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1.
Zootaxa ; 4629(4): zootaxa.4629.4.3, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31712500

RESUMO

Colomastigids are small, commensal marine amphipods distributed worldwide. Here we present descriptions of three new species of Colomastix Grube, 1861 from Todos-os-Santos Bay (Bahia state), and separately identification keys to males and females of all known Colomastix species from the Atlantic Ocean. Males of Colomastix iemanja sp. nov. can be distinguished from all others in the genus especially by the bifurcate apex of inner ramus of uropod 1, with highly asymmetric branches surrounded by a membranous-like structure. Males of Colomastix tubulosa sp. nov. can be distinguished from all others in the genus especially by the tube-like morphology of the apex of inner ramus of uropod 1, the morphology of the distalmost palmar process of gnathopod 2 and by the expanded inner ramus of uropod 2. Females of Colomastix iemanja sp. nov. and Colomastix tubulosa sp. nov. are the only species in the Atlantic with a pleated apex on dactylus of gnathopod 2, besides Colomastix trispinosa Silvany, Alves Senna, 2019. Colomastix marielle sp. nov. can be distinguished from all other species in the genus by the elongate carpus of pereopod 5 of females and by the rudder-like morphology of the apex of inner ramus of uropod 1 of males. These three new species increase the number of Colomastix in the Atlantic from 18 to 21, and are amongst the first records of the suborder Colomastigidea Lowry Myers, 2017 from Brazilian waters.


Assuntos
Anfípodes , Animais , Oceano Atlântico , Baías , Brasil , Feminino , Masculino
2.
Zootaxa ; 4587(1): zootaxa.4587.1.1, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31716113

RESUMO

33 species of shallow-water Demospongiae (Phylum Porifera) are described from Sodwana Bay, iSimangaliso Wetland Park, on the east coast of South Africa. Of the 33 species collected, 18 are redescribed from fresh material and 15 are new to science. Orders Clionaida, Poecilosclerida, Axinellida, Haplosclerida and Dictyoceratida are well represented in the collection with 4 to 6 species each, with the first three groups appearing to have the greatest diversity on the east coast of South Africa. The east coast of South Africa appears to have a high abundance of poecilosclerid and dictyoceratid sponges. The results of this study underscore the importance of poecilosclerid and dictyoceratid sponge fauna of the east coast of South Africa, in terms of the potential for the continued discovery of new species.


Assuntos
Poríferos , Áreas Alagadas , Animais , Baías , África do Sul , Água
3.
Zootaxa ; 4614(2): zootaxa.4614.2.7, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31716383

RESUMO

Two new species of the family Xyalidae from the Laizhou Bay of the Bohai Sea, China are described and illustrated herein. Daptonema papillifera sp. nov. is characterized by relatively small body size, L-shaped spicules with a large cephalate proximal end, triangular gubernaculum with a dorsal apophysis, 5-6 conjoint precloacal cuticularized spines and two ventral papillae located at the middle of the tail. Daptonema papillifera sp. nov. is easily distinguished from the other species in this genus by having 5-6 conjoint precloacal cuticularized spines and two ventral caudal papillae. Pseudosteineria anteramphida sp. nov. is characterized by eight groups of long subcephalic setae located posterior to amphideal fovea, curved slender spicules with cephalate proximal end and tapered distal end, tubular gubernaculum without apophysis, precloacal supplements absent, and a short precloacal seta present. In comparison with its most similar congeneric species, P. ventropapillata Tchesunov, 2000 the new species differs in having smaller body, not jointed cephalic setae, absence of precloacal supplements and absence of gubernacular apophysis.


Assuntos
Nematoides , Animais , Baías , Tamanho Corporal , China , Cromadoria
4.
Zootaxa ; 4576(2): zootaxa.4576.2.3, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-31715761

