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1.
Artigo | IMSEAR | ID: sea-217198

RESUMO

Anthropogenic activities around the sea ports are capable of causing changes on the physicochemical and microbiological quality of water bodies along the port terminals. Such activities can cause an ecological imbalance in the water quality /ecosystem resulting in extinction of aquatic resources. The aim of this study therefore was to investigate the physicochemical and microbiological quality of surface water along the busy port terminals. Surface water samples were collected from Onne port terminal using sterile containers. The samples were collected during the wet and dry seasons between January to June 2021. The sterile bottles were filled with surface water samples and transported in an ice packed container to the Department of Microbiology Laboratory of the Rivers State University for analyses using standard analytical methods. Statistical analyses were carried out using ANOVA and All pairs tukey-kramer. Results of the physicochemical parameters showed that temperature, total dissolved solids, total suspended solids, nitrate and heavy metals were significantly higher during the dry season than the wet season at P ? 0.05 levels of significance. Seasonal variation with respect to microbial counts shows that Total Heterotrophic Bacteria, Total Heterotrophic Fungi, Total coliforms and Faecal coliforms had a mean value of 3.9±1.77 x 106; 0.8 ±0.05 x 104 ; 7.4 ±1.3 x 104 and 3.6 ±0.17 x 104 colony forming unit per millilitre respectively for wet season while the dry season had 1.6±0.77 x 106 , 0.5 ±0.01 x 104 , 4.6 ±0.17 x 104 and 2.7 ±1.03 x 104 cfu/ml respectively. In this study, the predominant bacterial isolates belonged to the genera of Vibrio, Pseudomonas, Klebsiella, Bacillus, Shigella, Staphylococcus, Salmonella, Proteus, Bacillus and Escherichia. coli. The results of physicochemical and microbiological characteristics including the heavy metals, were detected at concentrations on or below detection limits.. It is therefore suggested that relevant environmental regulatory bodies should maintain regular check to ensure that appropriate standards are maintained around seaports due to beehive of activities.

2.
Chinese Journal of Radiological Health ; (6): 438-443, 2023.
Artigo em Chinês | WPRIM | ID: wpr-988219

RESUMO

Objective To investigate the content of thorium (Th) in surface water in Sichuan Province, China, and to evaluate Th-associated health risk via water intake for residents. Methods Twenty-three monitoring sections were set in main surface water bodies in Sichuan Province. From 2016 to 2021, the Th radioactivity level in the water bodies was measured during dry and normal-water seasons. The health risk of residents was evaluated by calculating radioactive Th intake from the surface water bodies combined with the use of a health risk assessment model. Results The Th radioactivity level of the surface water bodies in Sichuan Province was 0.02-0.67 μ./L. There was no significant difference in the Th radioactivity level of different years or different surface water bodies (P > 0.05). A significant difference was observed in the Th radioactivity level of different water seasons (P < 0.05). The total mean annual committed effective doses of Th in all age groups caused by drinking water and water immersion ranged from 3.14 × 10−8 to 8.75 × 10−7 Sv, all lower than the World Health Organization (WHO)-recommended reference level of 0.1 mSv. The overall carcinogenic risks for residents in all age groups ranged from 3.93 × 10−10 to 1.09 × 10−8, all below the most rigorous control limits issued by WHO and International Commission on Radiological Protection. Conclusion The Th-associated health risk via direct water intake and water immersion in main surface water bodies of Sichuan Province is at an acceptable level. Th in main surface water bodies of Sichuan Province is safe for all age groups.

