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1.
Zootaxa ; 4809(3): zootaxa.4809.3.6, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-33055926

RESUMO

Two distinct morphotypes of sand bubbler crab (Dotillidae) from eastern India were assigned to Dotilla intermedia De Man, 1888, by British carcinologist, Stanley Kemp in 1919, due to similarities in the areolation of the carapace and the occurrence of these two forms in the same locality. Kemp, however, also illustrated the differences in the morphology of the male thoracic sternums, chelae, and first gonopods and, accordingly, divided D. intermedia into two subcategories which he called the "high form" and the "low form". The recent designation of a lectotype for D. intermedia, which corresponds with Kemp's "high form", makes it possible to recognize the "low form" as a distinct and new species, D. fraternalis n. sp., which is described here. Furthermore, Kemp's synonymization of Dotilla clepsydrodactylus Alcock, 1900, under Dotilla intermedia is affirmed here after examination of the surviving syntypes. A lectotype is selected to stabilize the taxonomy of this species.


Assuntos
Braquiúros , Animais , Baías , Índia , Masculino
2.
Zootaxa ; 4808(1): zootaxa.4808.1.1, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33055987

RESUMO

The Mexican Pacific has been the focus of several research expeditions, with 90 species of hydromedusae and more than 200 species of hydroids recorded for the region. However, only a few of these reports include taxonomic descriptions, hindering inferences of the phylogenetic relationships, species boundaries, and diversity of Hydrozoa in Mexican waters. In this study, we present detailed and illustrated descriptions of new records of hydromedusae and hydroids for La Paz Bay, Gulf of California. We found a total of 16 species comprising 15 genera, with three new records for the Gulf of California (polyps of Antennella secundaria, Bimeria vestita, and Ventromma halecioides), two new records for the Mexican Pacific (medusa of Clytia linearis, polyp of Halopteris violae), and we redescribe Obelia tenuis. We show that the diversity of Hydrozoa in the Mexican Pacific is likely underestimated, and we emphasize the importance of taxonomic and systematic studies of hydroids and hydromedusae in Mexico.


Assuntos
Hidrozoários , Animais , Baías , California , Filogenia
3.
Zootaxa ; 4780(3): zootaxa.4780.3.5, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33056514

RESUMO

Differentiation of species within the genus Dysidea Johnston, 1842 (Order Dictyoceratida Minchin, 1900, Family Dysideidae Gray, 1867) is extremely difficult as they lack spicules which are strongly diagnostic in other Demospongiae, and their primary and secondary fibres and the mesh that they form, may be irregular in shape and thickness, thus difficult to measure for comparisons. Here we review species of Dysidea known from the New Zealand Exclusive Economic Zone (EEZ), validating five species: Dysidea cristagalli Bergquist, 1961a, from the Hauraki Gulf; D. hirciniformis (Carter, 1885a) sensu Dendy (1924), from North Cape; D. navicularis Lendenfeld, 1888, from Port Lyttleton on the east coast of the South Island; D. ramsayi (Lendenfeld, 1888) from the Chatham Islands; D. spiculivora Dendy, 1924, from Cape Maria Van Diemen and the Three Kings Islands to the north of New Zealand. Dysidea fragilis (Montagu, 1818) sensu Bergquist (1961b), from Mernoo Bank on Chatham Rise, is now considered to be invalid, and D. elegans (Nardo, 1847) sensu Brøndsted (1927), from the Coromandel Peninsula, is considered unrecognisable. Several partially characterised species have also been cited in the literature. Two new species from Tauranga Harbour, on the northeast coast of the North Island, Dysidea tuapokere sp. nov. and D. teawanui sp. nov., are described. These descriptions are based on fresh material and in situ photography, facilitating clear, informative descriptions, that will enable ease of identification of these species in the future.


