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1.
J Environ Biol ; 2020 May; 41(3): 613-622
Article | IMSEAR | ID: sea-214519

ABSTRACT

Aim: The study aimed to identify and document major honey bee flora, their blooming seasons (floral calendar), density and frequency, beekeeping potential areas, and place radius for the major bee flora of the Al-Baha region.Methodology: To identify the honey bee flora of al-Baha region, 420 quadrates were established in different seasons and ecological zones. Plants as honey bee forages were identified through observation of the foraging of honey bees on the flowers for nectar or/and pollen. The density and frequency of each plant was calculated, density and radius maps for major honey bee plants were made using the Arc-Map. Canonical Correspondence Analysis (CCA) was carried out for major honey bee plants using MVSP software. Results: The results showed that more than 550 species of flowering plants were recorded in the study areas, of which 204 plant species belonging to 58 families were identified as honey bee plants. However, only 9 species were found to be an important source of major honeys in the region. The largest number (13%) of honey bee plants was recorded for the family Asteraceae, followed by Lamiaceae, Euphorbiaceae, Fabaceae and Mimosaceae each with 13 (6.4%), 11 (5.4%), 11 (5.4%) and 10 (4.9%) plants, respectively. Each of the remaining families had 1 to 8 species. Interpretation: The radius maps, as well as the blooming periods of honey bee flora will guide beekeepers to move their colonies during the peak flowering periods

2.
Braz. arch. biol. technol ; 60: e17160304, 2017. tab, graf
Article in English | LILACS | ID: biblio-839071

ABSTRACT

ABSTRACT The effect of nutrients on the total lipid content and fatty acid profile of Scenedesmus obliquus isolated from the south coast of the Caspian Sea was evaluated. The nutritional compositions of the media impacted the growth rate and biomass of S. obliquus that ranged from 0.175 day-1 to 0.209 day-1and 0.92 gr·l-1 to 1.79 gr·l-1, respectively. The alga grew better in the medium which was characterized by higher levels of sodium and trace elements such as Fe, Mn, Mo, and Co and poor in N and P as compared with the other media. The highest level of the total lipid (32%) and the highest values of saturated fatty acids, in particular palmitic acid also were positively correlated with these nutrients. Peaks in polyunsaturated fatty acids (43.7 %), especially α-linolenic acid (28.4%) were related to N and P, but its correlation with K and Mg was more evident. The most important factors correlated with high amount of monounsaturated fatty acids were also N and P, followed by K and Mg to a lesser extent. This study demonstrated that the same algal strain may be a source of different amount of fatty acids, depending on the composition of the culture medium.

3.
J Biosci ; 2014 Sep; 39 (4): 643-657
Article in English | IMSEAR | ID: sea-161977

ABSTRACT

Limnological data of four high altitude lakes from the cold desert region of Himachal Pradesh, India, has been correlated with cyanobacterial diversity. Physico-chemical characteristics and nutrient contents of the studied lakes revealed that Sissu Lake is mesotrophic while Chandra Tal, Suraj Tal and Deepak Tal are ultra-oligotrophic. Based on morphology and 16S rRNA gene sequence, a total of 20 cyanobacterial species belonging to 11 genera were identified. Canonical correspondence analysis distinguished three groups of species with respect to their occurrence and nutrient/physical environment demand. The first group, which included Nostoc linckia, N. punctiforme, Nodularia sphaerocarpa, Geitlerinema acutissimum, Limnothrix redekii, Planktothrix agardhii and Plank. clathrata, was characteristic of water with high nutrient content and high temperature. The second group, including Gloeocapsopsis pleurocapsoides, Leptolyngbya antarctica, L. frigida, Pseudanabaena frigida and N. spongiaeforme, occurred in oligotrophic water with high pH and low temperature. The distribution of third group of Cyanobium parvum, Synechocystis pevalekii, L. benthonica, L. foveolarum, L. lurida, L. valderiana, Phormidium autumnale and P. chalybeum could not be associated with a particular environmental condition because of their presence in all sampling sites. [Singh Y, Khattar JIS