RESUMO

A new species of guitarfish, Rhinobatos ranongensis sp. nov., is described from 5 preserved specimens, and images and tissue samples of additional material, collected from the Andaman Sea and Bay of Bengal. This species co-occurs in the eastern sector of the northern Indian Ocean with two poorly defined congeners, R. annandalei Norman and R. lionotus Norman, which have been misidentified and confused with Indo-Pacific congeners since they were first described in 1926. Norman's species are rediagnosed based on limited new material and a re-examination of the types. In the western sector of the northern Indian Ocean, Rhinobatos annandalei has been confused in recent literature with the sympatric R. punctifer Compagno and Randall, which is represented by four primary colour morphs, including a white-spotted colour morph resembling R. annandalei. Rhinobatos punctifer also displays strong intraspecific variability and sexual dimorphism in some body dimensions. These four species of Rhinobatos have unique MtDna sequences and belong to a clade of Indo-West Pacific species that are morphologically similar. Despite the relatively small numbers of specimens available for investigation, these species exhibit some clear differences in body proportions, meristics and squamation. Rhinobatos ranongensis sp. nov. differs from its northern Indian Ocean congeners through a combination of a relatively narrow disc and mouth, high vertebral count, long snout, low dorsal fins, and being largely plain coloured. A new lectotype and a paralectotype are designated for the syntypes of R. annandalei, and the four primary colour forms of R. punctifer, the plain, white-spotted and ocellated morphs, are described and the three nominal species rediagnosed. A key is provided to the four known members of the genus in the northern Indian Ocean.


Assuntos
Raias , Animais , Baías , Oceano Índico , Oceano Pacífico
5.
Zootaxa ; 4576(2): zootaxa.4576.2.5, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-31715763

RESUMO

The deep-water sponge fauna of the Canadian Arctic remains to be fully described, particularly in areas that are not sampled by fisheries stock-assessment trawl surveys such as the major bays and fjords of the northern Labrador Sea and Baffin Bay. Frobisher Bay is a large inlet located on the southeast of Baffin Island. We used a remotely operated vehicle, as well as box cores and Agassiz trawls to study the sponge fauna of this bay. Over three years, from 2015 to 2017, sponge specimens were collected representing 24 distinct sponge taxa. Dense gardens of Iophon koltuni Morozov, Sabirov, Zimina, 2019 were discovered at a site near Hill Island in inner Frobisher Bay. The species has a unique finger-like growth form and provides complex habitat in the inner bay. Other sponge species are new to the Northern Labrador marine ecoregion. In particular, we report geographic range extensions of Tetilla sibirica (Fristedt, 1887) and Craniella polyura (Schmidt, 1870), and provide spicule measurements and descriptions of Iophon piceum (Vosmaer, 1882) and Mycale lingua (Bowerbank, 1866). These species identifications, geographic range extensions, and an expanded description of a species synonym represent the first inventory of the sponge fauna of Frobisher Bay.


Assuntos
Poríferos , Animais , Regiões Árticas , Baías , Canadá , Jardins , Terra Nova e Labrador
6.
Zootaxa ; 4567(2): zootaxa.4567.2.5, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715898

RESUMO

Here we report on the holothurian fauna at the Avilés Canyon System (Natura 2000 Site of Community Importance), central Cantabrian Sea, northern Spain. The samples were collected during several cruises covering the shelf, the continental slope and the abyssal depth. We identified 174 specimens, belonging to 35 species of the seven orders of class Holothuroidea. Depth was the main structuring agent. Multivariate analysis allowed the differentiation of four main assemblages which corresponded to abyssal plain, lower continental slope, upper continental slope, and continental shelf. Depth had a significant effect on holothurian species richness (it increased with depth at an approximate rate of 1.7 species 1000 m-1), which is consistent with previously described global patterns.


Assuntos
Equinodermos , Pepinos-do-Mar , Animais , Baías , Biodiversidade , Espanha
7.
Zootaxa ; 4674(1): zootaxa.4674.1.7, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31716024

RESUMO

A new species of the often-cryptic genus Polycheria (Crustacea; Amphipoda) was discovered living in a small specimen of the sponge, Homaxinella erecta (Brøndsted, 1924) (Demospongiae, Suberitida, Suberitidae), in Spirits Bay, on the northern tip of the North Island of New Zealand. Polycheria spongoteras sp. nov. is described using integrative techniques (morphologically, molecularly and ecologically), with discussions on the New Zealand records of the genus and related taxa. The host sponge is redescribed and placed in the Spirits Bay context. [Zooban URL: urn:lsid:zoobank.org:act:FB60B77B-6B98-4102-A41F-D980B03204EB].


