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91.
Margarida Cardoso da Silva António Carmona Rodrigues 《Journal of Coastal Conservation》2004,10(1):13-24
The need for a better management of estuaries requires an environmental characterization following a methodology that allows
the comparison of distinct estuarine systems and the assessment of their evolution. The peculiar characteristics of estuaries,
in particular their intrinsic variability, make this characterization difficult and there is no commonly accepted general
methodology available. The approach followed in freshwater ecosystems is generally based on the concept of environmental indicators,
but such a concept has not been developed for estuaries. Indeed, a different approach is needed here, due to the spatial heterogeneity
and the different time scales associated with the processes that control water quality.
This paper presents a proposal for a methodology that starts with observed values and uses a procedure to integrate these
values in time and space in order to calculatesignificant values, upon whichnormalized indicators are built which take into account criteria based either on legal, scientific or heuristic concentration limits. A normalization
is carried out in two steps: (1) application of a mathematical operator to theignificant values, (2) transformation using the concept ofpenalty curves. This methodology may be complemented with the definition ofquality classes, particularly appealing and useful, as tools to communicate with decision makers and the public in general.
Water quality data pertaining to the Tejo estuary are used to test the methodology. 相似文献
92.
Caesalpinia echinata (brazilwood or Pernambuco wood) comprises a complex of three morphological leaf variants, characterized by differences in
the number and size of the pinnae and leaflets, and occurring in allopatric and sympatric populations. The present study evaluates
the utility of the chloroplast DNA trnL intron in a phylogenetic analysis of the three leaf variants along with other species of Caesalpinia and generic relatives. Our study supports the hypothesis that the name C. echinata designates a species complex and provides evidence that one of the forms, the highly divergent C. echinata large-leafleted variant, represents a distinct taxon. 相似文献
93.
Samira Veiga Ravaiano Wagner Faria Barbosa Lúcio Antônio Campos Gustavo Ferreira Martins 《Die Naturwissenschaften》2018,105(7-8):48
The insect immune system faces various challenges; particularly in social bees, caste system and age polyethism expose individuals to numerous environmental and working conditions. However, little is known about how cellular defenses in social bees may be organized to respond to a variety of immune challenges. Here, we describe the morphological features and the total and differential counts of hemocytes in different female classes (newly emerged workers, nurses, foragers, and virgin queens) of the eusocial stingless bee Melipona quadrifasciata. Granulocytes and prohemocytes were, respectively, the most and the least abundant cells among all classes of females. Furthermore, there were more prohemocytes in virgin queens than in foragers. The total number of hemocytes was smaller in foragers, whereas the largest number was observed in nurse workers. This reduced amount of hemocytes in foragers might allow energy savings to perform colony activities such as foraging and defense. Foragers also had the biggest hemocytes (either prohemocytes, granulocytes, or plasmatocytes) in comparison to the other classes of females, which might have arisen as a compensation for the reduction in number of these cells during aging. These results suggest that profiles of hemocytes of M. quadrifasciata vary according to the caste and age of this eusocial bee. 相似文献
94.
Popin Gustavo V. Santos Arthur K. B. Oliveira Thiago de P. de Camargo Plínio B. Cerri Carlos E. P. Siqueira-Neto Marcos 《Mitigation and Adaptation Strategies for Global Change》2020,25(4):559-577
Mitigation and Adaptation Strategies for Global Change - Global warming can intensify the soil organic matter (SOM) turnover, damaging soil health. Crop residues left on the soil are important to... 相似文献
95.
