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71.
Renata B. S. Oliveira Riccardo Mugnai Carolina M. Castro Darcilio F. Baptista 《Environmental monitoring and assessment》2011,175(1-4):75-85
The purpose of this study was to establish a subsampling procedure for benthic macroinvertebrates to aid in the development of a multimetric index to assess the biological condition of streams. Data from six streams that are considered minimally impaired were used. Subsampling was done using a device divided into 24 quadrats. The sediment from each quadrat was sorted, and all organisms were removed and identified. Richness metrics were the most affected by subsample size. Relative-abundance metrics were the most stable, proving that the sample was well distributed throughout the tray and abundance proportions were maintained. The results showed that the macroinvertebrate assemblage present in the six quadrats was similar to that present in the full sample. These analyses indicated that six quadrats, randomly designated, with a minimum of 200 collected specimens could be used in place of the full sample. In routine water management, managing time and costs are a major challenge; therefore, this type of simplification is absolutely necessary to ensure that a biomonitoring tool is useful for practical applications. 相似文献
72.
Gustavo Muniz Dias Luiz Francisco Lembo Duarte Vera Nisaka Solferini 《Marine Biology》2006,148(4):807-815
Pelagic larvae are highly important for maintaining the gene flow among populations of sessile marine invertebrates. Colonial
ascidians consist, exclusively, of brooding species, with lecithotrophic larvae that have a limited dispersal. As a result,
there is a marked differentiation among populations. In this work, we used allozyme electrophoresis to access the genetic
variation in four populations of Symplegma rubra, a colonial ascidian frequently found in the intertidal zone of Southeastern Brazilian coast. High variability was found
at three of the four sites sampled, the exception being Praia Grande in the State of Rio de Janeiro. At this site, there was
a great preponderance of clones, which possibly reflected the enclosed nature of the location and its low water circulation
that reduce the dispersal capabilities of these animals. S. rubra did not conform to expectations for random mating (Hardy–Weinberg equilibrium): there was a deficit of heterozygotes that
was more related to the small population size than to inbreeding processes, since F
is analysis per locus revealed a deficiency of heterozygotes at only one locus—MDH*. The greatest variation in allele frequency was found for GPI-2*. Analyses of genetic variability revealed moderate differentiation among the populations (F
ST=0.051), which was unexpected for a species with a low dispersal capability. Rafting, a frequently underestimated means of
dispersal, may be the main mode of gene flow in this species over large areas, since colonies of S. rubra are frequently seen growing on drift material and there is no evidence that the larva survive for a long time in the plankton. 相似文献
73.
Helton Nonato de Souza Ron G.M. de GoedeLijbert Brussaard Irene M. CardosoEdivania M.G. Duarte Raphael B.A. FernandesLucas C. Gomes Mirjam M. Pulleman 《Agriculture, ecosystems & environment》2012,146(1):179-196
Sustainable production and biodiversity conservation can be mutually supportive in providing multiple ecosystem services to farmers and society. This study aimed to determine the contribution of agroforestry systems, as tested by family farmers in the Brazilian Rainforest region since 1993, to tree biodiversity and evaluated farmers’ criteria for tree species selection. In addition, long-term effects on microclimatic temperature conditions for coffee production and chemical and biological soil characteristics at the field scale were compared to full-sun coffee systems. A floristic inventory of 8 agroforests and 4 reference forest sites identified 231 tree species in total. Seventy-eight percent of the tree species found in agroforests were native. The variation in species composition among agroforests contributed to a greater γ-diversity than α-diversity. Monthly average maximum temperatures were approximately 6 °C higher in full-sun coffee than in agroforests and forests. Total soil organic C, N mineralization and soil microbial activity were higher in forests than in coffee systems, whereas the chemical and biological soil quality in agroforests did not differ significantly from full-sun coffee after 13 years. Given its contribution to the conservation of biodiversity and its capacity to adapt coffee production to future climate change, coffee agroforestry offers a promising strategy for the area. 相似文献
74.
Faria Maria Graciela Iecher Avelino Katielle Vieira Philadelpho Biane Oliveira dos Santos Bomfim Rafaela do Valle Juliana Silveira Júnior Affonso Celso Gonçalves Dragunski Douglas Cardoso de Souza Ferreira Ederlan de Souza Carolina Oliveira Ribeiro Camila Duarte Ferreira Colauto Nelson Barros Linde Giani Andrea 《Environmental science and pollution research international》2022,29(58):87519-87526
Environmental Science and Pollution Research - Lentinus crinitus bioaccumulates lithium in mycelia, but bioaccumulation may be affected by pH of the culture medium. Lithium is used in clinical... 相似文献
75.
