total of 121 specimens of O.penicillatus were recorded at depths of between 8 m and 24 m.They were associated with rocky substrate and with different species of barnacles,sponges and bryozoans.The presence of O.penicillatus expands the knowledge of the benthic biodiversity of the region,and the development of studies on its ecological importance will be promoted.

关键词： Odontaster penicillatus new record Antofagasta Atacama South Pacific Ocean

Stipa tenacissima Does not Affect the Foliar δ^(13)C and δ^(15)N of Introduced Shrub Seedlings in a Mediterranean Semi-arid Steppe

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Journal of Integrative Plant Biology 2006年第8期48卷 897-905页

作者： Fernando T.Maestre Susana Bautista Jordi Cortina departamento de Ecologia Universidad de AlicanteApartado de correos 9903080 AlicanteSpain department of Biology Duke UniversityPhytotron BuildingScience DriveBox 90340DurhamNorth Carolina 27708-0340USA Centro de Estudios Ambientales del Mediterraneo C/ Charles Darwin 1446980 PaternaSpain

Recent studies have shown that the tussock grass Stipa tenacissima L. facilitates the establishment of late-successional shrubs, in what constitutes the first documented case of facilitation of woody plants by grasses. With the aim of increasing our knowledge of this interaction, in the present study we investigated the effects of S. tenacissima on the foliar δ13C, δ15N, nitrogen concentration, and carbon ： nitrogen ratio of introduced seedlings of Pistacia lentiscus L., Quercus coccifera L., and Medicago arborea L. in a semi-arid Mediterranean steppe. Six months after planting, the values of δ13C ranged between -26.9‰ and -29.6‰, whereas those of δ15N ranged between -1.9‰ and 2.7‰. The foliar C ： N ratio ranged between 10.7 and 53.5, and the nitrogen concentration ranged between 1.0% and 4.4%. We found no significant effect of the microsite provided by S. tenacissima on these variables in any of the species evaluated. The values of δ13C were negatively correlated with predawn water potentials in M. arborea and were positively correlated with relative growth rate in Q. coccifera. The values of δ15N were positively correlated with the biomass allocation to roots in the latter species. The present results suggest that the modification of environmental conditions in the are surrounding S. tenacissima was not strong enough to modify the foliar isotopic and nitrogen concentration of shrubs during the early stages after planting.

关键词： facilitation Medicago arborea Pistacia lentiscus Quercus coccifera stable isotopes steppe Stipa tenacissima.

Mercury levels in human population from a mining district in Western Colombia

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Journal of Environmental Sciences 2018年第6期30卷 83-90页

作者： Harry Gutiérrez-Mosquera S.B.Sujitha M.P.Jonathan S.K.Sarkar Fairy Medina-Mosquera Helcias Ayala-Mosquera Gladis Morales-Mira Laura Arreola-Mendoza Facultad de Ingenieria Universidad Tecnologica del Choco Carrera 22 No.18B-10 Quibdo Colombia centro Interdisciplinario de Investigaciones y estudios sobre Medio Ambiente y desarrollo (CIIEMAD) Instituto Politecnico Nacional (IPN) Calle 30 de junio de 1520 Barrio la Laguna Ticomdn Del. Gustavo A. Madero C.P.07340 Ciudad de Mexico Mexico department of Marine Science University of Calcutta 35 Ballygunge Circular Road Calcutta 700 019 India Instituto de Investigaciones ambientales del Pacifico (IIAP) Carrera 6 No. 37-39 quibdo Colombia Facultad de Ingenieria Uniuersidad de Medellin Carrera 87 No. 30-65 Medellin Colombia

A biomonitoring study was carried out to examine the adverse impacts of total mercury in the blood（HgB）, urine（Hg U） and human scalp hair（HgH） on the residents of a mining district in Colombia. Representative biological samples（scalp hair, urine and blood） were collected from volunteered participants（n = 63） to estimate the exposure levels of THg using a Direct mercury analyzer. The geometric mean of THg concentrations in the hair,urine and blood of males were 15.98 μg/g, 23.89 μg/L and 11.29 μg/L respectively, whereas the females presented values of 8.55 μg/g, 5.37 μg/L and 8.80 μg/L. Chronic urinary Hg（HgU）levels observed in male workers（32.53 μg/L） are attributed to their long termed exposures to inorganic and metallic mercury from gold panning activities. On an average, the levels of THg are increasing from blood（10.05 μg/L） to hair（12.27 μg/g） to urine（14.63 μg/L）.Significant positive correlation was found between hair and blood urinary levels in both male and female individuals. Thus the present biomonitoring investigation to evaluate the Hg levels and associated health issues would positively form a framework for further developmental plans and policies in building an ecofriendly ecosystem.

