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1.
Mar Pollut Bull ; 128: 234-239, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29571368

RESUMO

The sensitivity of the 15 indicators included in a complex aggregation method (Nested Environmental status Assessment Tool), applied to a case study in the Caspian Sea in Iran, has been studied to discriminate between areas impacted and non-impacted by bathing activities. Two methods were used: (i) the 15 indicators were grouped into four groups (physicochemical, bacteria, plankton, and benthos) and each group was investigated separately (one-way sensitivity analysis), calculating NEAT values after omitting each group independently; and (ii) indicators were selected randomly, using 1000 Monte Carlo iterations, and removing from 1 to 14 indicators at each iteration. The results revealed that the abundance of Pontogammarus was the single indicator that made the difference in assessing the status among locations, differentiating bathing and non-bathing areas. Hence, this indicator is regarded as a monitoring element detecting the impacts produced by a management measure (beach nourishment) taken by the authorities to maintain the bathing activity.


Assuntos
Anfípodes/crescimento & desenvolvimento , Praias/normas , Biomarcadores Ambientais , Monitoramento Ambiental/métodos , Modelos Teóricos , Água do Mar , Animais , Análise da Demanda Biológica de Oxigênio , Ecossistema , Irã (Geográfico) , Oceanos e Mares , Salinidade , Água do Mar/química , Água do Mar/microbiologia , Software , Temperatura , Microbiologia da Água/normas
2.
Sci Total Environ ; 575: 1130-1138, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27697341

RESUMO

This study was conducted to determine Microcystin LR concentration in the aquatic ecosystem of the Anzali wetland in Iran. Extraction and detection of MC-LR from the water and fish samples was conducted by the SPE and HPLC-UV apparatus. Our results showed that among toxic cyanobacteria, Anabaena was the dominant genera during the study period. The results indicated that MC-LR content in water ranged from 0.18 to 3.02µg/L in dissolved fraction and undetectable level to 1.13µg/L in cellular fraction, in all three seasons. The results of PCA revealed that the environmental parameters including EC, Chl-a, PO43-, pH and temperature were the most effective factors influencing the MC-LR production. Results further showed the mean concentration of MC-LR in muscle and liver of silver carp ranged from 10.12 to 40.98 and from undetectable to 44.34µg/kg w.w, respectively. The mean concentration of MC-LR in northern pike was 15.18 to 35.1µg/kg w.w in muscle and undetectable to 51.91µg/kg w.w in liver samples. Our results suggest that consumption of fish harvested from the Anzali wetland seems to be unsafe for humans, based on obtained estimated daily intake values which were higher than the tolerable daily intake value recommended by WHO. In addition, bioaccumulation factor of MC-LR in edible tissues of fish was estimated based on lipid normalization. The results showed that the BAF of MC-LR in silver carp (1047±185L/kg of lipid) was lower than the northern pike (1272±185L/kg of lipid), although the difference was not significant.


Assuntos
Carpas , Cadeia Alimentar , Microcistinas/análise , Áreas Alagadas , Anabaena , Animais , Humanos , Irã (Geográfico) , Toxinas Marinhas , Distribuição Tecidual
3.
Chemosphere ; 159: 584-594, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27343865

RESUMO

This study evaluates the impact of anthropogenic activities on the Shahrood River using water physico-chemical variables and macroinvertebrates data sets obtained over a period of 12 months between February 2012 and February 2013 at 8 sampling sites. Biotic indices i.e. FBI and BMWP based on macroinvertebrates and physico-chemical indices (MPI, HPI and NSF-WQI) were employed to evaluate the water quality status in connection with natural- and human-induced pressures. Based on physico-chemical indices, water quality was categorized as low polluted level and it is suitable for drinking purposes. The water quality based on biotic indices was related to the anthropic activities; a clear deterioration of the water quality was observed from upstream to downstream sites. The water quality along the river changed from very good (class I; reference sites) to good (class II; midstream sites) and turned into moderate (class III) and poor (class IV) quality (downstream sites). These findings indicate that biotic indices are more powerful indicators in assessing water quality than physico-chemical indices. Allocapnia, Glossosoma and Hesperoperla were exclusively related to least disturbed sites, and Naididae, Orthocladiinae and Ecdyonurus were found in sites showing notable degradation. Our results recommended that the use of macroinvertebrates could be employed as a cost-effective tool for biomonitoring and controlling of polluted riverine ecosystems in the Middle East. Finally, the results from this study may be useful not only for developing countries, but also for any organization struggling to use macroinvertebrate based indices with restricted financial resources and knowledge.