3.
Chinese Journal of Schistosomiasis Control ; (6): 132-139, 2020.
Artigo em Chinês | WPRIM | ID: wpr-821623

RESUMO

Objective To evaluate the effects of water body environments on the microbial community of Oncomelania hupensis snails in marshlands of the eastern Dongting Lake where natural extinction of O. hupensis snails are found, so as to explore the correlation between the natural extinction of O. hupensis snails and the microbial community in snails. Methods Snails were caged water bodies in the Qianliang Lake marshland (Qianliang Lake regions) where natural extinction of snails was found and in the Junshan Park marshland (Junshan Park regions) in the eastern Dongting Lake for 30 days, and then all snails were collected and identified for survival or death. DNA sequencing of the fungi and bacteria was performed in snails before and after immersion in waters, and the biodiversity and abundance were analyzed. Results The survival rates of O. hupensis snails were 28.0% (70/250) and 64.8% (162/250) in Qianliang Lake regions and Junshan Park regions 30 days after immersion in waters, respectively (χ2 = 81.365, P < 0.01). The number of the fungal community and the biodiversity of the bacterial community were both greater in snails caged in Qianliang Lake regions post-immersion than pre-immersion, and there was a significant difference in the structure of the fungal and bacterial communities. The microbial community with a significant difference included Flavobacteriaceae,which was harmful to O. hupensis snails. Conclusion The water body environment affects the composition of the microbial community in O. hupensis snails in marshlands with natural snail distinction around the eastern Dongting Lake; however, further studies are required to investigate whether the natural distinction of snails is caused by water body environments-induced changes of the microbial spectrum in O. hupensis snails.

4.
Eng. sanit. ambient ; 24(2): 261-269, mar.-abr. 2019. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1012045

RESUMO

RESUMO Previsto na Lei nº 9.433/97 e em legislações estaduais de recursos hídricos, o enquadramento de corpos de água segundo seus usos preponderantes tem sido aplicado em diversas bacias hidrográficas brasileiras. Por ser de uso relativamente recente, pairam muitas dúvidas em detalhes de sua efetiva aplicação. Isso posto, o presente trabalho apresenta uma sugestão de metodologia que vem sendo aplicada pelos autores, compreendendo os diversos passos citados na Resolução CNRH nº 91/08. A metodologia não se pretende definitiva e visa contribuir para a aplicação da importante ferramenta do enquadramento.


ABSTRACT The classification of water bodies according to designated uses is a tool present in the 9.433/97 federal law and has being applied in several Brazilian hydrographic basins. Due to its relatively recent application, there are many doubts about the details of its implementation. The paper suggests a methodology that is being used by the authors, comprising the steps foreseen in Conselho Nacional de Recursos Hídrico's (CNRH) Resolution nº 91/08. Although it is not a definitive methodology, it aims to contribute to the debate about the use of this relevant management tool of water resources.

5.
Chinese Traditional and Herbal Drugs ; (24): 1795-1803, 2019.
Artigo em Chinês | WPRIM | ID: wpr-851184

RESUMO

Objective: To verify the feasibility of vapor-permeable membrane technology for the separation of water bodies containing essential oil of Asari Radix et Rhizoma (ARR) essential oil, and then to apply vapor permeate technology to the separation of more essential oils of traditional Chinese medicine. Methods: The polydimethylsiloxane/polyvinylidene fluoride (PDMS/PVDF) composite flat membrane and polyvinylidene fluoride (PVDF) flat membrane were collected as the membrane material. The oil-bearing water body of ARR volatile oil was separated by vapor permeate technology, and the oil penetration rate of two kinds of membranes was calculated. At the same time, the changes of the composition and content of the essential oil before and after the membrane were analyzed by gas chromatography-mass spectrometry (GC-MS). Results: The results showed that the essential oil penetration rate was significantly higher than that of PDMS/PVDF membrane when PVDF membrane was used as membrane material. GC-MS qualitative analysis results showed that the composition of the essential oil in the penetrants of the two membranes was basically the same as that of the essential oil obtained by the traditional steam distillation method. The content of α-pinene, β-pinene, 3,5-dimethoxytoluene, and methyl eugenol were determined by double internal standard method. The results showed that the content of each component in the PVDF membrane permeation was significantly higher than that of the PDMS/PVDF membrane permeation solution. Conclusion: It is feasible to separate the oil containing water from the essential oil of ARR by vapor permeation membrane technology. Compared with the PDMS/PVDF membrane, the PVDF membrane is more suitable for separating the oil containing water of the essential oil of ARR.

