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181.
Leite Luan de Souza Ogura Allan Pretti dos Santos Danilo Vitorino Espíndola Evaldo Luiz Gaeta Daniel Luiz Antonio 《Environmental science and pollution research international》2022,29(24):35800-35810
Environmental Science and Pollution Research - Algal organic matter (AOM) in water reservoirs is a worldwide concern for drinking water treatment; once it is one of the main precursors for... 相似文献
182.
Moretto Cristiane Castellane Tereza Cristina Luque Leonel Tatiane Fernanda Campanharo Joao Carlos de Macedo Lemos Eliana Gertrudes 《Environmental science and pollution research international》2022,29(31):46953-46967
Environmental Science and Pollution Research - Rhizosphere bacteria, for example, rhizobia, can play several roles, and one of the most important, the protection of plant roots against toxic... 相似文献
183.
Invisible floral larcenies: microbial communities degrade floral nectar of bumble bee-pollinated plants 总被引:2,自引:0,他引:2
The ecology of nectarivorous microbial communities remains virtually unknown, which precludes elucidating whether these organisms play some role in plant-pollinator mutualisms beyond minor commensalism. We simultaneously assessed microbial abundance and nectar composition at the individual nectary level in flowers of three southern Spanish bumble bee-pollinated plants (Helleborus foetidus, Aquilegia vulgaris, and Aquilegia pyrenaica cazorlensis). Yeasts were frequent and abundant in nectar of all species, and variation in yeast density was correlated with drastic changes in nectar sugar concentration and composition. Yeast communities built up in nectar from early to late floral stages, at which time all nectaries contained yeasts, often at densities between 10(4) and 10(5) cells/mm3. Total sugar concentration and percentage sucrose declined, and percentage fructose increased, with increasing density of yeast cells in nectar. Among-nectary variation in microbial density accounted for 65% (H. foetidus and A. vulgaris) and 35% (A. p. cazorlensis) of intraspecific variance in nectar sugar composition, and 60% (H. foetidus) and 38% (A. vulgaris) of variance in nectar concentration. Our results provide compelling evidence that nectar microbial communities can have detrimental effects on plants and/or pollinators via extensive nectar degradation and also call for a more careful interpretation of nectar traits in the future, if uncontrolled for yeasts. 相似文献
184.
Francisco Leitão Miguel N. Santos Karim Erzini Carlos Costa Monteiro 《Marine Biology》2008,153(6):1233-1244
There is a concern that artificial reefs (AR) may act purely as fishing aggregation devices. Predators attracted to ARs can
influence the distribution and abundance of prey fish species. Determining the role of predators in AR is important in advancing
the understanding of community interactions. This paper documents the effects of predation on fish assemblages of AR located
near a coastal lagoon fish nursery. The Dicentrarchus labrax is a very opportunistic species preying on juveniles (0+ and 1+ age classes) of several demersal fish species on the ARs. Reef prey and sea bass abundance were negatively correlated. The
mean numbers of prey per sea bass stomach increased with the increase of reef fish prey abundance, suggesting that predation
has a significant influence, resulting in a decrease in prey abundance. Prey mortality (4–48%) of demersal reef fish associated
species depends on bass density. Prey selection was related both with prey abundance and vulnerability. Results showed that
D. labrax predation on AR-fish associated species can increase prey natural mortality. However, the role of bass predation on the ecological
functioning of exploited ARs is not clear. There may be increases in local fishing yields due either to an increase in predator
biomass through aggregation of sea bass attracted to ARs or to greater production. In contrast, predation on juveniles of
economically important reef fish preys, especially the most frequent and abundant (Boops boops), can contribute to a decrease in recruitment to the fishery. Our results indicate that inter-specific interactions (predator–prey)
are important in terms of conservation and management, as well as for the evaluation of the long-term effects of reef deployment.
Thus, it is necessary to consider ecological interactions, such as predation, prior to the development and deployment of artificial
habitats as a tool for rehabilitation. 相似文献
185.
We give reasons why demographic parameters such as survival and reproduction rates are often modelled well in stochastic population simulation using beta distributions. In practice, it is frequently expected that these parameters will be correlated, for example with survival rates for all age classes tending to be high or low in the same year. We therefore discuss a method for producing correlated beta random variables by transforming correlated normal random variables, and show how it can be applied in practice by means of a simple example. We also note how the same approach can be used to produce correlated uniform, triangular, and exponential random variables. 相似文献
186.
Citrus Sudden Death (CSD) is a disease that has affected sweet orange trees grafted on Rangpur lime in the south of Minas Gerais state and in the north of São Paulo state (Brazil). This is a worrying characteristic because the Rangpur lime responds to 85% of the Brazilian citrus rootstocks. This disease is believed to be caused by a virus transmitted by aphids (vector) of the citrus. In this work, we have adopted the Cellular Automata model (CA) to study the temporal evolution of the disease. We take into account the effect of the wind in the space covered by the aphid. To establish the relationship between the space covered by the aphid and the intensity of the wind, we have adopted the rule-based fuzzy system. Simulations were performed and compared to real data. Through the use of the mean absolute error (MAE) method, it was possible to verify a 70% of similarity between our model of data and the real one. 相似文献
187.