Assuntos
Dysidea , Poríferos , Animais , Baías , Nova Zelândia
4.
J Environ Qual ; 49(4): 812-834, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33016477

RESUMO

Despite decades of effort toward reducing nitrogen and phosphorus flux to Chesapeake Bay, water-quality and ecological responses in surface waters have been mixed. Recent research, however, provides useful insight into multiple factors complicating the understanding of nutrient trends in bay tributaries, which we review in this paper, as we approach a 2025 total maximum daily load (TMDL) management deadline. Improvements in water quality in many streams are attributable to management actions that reduced point sources and atmospheric nitrogen deposition and to changes in climate. Nutrient reductions expected from management actions, however, have not been fully realized in watershed streams. Nitrogen from urban nonpoint sources has declined, although water-quality responses to urbanization in individual streams vary depending on predevelopment land use. Evolving agriculture, the largest watershed source of nutrients, has likely contributed to local nutrient trends but has not affected substantial changes in flux to the bay. Changing average nitrogen yields from farmland underlain by carbonate rocks, however, may suggest future trends in other areas under similar management, climatic, or other influences, although drivers of these changes remain unclear. Regardless of upstream trends, phosphorus flux to the bay from its largest tributary has increased due to sediment infill in the Conowingo Reservoir. In general, recent research emphasizes the utility of input reductions over attempts to manage nutrient fate and transport at limiting nutrients in surface waters. Ongoing research opportunities include evaluating effects of climate change and conservation practices over time and space and developing tools to disentangle and evaluate multiple influences on regional water quality.


Assuntos
Baías , Fósforo/análise , Nitrogênio/análise , Nutrientes , Qualidade da Água
5.
Chemosphere ; 258: 127413, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947681

RESUMO

Fishing is part of the traditional activities of Indigenous people in Canada. However, it is also a route of exposure to methylmercury, a known neurotoxicant, and this is a concern for those who rely on fish as part of their diet. The probable weekly intake (PWI) of methylmercury from six species of fish was calculated for Indigenous community members (N = 1406), grouped by age and sex, and compared to Canadian and international provisional reference doses to assess exposure. Mixed-effects regression models were also used to estimate the input of methylmercury into the blood, and Hazard Quotients (HQ) were used to assess potential effects. Of the species of fish in our study, walleye and lake trout contributed the most to methylmercury intake. There was a positive association between the consumption of walleye and the total blood mercury concentrations of mercury in women and men (R2A = 0.40 and 0.47, respectively), and to a lesser extent, children. Similar results were observed for the consumption of lake trout. The 95th-percentile HQ for girls (3.16) and boys (3.18) from the consumption of lake trout was relatively high, and to a lesser extent, so was the HQ for walleye and pike. The consumption of some species of fish increases the exposure to methylmercury, however, taking a balanced approach, there are health benefits associated with the consumption of fish that must be considered. To mitigate future exposure to methylmercury, we recommend follow-up blood monitoring and local-geospatial-based assessments.


Assuntos
Exposição Dietética/estatística & dados numéricos , Monitoramento Ambiental , Compostos de Metilmercúrio/toxicidade , Poluentes Químicos da Água/toxicidade , Adolescente , Animais , Baías , Canadá , Criança , Dieta , Exposição Ambiental/análise , Feminino , Peixes , Humanos , Masculino , Mercúrio/análise , Compostos de Metilmercúrio/análise , Compostos de Metilmercúrio/metabolismo , Quebeque , Alimentos Marinhos/estatística & dados numéricos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo
6.
Mar Environ Res ; 160: 104980, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907718

RESUMO

While the effects of industrial contamination in coastal areas may persist for years in benthos communities, plankton should not show permanent impairments because of their high spatial dynamics, fast turnover times and pronounced seasonality. To test this hypothesis, in 2019 we conducted five surveys in the Bay of Pozzuoli (Gulf of Naples, Mediterranean Sea), in front of a dismissed steel factory and in the adjacent inshore coastal waters. High seasonal variability was observed for bacteria, phytoplankton and mesozooplankton, whereas plankton spatial gradients were relatively smooth during each survey. Plankton biomass and diversity did not reveal any effects of past industrial activities not even at the innermost stations of the Bay, which however showed some signals of present anthropogenic pressure. Hydrodynamic and morphological features likely play a prominent role in maintaining a relatively good status of the plankton of the Bay, which hints at the relevance of coastal circulation and meteorological dynamics to revitalize areas impacted by human activities.