Assuntos
Anfípodes , Poríferos , Animais , Baías , Nova Zelândia
8.
Zootaxa ; 4691(3): zootaxa.4691.3.4, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31719392

RESUMO

A new myzostome species, described here as Myzostoma khanhkhoaensis sp. nov., was collected in Nhatrang Bay, central Vietnam, during investigation of symbionts associated with crinoids. Myzostoma khanhkhoaensis sp. nov. was found only on Clarkcomanthus albinotus Rowe, Hoggett, Birtles Vail, 1986 in dense groups of up to 25 specimens. This species closely matches the colour pattern of the host by adjusting its cryptic colour and infects the distal part of crinoid arms, causing them to become curved. This is the first record of myzostomes that induce deformation of skeletal elements without the formation of galls or cysts. Morphologically M. khanhkhoaensis sp. nov. is close to M. cuniculus and M. pseudocuniculus but clearly differs from both of them by the shape of caudal blade and chaetae. Molecular-genetics analysis based on CO1, 16S and 18S DNA placed M. khanhkhoaensis sp. nov. in a clade including M. cuniculus, M. pseudocuniculus and M. indocuniculus.


Assuntos
Anelídeos , Baías , Animais , Equinodermos , Vietnã
9.
Zootaxa ; 4608(3): zootaxa.4608.3.4, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31717133

RESUMO

Two new and one known species of free-living marine nematode belonging to the family Phanodermatidae are described. They were collected during the 12th Japanese Association for Marine Biology (JAMBIO) Coastal Organism Joint Survey off Jogashima, Japan in Sagami Bay, North Pacific Ocean. Phanodermopsis kohtsukai sp. nov. differs from the congeners by the shape of the tail, the longer spicules, and the absence of the gubernaculum. Micoletzkyia nakanoi sp. nov. differs from the congeners by the absence of a circle of cervical setae, the proportion of the tail, the cylindrical gubernaculum without projection, and the position of the vulva. Crenopharynx caudata (Filipjev, 1927) comb. nov. is transferred from the genus Phanodermopsis based on the presence of the long spicules. The morphological characters of the newly collected specimens of C. caudata comb. nov. are in excellent agreement with those shown in the original description of the specimens from Arctic Russia and the previous redescription of the specimens from Skagerrak. The new diagnoses and species lists for these three genera and two dichotomous keys to the males of Micoletzkyia and Crenopharynx are provided.


Assuntos
Enoplídios , Nematoides , Animais , Baías , Feminino , Japão , Masculino , Oceano Pacífico , Federação Russa
10.
Zootaxa ; 4608(2): zootaxa.4608.2.2, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31717145

RESUMO

Four species of Mazocraeoides Price, 1936 including two new species are recorded from clupeiform fishes collected from Visakhapatnam Coast, Bay of Bengal: M. rotundus n. sp. from Ilisha filigera, M. fusiformes n. sp. from Stolephorus indicus, M. prashadi Chauhan, 1950 from Sardinella longiceps and M. dussumieri Mamaev, 1975 from Dussumieria hasselti. Mazocraeoides rotundus n. sp. is differentiated from the previously described species of Mazocraeoides by possessing the following combination of characters: the small pot-like body, the distribution of clamps in the posterior half of body and the genital complex consisting of five pairs of hooks arranged in two vertical rows. It differs from M. prashadi in the body shape and the much smaller size of the genital complex. Mazocraeoides fusiformes n. sp. differs from all the other species of the genus in the distribution of the clamps embracing only the posterior part of the testis and the genital complex consisting of one pair of needle-like lateral hooks and five pairs of median hooks. Mazocraeoides prashadi is redescribed to fill the gaps existing in the earlier description. Mazocraeoides dussumieri recorded earlier from South China Sea is reported for the first time from the Bay of Bengal. The validity of various species of Mazocraeoides is discussed and a key for the separation of valid species is provided. A host-parasite list is presented which gives details of the hosts, the geographic distribution and the validity status for each species. A partial 28S rDNA sequence was generated for M. dussumieri and deposited in GenBank.


Assuntos
Trematódeos , Animais , Baías , China , Peixes , Brânquias , Masculino
11.
Environ Sci Technol ; 53(22): 13417-13426, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31693343

RESUMO

Despite the increase in production, usage, and discharge of organophosphate flame retardants (OPFRs), little information is available about their bioaccumulation and trophic transfer in the marine food web. In this study, seawater, sediment, and marine species (10 fish and 9 invertebrate species) collected from Laizhou Bay, North China, were analyzed to investigate the levels, bioaccumulation, and biomagnification of OPFRs in a marine food web. Of 20 OPFRs screened for, 17 were quantifiable in seawater, sediment, and organisms. The ∑OPFRs concentrations ranged from 0.2 to 28.4 ng/L in seawater, 0.1-96.9 ng/g dry weight in sediment, and 21.1-3510 ng/g lipid weight in organisms. Benthic fish accumulated more OPFRs than pelagic fish and invertebrates. A linear and significant increase of bioaccumulation factors with increasing lipophilicity of OPFRs was observed (R2 = 0.63, p < 0.05), and the biota-sediment accumulation factors increased with hydrophobicity up to log KOW = 4.59 and then decreased with increase in log KOW. Trophic magnification factors of OPFRs ranged from 1.06 to 2.52, indicating biomagnification potential of OPFRs in a marine food web. This study provides important insight into the biomagnification potential of OPFRs and suggests further investigation on this group of chemicals.