6.
Eng. sanit. ambient ; 23(5): 881-889, set.-out. 2018. tab, graf
Artigo em Português | LILACS | ID: biblio-975149

RESUMO

RESUMO A possibilidade do uso de herbicidas em ecossistema aquático para controle de macrófitas quando em condições de desequilíbrio levou à necessidade de estudos que avaliam a concentração de efeito que seja eficiente e ecologicamente equilibrada, sem causar maiores impactos aos organismos não alvo e ao ecossistema aquático. O glifosato é o princípio ativo de alguns herbicidas e é conhecido pela sua eficácia, amplo espectro de ação e baixa toxicidade. Neste trabalho foi investigada a menor concentração de efeito para controle da Eichhornia crassipes e da Salvinia sp em experimentos realizados em triplicata e observados pelo período de 20 dias após aplicações de glifosato nas concentrações de 6,25; 12,5; 25,0; 50,0 e 100 L.ha-1. Como resultado, verificou-se que apenas a concentração de 100 L.ha-1 apresentou diferença significativa de efeito comparada ao controle. O efeito ao final do vigésimo dia foi superior a 90%, tornando-se aparente a partir do décimo dia. Existiu uma pequena diferença na sensibilidade entre as espécies, no entanto, a concentração de efeito foi semelhante. A dose de 100 L.ha-1 impediu a ocorrência de rebrota, no prazo de 30 dias, e causou efeito residual pobre em espécies vegetais inseridas no ambiente após a aplicação do herbicida.


ABSTRACT The possibility of using herbicides in an aquatic ecosystem, to macrophytes control in unbalanced conditions, led to the need for studies that evaluate the concentration of effect that is effective and ecologically balanced, without causing major impacts to the non-target organisms in the aquatic ecosystem. The glyphosate is the active ingredient of some herbicides and it is known for its efficacy due its broad-spectrum and non-selectivity. This study investigated the minor concentration of effect to control Eichhornia crassipes and Salvinia sp., in experiments conducted in triplicate and observed during a period of 20 days after glyphosate application in the concentrations: 6.25, 12.5, 25.0, 50.0 e 100 L.ha-1. It was verified that only the concentration of 100 L.ha-1 had significant difference of effect when compared to the control. The effect at the end of the twentieth day it was superior to 90%, becoming apparent from the tenth day on. It was observed a small difference in sensibility between the evaluated species; however, the concentration of effect was similar. The dose of 100 L.ha-1 prevented the occurrence of regrowth during thirty days, and caused a residual effect in vegetal species inserted in the environment after the herbicide application.

7.
China Journal of Chinese Materia Medica ; (24): 1642-1648, 2018.
Artigo em Chinês | WPRIM | ID: wpr-687253

RESUMO

To investigate the feasibility of vapor permeation membrane technology in separating essential oil from oil-water extract by taking the Forsythia suspensa as an example. The polydimethylsiloxane/polyvinylidene fluoride (PDMS/PVDF) composite flat membrane and a polyvinylidene fluoride (PVDF) flat membrane was collected as the membrane material respectively. Two kinds of membrane osmotic liquids were collected by self-made vapor permeation device. The yield of essential oil separated and enriched from two kinds of membrane materials was calculated, and the microscopic changes of membrane materials were analyzed and compared. Meanwhile, gas chromatography-mass spectrometry (GC-MS) was used to compare and analyze the differences in chemical compositions of essential oil between traditional steam distillation, PVDF membrane enriched method and PDMS/PVDF membrane enriched method. The results showed that the yield of essential oil enriched by PVDF membrane was significantly higher than that of PDMS/PVDF membrane, and the GC-MS spectrum showed that the content of main compositions was higher than that of PDMS/PVDF membrane; The GC-MS spectra showed that the components of essential oil enriched by PVDF membrane were basically the same as those obtained by traditional steam distillation. The above results showed that vapor permeation membrane separation technology shall be feasible for the separation of Forsythia essential oil-bearing water body, and PVDF membrane was more suitable for separation and enrichment of Forsythia essential oil than PDMS/PVDF membrane.

