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1.
In this first attempt to survey the Brazilian sponge-dwelling fishes we present a list of collected fishes, with notes on their distribution, abundance and habitat preferences. Risor ruber, an obligate sponge-dwelling goby, and Scorpaenodes tredecimspinosus, never before collected in association with sponges, are recorded for the first time in the western South Atlantic based on collections made in localities on the northeastern Brazilian coast. Previous work on Risor ruber indicated that it preferred massive sponges, but in our study the majority of the specimens were found in the lumen of tubular sponges, Aplysina lacunosa, together with other fishes and invertebrates, mostly crustaceans. Elacatinus figaro, originally described as a cleaner goby, is also a sponge-dweller that occurs in waters much deeper than previously thought. The sponge community off northeastern Brazil represents the only shelter for several species of fishes in a desert of rubble and flat rocky bottoms, perhaps functioning as habitat oases. We also found four Brazilian endemic species of fishes associated with sponges in depths greater than 50m, which contradicts a previous hypothesis suggesting that endemic fishes in Brazilian coastal waters are restricted to depths less than 50m.  相似文献   

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Synopsis Elasmobranch nurseries are habitats where females give birth to their young and juveniles spend their early life history. Hypotheses concerning nurseries suggest that these provide the young a better source of food and protection against predation, however the degree of exposure to predatory risk in nursery areas vary. According to Branstetter hypothesis, slow growing species are either born at relatively large sizes or use protected nursery grounds, whereas faster growing species tend to rely more on growth rates than others factors. Primary nurseries are habitats where parturition occurs and in which the young live for a short time and secondary nurseries are habitats in which juveniles are found after leaving the primary nursery and before reaching maturity. Rhizoprionodon porosus and Carcharhinus acronotus use coastal waters off Cai?ara do Norte as both primary and secondary nurseries, while Carcharhinus limbatus makes use of the area as a seasonal primary nursery in late spring and early summer. C. falciformis apparently makes use of the end of inner continental shelf and the outer continental shelf as a primary nursery. Gymnura micrura, Rhinobatos percellens and Narcine brasiliensis makes use of coastal and turbid waters of region as both primary and secondary nurseries throughout the year, while Dasyatis guttata utilizes the area as a primary nursery. Aetobatus narinari and Rhinoptera bonasus, although caught in lesser number, appear to use the region as both primary and secondary nurseries and only primary nursery respectively. Dasyatis marianae (endemic from Northeastern Brazil) may use coastal sandbanks as a primary nursery, while Dasyatis Americana apparently exploits waters about 10 – 20 m in depth with rocky reef substrate only as secondary nursery. There was a measurable degree of temporal and spatial separation among sharks’ species, which may effectively create separate ecological niches, whereas among rays, with the exception of the stingray D. marianae, a spatial and temporal overlaps were observed. The Branstetter’s hypothesis was supported.  相似文献   

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Summary Genetic heritability in this triracial population is 0.41 for systolic pressure in children, 0.14 for systolic pressure in adults, and 0.34 for diastolic pressure in both generations. Cultural inheritance is much smaller, and there is no evidence of maternal effects or major loci.  相似文献   

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The chromosomes of 15 species of Iridaceae of the genera Alophia, Cipura, Eleutherine, Neomarica and Trimezia (subfamily Iridoideae) were examined after conventional Giemsa staining. The karyotypes of Alophia drummondii (2n = 14+1B, 28, 42 and 56), Cipura paludosa (2n = 14), C. xanthomelas (2n = 28) and Eleutherine bulbosa (2n = 12) were asymmetric; Neomarica candida, N. caerulea, N. humilis, N. glauca, N. gracilis, N. northiana and Neomarica sp. (2n = 18); N. cf. paradoxa (2n = 28), Trimezia fosteriana (2n = 52), T. martinicensis (2n = 54) and T. connata (2n = 82) were all generally symmetric. New diploid numbers of 2n = 56 for Alophia drummondii, 2n = 18 for N. candida, N. humilis, N. glauca, and N. gracilis, 2n = 28 for N. cf. paradoxa, and 2n = 82 for T. connata are reported. The karyotypic evolution of the studied species is discussed.  相似文献   

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Agroecosystems consist on complex trophic relationships among host plants, herbivores and their natural enemies. This article reviews the research of plant volatiles in Brazil, in order to determine multiple resistance mechanisms of economically important crops and to contribute to the understanding of insect-plant interactions. Most pest management programs, including chemical and biological control, do not consider the impact of these chemicals on herbivores and their natural enemies. Alternative control methods are being developed in order to improve our understanding on the endogenous mechanisms of plant induced defenses against phytophagous arthropods. The use of plant volatiles technology as an additional tool in integrated pest management programs would offer a new and environmentally sound approach to crop protection. This technique involves the development of baits that attract beneficial organisms and the manipulation of biochemical processes that induce and regulate plant defenses, key factors in the improvement of control programs against economically important pests. The elucidation of the mechanisms involved in the indirect defenses of plants will result in useful tools for biological control of crop pests.  相似文献   