Assuntos
Baías , Fitoplâncton , Plâncton , Biomassa , Mar Mediterrâneo
7.
Mar Environ Res ; 160: 105040, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907739

RESUMO

Chemical contamination of marine ecosystems represents a major concern for the detrimental consequences at different levels of biological organization. However, the impact of chronic contamination on the diversity and assemblage composition of benthic prokaryotes is still largely unknown, and this limits our understanding of the potential implications on ecosystem functioning. The Bagnoli-Coroglio bay (Gulf of Naples, Tyrrhenian Sea) is a typical example of coastal area heavily contaminated by metals and hydrocarbons, released for decades by industrial activities, which ceased at the beginning of nineties. In the present study we analyzed the abundance, diversity and assemblage composition of benthic prokaryotic assemblages at increasing distance from the historical source of contamination in relation to the heavy hydrocarbons (C > 12), polycyclic aromatic hydrocarbons (PAHs) and heavy metal concentrations in the sediments. Prokaryotic abundance in the sediments differed among sites, and was mostly driven by environmental factors rather than by contamination levels. Conversely, the richness of prokaryotic taxa was relatively high in all samples, was driven by contamination levels and decreased significantly with increasing contamination (15-38%). Moreover, our results indicate large variations in the composition of the benthic prokaryotic assemblages among sites, mostly explained by the different levels and types of chemical contaminants found in the sediments. Overall, our findings suggest that chemical contaminants, even after decades from the end of their release, can profoundly influence the richness and turnover diversity of the benthic prokaryotic assemblages, in turn promoting a high diversification of the benthic bacterial and archaeal assemblages by selecting those lineages more adapted to specific mixtures of different contaminants. Our results open new perspectives for understanding of the long-term effects of chemical contamination on the benthic prokaryotic assemblages and the ecological processes they mediate.


Assuntos
Sedimentos Geológicos , Metais Pesados , Poluentes da Água , Baías , Ecossistema , Células Procarióticas , Poluentes da Água/toxicidade
8.
Sci Total Environ ; 740: 140042, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927538

RESUMO

There is increasing interest in understanding potential impacts of complex pollutant profiles to long-lived species such as the green sea turtle (Chelonia mydas), a threatened megaherbivore resident in north Australia. Dietary ingestion may be a key exposure route for metals in these animals and marine plants can accumulate metals at higher concentrations than the surrounding environment. We investigated concentrations of 19 metals and metalloids in C. mydas forage samples collected from a group of offshore coral cays and two coastal bays over a period of 2-3 years. Although no samples exceeded sediment quality guidelines, coastal forage Co, Fe, and V concentrations were up to 2-fold higher, and offshore forage Sr concentrations were ~3-fold higher, than global seagrass means. Principal Component Analysis differentiated coastal bay from coral cay forage according to patterns consistent with underlying terrigenous-type or marine carbonate-type sediment geochemistry, such that coastal bay forage was higher in Fe, Co, Mn, Cu, and Mo (and others) but forage from coral cays was higher in Sr and U. Forage from the two coastal bays was differentiated according to temporal variation in metal profiles, which may be associated with a more episodic sediment disturbance regime in one of the bays. For all study locations, some forage metal concentrations were higher than previously reported in the global literature. Our results suggest that forage metal profiles may be influenced by the presence of some metals in insoluble forms or bound to ultra-fine sediment particles adhered to forage surfaces. Metal concentrations in Great Barrier Reef forage may be present at levels higher than expected from the global seagrass literature and appear strongly influenced by underlying sediment geochemistry.