8.
Eng. sanit. ambient ; 22(3): 429-435, mai.-jun. 2017. tab, graf
Artigo em Português | LILACS | ID: biblio-840420

RESUMO

RESUMO Os objetivos deste trabalho foram avaliar a presença e a concentração dos anti-inflamatórios diclofenaco e naproxeno em um córrego urbano localizado no município de Três de Lagoas, Mato Grosso do Sul, que recebe efluente de uma estação de tratamento de esgoto; e verificar a influência da temperatura da água na ocorrência dos fármacos em águas superficiais. Foi realizado monitoramento dos anti-inflamatórios e dos parâmetros temperatura, pH e oxigênio dissolvido na água durante 12 meses consecutivos (outubro de 2008 a setembro de 2009). Foram coletadas amostras de água mensalmente em seis pontos, representando diferentes seções do córrego. As amostras foram submetidas ao processo de extração em fase sólida e analisadas por cromatografia líquida de alta eficiência. Para verificar a influência da temperatura da água na ocorrência dos anti-inflamatórios diclofenaco e naproxeno nos ambientes aquáticos, utilizou-se um modelo de regressão logística do Statistical Analysis System versão 9.0. Os anti-inflamatórios diclofenaco e naproxeno foram detectados nos diferentes pontos monitorados no Córrego da Onça. Os demais parâmetros avaliados neste estudo foram comparados com os padrões de qualidade de água estabelecidos pela Resolução CONAMA nº 357/2005. A maior concentração do diclofenaco foi detectada no ponto localizado à jusante da estação de tratamento de esgoto do município, enquanto a maior concentração de naproxeno foi registrada na foz do córrego. A temperatura da água influencia de forma inversamente proporcional a ocorrência dos dois anti-inflamatórios no córrego, ou seja, quanto maior a temperatura do corpo hídrico, menor a probabilidade de detecção dos fármacos diclofenaco e naproxeno.


ABSTRACT The aims of this study were to evaluate the presence and concentration of the anti-inflammatory drugs diclofenac and naproxen in an urban stream located in Três Lagoas, Mato Grosso do Sul, Brazil, that receives effluent from a wastewater treatment plant; and to evaluate the influence of water temperature in the occurrence of these drugs into surface waters. Monitoring of both anti-inflammatory and the parameters temperature, pH and dissolved oxygen was held in this water body during 12 consecutive months (October 2008 to September 2009). Water samples were collected monthly at six points representing different sections of the stream. The samples were subjected to solid phase extraction procedure and analyzed by high performance liquid chromatography. To check the influence of water temperature on the occurrence of the anti-inflammatory drugs diclofenac and naproxen in aquatic environments, it was used a logistic model of regression, the Statistical Analysis System version 9.0. The anti-inflammatory drugs diclofenac and naproxen were detected at different points in the Stream of Onça. The other parameters evaluated in this study were compared with the water quality standards established by the CONAMA Resolution 357/2005. The highest concentration of diclofenac was detected in the point located downstream of the wastewater treatment plant of the city, while the largest concentration of naproxen was recorded at the mouth of the stream. The water temperature influence, in an inversely proportional way, the occurrence of both anti-inflammatory in the stream, the higher the temperature the lower the water body probability of detection of drug diclofenac and naproxen.

9.
Rev. biol. trop ; 62(supl.2): 81-96, abr. 2014. graf, tab
Artigo em Espanhol | LILACS | ID: lil-753758

RESUMO

Spatial and temporal variation patterns in aquatic macroinvertebrates of Tecocomulco Lake, Hidalgo (México). Lake Tecocomulco, Hidalgo, is a relic of the ancient lakes of Anahuac, important for the conservation of resident and migratory birds. However, the composition of aquatic macroinvertebrates is unknown; this is an important gap in conservation as they play an important role in the food web. This study analyzed the spatial and temporal variations in macroinvertebrate assemblages and their relationship with habitat characteristics. We carried out four monitoring campaigns covering the rainy and dry seasons. The monitoring was conducted at six study sites (four in the littoral zone and two in the middle part of the lake), environmental factors were recorded at each study site, water samples were collected for their physical and chemical analysis and aquatic macroinvertebrates were collected. A principal component analysis (PCA) was used to group study sites based on physical and chemical characteristics. Richness of taxa was analysed with rarefaction. We assessed the importance value index of each taxon (considering their frequency of occurrence and abundance). Similarity analyzes were performed between study sites and similarity of taxa with indices of Jaccard and Bray-Curtis, respectively. We performed a canonical correspondence analysis (CCA) between environmental factors and macroinvertebrate taxa. The PCA showed a marked seasonal variation represented by warm periods, with high values of conductivity, alkalinity, hardness, sulfates, and macronutrients (N and P) and the cold period with low values. We found a total of 26 taxa of aquatic macroinvertebrates and the highest richness was found in August. The Jaccard similarity analysis found differences between the littoral area and the limnetic zone, which differ also in the composition of macrophytes. The littoral zone had the highest taxa richness of macroinvertebrates and macrophytes, while the lowest diversity was found in the offshore zone. The CCA related physicochemical characteristics of the water body with macroinvertebrate taxa showing the influence of both physicochemical characteristics and the composition of macrophytes in the spatio-temporal patterns of aquatic macroinvertebrates in the lake. The dominance of Corixidae highlights a strong grazing activity in the lake and in turn suggests an important amount of food available for higher trophic levels. Our study shows that the macroinvertebrates of Tecocomulco Lake have spatial and seasonal variations that are related to both environmental and biotic factors with groups being dominant. Rev. Biol. Trop. 62 (Suppl. 2): 81-96. Epub 2014 April 01.