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In the interior of northeastern Brazil there occurs the Santana Formation of Aptian age, composed lithologically of three members: Crato — an alternation of thin limestones and shales; Ipubi — gypsum; and Romualdo — almost pure limestone. The formation is very fossiliferous; pollen, plant remains, ostracodes, conchostracans, mollusks, echinoids, fishes and a few reptiles. The fishes and reptiles occur in limestone concretions. All data on sediment character and on fossils have been considered together for the interpretation of the palaeoenvironment of the formation.It was concluded that at the time of the Crato Member the deposition occurred in shallow lakes and swamps. Later (Ipubi Member), a marine invasion took place during a time of dry climate, causing anhydrite precipitation. Gradually the connection with the sea became obstructed so that the environment at the end of the depositional period became once more one of fresh water (Romualdo Member). Faunal assemblages and sediments point to a fairly great supply of river water during the whole time of basin deposition, under warm and dry climatic conditions. The connection with the sea persisted for a rather short period.  相似文献   

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Ismar Souza Carvalho 《Ichnos》2013,20(3-4):311-321
The Brazilian Cretaceous basins located at the northeastern region of Brazil present a wide distribution of dinosaur tracks and isolated footprints in many environmental settings: alluvial fans, braided and meandering fluvial floodplains, marginal lake borders and tidal flats. They are mainly theropod and sauropod footprints of Neocomian and Cenomanian ages that are found in Sousa, Uiraúna-Brejo das Freiras, Araripe, Cedro, Malhada Vermelha, Lima Campos and São Luís Basins. The vertebrate ichnofossils are important biogenic sedimentary structures, a picture of the interaction between dinosaur's behavior and the substrate nature, allowing the paleobiological analysis and inferences about the palaeoenvironments.  相似文献   

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Opencast mining causes severe environmental impacts by removing the vegetation cover and depleting the fauna. Reforestation methods using native species and diverse pre- and post-disturbance approaches aim to recover the original richness and diversity of species found before the impact. Bioindicators are powerful tools to evaluate the restoration of the original environmental conditions in disturbed areas. We used species richness, endemism and diversity measurements of Collembola to compare successional stages in reforested sites of different ages compared with a control undisturbed area. Richness and abundance of Collembola were subjected to correlation analysis with age of plots and vegetational variables. Areas that were reforested for up to 16 years supported a much lower Collembola species richness than undisturbed areas. Both the age of reforestation plots and vegetation variables (number of trees, diameter of crowns, depth of leaf litter and tree species richness) were positively and significantly correlated to collembolan abundance and richness. The results showed that the diversity of the 16-year-old plot was significantly higher than that of younger areas, but significantly less diverse than that of the control area. Endemic species were more sensitive to disturbance than non-endemics. Thus, species richness and diversity of soil Collembola can be only partially restored with appropriate reforestation methods, and although it takes many years, to some extent even endemic species can be gradually restored. Nevertheless, the maintenance of undisturbed diversity reservoirs linked by ecological corridors to reforested plots is imperative, as only undisturbed areas can support most of the endemic species able to re-colonize reforested sites.  相似文献   

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Invasive plants are a serious threat to biodiversity. Yet, in some cases, they may play an important ecological role in heavily modified landscapes, such as where fleshy‐fruited invasive plants support populations of native frugivores. How can such conservation conflicts be managed? We advocate an approach in which native fleshy‐fruited plants are ranked on their ability to provide the fruit food resources for native frugivores currently being provided by invasive plants. If these native taxa are preferentially used, where ecologically appropriate, in plantings for restoration and in park and garden settings, they could help support native frugivore populations in the event of extensive invasive plant control. We develop and critically examine six approaches to selecting candidate native plant taxa: a multivariate approach based on the frugivore assemblage, a scoring model, and several multivariate approaches (including trait combinations having the greatest correlation with the diet of the native frugivore assemblage) based on the functional traits of fruit morphology, phenology, conspicuousness, and accessibility. To illustrate these approaches, we use a case study with Bitou bush (Chrysanthemoides monilifera subsp. rotundata) (Asteraceae), an Australian Weed of National Significance. The model using a dissimilarity value generated from all available traits identified a set of species used by the frugivores of C. monilifera more than null models. A replacement approach using species ranked by either all traits available or the frugivore community appears best suited to guide selection of plants in restoration practice.  相似文献   

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The conical end of a plastic funnel can be sterilized and used for aseptic collection, transfer, and distribution of shaving samples drilled from a frozen-food product.  相似文献   

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Snakes are sold in many markets and religious article stores in Brazil. Besides their use as food, snakes are exploited in a variety of ways, such as pets, or for use in traditional medicine and magic/religious rituals (especially in Afro-Brazilian religions). Despite widespread commercialization, there is a general lack of information about this snake trade, which makes it difficult to evaluate its magnitude and its impact on reptile populations. This work documents the commercialization and use of snakes in five cities in Northeastern (São Luís, Teresina, João Pessoa and Campina Grande) and Northern (Belém) Brazil, through interviews with 119 merchants of biological products in outdoor markets and religious articles stores. The data was gathered through the use of semi-structured questionnaires, complemented by semi-directed interviews. The products derived from 11 snake species were being commercialized for medicinal or magical/religious purposes. Boa constrictor, Crotalus durissus and Eunectes murinus were the species most commonly sold. The economic importance of snakes as sources of medicines and religious products demonstrates the need for the development of sustainable use programs for these species.  相似文献   

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