4.
Asian Pacific Journal of Tropical Medicine ; (12): S610-S616, 2014.
Article in Chinese | WPRIM | ID: wpr-951689

ABSTRACT

Objective: To report the relationship of vegetation structure and environmental gradient and physiochemical properties of soil at Nikyal valley, Azad Jammu and Kashmir Methods: A survey of natural vegetation and soil of Nikyal valley was undertaken. Phytosociological survey was conducted by using Braun-Blanquet's approach. The study also investigated the vegetation structure and its relationship with altitude and edaphic factors. The floristic data was analyzed by cluster anlaysis, detrended correspondence analysis and canonical correspondence analysis using CANACOO 5.0. Results: A total of 110 plant species and 13 stands were merged into five major associations as dema rcated by cluster analysis and detrended correspondence analysis. The associations were Olea- Pinus- Themeda association, Myrsine- Rhus- Quercus association, Quercus- Rubus- Pinus association and Quercus association. Soil organic matter, saturation, pH and altitude play the major role in distribution of species. Conclusions: The variation in vegetation structure is controlled by the altitudinal gradient and physiochemical properties of soil. These results indicate a deteriorated forest structure and reduced regeneration pattern, demanding immediate attention of forest management authorities.

5.
Asian Pacific Journal of Tropical Medicine ; (12): S610-6, 2014.
Article in English | WPRIM | ID: wpr-820154

ABSTRACT

OBJECTIVE@#To report the relationship of vegetation structure and environmental gradient and physiochemical properties of soil at Nikyal valley, Azad Jammu and Kashmir .@*METHODS@#A survey of natural vegetation and soil of Nikyal valley was undertaken. Phytosociological survey was conducted by using Braun-Blanquet's approach. The study also investigated the vegetation structure and its relationship with altitude and edaphic factors. The floristic data was analyzed by cluster anlaysis, detrended correspondence analysis and canonical correspondence analysis using CANACOO 5.0.@*RESULTS@#A total of 110 plant species and 13 stands were merged into five major associations as dema rcated by cluster analysis and detrended correspondence analysis. The associations were Olea-Pinus-Themeda association, Myrsine-Rhus-Quercus association, Quercus-Rubus-Pinus association and Quercus association. Soil organic matter, saturation, pH and altitude play the major role in distribution of species.@*CONCLUSIONS@#The variation in vegetation structure is controlled by the altitudinal gradient and physiochemical properties of soil. These results indicate a deteriorated forest structure and reduced regeneration pattern, demanding immediate attention of forest management authorities.

6.
J Environ Biol ; 2013 Jan; 34(1): 107-111
Article in English | IMSEAR | ID: sea-148498

ABSTRACT

The composition and seasonal variation of the algal turf of Lake Ladik were studied using samples collected from one station between June 2000 and May 2001. 50 taxa of diatoms were identified in the epiphyton. Navicula veneta, N. halophila, Nitzschia fonticola and Aulacoseira distans were particularly important on turf community. During the October month several Navicula species become progressively more important. Gomphonema lateripunctatum was particularly notable. Other diatoms were occasionally abundant, including Cymbella affinis, C. silesiaca, Navicula cryptocephala, Gomphonema olivaceum and Cyclotella ocellata. Also Navicula lanceolata and Anomoeoneis brachysira were conspicuous, owing to their large size, but were never numerically abundant. Fragilaria ulna and Nitzschia palea were found in low numbers in study area and this pointed out there has not been a remarkable abundance of algal pollution in Lake Ladik. The associations between July and August with bonds to June, January and February with bonds to April were most significant in the study period obtained by cluster analysis. Shannon diversity and evenness presented small variations during the study period. Lake Ladik presented low values of species richness particularly during summer period and highest values were recorded in April. According to canonical correspondence analysis, there was association between some Navicula and Nitzschia species with PO4-, NH3-N. Also the multivariate analysis showed, temperature as the most important factor in the distribution and abundance of diatoms on turf biomass.

7.
J Environ Biol ; 2012 Nov; 33(6): 1115-1125
Article in English | IMSEAR | ID: sea-148480

ABSTRACT

An investigation was carried out during June 2005 to May 2007 on hydrography, composition and community structure of phytoplankton including chlorophyll a in Parangipettai coastal waters (southeast coast of India). Air and surface water temperatures varied from 25.5 to 31.2 °C and from 25 to 29.3°C, respectively. Salinity values varied from 5 to 33.1‰ and the pH ranged between 7.2 and 8.3. Dissolved oxygen content varied from 3.1 to 7.9 mg l-1 while the light extinction coefficient values (LEC) ranged between 1.8 and 11.0 cm. The range of inorganic nutrients viz., nitrate, nitrite, phosphate and silicate were: 6.5 - 27.0 µM; 1.0 - 8.9 µM; 0.1 - 3.0 µM and 15.0 - 140 µM, respectively. The range of chlorophyll a was: 2.0 - 7.5 µg l-1. Presently, 117 phytoplankton species representing different classes viz: Bacillariophyceae (66); Dinophyceae (22); Cyanophyceae (19); Chlorophyceae (7) and Chrysophyceae (3) were recorded. The phytoplankton cell abundance varied from 0.14 to 132 cells ml-1, with peak diversity (3.52 bits ind.-1) during summer season. The maximum abundance was found during summer season coinciding with the stable hydrographical conditions. Canonical Correspondence Analysis was applied in this study for discriminating environmental factors effecting on phytoplankton community at species level.