Assuntos
Retardadores de Chama , Poluentes Químicos da Água , Animais , Baías , China , Monitoramento Ambiental , Peixes , Cadeia Alimentar , Organofosfatos
12.
J Environ Qual ; 48(5): 1191-1203, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31589735

RESUMO

Hennig Brandt's discovery of phosphorus (P) occurred during the early European colonization of the Chesapeake Bay region. Today, P, an essential nutrient on land and water alike, is one of the principal threats to the health of the bay. Despite widespread implementation of best management practices across the Chesapeake Bay watershed following the implementation in 2010 of a total maximum daily load (TMDL) to improve the health of the bay, P load reductions across the bay's 166,000-km watershed have been uneven, and dissolved P loads have increased in a number of the bay's tributaries. As the midpoint of the 15-yr TMDL process has now passed, some of the more stubborn sources of P must now be tackled. For nonpoint agricultural sources, strategies that not only address particulate P but also mitigate dissolved P losses are essential. Lingering concerns include legacy P stored in soils and reservoir sediments, mitigation of P in artificial drainage and stormwater from hotspots and converted farmland, manure management and animal heavy use areas, and critical source areas of P in agricultural landscapes. While opportunities exist to curtail transport of all forms of P, greater attention is required toward adapting P management to new hydrologic regimes and transport pathways imposed by climate change.


Assuntos
Baías , Fósforo , Agricultura , Hidrologia , Solo
13.
Environ Sci Technol ; 53(21): 12291-12299, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31633348

RESUMO

The United States Environmental Protection Agency has established aggressive nutrient reduction goals to achieve water quality objectives for the Chesapeake Bay estuary. Nitrogen (N) reduction goals are proving particularly difficult to meet with an additional 20.4 million kg of annual nitrogen reductions needed by 2025, and many of the easily achievable and low-cost N reductions have been realized. We assess the feasibility of employing woodchip denitrifying bioreactors to treat legacy N derived from spring discharge in the Mid-Atlantic region. We estimate that in excess of 6100 kg of soluble N is discharged daily from United States Geological Survey identified springs in four Mid-Atlantic states within the Chesapeake Bay watershed. Based on typical bioreactor removal efficiency (30-55%) and potentially treatable flows (<6000 m3/d), widespread adoption of bioreactors to treat legacy N from 231 springs could conservatively result in 420-770 kg N removed per day, while strategic adoption targeting 48 springs with N concentrations of at least 3 mg/L and flows of at least 500 m3/d could result in 322-590 kg N removed per day more cost-effectively and with far fewer installations. A cost analysis indicates bioreactors can be a cost-effective N removal strategy, generally removing N for less than $5/kg·y. Relative to other nonpoint source pollution control practices, bioreactors also offer the ability to remove larger quantities of N per installation and are more easily monitored to quantify N reductions.


Assuntos
Nitrogênio , Qualidade da Água , Baías , Reatores Biológicos , Estudos de Viabilidade , Metas , Mid-Atlantic Region
14.
Water Sci Technol ; 80(2): 274-281, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31537763

RESUMO

Connecting storm-sewers located at rather different elevations may be made with vortex drop shafts in which the energy dissipation is made by the friction between the vertical shaft and the flow and downstream by the impinging jet in a dissipation chamber. Following the first model design in the 1940s, different types of vortex drop shafts have been developed. One of the most used type is the so-called spiral vortex drop shaft developed to work in supercritical flow with good performance in both energy dissipation and space constrains. In this paper, an experimental flow characterization in a spiral vortex drop shaft is conducted covering the three main components of these structures, namely the inlet channel, the vertical shaft and the dissipation chamber. The results include measurement of water depths, pressure and velocity.