关键词： Humans Mercury Gold panning Biomarkers Toxicity Colombia

Head geometric morphometrics of two Chagas disease vectors from Venezuela

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Zoological Systematics 2017年第1期42卷 65-70页

作者： Ana Maria Oropeza Carlos Arturo Perri Fernanndez Jonathan Liria Ana Soto-Vivas Escuela de Bioanalisis Facultad de Cieneias de la Salud Universidad de Carabobo Venezuela Universidad Regional Amazonica IKIAM km 7 via Muyuna Ecuador centro de Esmdios en Zoologla Aplicada Facultad Experimental de Ciencias y Tecnologla Universidad de Carabobo Venezuela centro de estudios de Enfermedades Endkmicas y Salud Ambiental Institeto de Alto Estudios "Dr. Arnoldo Gabladon " Venezuela Carrera de Cs. Biologicas y ambientales Facultad de Ciencias Biologicas Universidad Central del Ecuador Ecuador

Triatominae species are considered the main vectors of Chagas disease or American Trypanosomiasis. In Venezuela, the principal vectors are Rhodnius prolixus （Stal, 1959） and Triatoma maculata （Erichson, 1848）, which are belonged to the tribe Rhodniini and Triatomini, respectively. The head conformation and size development of these species can reflect ontogenetic changes which contribute with the vectors biology studies, as well to support of instars determination. The goal of the paper is to the application of geometric morphometric techniques for describing head conformation and size of instars of these species. We photographed 140 heads in R. prolixus： First instar （I： 16）, second instar （II： 17）, third instar （III： 18）, fourth instar （IV： 21）, fifth instar （V： 21）, adult female （F： 26） and adult males （M： 21）; in T. maculata heads of 136 specimens were photographed,I： 20, II： 17, III： 26, IV： 15, V： 19, F： 20 and M： 19. Landmark coordinate （x, y） configurations were registered and aligned by Generalized Procrustes Analysis. Covariance Analyses were implemented with proportions of re-classified groups and MANOVA. Statistical analyses of variance found not significant differences in head isometric size （Kruskal-Wallis） among IV and V instars in both species. The a posteriori re-classification was almost perfect in R. prolixus （82%） and T. maculata （86%）; the main head differences occurs in antenniferous tubercles, postocular and preocular. Our study using quantitative tools for describing the shape differences contributes to explain the morphology variability and development of Chagas disease vectors.

关键词： Instars Rhodniini Triatomini conformation centroid size.

Positive interactions by cushion plants in high mountains:fact or artifact?

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Journal of Plant Ecology 2016年第2期9卷 117-123页

作者： Marco A.Molina-Montenegro Rómulo Oses Ian S.Acuña-Rodríguez Cristian Fardella Ernesto I.Badano Patricio Torres-Morales Jorge Gallardo-Cerda Cristian Torres-Díaz Instituto de Ciencias Biológicas Universidad de TalcaAvda.Lircay s/nTalcaChile centro de estudios Avanzados en ZonasÁridas(CEAZA) Facultad de Ciencias del MarUniversidad Católica del NorteCoquimboChile División de Ciencias ambientales Instituto Potosino de Investigación Científica y TecnológicaCamino a la Presa San José2055Colonia Lomas ta Sección CP 78216San Luis PotosíSLPMéxico 4 Instituto de Ciencias Ambientales y EvolutivasUniversidad Austral de ChileValdiviaChile departamento Científico Instituto Antártico Chileno(INACH)Punta ArenasChile Laboratorio de Genómica y Biodiversidad(LGB) Departamento de Ciencias NaturalesUniversidad del Bío-BíoChillánChile

Positive interactions are defined as non-trophic interactions where at least one of the interacting species is benefited in terms of fitness and the other remains unaffected.Nevertheless,the bidirectional feedbacks between species may be positive,neutral or negative.Thus,if facilitated species induce negative effects on their‘nurses’,the assumed definition of positive interactions could be reconsidered.Methods We assessed if ecological interactions between cushions of Azorella madreporica and their facilitated species are positive.Specifically,we tested if cover of facilitated species has any costs for cushion plants from an ecophysiological perspective,and if these costs increase with the amount of cover of facilitated species.In addition,through pathway analysis and correlations,we assessed if cover and richness of facilitated species have a direct and/or indirect effect on the fitness of cushion plants.Important Findings We found that facilitated plant species induced a significant cost for their nurses(cushion plants),and this cost increases with cover of the facilitated species.Additionally,the facilitated species exert a strong direct negative effect on the cushion’s fitness and a moderate indirect negative cost evident through the nutrient status and physiological performance of cushion plants.We thus contribute evidence that positive interactions between high mountain cushion plants of central Chile and their‘facilitated’species may be an artifact more than a fact,especially when bidirectional effects are considered;contrasting with the majority of studies that document only one side of the interaction.

关键词： cushion plants facilitation nurse effect positive interactions stress gradient hypothesis