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231.
Alyssa B. Novak Ellen Hines Donna Kwan Leslee Parr Mya Than Tun Han Win Frederick T. Short 《Aquatic Botany》2009,91(3):250-252
In a survey of the Myeik Archipelago, we documented seven seagrass species in the southern region. Three seagrass species (Cymodocea rotundata, Enhalus acoroides, and Halophila ovalis) have previously been reported in the Myeik Archipelago; three species (Halodule pinifolia, Halodule uninervis, Syringodium isoetifolium) are new reports for the archipelago; and one species (Thalassia hemprichii) is a new report for Myanmar. 相似文献
232.
Kannan Karuppiah Kannapiran Ethiraj Kodeeswaran Paramasivam Kumar Rajendran Madhuri Krishnamoorthy Divya Dharmaraj 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):860-862
This study deals with the length-weight relationships (LWRs) of three commercially important marine fishes belonging to the family Clupeidae from the major landing centers in Tuticorin, Mandapam, Thondi, Nagapattinam and Chennai in southeast coast of India. Monthly sampling were done at the respected landing centers from June, 2018 to April, 2019 from the commercial trawlers (with cod-end mesh size of 25–35 mm) and gill netters (with different mesh size vary from 20 to 170 mm). The estimated ‘b’ values ranged from 3.1215 (Sardinella albella) to 3.1819 (Amblygaster clupeoides) and ‘a’ values varied from 0.0059 (A. clupeoides) to 0.0074 (S. albella). The study also provides a new maximum total length (TLmax) for two species A. clupeoides and Sardinella fimbriata. 相似文献
233.
Patricio Hernáez Amanda M. Windsor Caio Augusto Paula William Santana 《Marine Biology Research》2020,16(1):50-60
ABSTRACTA new species of ghost shrimp, Neocallichirus pinheiroi, is described based on specimens collected in subtidal habitats of Saquaira beach, northeastern coast of Brazil. This new species resembles N. lemaitrei Manning, 1993, but differs from it primarily in having a third maxilliped propodus expanded ventrally, and in the case of males, a large subtriangular tooth on the cutting edge of the major cheliped dactylus. Diagnostic features of the new species include: (i) frontal margin of carapace with rounded lateral projections not exceeding rostrum distal margin, (ii) third maxilliped carpus with row of sclerotized setae on median internal surface, (iii) minor cheliped with cutting edge of dactylus microscopically pectinate, (iv) endopod of male second pleopod with appendices interna and masculina. This is the seventh described species of the genus Neocallichirus from the western Atlantic and the fourth report of this genus in Brazil. A key for identification of western Atlantic species belonging to the genus is provided. 相似文献
234.
In order to obtain a better understanding on the relationship between salt and fresh-water masses in an estuary on the Northern Brittany coast, a study on the tidal dynamics has been carried out. A simple model for the calculation of the mean current velocities is proposed taking into account the estuarine topography, tidal parameters and river discharge. The model also estimates the Richardson, Froude and Reynolds estuarine numbers. These can be used in further studies on the particle transport in this estuary. 相似文献
235.
W. Wayne Price 《Hydrobiologia》1982,93(1-2):9-21
An illustrated key is presented for the shallow water mysid shrimp of the Texas coast. Six genera and 10 species are included. Information concerning the distribution, ecology, reproductive biology, and morphology of the species in Texas waters is given. 相似文献
236.
Masahiro Nakaoka Norihiko Ito Tomoko Yamamoto Takehiro Okuda Takashi Noda 《Ecological Research》2006,21(3):425-435
Factors and processes affecting community structures operate at various spatial and temporal scales. We analyzed how similarities
of rocky intertidal assemblages vary at different spatial scales using a nested, hierarchical sampling design. Intertidal
assemblages consisting of algae, sessile animals, and mobile animals were censused on five rock walls at each of five shores
chosen within each of six regions along the Pacific coast of Japan, encompassing 1,800 km of coastlines. Based on this sampling
design, similarities in assemblages were calculated using both qualitative (presence/absence) and quantitative (percent cover
and density) data, and compared at three spatial levels: (1) rock level (the finest spatial scale, encompassing several to
hundreds of meters), (2) shore level (the intermediate spatial scale, encompassing several to tens of kilometers), and (3)
region level (the broadest spatial scale, encompassing hundreds to thousands of kilometers). Cluster analysis showed that
assemblages were categorized into distinct regional groups except for the two southern regions, but they did not separate
clearly from each shore. A nested analysis of similarities revealed significant variation in similarities among regions and
among shores within each region, with the former showing greater variation. Similarity was negatively correlated with geographic
distance at the regional level but not at the shore or the rock levels. At the regional level, similarity decreased more rapidly
with distance for mobile animals than sessile organisms. The analyses highlighted the importance of broad-scale abiotic/biotic
factors such as oceanic current conditions and biogeographic factors in determining observed patterns in similarity of rocky
intertidal assemblages. 相似文献
237.
《Saudi Journal of Biological Sciences》2023,30(2):103540
IntroductionAmong other aquatic animals, fish can also accumulate a large number of toxic metals in their various body organs, which may enter in the human body and cause serious health issues. Therefore, the basic aim of this study was to observe the level of some heavy metals (i.e., Pb, Fe, Cu, Cd, Cr) found in the different tissues of Decapterus macarellus collected from the Karachi and Gwadar coasts of Pakistan.MethodsAbout 200 fish samples of five different size groups of Decapterus macarellus were collected from Gwadar and Karachi fish harbors during April to September 2020. Total 10 samples of each size group i.e., S1, S2, S3, S4 & S5 were collected from each coast. Heavy metals were analyzed in fish samples by using the atomic absorption spectrophotometer (AAS).ResultsThe overall results revealed that some metals like Cu, Pb, Cd & Cr contents were high in the stomach, while less in the muscles. Whereas, the concentration of Fe was found to be high in the liver, while low in skin of fish. The average values of bioaccumulation of these heavy metals (BAF) were found in decreasing order of Cu > Cd > Fe > Cr > Pb. In this study, except Cd and Cr, all metals were found within the permissible limits. Both sediment and water from the selected site areas were also analyzed to observe their pollution levels in the order of; sediment > water > fish tissues.ConclusionThus, it was concluded that the Karachi environment was much more polluted than the Gwadar environment because it is in an industrial unit and a busy sea site for trade. Moreover, consuming muscles from this species is safe for human health except for iron toxicity, but the use of the liver is not beneficial for all selected metals. Thus, the present work will also be helpful to monitor these toxic metals in a food chain and maintain a healthy life, and reduce all kinds of health risks associated with them. 相似文献
238.
The Godavari estuarine system extending over approximately316 km2 has significant annual variation of salinity dueto seasonal flooding which is mainly monsoon fed. This areahas dense vegetation of mangroves and is characterised bypredominance of Avicennia sp. Excoecaria agallochaand Rhizophora sp. In the coastal waters adjacent to themangroves three economically important species of prawns occur(Penaeus monodon, P. indicus and Metapenaeusmonoceros). Their larvae migrate and dwell in the mangroveenvironment. By analysis for the natural stable carbon isotoperatios, it was possible to establish the primary carbon sourcefrom the mangroves to that of larvae and juveniles of P. indicus and P. monodon. This information can be usedto exploit the mangrove habitat as prawnnurseries. 相似文献