8.
Rev. biol. trop ; 56(3): 1557-1569, sep. 2008. graf, tab
Article in English | LILACS | ID: lil-637883

ABSTRACT

The floristic variations of shrub and tree components were studied in two sites of Semideciduous Forest, initial forest and mature forest, located in the Mata do Paraíso Forest Reserve, in Viçosa, State of Minas Gerais, Southeastern Brazil, in order to analyze the floristic similarity and the correlations between environmental variables and the distribution of tree species in these forests. Individual trees with a diameter at breast height (DBH) ≥ 4.8 cm were sampled in twenty 10 x 30 m plots (10 plots in each site). The plots were distributed systematically at 10 m intervals. The environmental variables analyzed were: the canopy openness and soil chemical and texture characteristics. The two forest sites showed clear differences in the levels of canopy openness and soil fertility, factors that reflect the floristic and successional differences of the shrub and tree component, revealed by the low similarity between these forests by cluster analysis. The canonical correspondence analysis (CCA) of environmental variables and species abundance indicated that the species in these forests studied are distributed under strong influence of canopy openness, moisture and soil fertility. Rev. Biol. Trop. 56 (3): 15571569. Epub 2008 September 30.


Estudiamos las variaciones florísticas de arbustos y árboles en dos sitios de un bosque semicaducifolio, bosque primario y bosque maduro, en la Reserva Forestal Mata do Paraíso, en Viçosa, Estado de Minas Gerais, Sudeste de Brasil, para analizar la similitud florística y las correlaciones entre las variables ambientales y la distribución de tres especies en estos bosques. Árboles individuales con diámetro a la altura del pecho (DAP) ≥ 4.8 cm. fueron muestreados en veinte parcelas de 10 x 30 m (10 parcelas en cada sitio). Las parcelas se distribuyeron sistemáticamente a intervalos de 10 m. Las variables ambientales fueron analizadas así: la abertura del dosel y características químicas y de textura del suelo. Los dos sitios de bosque mostraron diferencias evidentes en la abertura del dosel y fertilidad del suelo, factores que reflejan las diferencias florísticas y sucesionales de arbustos y árboles, revelado por la baja similitud entre estos bosques por medio de análisis de conglomerados. El análisis de correspondencia canónica (CCA) de variables ambientales y abundancia de especies indican que las especies en los bosques estudiados están distribuidas bajo una fuerte influencia de la abertura del dosel, humedad y fertilidad del suelo.


Subject(s)
Ecosystem , Trees/classification , Brazil , Conservation of Natural Resources , Humidity , Soil
9.
Rev. biol. trop ; 56(1): 247-256, mar. 2008. graf, tab, ilus
Article in Spanish | LILACS | ID: lil-496377

ABSTRACT

Population structure and environmental relationships of the tropical tree Nectandra rudis (Lauraceae), a rare species in western Mexico. The tree N. rudis is a rare species from western Mexico of which community and population features are unknown. We studied a population in an altitudinal gradient, from 550-1,850 m above sea level in the Sierra de Manantlan, Jalisco, Mexico. We established four 60x48 m sample sites at vertical distances of 100 m along this altitudinal gradient. Within each plot, ten 100 m2 circular sub-sampling units were randomly located. At each unit, we recorded diameter at breast height (dbh) and tree height for all woody vegetation > or =2.5 cm dbh. Basal area, tree density, frequency, species richness and importance values per species and plot. We estimated the vertical structure (total tree height) and diameter( as M=5log(10)N) for all N. rudis individuals. A direct ordination through Canonical Correspondence Analysis was done, involving amongst other species, edaphic and environmental data matrices. The record of 44 N. rudis individuals, in seven out the 56 plots sampled, represents the most septentrional record for the species and the first in Western Mexico. Its density and basal area represented 4.5 % and 8.7 % respectively of the total estimated for the community. The greatest importance values were observed at 1 650 m above sea level. The population structure of N. rudis is structured into five diameter categories in an inverse "J" shaped distribution. This is a typical behavior observed to occur in the Lauraceae, which produces big seeds of short viability that germinate when there is high soil moisture content. The species tend to form dense seedling banks although only a reduced number of them are able to survive. Species richness varies from 27 to 39 at plot level; the greatest importance values for the plots on which N. rudis was found, corresponds to Urera verrucosa (Liebm.) V.W. Steinm., N. rudis, Ficus sp...


