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1.
Braz. j. biol ; 79(1): 120-126, Jan.-Mar 2019. tab, graf
Article in English | LILACS | ID: biblio-984005

ABSTRACT

Abstract We evaluated the response of the biomass of aquatic macrophytes under limnological changes after water level fluctuation (WLF) of two tropical reservoirs (R1 and R2), located in northeastern Brazil. Initially we tested the hypothesis that post-WLF limnological conditions and biomass of macrophytes increase or decrease, depending on the variable or species. We monitored a 4 × 50 m permanent plot, in four expeditions per period (pre- or post-WLF), assessing species biomass and 10 limnological variables. We utilized 0.25 × 0.25 m quadrats for biomass. Once the effect of WLF in limnological variables and species biomass was confirmed, we utilized Canonical Correspondence Analysis to understand the relationship between limnological variables and species biomass. The abundant and/or dominant species in pre-WLF of R1 ( Pistia stratiotes, Eichhornia crassipes and Salvinia auriculata) and R2 (Paspalidium geminatum and S. auriculata) reduced their biomass post-WLF and were correlated with temperature, total phosphorous and nitrate. The reduced biomass of P. stratiotes, E. crassipes and S. auriculata in post-WLF widened resource availability, allowing coexistence of species. Therefore, we suggest that the change of limnological conditions in post-WLF in artificial lakes acts only as a moderator factor of the interspecific interaction (especially coexistence), without direct relation between these conditions and species biomass.


Resumo Avaliamos a resposta da biomassa de macrófitas aquáticas às alterações ambientais após flutuação do nível de água (WLF) de dois reservatórios tropicais (R1 e R2), localizados no Nordeste do Brasil. Inicialmente, testamos a hipótese de que após uma WLF as condições limnológicas e a biomassa das macrófitas aumentam ou diminuem, dependendo da variável ou espécie. Por isso, monitoramos uma parcela permanente de 4 × 50 m, em quatro amostragens por período (pré ou pós-WLF), avaliando a biomassa de espécies e 10 variáveis ​​limnológicas. Utilizamos quadrados de 0,25 × 0,25 m na amostragem da biomassa. Uma vez que o efeito do WLF em variáveis limnológicas e biomassa das espécies foi confirmado, utilizamos a Análise de Correspondência Canônica para compreender a relação das variáveis ​​limnológicas com a biomassa de espécies. As espécies abundantes e/ou dominantes no pré-WLF de R1 (Pistia stratiotes, Eichhornia crassipes e Salvinia auriculata ) e R2 (Paspalidium geminatum e S. auriculata ) reduziram sua biomassa pós-WLF, correlacionando-se diretamente com temperatura, fósforo total e nitrato. A redução da biomassa de P. stratiotes , E. crassipes e S. auriculata em pós-WLF ampliou a disponibilidade de recursos, permitindo a coexistência de espécies. Portanto, sugerimos que a mudança das condições limnológicas no pós-WLF em lagos artificiais atua apenas como um fator moderador da interação interespecífica (em especial a coexistência), sem relação direta entre essas condições e a biomassa das espécies.


Subject(s)
Water Movements , Lakes/analysis , Biomass , Magnoliopsida/physiology , Brazil , Lakes/chemistry , Water Resources , Aquatic Organisms/physiology
2.
Chinese Journal of Endemiology ; (12): 423-427, 2017.
Article in Chinese | WPRIM | ID: wpr-620104

ABSTRACT

Objective To evaluate the efficacy of a sustained releasing mosquito larvicide package against larval breeding and its impact on water and plant,in order to provide a scientific evidence for its application in control and prevention of Dengue.Methods Guangzhou Center for Disease Control and Prevention was chosen as the test place.Twenty test sites were set up,2 bags of sustained releasing larvicides package,1 bag of sustained releasing larvicides package,3 g 1% temephos granules and nothing were put into 4 glass bottles for each test site from July to December in 2014,respectively.The 4 glass bottles were called high dose (H) group,low dose (L)group,positive control (P) group and blank control (B) group,respectively.The 4 groups were observed at intervals of 10 days for 19 times.Environmental air temperature,turbidity of water,number of larvae and damage of plant were recorded.And 5 test sites were selected to collect water specimen.The chemical oxygen demand,ammonia nitrogen concentration and temephos concentration of water specimen were detected.Results The larval breeding rates were 0 (0/380),1.1% (4/380),0.8% (3/380) and 63.4% (241/380),damage rates of plant were 5.0% (19/380),5.5% (21/380),4.7% (18/380),4.7% (18/380) and turbidty rates of water were 24.5% (93/380),19.7% (75/380),33.4% (127/380) and 20.3% (77/380) in H,L,P and B groups,respectively.Statistically significant differences were seen in larval breeding rate and turbidity rate of water between different groups (x2 =823.565,24.715,all P < 0.05),but they were not seen in damage rate of plant (x2 =0.332,P > 0.05).The temephos concentrations were 1.24,0.78 and 2.33 mg/L in H,L and P groups,respectively.Statistically significant differences were seen in temephos concentration between different groups (H =35.426,P < 0.01),but they were not seen in chemical oxygen demand and ammonia nitrogen concentration (H =0.239,0.013,all P > 0.05).Conclusions The sustained releasing package of mosquito larvicide makes less pollution to water and has no impact on water turbidity.Moreover,it doesn't damage the aquatic plant.The efficacy of the sustained releasing package of mosquito larvicide could effectively prevent mosquito larval breeding in Dengue epidemic period.

