A synthesis of ENSO effects on drylands in Australia, North America and South America

Fundamentally, El Niño Southern Oscillation (ENSO) is a climatic and oceanographic phenomenon, but it has profound effects on terrestrial ecosystems. Although the ecological effects of ENSO are becoming increasingly known from a wide range of terrestrial ecosystems (Holmgren et al., 2001), their impacts have been more intensively studied in arid and semiarid systems. In this brief communication, we summarize the main conclusions of a recent symposium on the effects of ENSO in these ecosystems, which was convened as part of the First Alexander von Humboldt International Conference on the El Niño Phenomenon and its Global Impact, in Guayaquil, Ecuador, from 16–20 May 2005. Participants in the symposium shared results and perspectives from research conducted in North and South America and Australia, regions where the ecological effects of ENSO have been studied in depth. Although the reports covered a wide array of organisms and ecological systems (Fig. 1), a recurring theme was the strong increase in rainfall associated with ENSO events in dry ecosystems (during the El Niño phase of the oscillation in the Americas and the La Niña phase in Australia). Because inter-annual variability in precipitation is such a strong determinant of productivity in arid and semiarid ecosystems, increased ENSO rainfall is crucial for plant recruitment, productivity and diversity in these ecosystems. Several long-term studies show that this pulse in primary productivity causes a subsequent increase in herbivores, followed by an increase in carnivores, with consequences for changes in ecosystem structure and functioning that can be quite complex

Characterization of the Brazilian continental shelf adjacent to Rio Grande do Norte state, NE Brazil

This study focuses on the analysis of high-resolution seismic profiles, integrated with sedimentological, echosounder, SRTM and satellite image datasets, of the Brazilian continental shelf adjacent to the Rio Grande do Norte State, NE Brazil. Located in the northeast of Brazil, the State of Rio Grande do Norte is bounded by two main coastal and shelf systems: the eastern coastal-shelf, from the Sagi River to the Touros High, and the northern coastal-shelf, extending from Touros High to Tibau. This shelf represents a modern, highly dynamic mixed carbonate-siliciclastic system characterized by reduced width and shallow depths as compared with other parts of the Brazilian shelf. It has an average width of 40 km, the shelf-break lying at a depth of ~ 60 m. This shelf is subject to the full strength of the westerly South Equatorial current combined with high winds and moderate to high tides and waves. A sharply defined stratigraphic boundary, probably between the Pleistocene and Holocene deposits, is clearly to be observed in the seismic record. Incised-valleys extending from the main river mouths (e.g.the Potengi, Açu, and Apodi) to the shelf break dominate the area investigated and may indicate periods of lower sea level.Este estudo está direcionado ao conhecimento da plataforma continental brasileira adjacente ao Estado do Rio Grande do Norte, NE do Brasil, através da analise de perfis sismicos de alta resolução integrados a dados sedimentológicos, batimétricos, SRTM e imagens de satélites. O Estado do Rio Grande do Norte, localizado no nordeste do Brasil, apresenta dois sistemas costeiros-plataformais: Setor Este, do Rio Sagi (divisa PB-RN) ao Alto de Touros e Setor Norte, do Alto de Touros a Tibau (divisa RN-CE). Esta plataforma representa um sistema plataformal moderno misto (carbonático-siliciclástico), altamente dinâmico. É caracterizado por sua reduzida largura e águas rasas, quando comparado com outras partes da plataforma brasileira. A plataforma apresenta largura média de 40 km e a sua quebra encontra-se a profundidades médias de 60 m. A plataforma é sujeita a ação da corrente sul equatorial, combinada a ventos fortes e variação de maré moderada a alta e/ou ondas. Um limite estratigráfico fortemente definido, provavelmente entre os depósitos Pleistocênicos e Holocênicos, pode ser bem observado e vales incisos, estendendo-se a partir dos principais rios (como por ex., Potengi, Açu e Apodi) dominam a área investigada

Whispering-gallery-mode sensors for biological and physical sensing

This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this recordThe term whispering gallery mode (WGM) was first introduced to describe the curvilinear propagation of sound waves under a cathedral dome. The physical concept has now been generalized to include light waves that are continuously reflected along the closed concave surface of an optical cavity such as a glass microsphere. The circular path of the internally reflected light results in constructive interference and optical resonance, a morphology-dependent resonance that is suitable for interferometric sensing. WGM resonators are miniature micro-interferometers that use the multiple-cavity passes of light for very sensitive measurements at the microscale and nanoscale, including single-molecule and ion measurements. This Primer introduces various WGM sensors based on glass microspheres, microtoroids, microcapillaries and silicon microrings. We describe the sensing mechanisms, including mode splitting and resonance shift, exceptional-point-enhanced sensing and optomechanical and optoplasmonic signal transductions. Applications and experimental results cover in vivo and single-molecule sensing, gyroscopes and microcavity quantum electrodynamics. We also discuss data analysis methods and the limitations of WGM techniques. Finally, we provide an outlook for molecule, in vivo and quantum sensing.Engineering and Physical Sciences Research Council (EPSRC)Royal SocietyEuropean Union Horizon 2020Slovenian Research Agency (ARRS)US National Institutes of HealthNational Institute of Allergy and Infectious Diseases (NIAID)Okinawa Institute of Science and Technology Graduate University (OIST

Numerical and functional response of burrowing owls to long-term mammal fluctuations in Chile

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