Nectandra rudis es una especie rara en el occidente de México. Analizamos la población y la comunidad donde se desarrolla, en la Sierra de Manantlan, Jalisco, México. Establecimos cuatro parcelas de 60x48 m con diferencias altitudinales de 100 m entre sí. En cada una seleccionamos aleatoriamente diez círculos de 100 m2 cada uno, en los cuales medimos los diámetros normales y las alturas de las especies leñosas con diámetro ≥2.5 cm. Para cada especie y por parcela determinamos el área basal, la densidad, la frecuencia, la riqueza de especies y los valores de importancia. Establecimos la estructura vertical y diamétrica de N. rudis. Hicimos una ordenación directa con la matriz de especies y las variables edáficas y ambientales. El registro de N. rudis en la Sierra de Manantlán representa el primer registro para el occidente de México y el más septentrional del taxon. La población se estructura en cinco categorías diamétricas y genera una curva en forma de “J” invertida. La riqueza de especies en las parcelas donde se encuentra N. rudis, varía de 27 a 39, y los mayores valores de importancia son para Urera verrucosa, N. rudis y Ficus sp. La ordenación directa permite postular a la presencia de árboles caídos, la cobertura, la profundidad del horizonte superficial y el magnesio soluble, como los factores ambientales de mayor influencia en la distribución y abundancia de N. rudis.


Subject(s)
Altitude , Ecology , Lauraceae/physiology , Trees , Tropical Climate , Population Density , Population Dynamics , Lauraceae/classification , Mexico
10.
Rev. biol. trop ; 54(2): 657-672, jun. 2006. graf, tab
Article in English | LILACS | ID: lil-492036

ABSTRACT

The bird species distribution along a dry forest-oak woodland vegetation gradient was studied in autumn and spring in two consecutive years. Intra-seasonal comparisons showed that bird species had similar distributions in each of the two years. Inter-seasonal changes were mainly due to compositional differences even though resident species generally used similar habitats in both seasons. Ordination analyses, based on the first year bird species abundances, showed a clearly segregated distribution between forest and woodland birds. Within these two vegetation types, the distribution tended to be more individualistic. Nevertheless further habitats could be identified according to groups of birds having similar distributions. These habitats did not correspond to the plant associations which resulted from a previous classification of the vegetation. Observations of the plant use by the birds during the study period showed that, in most cases, the plant variables associated with ordination analyses are unlikely to be very important for the bird species life cycles.


Se estudió la distribución de especies de aves a lo largo de un gradiente de vegetación bosque seco – bosque de encino en el otoño y primavera de dos años consecutivos. Las comparaciones intra-estacionales mostraron distribuciones similares de las especies de aves en ambos años. Los cambios inter-estacionales se debieron principalmente a diferencias en la composición, aunque las especies residentes normalmente usan hábitats similares en ambas estaciones. Los análisis de ordenación, basados en las abundancias de las aves en el primer año de muestreo, mostraron una distribución claramente segregada entre aves del bosque seco y del bosque de encino. Aunque la distribución de las especies fue más azarosa dentro de cada tipo de vegetación, se pudieron identificar ciertos hábitats en base a grupos de aves con distribuciones similares. Estos hábitats no correspondieron con las asociaciones vegetales identificadas. Las observaciones del uso de las plantas durante el período de estudio sugieren, en la mayoría de los casos, que las variables vegetales asociadas con los ejes de ordenación no serían muy importantes para el ciclo de vida de las especies de aves. Sin embargo, se requiere investigación adicional para comprender su verdadera función.


Subject(s)
Animals , Birds/physiology , Biodiversity , Behavior, Animal/physiology , Ecosystem , Quercus , Trees , Birds/classification , Feeding Behavior/physiology , Conservation of Natural Resources , Population Density , Species Specificity , Seasons , Linear Models , Mexico
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