3.
Acta sci., Biol. sci ; 38(4): 419-427, oct.-dec. 2016. ilus
Article in English | LILACS | ID: biblio-831619

ABSTRACT

The diaspore bank is an important component of biological diversity acting mainly as storage and source of diaspores, which also indicate dynamics and patterns of maintenance of plant diversity. We tested the hypothesis that the diaspore bank would be the responsible factor for the maintenance of the aquatic plant species, used two techniques to evaluate the diaspore bank: seedling emergence and direct counting of field samples. Density and richness of the diaspore bank were correlated with plant cover of the aquatic macrophyte communities and also with the euphotic zone radiation in different phases of the hydrological cycle. The diaspore bank is a key factor in maintenance of aquatic macrophyte assemblages in this pond. Nymphaea amazonum was one of the dominant species in the pond and presented temporally peaks of plant cover. Furthermore, depth allowed induction of germination of stored diaspores. Therefore, the diaspore bank may predict which species colonizes a site when environmental characteristics are favorable and allows inferring which processes are linked to changes in structure of aquatic macrophyte assemblages. These mechanisms are the means for recovery of macrophyte species under natural disturbances, represented by water level oscillations in floodplains.


O banco de diásporos é um componente importante da diversidade biológica atuando principalmente como armazenamento e fonte de diásporos, que também indicam a dinâmica e os padrões de manutenção da diversidade vegetal. Testamos a hipótese de que o banco de diásporos seria o fator responsável pela manutenção das espécies de plantas aquáticas, utilizando duas técnicas para avaliar o banco diásporo: emergência das plântulas e contagem direta de amostras de campo. Densidade e riqueza do banco de diásporos foram correlacionadas com cobertura vegetal das comunidades de macrófitas aquáticas e também com a radiação da zona eufótica em diferentes fases do ciclo hidrológico. O banco de diásporos é um fator chave na manutenção das assembleias de macrófitas aquáticas nesta lagoa. Nymphaea amazonum foi uma das espécies dominantes na lagoa temporalmente, apresentou picos de cobertura vegetal. Além disso, a profundidade permitiu a indução da germinação de diásporos armazenados. Portanto, o banco de diásporo é um preditor de quais espécies colonizarão um local quando as características ambientais são favoráveis e permite inferir que os processos estão ligados a mudanças na estrutura das assembleias de macrófitas aquáticas. Estes mecanismos são os meios para a recuperação de espécies de macrófitas sob as perturbações naturais, representados por oscilações do nível de água nas planícies aluviais.


Subject(s)
Ecology , Seed Bank , Wetlands
4.
Mycobiology ; : 231-238, 2015.
Article in English | WPRIM | ID: wpr-729640

ABSTRACT

A total of 4 aquatic plants, Eleocharis kuroguwai Ohwi, Hydrocharis dubia Backer, Salvinia natans All., and Zizania latifolia Turcz., were sampled from representative two wetlands of South Korea. A total of 38 endophytic fungal strains were isolated from aquatic plants native to the Daepyeong wetland, and 27 strains were isolated from the Jilnal wetland. The internal transcribed spacer regions of fungal isolates were sequenced and a phylogenetic analysis was performed. In addition, endophytic fungal diversity from each wetland and host plant species was deduced. A total of 25 fungal genera were purely isolated, and 16 fungal genera were isolated from each of the two wetlands. Commonly isolated genera from both wetlands were Aspergillus, Cladosporium, Clonostachys, Fusarium, Leptosphaeria, Penicillium, and Talaromyces. This study revealed that fungal diversity varied with environmental conditions and by host plant in representative two wetlands.