Helena Godoy Bergallo Ana Carolina Bergallo Henrique Bergallo Rocha Carlos Frederico Duarte Rocha 《Journal of Coastal Conservation》2016,20(3):191-198
Invasion by alien species is one of the most critical factors affecting global biodiversity, leading to homogenization and species loss worldwide. Jackfruit (Artocarpus heterophyllus Lam., Moraceae) is one of the most conspicuous invasive plants in Brazil. We studied jackfruit invasion in the Atlantic Forest in Ilha Grande State Park, located on an island (Ilha Grande), by assessing jackfruit distribution and density along 23 trails (90 km). Presence or absence was verified in a total of 857 plots. Data showed that jackfruit is spread all over Ilha Grande, and that plant density varied significantly along and between trails. Jackfruit was registered as the dominant tree species on some of the trails. Control by park managers is an urgent need in order to ensure the conservation of local biodiversity. A decision key for jackfruit management according to jackfruit density, age class and slope is provided. 相似文献
76.
Sonia Rodrigues Graham Urquhart Iain Hossack Ma Eduarda Pereira Armando C. Duarte Christine Davidson Andrew Hursthouse Peter Tucker Douglas Roberston 《Environmental Chemistry Letters》2009,7(2):141-148
As part of a harmonised assessment of urban soils (), we investigated the variability of metal content in soils from Aveiro (Portugal) and Glasgow (UK). Samples were collected
from parks and other public open spaces in each city. Metal content (Al, Ca, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and basic soil
parameters (texture, CEC, pH, organic matter) were determined and data investigated using principal component analysis (PCA).
The two cities differ in absolute levels of metal content reflecting industrial and historical development. Factors identified
by PCA included anthropogenic (Cu, Pb, Zn), soil properties and geology, which explain variability when data were assessed
based on metal content, soil properties and land use. This study highlights the contribution from geological background even
in strongly urbanised environments. 相似文献
77.
Anderson Ribeiro Duarte Luiz Duczmal Sabino José Ferreira André Luiz F. Cançado 《Environmental and Ecological Statistics》2010,17(2):203-229
The geographic delineation of irregularly shaped spatial clusters is an ill defined problem. Whenever the spatial scan statistic
is used, some kind of penalty correction needs to be used to avoid clusters’ excessive irregularity and consequent reduction
of power of detection. Geometric compactness and non-connectivity regularity functions have been recently proposed as corrections.
We present a novel internal cohesion regularity function based on the graph topology to penalize the presence of weak links
in candidate clusters. Weak links are defined as relatively unpopulated regions within a cluster, such that their removal
disconnects it. By applying this weak link cohesion function, the most geographically meaningful clusters are sifted through
the immense set of possible irregularly shaped candidate cluster solutions. A multi-objective genetic algorithm (MGA) has
been proposed recently to compute the Pareto-sets of clusters solutions, employing Kulldorff’s spatial scan statistic and
the geometric correction as objective functions. We propose novel MGAs to maximize the spatial scan, the cohesion function
and the geometric function, or combinations of these functions. Numerical tests show that our proposed MGAs has high power
to detect elongated clusters, and present good sensitivity and positive predictive value. The statistical significance of
the clusters in the Pareto-set are estimated through Monte Carlo simulations. Our method distinguishes clearly those geographically
inadequate clusters which are worse from both geometric and internal cohesion viewpoints. Besides, a certain degree of irregularity
of shape is allowed provided that it does not impact internal cohesion. Our method has better power of detection for clusters
satisfying those requirements. We propose a more robust definition of spatial cluster using these concepts. 相似文献
78.
Aver Gustavo Francisco Espín Silvia Dal Corno Renata De Boni García-Fernández Antonio Juan Petry Maria Virginia 《Environmental science and pollution research international》2020,27(6):5971-5980
Environmental Science and Pollution Research - In this study, we determined the presence of organochlorine pesticides (OCPs) in back feathers from three raptor species, Phalcoboenus chimango,... 相似文献
79.
Khalik M. Sabil Ana Rita C. Duarte John Zevenbergen Murni M. Ahmad Suzana Yusup Abdul A. Omar Cor J. Peters 《International Journal of Greenhouse Gas Control》2010,4(5):798-805
A laboratory-scale reactor system is built and operated to measure the kinetic of formation for single and mixed carbon dioxide–tetrahydrofuran hydrates. The T-cycle method, which is used to collect the kinetic data, is briefly discussed. For single carbon dioxide hydrate, the induction time decreases with the increase of the initial carbon dioxide pressure up to 2.96 MPa. Beyond this pressure, the induction time is becoming relatively constant with the increase of initial carbon dioxide pressure indicating that the liquid phase is completely supersaturated with carbon dioxide. Experimental results show that the inclusion of tetrahydrofuran reduces the induction time required for hydrate formation. These observations indicate hydrate nucleation process and onset growth are more readily to occur in the presence of tetrahydrofuran. In contrast, the presence of sodium chloride prolongs the induction time due to clustering of water molecules with the ions and the salting-out effects. It is also shown that the degree of subcooling required for hydrate formation is affected by the presence of tetrahydrofuran and sodium chloride in the hydrate forming system. The presence of tetrahydrofuran in the hydrate system significantly reduces the amount of carbon dioxide uptake. The apparent rate constant, k, for those systems are reported. 相似文献
80.
Teresa Rocha-Santos Filipe Ferreira Lurdes Silva Ana Cristina Freitas Ruth Pereira Mário Diniz Luísa Castro Isabel Peres Armando Costa Duarte 《Environmental science and pollution research international》2010,17(4):866-874