Rodolfo Jaffé Fabiana C. Pioker-Hara Charles F. dos Santos Leandro R. Santiago Denise A. Alves Astrid de M. P. Kleinert Tiago M. Francoy Maria C. Arias Vera L. Imperatriz-Fonseca 《Die Naturwissenschaften》2014,101(3):261-264
High genetic diversity is important for the functioning of large insect societies. Across the social Hymenoptera (ants, bees, and wasps), species with the largest colonies tend to have a high colony-level genetic diversity resulting from multiple queens (polygyny) or queens that mate with multiple males (polyandry). Here we studied the genetic structure of Trigona spinipes, a stingless bee species with colonies an order of magnitude larger than those of polyandrous honeybees. Genotypes of adult workers and pupae from 43 nests distributed across three Brazilian biomes showed that T. spinipes colonies are usually headed by one singly mated queen. Apart from revealing a notable exception from the general incidence of high genetic diversity in large insect societies, our results reinforce previous findings suggesting the absence of polyandry in stingless bees and provide evidence against the sperm limitation hypothesis for the evolution of polyandry. Stingless bee species with large colonies, such as T. spinipes, thus seem promising study models to unravel alternative mechanisms to increase genetic diversity within colonies or understand the adaptive value of low genetic diversity in large insect societies. 相似文献
96.
97.
Maria Cléa Brito de Figueirêdo Geraldo Stachetti Rodrigues Armando Caldeira-Pires Morsyleide de Freitas Rosa Fernando Antônio Sousa de Aragão Vicente de Paulo Pereira Barbosa Vieira Francisco Suetônio Bastos Mota 《Journal of Cleaner Production》2010,18(14):1366-1375
As sustainability considerations increasingly dominate the technology development debate worldwide, practical approaches to assess environmental performance of innovations have been warranted. The present study (Part 1) introduces Ambitec-Life Cycle, a method derived from Ambitec-Agro for considering life cycle thinking in the environmental performance evaluation (EPE) of agro-industrial innovations. An agro-industrial innovation case study related to residue recycling is presented, revealing steps in the product life cycle where opportunities are best for technological improvements. In Part 2 (this issue) of this study, a methodological approach for considering the environmental vulnerability of watersheds and to integrate this analysis in EPE methods is presented. This approach is applied to Ambitec-Life Cycle and to the same residue case study, allowing the identification of performance indicators with greater potential to cause impacts at the studied watersheds. 相似文献
98.
Fernanda F. Heleno Maria Eliana L. R. de Queiroz Antônio Augusto Neves Romenique S. Freitas Lêda Rita A. Faroni André Fernando De Oliveira 《Journal of environmental science and health. Part. B》2013,48(2):94-101
The effect of ozone fumigation on the reduction of difenoconazole residue on strawberries was studied. Strawberries were immersed in 1.0 L of aqueous solution containing 400 μL of the commercial product (250 g L?1 of difenoconazole) for 1 min. Then, they were dried and exposed to ozone gas (O3) at concentrations of 0.3, 0.6 and 0.8 mg L?1 for 1 h. The ozone fumigation treatments reduced the difenoconazole residue on strawberries to concentrations below 0.5 mg kg?1, which corresponds to a 95% reduction. The strawberries treated with ozone and the control group, which was not treated with ozone, were stored at 4°C for 10 days. Some characteristics of the fruit were monitored throughout this period. Among these, pH, weight loss and total color difference did not change significantly (P > 0.05). The fumigation with ozone significantly affected the soluble solids, titratable acidity and ascorbic acid content (vitamin C) of the strawberries preventing a sharp reduction of these parameters during storage. 相似文献
99.
dos Santos Filho Edson Antônio Siqueira Danilo Diniz Araújo Edcleide Maria Luna Carlos Bruno Barreto de Medeiros Everaldo Paulo 《Journal of Polymers and the Environment》2022,30(2):443-460
Journal of Polymers and the Environment - Nowadays, there is a need to obtain eco-friendly materials, especially plastics that are responsible for most of the environmental pollution. In this... 相似文献
100.
Teodoro Filipe Simões Soares Liliane Catone Filgueiras Jefferson Gonçalves de Azevedo Eduardo Ribeiro Patiño-Agudelo Álvaro Javier Adarme Oscar Fernando Herrera da Silva Luis Henrique Mendes Gurgel Leandro Vinícius Alves 《Environmental science and pollution research international》2022,29(18):26425-26448
Environmental Science and Pollution Research - A new one-pot synthesis method optimized by a 23 experimental design was developed to prepare a biosorbent, sugarcane bagasse cellulose succinate... 相似文献