La Laguna de Tecocomulco (Hidalgo) es un relicto de los antiguos Lagos del Anáhuac con suma importancia para la conservación de aves acuáticas. No obstante, se desconoce su composición de macroinvertebrados. En el presente estudio se analizaron las variaciones espaciales y temporales de los macroinvertebrados acuáticos de la laguna. Se realizaron cuatro campañas de monitoreo (lluvias y estiaje). Se estudiaron seis sitios (litorales y en interior de la laguna), se registraron factores ambientales, se determinaron parámetros de calidad del agua y se recolectaron macroinvertebrados acuáticos. Se obtuvo la riqueza de familias y se calculó su Índice de Valor de Importancia. Se realizaron análisis multivariados de ordenación por componentes principales (ACP) con base en sus características físicas y químicas y de similitud entre sitios y familias con los índices de Jaccard y Bray-Curtis. Tambien se hizo un análisis de correspondencias canónicas (ACC) de factores ambientales y macroinvertebrados acuáticos y macrófitas. El ACP mostró la variación estacional, con el período cálido (mayo y agosto) y el periodo frío (noviembre y enero) mostrando altos valores de conductividad, alcalinidad, dureza, sulfatos y macronutrientes (N y P). Se encontraron 26 familias de macroinvertebrados, con la máxima riqueza en agosto. El análisis de similitud de Jaccard diferenció los sitios litorales por su mayor riqueza de familias de la zona limnética, mismos que presentan diferencias en la composición de macrófitas. El estudio revela que la Laguna de Tecocomulco tiene variaciones espaciales y temporales relacionadas tanto con factores ambientales como bióticos con la presencia de grupos dominantes. En ese sentido, y considerando su diversidad de macroinvertebrados, la Laguna de Tecocomulco debe ser sujeta a un plan de conservación y manejo.


Assuntos
Animais , Ecossistema , Monitoramento Ambiental/métodos , Invertebrados/classificação , Lagos , Densidade Demográfica , Dinâmica Populacional , Estações do Ano
10.
Rev. biol. trop ; 54(2): 639-645, jun. 2006. mapas, graf, tab
Artigo em Espanhol | LILACS | ID: lil-492039

RESUMO

We evaluated fish community, species richness and diversity in a temporal water body of Rio Frio, Caño Negro National Wildlife Refuge. These evaluations were done for three categories of water levels: low (below 1.5 m), intermediate (between 1.5 and 3.0 m) and high (deeper than 3 m). A total of 10,264 individuals were collected (nine families, 18 genera and 21 species). The most abundant species were Poecilia gillii (37%) and Astyanax aeneus (19%) and the least abundant were Ophisternon aenigmaticum (0.06%) and Rhamdia nicaraguensis (0.05%). The highest values in diversity (H' = 2.07), in the inverse of the Simpson index (1/D = 6.2) and of the Berger-Parker (1/d = 4.2), were recorded in the deepest water category. Diversity differed clearly among water levels (p < 0.001). The high and intermediate categories were the most similar (conglomerate analysis: 72.9%). Out of the 21 species captured, only O. aenigmaticum constitutes a new record for the ichthyofauna of Rio Frio in the Caño Negro National Wildlife Refuge. The temporal water body of the Rio Frio, considered in this study in the Playuela sector of Caño Negro National Wildlife Refuge is a nonhomogeneous ichthyological system.


