Spatio‐temporal distribution of mutton snapper and dog snapper spawning aggregations in the South‐west Atlantic

Author(s):  
Aline R. França ◽  
George Olavo ◽  
Sergio M. Rezende ◽  
Beatrice P. Ferreira
2021 ◽  
Vol 56 (2) ◽  
pp. 220-233
Author(s):  
María Eugenia Fernández ◽  
Jorge Osvaldo Gentili ◽  
Ana Casado ◽  
Alicia María Campo

The objective of this work is to analyze the spatio-temporal distribution of Global Horizontal Irradiation (GHI) on a regional scale and its relationship with frequent synoptic situations in the south of the Pampeana region (Argentina). It was verified that the latitudinal pattern of distribution of the GHI is modified in the region by cloud cover, which is in turn determined by the seasonal dynamics of action centers and the passage of fronts in summer and winter. The South America Monsoon System (SAMS) defines differential situations of cloudiness and rainfall in the region, which affect GHI. GHI increased successively between the decades 1981–2010, a factor associated with the variability of rainfall that characterizes the region.


2007 ◽  
Vol 17 (4) ◽  
pp. 359-366 ◽  
Author(s):  
Agustina Gómez Laich ◽  
Marco Favero

AbstractThe White-chinned Petrel Procellaria aequinoctialis is the second most commonly captured species by Argentinean longliners. The severe declines that this species has experienced in some of its populations (e.g. South Georgia Islands) have been principally attributed to incidental mortality associated with longliners. In this study we analyse the spatio-temporal variability in the mortality rates of White-chinned Petrels on the Patagonian Shelf and the effects that environmental and operational variability have on such mortality. The average capture rate (± 1 SD) for the period 1999–2003 was 0.014 ± 0.090 White-chinned Petrels for every 1,000 hooks deployed. Higher capture rates were observed when short longlines were deployed. Capture rates were not affected by the wind speed or by the time to the full moon. The distribution of the captures differed throughout the year. During autumn–winter most captures took place in the north of the Patagonian Shelf, whereas during spring–summer incidental captures occurred principally to the south between 45°S and 50°S.ResumoEl Petrel Barba Blanca Procellaria aequinoctialis constituye la segunda especie más frecuentemente capturada por la flota palangrera Argentina. Los importantes decrecimientos poblacionales observados en algunas poblaciones de esta especie (e.g. Islas Georgias del Sur) han sido principalmente atribuidos a la mortalidad incidental asociada a embarcaciones palangreras. En este trabajo se analizó la variación espacio- temporal en las tasas de captura incidental del Petrel Barba Blanca a lo largo de la Plataforma Continental Argentina y se estudió el efecto que diferentes variables ambientales y operacionales tienen sobre la mortalidad incidental de esta especie. La tasa de captura promedio (± d.s) durante el periodo 1999–2003 fue de 0.014 ± 0.090 Petreles Barba Blanca cada 1.000 anzuelos. Mayores tasas de captura fueron registradas al utilizar palangres cortos. No se observó un efecto de la intensidad del viento ni de la distancia a la luna llena sobre las tasas de captura. La distribución de las capturas difirió a lo largo del aão. Durante el otoão-invierno la mayoría de las capturas estuvieron localizadas al norte de la Plataforma Continental Argentina, mientras que durante los meses de primavera-verano las capturas estuvieron localizadas principalmente entre los 45°S y 50°S.


2021 ◽  
Vol 40 (8) ◽  
pp. 133-144
Author(s):  
Xiangyu Long ◽  
Rong Wan ◽  
Zengguang Li ◽  
Yiping Ren ◽  
Pengbo Song ◽  
...  

As part of the research topic “Forecasting the variability of climate-vulnerable areas in Ukraine in the coming decades” (state registration number 0118U000554) a study of spatio-temporal distribution of ice category (dangerous) and SHP (spontaneous) was conducted in Ukraine at the present stage of climate change. The purpose of this article is to study the distribution of ice deposits of large diameters, namely dangerous (DHP) and spontaneous (SHP) in Ukraine during the current stage of climate change. It was also necessary to summarize the information on the identifi ed losses and their nature from ice deposits of the spontaneous (SHP) category, registered in some regions of Ukraine during this time. Main material. Dangerous ice deposits of the category are quite common in Ukraine and are observed almost every year. They are most common in the winter months (December-February) and in late autumn in November, when they are found in at least half of the regions. During 2011-2019, they were territorially observed in most oblasts, especially in the western, central and eastern regions. In the south, such deposits were mostly observed in Odesa, Mykolaiv, Kherson oblasts and the Autonomous Republic of Crimea. In April, such deposits were observed only in the Carpathian region of Transcarpathia in Playa. During October 2011-2019, dangerous ice deposits were found only in the Carpathian region (Zakarpatska and Ivano-Frankivsk regions), in some places in the center (Kirovohrad and Dnipropetrovsk regions) and in the south (Odessa, Mykolaiv, Kherson regions). Spontaneous ice deposition is observed in the territory not every month and year, but more o???? en in the cold period. The areas where they occur most o???? en are highlighted, namely in Transcarpathia at the Play weather station. However, there are places where such deposits also occurred quite often in the study period - in Lviv region (Kamyanka-Buzka, Rava-Ruska), Zhytomyr region (Olevsk, Zhytomyr), Mykolayiv region (Mykolayiv, Ochakiv), Donetsk region (Amvrosiyivka, Mariupol), Zaporizhzhia region (Zaporizhzhia, Huliaipole), the Autonomous Republic of Crimea (Chornomorske, Opasne, Simferopol). Damage from ice deposits of the SHP category was observed in 4 years out of 9 studied at the facilities of the industrial complex, transport and utilities. The largest number of losses was recorded in 2014. Conclusions. It was found that the most common dangerous ice deposits during 2011-2019 were in January, February, December, where they were observed in 10 to 14 regions, and especially in March in 21 region. They were most common in the western, central and eastern regions, and in the south in Odessa, Mykolaiv, Kherson regions and the Autonomous Republic of Crimea. Ice deposits of a spontaneous nature were mostly observed in the Zakarpatia region in Playa, as well as at some meteorological stations in Lviv, Zhytomyr, Mykolaiv, Donetsk, and Zaporizhzhia regions.


Author(s):  
Ronaldo A. Christofoletti ◽  
Camila K. Takahashi ◽  
Diogo N. Oliveira ◽  
Augusto A.V. Flores

Sedentary consumers play an important role on populations of prey and, hence, their patterns of abundance, distribution and coexistence on shores are important to evaluate their potential influence on ecosystem dynamics. Here, we aimed to describe their spatio-temporal distribution and abundance in relation to wave exposure in the intertidal rocky shores of the south-west Atlantic to provide a basis for further understanding of ecological processes in this system. The abundance and composition of the functional groups of sessile organisms and sedentary consumers were taken by sampling the intertidal of sheltered and moderately exposed shores during a period of one year. The sublittoral fringe of sheltered areas was dominated by macroalgae, while the low midlittoral was dominated by bare rock and barnacles. In contrast, filter-feeding animals prevailed at exposed shores, probably explaining the higher abundance of the predator Stramonita haemastoma at these locations. Limpets were more abundant at the midlittoral zone of all shores while sea urchins were exclusively found at the sublittoral fringe of moderately exposed shores, therefore, adding grazing pressure on these areas. The results showed patterns of coexistence, distribution and abundance of those organisms in this subtropical area, presumably as a result of wave action, competition and prey availability. It also brought insights on the influence of top-down and bottom-up processes in this area.


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