Subject(s)
Aspergillus , Cladosporium , Eleocharis , Fresh Water , Fungi , Fusarium , Korea , Penicillium , Plants , Talaromyces , Wetlands
5.
Mycobiology ; : 87-91, 2015.
Article in English | WPRIM | ID: wpr-729855

ABSTRACT

Eighteen endophytic fungi with different colony morphologies were isolated from the roots of Nymphoides peltata growing in the Dalsung wetland. The fungal culture filtrates of the endophytic fungi were treated to Waito-c rice seedling to evaluate their plant growth-promoting activities. Culture filtrate of Y2H0002 fungal strain promoted the growth of the Waito-c rice seedlings. This strain was identified on the basis of sequences of the partial internal transcribed spacer region and the partial beta-tubulin gene. Upon chromatographic analysis of the culture filtrate of Y2H0002 strain, the gibberellins (GAs: GA1, GA3, and GA4) were detected and quantified. Molecular and morphological studies identified the Y2H0002 strain as belonging to Aspergillus clavatus. These results indicated that A. clavatus improves the growth of plants and produces various GAs, and may participate in the growth of plants under diverse environmental conditions.


Subject(s)
Aspergillus , Fresh Water , Fungi , Gibberellins , Plants , Seedlings , Tubulin , Wetlands
6.
Acta amaz ; 40(4): 729-736, dez. 2010. tab
Article in Portuguese | LILACS, VETINDEX | ID: lil-570429

ABSTRACT

Montrichardia linifera (Araceae), conhecida popularmente como 'aninga', faz parte dos ecossistemas de várzea da Amazônia e da dieta natural de animais como peixe-boi, tartarugas, peixes, búfalo e gado. Com o objetivo de contribuir para o conhecimento químico e valor nutricional da mesma, folhas e frutos de M. linifera foram coletados às margens dos rios Guamá e Maratauíra, no Estado do Pará, Brasil. Em folhas e frutos foram realizadas análises de umidade, resíduo mineral fixo (cinzas), lipídios, proteínas, fibra bruta, concentração de carboidratos e valor calórico. A composição mineral (Ca, Mg, Cu, Fe, Zn e Mn) foi obtida por espectrometria de absorção atômica de chama. Observou-se que tanto as folhas quanto os frutos da aninga, apesar de calóricos (289,75 kcal e 355,12 kcal, respectivamente), possuem baixo valor protéico (0,44% e 0,24 %, respectivamente). As concentrações de manganês obtidas (folha = 3279,46 mg kg-1e fruto = 18151,53 mg kg-1) foram consideradas tóxicas, extrapolando o limite máximo tolerável para ruminantes (1000 mg kg-1). A M. linifera, tem capacidade de absorver e bioacumular grandes quantidades de Ca, Mg e Mn presentes no solo, o que torna inadequada a sua utilização exclusiva na alimentação de quelônios, bovinos e bubalinos, havendo necessidade de mais estudos para sua aplicação como parte da ração.


The aninga (Montrichardia linifera, Araceae) is often found in the floodplain ecosystems of the Amazon and is the natural diet of animals such as manatees, turtles, fish, buffalo and cattle. Aiming to contribute to the chemical knowledge and nutritional value of this plant, leaves and fruits of M. linifera were collected on the banks of the Guama and Maratauira rivers, Para State, Brazil. We determined the moisture content, ash mineral composition, lipids, protein, fiber, carbohydrate and caloric value of the fruits and leaves. The mineral composition (Ca, Mg, Cu, Fe, Zn and Mn) was obtained by flame atomic absorption spectrometry. The leaves and the fruits of M. linifera had caloric values of 289.75 kcal and 355.12 kcal, respectively; and a low protein concentration, 0.44% for leaves and 0.24% for fruits. Manganese concentrations were 3279.46 mg kg-1 for leaves and 18151.53 mg kg-1 for fruits. These Mn concentrations are considered toxic, as they exceed the maximum tolerable for the ruminants (1000 mg kg-1). The M. linifera has the capacity to absorb and bioaccumulate large amounts of Ca, Mg and Mn in the soil, which makes it inappropriate for exclusive use as food for turtles, cattle and buffaloes, requiring more studies for its application as part of the diet.


Subject(s)
Plant Leaves/chemistry , Araceae/chemistry , Fruit/chemistry , Nutritive Value , Ruminants , Amazonian Ecosystem
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