Assuntos
Rios/química , Poluentes Químicos da Água/análise , Animais , Ecossistema , Monitoramento Ambiental/métodos , Invertebrados/classificação , Invertebrados/crescimento & desenvolvimento , Invertebrados/fisiologia , Poluição Química da Água/estatística & dados numéricos , Qualidade da Água
4.
J Sci Food Agric ; 92(12): 2500-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22467477

RESUMO

BACKGROUND: The nutritional compositions of two edible red (Gracilaria salicornia) and green (Ulva lactuca) seaweeds were determined to evaluate their possible uses as potential food ingredients. RESULTS: In general, these species contained limited amounts of lipids ranging between 0.99 and 2.00 g 100 g(-1) dry weight) and considerably high amount of minerals, especially in G. salicornia (38.91 g 100 g(-1) d.w.). The crude protein values varied between 9.58 and 10.69 g 100 g(-1) d.w. Amounts for total amino acids were 889.78 ± 22.64 mg g(-1) protein d.w. in G. salicornia and 543.3 ± 15.14 mg g(-1) protein d.w. in U. lactuca. The most abundant fatty acids were C12:0, C16:0, C20:4 ω6 and C22:5 ω3, in addition to C18:1 in G. salicornia. Both seaweed species were balanced sources of ω3 and ω6 fatty acids with a ratio of ω6/ω3 that varied between 1.2 and 1.17. Between the seaweeds investigated, high levels of K (2414.02-11 380.06 mg 100 g(-1) d.w.) were observed and the amounts of Ca, Na and Fe were higher than those reported for land plants. CONCLUSIONS: Thus, G. salicornia and U. lactuca may be utilised as value-added products for human nutrition purposes.


Assuntos
Gorduras na Dieta/análise , Proteínas Alimentares/análise , Gracilaria/química , Minerais/análise , Alga Marinha/química , Oligoelementos/análise , Ulva/química , Dieta , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-6/análise , Humanos , Valor Nutritivo
5.
J Phycol ; 48(2): 285-92, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27009718

RESUMO

This study was conducted to create a nutritional database on brown seaweeds and to popularize their consumption and utilization in Iran. The fatty acid contents, amino acids profiles, and certain mineral elements composition of some brown seaweeds, Padina pavonica (L.) Thivy, Dictyota dichotoma (Huds.) J. V. Lamour., and Colpomenia sinuosa (Mert. ex Roth) Derbés et Solier were determined. Total lipid content ranged from 1.46 ± 0.38 to 2.94 ± 0.94 g · 100 g(-1) dry weight (dwt), and the most abundant fatty acids were C16:0, C18:1, C20:4 ω6, and C20:5 ω3. The unsaturated fatty acids predominated in all species and had balanced sources of ω3 and ω6 acids. Highest total polyunsaturated fatty acid (PUFA) levels occurred in C. sinuosa. The protein content of D. dichotoma was 17.73 ± 0.29 g · 100 g(-1) dwt, significantly higher than the other seaweeds examined. Among amino acids essential to human nutrition, methionine (Met; in D. dichotoma and P. pavonica) and lysine (Lys; in C. sinuosa) were present in high concentrations. The crude fiber content varied by 9.5 ± 11.6 g · 100 g(-1) dwt in all species. Chemical analysis indicated that ash content was between 27.02 ± 0.6 and 39.28 ± 0.7 g · 100 g(-1) dwt, and that these seaweeds contained higher amounts of both macrominerals (7,308-9,160 mg · 100 g(-1) dwt; Na, K, Ca) and trace elements (263-1,594 mg · 100 g(-1) dwt; Fe, Ni, Mn, Cu, Co) than have been reported for edible land plants. C. sinuosa had the highest amount of Ca, Fe, and a considerable content of Na was measured in P. pavonica.

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