Assuntos
Antozoários , Metais Pesados/análise , Tartarugas , Poluentes Químicos da Água/análise , Animais , Austrália , Baías , Monitoramento Ambiental , Sedimentos Geológicos
9.
Environ Monit Assess ; 192(10): 658, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32974766

RESUMO

Batan Bay in Aklan, Philippines supports a population largely dependent on coastal fisheries. The development of aquaculture technologies coupled with over-crowded fish pens has negatively affected its natural dynamics and environmental quality. Land-use activities including ports and shipyard further aggravate the problem by contributing to chemical pollution. The present study applied sequential extraction techniques to determine the geochemical speciation of metals in fishpond sediments. Samples were processed and analyzed for Cu, Cd, and Pb using flame atomic absorption spectroscopy. Copper (Cu) showed the highest concentration (10.61-66.81 µg/g-dry weight of sediment). Lead (Pb) content ranged from below detection limit to 15.14 µg/g, while Cd concentration ranged from below detection limit to 2.50 µg/g. Fractionation study showed that the Cu present in the fishpond sediments is mostly non-residual (50.03-73.34%) and significantly associated with the oxidizable fraction (33.89-64.75%). In contrast, the residual fraction served as the dominant host of Pb (33.55-62.68%) in the sediments. Comparison of the results with US EPA and NOAA sediment quality guidelines also revealed that the Batan Bay sediments may be considered generally non-polluted with respect Cu, Pb, and Cd, and not expected to cause adverse effects to aquatic organisms under normal conditions. However, under certain redox conditions, most of the sites may be considered moderately polluted as a result of Cu mobilization from the non-residual fractions of the sediments. Overall, geochemical speciation studies in an important fishery area like Batan Bay will provide valuable insights into the availability of metal contaminants to aquatic organisms under certain environmental conditions.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Baías , Cádmio , Monitoramento Ambiental , Sedimentos Geológicos , Chumbo , Filipinas
10.
Mar Pollut Bull ; 159: 111499, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32745747

RESUMO

Intertidal sediment samples from Shilaoren Bay, Qingdao, China, were collected to determine the concentrations and compositions of 16 polycyclic aromatic hydrocarbons (PAHs). The sources of PAHs were analyzed, and risk assessment was performed. Results show that the pollution level of PAHs in the investigated area was low. The majority of PAHs are four-ring PAHs. The PAHs in this region were mainly derived from combustion sources, including the incomplete combustion of petroleum, coal, and biomass, such as vegetation, which were affected to some extent by petroleum sources. The highest concentration of PAHs in all sampling sites was lower than that of effects range low, and the mean effects range median quotient was low. Therefore, the PAHs in the study area did not have toxic and side effects on the ecological environment, and ecological risk was low.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Baías , China , Monitoramento Ambiental , Sedimentos Geológicos , Medição de Risco
11.
Mar Pollut Bull ; 159: 111477, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32750595

RESUMO

Stable isotopic composition of carbon (δ13CPOM) and nitrogen (δ15NPOM) in the particulate organic matter (POM) is used to identify sources of organic carbon and nutrients using monthly time-series observation in the coastal Bay of Bengal (BoB). The hydrographic structure indicates that the coastal BoB is influenced by coastal upwelling during March-May, advection of peninsular river discharge during June to September and glacial (Ganges) river discharge during October to December due to reversing of East India Coastal Currents (EICC). C/N ratios in POM were mostly higher values than Redfield ratio in the study region indicating possible contribution of terrestrial origin. Enriched δ13CPOM were found during March-May associated with coastal upwelling indicating major contribution of POM from the in situ production while lower values were noticed during June to September followed by October to December indicating influence of terrestrial sources. δ15NPOM displayed strong inverse relation with salinity and linear relation with Chl-a suggesting that anthropogenic nutrients from the land increased coastal phytoplankton biomass. δ15NPOM linearly decreased with increase in distance from the coast and reached to the typical offshore value of 6-6.5‰ indicating that terrestrial nutrients influence was spread up to a distance of 15 to 20 km from the coast in the study region. Our study suggested that coastal waters are influenced by terrestrial/anthropogenic nutrients and its impact can be noticed up to 15 to 20 km from the coast and its impact on Biodiversity Beyond National Jurisdiction may be negligible than hitherto hypothesized.