Se evaluó la diversidad, el dominio y la equidad de la ictiofauna en un cuerpo de agua temporal en el río Frío, sector Playuela, Refugio Nacional de Vida Silvestre Caño Negro, según tres categorías del nivel de agua (baja [menor a 1.5 m], media [entre 1.5 y 3.0 m] y alta [mayor de 3.0 m]). Se recolectaron 10 264 individuos, pertenecientes a nueve familias, 18 géneros y 21 especies. Las especies que aportaron el mayor número de individuos fueron Poecilia gillii (37%) y Astyanax aeneus (19%); mientras que las menos abundantes fueron Ophisternon aenigmaticum (0.06%) y Rhamdia nicaraguensis (0.05%). El valor más alto en la diversidad de especies se registró en la categoría alta (H’=2.07); coincidiendo con los valores más altos en el inverso del índice de Simpson (1/D=6.2) y de Berger- Parker (1/d=4.2). De acuerdo con su diversidad, todas las categorías consideradas para el nivel de agua, mostraron diferencias estadísticas altamente significativas entre sí (p<0.001). El análisis de conglomerados reconoció a las categorías alta y media como las más similares (72.9%).De las 21 especies capturadas, solamente O. aenigmaticum constituye un nuevo registro para la ictiofauna de Caño Negro. Este cuerpo de agua estacional es un sistema cuya ictiofauna fluctúa temporalmente.


Assuntos
Animais , Biodiversidade , Peixes/classificação , Água Doce/química , Costa Rica , Densidade Demográfica , Dinâmica Populacional , Especificidade da Espécie , Estações do Ano , Peixes/fisiologia , Rios
11.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM | ID: wpr-684821

RESUMO

In this experiment six methods,calcium chloride(CaCl_(2)) precipitation,polyethylene glycol(PEG,pH7.0) precipitation,polyethylene glycol(PEG,pH11.5) precipitation,aluminum chloride(AlCl_(3)) precipitation,Amicon Utcra centrifugal filter devices and cellulose nitrate membrane were used to concentrate the vaccine poliovirus type 1(PV_(1)) added to water body;experimental conditions for concentration were selected and optimized.The results showed that two methods,CaCl_(2)and PEG(pH 7.0) precipitation were suitable for concentrating virus in large volumes of water while amicon utcra centrifugal filter devices for small ones.The virus recovery of the three methods reached a 100% rate.

12.
Chinese Journal of Schistosomiasis Control ; (6)1991.
Artigo em Chinês | WPRIM | ID: wpr-562320

RESUMO

Objective To evaluate the effect of elimination of schistosomiasis infectivity in water body by applying molluscicide on transmission marshland outside an embankment in Dongting Lake.Methods Two patches of transmission marshland with similar Oncomelania snails and infectious snails density in the northern part of eastern Dongting Lake regions were selected as molluscicide trail and control groups,respectively,and the snails and water body infectious indicators were investigated and compared between them.Results Adjusted death rate of snails in the trail group 15 days after applying molluscicide was 94.13%,without infected snails.The infection rate of sentinel mice in the trial group 50 days after applying molluscicide was 100.00%,with average 56.6 worms per mice.The infection rate of sentinel mice in the control group without molluscicide was also 100.00%,with average 147.8 worms per mice.Conclusions In transmission marshland areas outside the embankment of rivers or lakes,it is impossible for focus mollusciciding to eliminate the infectivity of schistosomiasis in water body,yet possible to reduce the degree of infectivity to a certain extent.

13.
Chinese Journal of Schistosomiasis Control ; (6)1989.
Artigo em Chinês | WPRIM | ID: wpr-560922

RESUMO

Objective To evaluate the efficiency of prevention of Oncomelania snail dispersal with the mode of leading water from middle level of water body by the culvert pipelinet in the electric pumping station. Methods The snails were detected in the floats by riverhead and the irrigation areas, and the snails were hold up by the block in the exit of pump. The snail investigation was carried out in the irrigation system areas and the results were compared between the study area and the control area. Results The snails were discovered in the floats of riverhead of the electric pumping station. However, there were no any snails in the exit of pump after the block snail treatment and no any snails in the irrigation areas, either. There were snails in the control areas Conclusion The mode of leading water from middle level of water body by the culvert pipelinet is very effective for the prevention of Oncomelania snail dispersal.

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