Carlos César Martínez-Rivera H. Carl Gerhardt 《Behavioral ecology and sociobiology》2008,63(2):195-208
Senders and receivers influence dynamic characteristics of the signals used for mate attraction over different time scales.
On a moment-to-moment basis, interactions among senders competing for a mate influence dynamic characteristics, whereas the
preferences of receivers of the opposite gender exert an influence over evolutionary time. We observed and recorded the calling
patterns of the bird-voiced treefrog Hyla avivoca to assess how the dynamic characters of calls vary during interactions among groups of males in a chorus. This question was
also addressed using playback experiments with males. Playback experiments with females showed how changes in dynamic call
properties are likely to affect male mating success. Frogs calling in pairs, groups, or in response to playbacks produced
longer calls than did isolated males. During call overlap, males often increased the duration of the silent interval (gaps)
between the pulses of their calls so that the pulses of the calls of two neighbors interdigitated. This change resulted in
increased variability of pulse rate, a traditionally static acoustic property; however, males also produced high proportions
of non-overlapped calls in which variability in pulse rate was low and had species-typical values. Females preferred long
calls to short- and average-duration calls, and non-overlapped calls to overlapped calls. Given a choice between pairs of
overlapped calls, females preferred pairs in which the proportion of overlap was low and pairs in which the pulses of such
calls interdigitated completely. The observed patterns of vocal competition thus reflect the preferences of conspecific females,
which have influenced the evolution of the calling behavior of H. avivoca.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
188.
Emilio Chuvieco Sergio Opazo Walter Sione Hector Del Valle Jesús Anaya Carlos Di Bella Isabel Cruz Lilia Manzo Gerardo López Nicolas Mari Federico González-Alonso Fabiano Morelli Alberto Setzer Ivan Csiszar Jon Ander Kanpandegi Aitor Bastarrika Renata Libonati 《Ecological applications》2008,18(1):64-79
This paper presents results of the AQL2004 project, which has been develope within the GOFC-GOLD Latin American network of remote sensing and forest fires (RedLatif). The project intended to obtain monthly burned-land maps of the entire region, from Mexico to Patagonia, using MODIS (moderate-resolution imaging spectroradiometer) reflectance data. The project has been organized in three different phases: acquisition and preprocessing of satellite data; discrimination of burned pixels; and validation of results. In the first phase, input data consisting of 32-day composites of MODIS 500-m reflectance data generated by the Global Land Cover Facility (GLCF) of the University of Maryland (College Park, Maryland, U.S.A.) were collected and processed. The discrimination of burned areas was addressed in two steps: searching for "burned core" pixels using postfire spectral indices and multitemporal change detection and mapping of burned scars using contextual techniques. The validation phase was based on visual analysis of Landsat and CBERS (China-Brazil Earth Resources Satellite) images. Validation of the burned-land category showed an agreement ranging from 30% to 60%, depending on the ecosystem and vegetation species present. The total burned area for the entire year was estimated to be 153 215 km2. The most affected countries in relation to their territory were Cuba, Colombia, Bolivia, and Venezuela. Burned areas were found in most land covers; herbaceous vegetation (savannas and grasslands) presented the highest proportions of burned area, while perennial forest had the lowest proportions. The importance of croplands in the total burned area should be taken with reserve, since this cover presented the highest commission errors. The importance of generating systematic products of burned land areas for different ecological processes is emphasized. 相似文献
189.
Carlos A. Grande Alírio E. Rodrigues 《International Journal of Greenhouse Gas Control》2008,2(2):194-202
One of the most important sources of CO2 emissions are the fossil-fuel fired plants for production of electricity. Removal of CO2 from flue gas streams for further sequestration has been proposed by the International Panel on Climate Change experts as one of the most reliable solutions to mitigate anthropogenic greenhouse emissions. When natural gas is employed as fuel, the molar fraction of CO2 in the flue gas is lower than 5% causing serious problems for capture. The purpose of this work is to present experimental validation of an Electric Swing Adsorption (ESA) technology that may be employed for carbon capture for low molar fractions of CO2 in the flue gas streams. To improve energy utilization, an activated carbon honeycomb monolith with low electrical resistivity was employed as selective adsorbent. A mathematical model for this honeycomb is proposed as well as different ESA cycles for CO2 capture. 相似文献
190.
da Silva LI de Souza Sarkis JE Zotin FM Carneiro MC Neto AA da Silva Ados S Cardoso MJ Monteiro MI 《Chemosphere》2008,71(4):677-684
In this work, 24-h PM10 samples were collected in Rio de Janeiro, Brazil, and analysed for trace elements (Cd, Ce, Cu, La, Mo, Ni, Pb, Pd, Rh, Sb and Sn). The sampling was carried out at five locations (Bonsucesso; Centro, downtown city; Copacabana; Nova Igua?u and Sumaré) with different traffic densities and anthropogenic activities. An analytical method based on the EPA method for the determination of trace elements in airborne particulate matter (PM), using ultrasonic-assisted extraction and inductively coupled plasma mass spectrometry (ICP-MS) was applied. Our results suggest that vehicular traffic is the most important source of environmental pollution at the studied sites. The presence of Mo, Pd and Rh in the analysed filters reflects an additional source of pollution caused by the erosion and deterioration of automotive catalytic converters. 相似文献