Assuntos
Baías , Monitoramento Ambiental , Isótopos de Nitrogênio/análise , Nutrientes , Rios
12.
Mar Pollut Bull ; 159: 111536, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32771663

RESUMO

This paper reported the distribution of phytoplankton biomarkers in surface sediments of Liaodong Bay, Bohai Sea. The primary productivity indicated by biomarkers is consistent with the results from modern water column phytoplankton surveys, indicating that the biomarkers can be used to reconstruct the primary productivity. The productivity in the bay mouth is higher than in the shallow coast area, indicating that the main controlling factor is the turbidity rather than terrestrial nutrients. The high primary productivity near Juhua Island is mainly related to eutrophication caused by human culture and land-based sewage discharge. The relative proportion of biomarkers showed that diatom and dinoflagellate contributed more to the coastal area and were mainly related to the competitive advantage under the condition of high nutrient salts, while a high proportion of haptophytes was found in the middle, which corresponded to the high salinity water.


Assuntos
Diatomáceas , Fitoplâncton , Baías , Biomarcadores , China , Eutrofização , Humanos , Água do Mar
13.
Mar Pollut Bull ; 158: 111418, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32753202

RESUMO

In this study, the recent history of heavy metal pollution in the Fangcheng Bay (South China) was reconstructed utilizing three 210Pb-dated sediment cores. The metal concentration profiles display three trends since the 1970s and clearly reflect local urbanization and industrialization. The metals in the Fangcheng Bay started to accumulate in the 1970s but remained relatively low until the 1990s which corresponds to the slow urbanization and industrialization. The metal accumulation in the eastern Fangcheng Bay peaked in the early 2000s following the steep increases in accordance with the rapid industrialization of the eastern Fangcheng Bay where the core HSL was collected. Conversely, the heavy metal profiles in the western Fangcheng Bay present slight step increases in the early 2000s followed by a dramatic metal enrichment in the late 2000s; the expansion of these two cores, which begins in the early 2000s, concurs well with the rapid local urbanization and industrialization.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Baías , China , Monitoramento Ambiental , Sedimentos Geológicos , Desenvolvimento Industrial , Urbanização
14.
Mar Pollut Bull ; 158: 111449, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32753225

RESUMO

The ecological quality status of the NE region of the Guanabara Bay (SE Brazil), one of the most important Brazilian embayments, is evaluated. For this purpose, sediment samples from in the inner of the Guanabara Bay (GB) were collected and analyzed (grain-size, mineralogy, geochemistry and living foraminifera). In this study, it is hypothesized that the potentially toxic elements (PTEs) concentrations, in solution and associated with organic matter (OMPTEs, potential nutrient source), may represent two potential pathways to impact benthic foraminifers. A multiproxy approach applied to complex statistical analyses and ecological indexes shows that the study area is, in general, eutrophic (with high organic matter and low oxygen content), polluted by PTEs and oil. As a consequence, foraminifera are not abundant and their assemblages are poorly diversified and dominated by some stress-tolerant species (i.e., Ammonia tepida, Quinqueloculina seminula, Cribroelphidium excavatum). The results allow us to identify a set of species sensitive to eutrophication and OMPTEs. Factors such as the increase of organic matter contents and OMPTEs and, in particular of Zn, Cd and Pb, the oxygen depletion and the presence of oil, altogether contribute to a marked reduction in the abundance and diversity of foraminifera. Ammonia-Elphidium Index and the Foram Stress Index confirm that the NE zone of GB is, in general, "heavily polluted", with "poor ecological quality status" and experiences suboxic to anoxic conditions. In light of it, special attention from public authorities and policymakers is required in order to take immediate actions to enable its environmental recovery.


