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Jan Vicente Sven Zea Ryan J. Powell Joseph R. Pawlik Russell T. Hill 《Marine Biology》2014,161(12):2803-2818
Three new cases of sponge symbiosis between species of Plakortis and Xestospongia were found in reef caves and mesophotic reef habitats of the Caribbean. Plakortis sp. 1 from the Bahamas associates exclusively with Xestospongia deweerdtae which was originally described living freely on the deep fore-reef and caves of Jamaica. In addition, we found Plakortis sp. 2 from Puerto Rico which associates with both X. deweerdtae and a different Xestospongia sp. Sponge specimens were identified using cytochrome oxidase subunit 1, 28S rRNA and 18S rRNA gene sequence fragments, spicule analysis, and histological sections with SEM. Unlike previous sponge pairs, Xestospongia spp. not only grew as a thin veneer of tissue over the Plakortis host sponge but through the mesohyl, forming inner channels (0.1–1 cm) that may provide a benefit by facilitating more efficient water transport through the dense Plakortis tissue. Symbioses with both Plakortis spp. were documented from an early recruit stage through adulthood. Spicule measurements conducted on symbiotic versus free-living X. deweerdtae revealed significantly smaller spicule sizes for symbiotic individuals, suggesting a cost in terms of silicon availability, or a benefit in terms of a lower investment in skeleton synthesis for support. This study reveals new specialized symbiotic associations between distantly related sponge genera that likely represent an alternative strategy of adaptation for life in reef caves and mesophotic reefs. 相似文献
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Häring Ivo Fehling-Kaschek Mirjam Miller Natalie Faist Katja Ganter Sebastian Srivastava Kushal Jain Aishvarya Kumar Fischer Georg Fischer Kai Finger Jörg Stolz Alexander Leismann Tobias Hiermaier Stefan Carli Marco Battisti Federica Makri Rodoula Celozzi Giuseppe Belesioti Maria Sfakianakis Evangelos Agrafioti Evita Chalkidou Anastasia Papadakis George Fuggini Clemente Bolletta Fabio Neri Alberto Giunta Guiseppe Scheithauer Hermann Höflinger Fabian Schott Dominik J. Schindelhauer Christian Köhler Sven Linkov Igor 《The Environmentalist》2021,41(2):286-329
Environment Systems and Decisions - Organizational and technical approaches have proven successful in increasing the performance and preventing risks at socio-technical systems at all scales.... 相似文献
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Martin?OlofssonEmail author Sven?Jakobsson Christer?Wiklund 《Behavioral ecology and sociobiology》2012,66(2):209-215
Morphological and behavioural traits can serve as anti-predator defence either by reducing detection or recognition risks,
or by thwarting initiated attacks. The latter defence is secondary and often involves a ‘startle display’ comprising a sudden
release of signals targeting more than one sensory modality. A suggested candidate for employing a multimodal defence is the
peacock butterfly, Inachis io, which, by wing-flicking suddenly, produces sonic and ultrasonic sounds and displays four large eyespots when attacked. The
eyespots make small birds retreat, but whether the sounds produced thwart predator attacks is largely unknown. Peacocks hibernate
as adults in dark wintering sites and employ their secondary defence upon encounter with small rodent predators during this
period. In this study, we staged predator–prey encounters in complete darkness in the laboratory between wild mice, Apodemus flavicollis and Apodemus sylvaticus, and peacocks which had their sound production intact or disabled. Results show that mice were more likely to flee from sound-producing
butterflies than from butterflies which had their sound production disabled. Our study presents experimental evidence that
the peacock butterfly truly employs a multimodal defence with different traits targeting different predator groups; the eyespots
target birds and the sound production targets small rodent predators. 相似文献
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Uwe Heiser Stefan Norra Doris Stüben Magnus von Wagner 《Environmental Sciences Europe》1999,11(2):73-78
For the application of our method for the sequential extraction of heavy metals from microsamples presented in part 1 (“Sequentielle Schwermetallextraktion von Mikroproben” — “Sequential Extraction of Heavy Metals from Micro Samples”) an investigation was carried out to evaluate airborne dust fallout and street sediments at two urban sites where different heavy metal immission rates occur due to traffic influence. In the street sediments the total concentrations of zinc, copper and lead was three to fivefold higher in the silt and clay fraction (< 63 μm) than in the particle size fraction (< 1,12 mm), but showed nearly the same mobilisation behaviour. The dust samples showed equal mobilisation behaviour as the street sediments for copper and lead, while zinc was considerably more mobile in the dust samples: In extraction steps I–IV (I: mobile fraction; II: easily deliverable fraction; III: fraction bound to manganese oxides; IV: fraction bound organic to matter) zinc, copper and lead in street sediments, as well as copper and lead in dust samples, were dissolved to 40–70%, whereas about 80% of zinc in the dust samples was already dissolved in extraction step I. 相似文献
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联邦德国为了降低矿物燃料的消耗并减少CO2的排放量,在发展和利用再生能源方面作出了巨大的努力。本文阐述了德国可再生能源的利用现状,分析了利用可再生能源的技术,经济方面的问题,讨论了减少CO2排放理的有效方法。 相似文献
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Wamba Alfred G. N. Lima Eder C. Ndi Sylvere K. Thue Pascal S. Kayem Joseph G. Rodembusch Fabiano S. dos Reis Glaydson S. de Alencar Wagner S. 《Environmental science and pollution research international》2017,24(27):21807-21820
Environmental Science and Pollution Research - Natural pozzolan is an amorphous silicate-based material of volcanic origin. In this work, the natural pozzolan was modified by using... 相似文献