Assuntos
Drenagem Sanitária , Movimentos da Água , Baías , Pressão
15.
J Environ Manage ; 251: 109554, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541847

RESUMO

In this study, performance of biotrickling filters (BTFs) inoculated with fungus Phanerochaete chrysosporium at 30 °C and 40 °C in the absence and presence of silicone oil (10% v/v) was investigated. Removal of toluene was carried out at empty bed residence time (EBRT) of 1 min and at inlet concentrations of 0.5-4.4 g m-3 and 0.5-24.7 g m-3 for one-liquid phase (OLP-BTF) and two-liquid phase BTF (TLP-BTF), respectively. In general, at 40 °C, removal efficiencies (REs) > 80% were obtained in OLP-BTF for the inlet toluene concentrations < 2.5 g m-3, and REs > 70% were obtained for concentrations < 18 g m-3 in TLP-BTF. Based on the balanced equation for biodegradation, fungal respiration produced more CO2 in OLP-BTF (1.38 mol CO2/mole toluene) in comparison to TLP-BTF (0.67 mol CO2/mole toluene). In other words, the presence of oil enhanced microbial growth due to the increase of hydrophobic substrate bioavailability. The activity of extracellular ligninolytic manganese peroxidase (MnP) enzyme produced by the fungal culture was detected in the range of 27.6-71.6 U L-1 (µmol min-1 L-1) at 40 °C in TLP-BTF, while no enzymatic activity was detected in OLP-BTF.


Assuntos
Poluentes Atmosféricos , Tolueno , Baías , Biodegradação Ambiental , Reatores Biológicos , Filtração , Fungos , Peroxidase , Peroxidases , Temperatura Ambiente
16.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3233-3244, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529899

RESUMO

As the link among species, ecological environment, and ecosystem function, functional diversity can help us to better understand the relationship between biodiversity and ecosystem function. We analyzed functional diversity with thirteen functional traits reflecting the characteristics of food acquisition, locomotion, ecological adaptation, reproduction and population dynamics of fish species. The seasonal, interannual and spatial variations of functional diversity of fish communities were examined using functional richness index (FRic), functional evenness index (FEve), functional divergence index (FDiv) and community weighted mean index (CWM) based on the data from the bottom trawl surveys in spring and autumn from 2011 to 2017 (except 2012) in Haizhou Bay. The results showed that functional diversity indices were significantly different in spring and autumn, with FRic was significantly higher in autumn than that in spring and FDiv was significantly higher in spring than that in autumn. Migration might be the main reason for the seasonal change of functional diversity indices. CWM analysis showed that dominant fish species were cold-temperate or warm-temperate species, with higher trophic level, strong motion ability, and relatively high growth coefficient, resilience and vulnerability in spring. In autumn, the dominant species showed the opposite traits. In both spring and autumn, fish species with pelagic eggs dominated the fish communities. Inter-annual variations in functional diversity indices were observed in spring and autumn. The functional diversity indices showed an annual fluctuation during the study period in both spring and autumn, indicating the low stability of fish community in Haizhou Bay. Significant spatial changes in functional diversity of fish assemblages were observed, with FDiv being higher in the offshore coastal waters (>20 m) than that in the shallow waters (<20 m). The functional diversity showed obvious spatio-temporal variation. The ecological niches and resource utilization of fish species varied with season, year and space in Haizhou Bay.


Assuntos
Baías , Biodiversidade , Ecossistema , Peixes , Animais , Dinâmica Populacional
17.
Dis Aquat Organ ; 135(3): 211-226, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486413

RESUMO

These case reports describe locally invasive black pigmented mycotic infections of the skin and gills of saffron cod Eleginus gracilis associated with 8 different opportunistic ascomycete fungi: Alternaria sp., Cladosporium herbarum, Chaetomium globosum, Cadophora luteo-olivacea, Penicillium sp., Phoma herbarum, Pseudophacidium ledi and Valsa sordida. These fungi were isolated on conventional media, identified according to morphological structures and confirmed by genetic sequencing. Several of these fungi are primary plant pathogens as well as opportunistic human pathogens in immunocompromised individuals. Several have also been described as causing opportunistic infections of fish. This case material represents the first report of C. luteo-olivacea, C. globosum, P. ledi and V. sordida as likely opportunistic fish pathogens in Alaskan watersheds of Norton Sound and south in Toksook Bay and possibly elsewhere.