Assuntos
Foraminíferos , Baías , Brasil , Monitoramento Ambiental , Sedimentos Geológicos
15.
Sci Total Environ ; 738: 140346, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32806370

RESUMO

The present study was conducted during a time of drought to assess the concentration of herbicides and their potential for accumulation in marine biota found in the near shore marine environment of an urban setting (Camps Bay, Cape Town, South Africa). The purpose was to establish whether raw sewage containing selected persistent chemicals that are released through a local marine outfall would be sufficiently diluted by the ocean to prevent impact on the near-shore marine environment of the suburb Camps Bay. Samples of seawater, sediment, seaweed, and selected marine organisms present in the near shore environment, such as limpets (Cymbula granatina), mussels (Mytilus galloprovincialis), and sea urchins (Parechinus angulosus), were analysed for five indicator herbicides, namely atrazine, alachlor, simazine, metolachlor, and butachlor, with gas chromatography coupled with a mass spectrometer. The concentration of the compounds detected ranged from below the limit of detection (

Assuntos
Herbicidas/análise , Poluentes Químicos da Água/análise , Animais , Baías , Cidades , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Medição de Risco , África do Sul , Estados Unidos
16.
Ecotoxicol Environ Saf ; 204: 111067, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32745786

RESUMO

The impacts of microplastics (MPs) and phthalates (PAEs), a class of MP-associated contaminants, on the marine environment are not thoroughly understood despite concern over their adverse effects on humans and ecosystems. Field studies linking MPs and PAEs in seawater have not yet been reported. We investigate for the first time the correlation between MPs contamination and the presence of PAEs in the surface seawater of Jiaozhou Bay (JZB), a semi-enclosed metropolitan bay in northern China heavily impacted by human activity. The abundance of MPs, dominated by polyethylene and polyethylene terephthalate mostly smaller than 2 mm, ranged between 24.44 items/m3 and 180.23 items/m3, with the majority being black and transparent fibers and fragments. Concentrations of PAEs varied from 129.96 ng/L to 921.22 ng/L. Relatively higher abundances of MPs and higher concentrations of PAEs were generally found in areas near riverine inputs and sewage treatment plants. There was a strong correlation between PAEs concentration and MPs abundance, suggesting that they are closely linked. In a risk assessment combining PAEs and MPs, the risk quotients (RQs) indicated that the ecological risk of di-n-butyl phthalate in JZB was relatively high (0.046

Assuntos
Baías/química , Monitoramento Ambiental/métodos , Microplásticos/análise , Ácidos Ftálicos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , China , Dibutilftalato/análise , Ecossistema , Humanos , Polietileno/análise
17.
Sci Total Environ ; 745: 140993, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32758740

RESUMO

A long-term dataset, including physicochemical, nutrient, and phytoplankton assemblages from 1994 to 2016, was analyzed to investigate the response of the algal community to variations in environmental factors in Deep Bay and Mirs Bay in southern China. These bays differ in their overall nutrient loadings, as well as in physical factors. The results showed that diatoms were numerically dominant in Mirs Bay, while other minor phytoplankton groups, including eutrophication-tolerant species, constituted the majority in Deep Bay. Phytoplankton community composition tended to be less complex in Deep Bay, suggesting a stressed, unstable and unbalanced ecosystem compared to that in Mirs Bay. Algal blooms occurred more frequently in Mirs Bay, whereas fewer but larger-scale blooms occurred in Deep Bay. Statistically, the combination of all explanatory variables accounted for approximately 55% of the variation in Chlorophyll-a (Chl-a) concentration and less than 20% of the total phytoplankton variation over the 23-year period in the two bays. The high level of nutrients caused by urbanization was not the driving force in the formation of blooms but presumably provided a nutrient base that resulted in blooms with longer durations and covering larger areas.


