65 research outputs found
A review of recent and future marine extinctions
Between 20 and 24 marine extinctions, ranging from algal to mammal species, have occurred over the past 500 years. These relatively low numbers question whether the sixth mass extinction that is underway on land is also occurring in the ocean. There is, however, increasing evidence of worldwide losses of marine populations that may foretell a wave of oncoming marine extinctions. A review of current methods being used to determine the loss of biodiversity from the world’s oceans reveals the need to develop and apply new assessment methodologies that incorporate standardized metrics that allow comparisons to be made among different regions and taxonomic groups, and between current extinctions and past mass extinction events. Such efforts will contribute to a better understanding of extinction risk facing marine flora and fauna, as well as the ways in which it can be mitigated
Recovery of green turtle populations and their interactions with coastal dune as a baseline for an integral ecological restoration
Antecedentes y Objetivos: La restauración ecológica se ha centrado en los componentes físicos y vegetales de los ecosistemas, y ha dejado de lado a la fauna silvestre y sus interacciones. Chelonia mydas es un macroherbívoro en peligro de extinción que anida en playas de México y Cuba, e influye en la vegetación costera con aportaciones de materia orgánica. Los objetivos de este estudio fueron analizar su recuperación poblacional, un índice del verdor de la vegetación de duna, así como la cantidad de materia orgánica estimada de sus nidadas antes y después de la implementación de una Norma Oficial Mexicana.
Métodos: Se analizaron datos de entre dos y tres décadas de monitoreo biológico en 16 playas de anidación de Chelonia mydas; a partir de ellos se realizaron tres niveles de análisis de indicadores demográficos, la aportación de materia orgánica de las tortugas en la playa y el vigor vegetal a partir de sensores remotos, además de aplicar los estadísticos pertinentes.
Resultados clave: Hubo un crecimiento exponencial del número de anidaciones de tortuga verde (entre 12 y 14% anual), asociado con pulsos de reclutamiento poblacional en los años 2000 y 2008. El aporte de materia orgánica a la playa fue significativamente mayor después de un cambio en la estrategia para manejo de las nidadas en México, y se detectó un incremento en el verdor de la vegetación de duna en zonas de anidación alta de Chelonia mydas.
Conclusiones: El incremento de las poblaciones de tortuga verde lleva a reflexionar acerca de las implicaciones que tiene la recuperación de especies de fauna sobre otras comunidades en los ecosistemas que habitan, lo que demanda el análisis de los paradigmas actuales y la adaptación de estrategias que atiendan sus necesidades de manejo, procurando las condiciones de integridad ecológica de sus hábitats.Background and Aims: Ecological restoration has focused on the physical and vegetation components of ecosystems, leaving aside studies on wild fauna and their interactions. Chelonia mydas is an endangered macroherbivore that nests on sandy beaches of Mexico and Cuba, and influences the coastal vegetation with organic matter contributions. The objectives of this study were to analyze its population recovery, a greenness index for dune vegetation, and the amount of organic matter estimated from its clutches before and after the implementation of an official Mexican norm.
Methods: Biological data obtained from two and three decades of monitoring 16 Chelonia mydas nesting beaches were analyzed; based on these, three levels of demographic indexes were carried out, the contribution of organic matter by marine turtles to the beach and the vegetal vigor using remote sensing, besides implementing the pertinent statistical analysis.
Key results: There was an exponential increase of the green turtle nests (between 12 and 14% per year), associated with population recruitment pulses in 2000 and 2008. The contribution of organic matter to the beach was significantly higher after a change in clutches management in Mexico, and an increase in the dune vegetation greenness was detected in high Chelonia mydas nesting zones.
Conclusions: The increase of the green turtle populations invites to reflex about the implications of the recovery of species of fauna have on other communities in the ecosystems they inhabit, demanding the analysis of the actual paradigms and the adaptation strategies that attend their management needs, procuring the ecological integrity conditions of their habitats
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
Marine extinctions-sticking to the fact?
In this article, Pablo del Monte Luna from the Centro Interdisciplinario de Ciencias Marinas in Mexico, reviews thestatus of marine extictions around the world and questions whether the terms is sometimes overuse
Who are more vulnerable to extinction, tetrapods or fish
ArtículosEn el medio terrestre, las extinciones se cuentan por centenas; en el marino, en cambio, se tiene documentada a lo más una docena de casos. Proponemos que esta diferencia se debe al simple hecho que los peces habitan en un medio ajeno, hostil y muchas veces inaccesible al humano. Se prueba que el riesgo de extinción en los tetrápodos depende en buena medida del tamaño (peso) pero en peces está determinado por el grado de encubrimiento. En este sentido, aquellas especies marinas que en algún momento de su ciclo de vida dejan de contar con la protección que les brinda el océano (peces anádromos) resultaron ser las más vulnerables. Es posible que dicha característica, aunada a la preferencia natural del humano hacia los grandes vertebrados terrestres, no permita contar con información completa de las especies y haga poco efectivos los criterios actuales utilizados para reclutar a los peces marinos en las filas de la conservación.Extinctions of terrestrial vertebrates are counted in hundreds. Conversely, in the marine realm there are at the most a dozen cases. We propose that this difference is due to the fact that fish inhabit a radically different environment, hostile and many times inaccessible to humans. We confirmed that the risk of extinction in tetrapods depends to a large extent on the body size (weight) but in fish is determined by the degree of concealment. In this sense, those marine species that during part of their life cycle are no longer protected by ocean waters (anadromous fish) resulted to be more vulnerable. It is possible that this attribute, in addition to the natural preference of humans for large terrestrial vertebrates, does not allow gathering complete information about the species, making out of IUCN current listing criteria an ineffective way to include marine fishes into conservation charts
Caracterización del centro de actividad biológica del Golfo de Ulloa, B.C.S. bajo un enfoque de modelación ecológica
IMPRESO Y PD
Confrontación de modelos de biomasa dinámica: Una aplicación a la pesquería del huachinango.
impreso y digita
Caracterización del centro de actividad biológica del Golfo de Ulloa, B.C.S., bajo un enfoque de modelación ecológica
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