Assuntos
Ascomicetos , Crocus , Feoifomicose , Alaska , Animais , Baías , Humanos
18.
Ecotoxicol Environ Saf ; 183: 109477, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31369939

RESUMO

The increasing eutrophication of freshwater and brackish habitats globally has led to a corresponding increase in the occurrence of harmful cyanobacterial blooms. Cyanobacteria can produce highly toxic substances such as microcystins (MCs) that affect the health of livestock, wildlife, and humans. The present study broaden the understanding of cyanobacteria ecology and MC dynamics in the field, focusing on the estimation of the production and sedimentation rates of MCs in a natural habitat. The nutrient concentrations of the reservoir water and sediment pore water were monitored at 3-h intervals for 24 h during the summer cyanobacterial bloom. The DIN uptake rate of Microcystis in the Isahaya reservoir was estimated and the large-scale blooms in the reservoir were largely controlled by the interactions between rainfall and nutrient levels in the warm season. By using calculations based on the nitrogen budgets and tracking changes of the MC concentrations in the water column, the total MC production and sedimentation rates were estimated to be 52.2 kg MCs d-1 and 21.5 kg MCs d-1, respectively. Although MCs could be degraded in the environment, the MC sedimentation still comprised 41% of the in-water production.


Assuntos
Toxinas Bacterianas/análise , Baías/microbiologia , Toxinas Marinhas/análise , Microcistinas/análise , Toxinas Bacterianas/metabolismo , Baías/química , Ecossistema , Eutrofização , Sedimentos Geológicos/química , Japão , Toxinas Marinhas/metabolismo , Microcistinas/metabolismo , Microcystis/metabolismo , Nitrogênio/metabolismo , Nutrientes , Estações do Ano
19.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2829-2836, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418209

RESUMO

Based on the bottom trawl surveys in spring (May) and in autumn (September to October) from 2011 to 2017 (except 2012) in Haizhou Bay, variations in the mean trophic levels (MTL) and large fish index (LFI) of fish community were examined to understand the changes of fish community structure in Haizhou Bay. The results showed that the dominant fish species were Hexagrammos otakii, Enedrias fangi, Syngnathus acus, Pseudosciaena polyactis and Saurida elongata, which had obvious seasonal variation. The mean trophic level of fish community varied significantly among different years and seasons. Generally, MTL in autumn was higher than that in spring, and the variation of which in autumn always lagged behind that in spring. The result of LFI calculation showed that the large fish resources declined and fish community structure in Haizhou Bay showed an obvious tendency of miniaturization in recent years.


Assuntos
Baías , Peixes/fisiologia , Animais , China , Peixes/classificação , Perciformes , Estações do Ano
20.
Environ Monit Assess ; 191(9): 554, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399761

RESUMO

A proper evaluation and performance assessment of climate model projections have received considerable attention during the recent past amongst the scientific community. Quality of wind datasets used for analysis is of paramount importance to meteorologists, oceanographers, and climatologist as an essential pre-requisite for modelling needs. This study examined the measured wind speeds obtained from satellite altimetry available from IFREMER/CERSAT, along with two atmospheric reanalysis products ECMWF ERA-Interim and NCEP-CFSR. The reanalysis products and altimeter data were compared with wind speed simulated from 33 different models under WCRP-CMIP5 project for the Bay of Bengal (BoB) region. Study investigated both historical and projections of CMIP5 data providing an opportunity to inter-compare the wind speeds resulting from various emission scenarios with Representative Concentration Pathways (RCPs) 2.6, 4.5, 6.0, and 8.5, respectively. The objective is to establish and find out a suitable emission scenario applicable to the BoB region. Temporal and spatial analyses of CMIP5 data infer variability in terms of correlation, bias, and root mean square error. For the historical runs (1991-2005) based on analysis of 29 CMIP5 models, it could be ascertained that the correlation coefficient in wind speed varied between 0.6 and 0.9 and with a bias ranging from - 1.6 to 4 ms-1. Similar analysis of the CMIP5 projections was carried out with 11 models for RCP 2.6, 29 models for RCP 4.5, 10 models for RCP 6.0, and 28 models for RCP 8.5. Basin-scale mean using altimeter and re-analysis products indicates that RCPs 2.6 and 6.0 showed less correlation with a higher bias for the study region. Analysis of historical model runs signifies that HadGEM2-ES, HadGEM2-AO, HadGEM2-CC, MIROC5, GISS-E2R, and CNRM-CM5 are the best performing models for the study domain. Findings from the study indicate that RCP 4.5 wind speed stands better for the Bay of Bengal region. In a broader perspective, due to various uncertainties involved in climate model outputs, it is imperative to perform a comprehensive analysis amongst multiple data sources to establish and identify the best quality data for scientific needs.


Assuntos
Mudança Climática/estatística & dados numéricos , Monitoramento Ambiental/métodos , Vento , Baías , Clima , Previsões , Análise Espacial
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