Assuntos
Baías , Fitoplâncton , China , Ecossistema , Monitoramento Ambiental , Eutrofização , Hong Kong , Estações do Ano , Urbanização
18.
J Environ Manage ; 275: 111180, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32836167

RESUMO

It is increasingly recognized that restoration actions in marine environments are required in order to deal with continued habitat degradation and to support conservation strategies. Restoration success is judged on the ecological outcomes but with limited resources the magnitude of the societal benefits achieved is an important consideration for policy makers. This study demonstrates how the potential non-market benefit value of a deep-sea restoration project might be assessed. The contingent valuation method is employed to elicit the Italian population's willingness to pay for the restoration of the Dohrn deep-sea canyon in the Bay of Naples. Sample selection models that control for the impact of protest zero bidders on benefit value estimation are compared to more traditional modelling approaches. The results indicate a positive willingness to pay for the restoration of the canyon ecosystem and the importance of accounting for protest zero bidders in contingent valuation studies, especially when the environmental good is unfamiliar to respondents. The paper argues that the inclusion of non-market benefit values is particularly important in assessing the potential for marine ecosystem restoration if a true reflection of the value to society of restoring such habitats are to be correctly captured.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Baías
19.
Environ Pollut ; 266(Pt 3): 115245, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32717590

RESUMO

Pharmaceutically active compounds (PhACs) have attracted increasing attention due to their large consumption volumes, high bioactivity and potential ecotoxicity. In this study, a total of 150 commonly used drugs were investigated in sediments of Jiaozhou Bay (JZB). Twenty-five target compounds were detected, of which ten were discovered for the first time in marine sediments. The range of total PhAC content was 3.62-21.4 ng/g dry weight. Ketoprofen (2.49 ng/g), oxytetracycline (1.00 ng/g) and roxithromycin (0.97 ng/g) were the preponderant PhACs. PhACs gradually decreased from east to west, and the distribution of PhACs in the sediment was controlled by the source channel, seawater dynamic process and sediment composition. The diatom, organic matter, and clay proportions in the sediments and the nutrients in the overlying water were the most important environmental factors affecting the distribution of PhACs. PhAC pollution in the sediments of the JZB exhibited an increasing trend. Coprostanol could be used as a chemical indicator of the PhAC concentration in JZB sediments. PhACs were mainly derived from direct pollution due to human fecal excretion in the eastern region. Ofloxacin, tetracycline and oxytetracycline were found to pose high or medium risks to aquatic organisms. It is necessary and urgent to improve the treatment technology of drug residues in sewage treatment plants to decrease the pollution of PhAC residues. With the continuous aging of the global population, the use of PhACs will increase rapidly, which may cause more unpredictable threats to the marine ecosystem. Therefore, the monitoring of PhACs in the marine environment needs to be strengthened, and studies on PhAC occurrence and effects must be considered a priority in global environmental research.


Assuntos
Baías , Poluentes Químicos da Água/análise , China , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Humanos
20.
Sci Total Environ ; 744: 140947, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32721680

RESUMO

Retrospective analysis of water quality monitoring data reveals strong interannual shifts in the spatial distribution of two harmful algal species (Prorocentrum minimum and Karlodinium veneficum) in eutrophic Chesapeake Bay. A habitat model, based on the temperature and salinity tolerance of the two species as well as their nutrient preferences, provides a good interpretation for the observed seasonal progression and spatial distribution of these taxa. It also points to climate-induced variability in the hydrological forcing as a mechanism driving the interannual shifts in the algal distributions: both P. minimum and K. veneficum shift downstream during wetter years but upstream during dry years. Climate downscaling simulations using the habitat model show upstream shifts of the two species in the estuary and longer blooming seasons by the mid-21st century. Salt intrusion due to sea level rise will raise salinity in the estuary and cause these HAB species to migrate upstream, but increasing winter-spring flows may also drive favorable salinity habitat downstream. Warming leads to longer growing seasons of P. minimum and K. veneficum but may suppress bloom habitat during their respective peak bloom periods.


Assuntos
Dinoflagelados , Proliferação Nociva de Algas , Baías , Ecossistema , Estudos Retrospectivos
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