Metodologia de implantação da construção enxuta: estudo de caso em construtora de porte médio

In recent years, the Brazilian construction industry has gone by changes like currency stability, increasing competition, shortage of skilled labor and increasing quality importance required by the customer, who made the sector companies seek solutions through new management practices in order to become more efficient. A alternative to these management practices is known as Lean Construction which is derived from the Toyota System Production. Lean Construction main goals are to reduce parts of activities that do not add value, increase product value by considering customer needs, reduce variability and production cycle time, simplify process by reducing the number of parts or steps, increase the flexibility in the product execution and transparency process, focus the control on overall process, introduce continuous improvement process, maintain a balance between improvements in flows and conversions and seek to learn from practices adopted by competitors. However, the construction industry is characterized by having nomadic activity, which undertakes an unique product with high cost of production and big inertia for behavioral change, making it difficult to implement the philosophy of lean construction in companies. In this sense, the main objective of this study is to develop a methodology for implementation of the principles of Lean Construction. The method of implementing the proposed management system was designed with the aid of 5W2H tool, and the implementation process is divided into three phases. The first one aims to know in a macro way the current operation of construction, identify who is its target audience and what are the products and services offered to the Market. The second phase aims to describe what actions should be taken and which documents are needed to be created or modified; finally, the third step goal consists in how to control and monitor established processes, where through Strategic Planning the company goals would be set along with their respective targets and indicators in order to keep the system working, aiming for continuous improvement with focus on the customer. This methodology was conceived as a case study analyzing a medium size construction with more than 18 years of activity and certified for almost 10 years with ISO9001 and level A in PBQP-H. We also conclude that this implementation process can be used in any developer and / or builder

A Produção mais Limpa como ferramenta em busca da sustentabilidade empresarial: um estudo de múltiplos casos em empresas do Estado do Rio Grande do Norte

This study aimed to assess the Cleaner Production CP as corporate sustainable tool, through the multiple case studies within companies from Rio Grande do Norte State. In order to achieve this goal a research methodology approach was set. The initial stage of the research methodology was based on a literature review on which it was observed that the CP can be linked with corporate sustainable once it prevents pollution and reduces the operational risks among employees, community and environment. In addition, CP can useful for companies position within competitive position as well as being applied to process, products and services. In order to observe these factors, CP was used within food industry (Company 1), textile industry (Company 2) and in a car dealer (Company 3). Regarding the results, Company 1 changed its raw material as well as implementing housekeeping (control use of water, energy and condensed milk). In Company 2, it was observed the three levels of CP. In other words, housekeeping (e.g. cutting process and manipulation of chemical products), changing technology (high pressure washing machine) and internal and external recycling. In addition, Company 3 considered only level 3 external recycling. As consequence, it was observed that can be applied either within industry as well as service sector. Unfortunately, it was not possible to observe any social gains on a monetary basis. This is due to limitations of the CP methodology and study complexity. Therefore, it was observed improvements regarding to social, environmental and economic areas. Nevertheless, it is necessary more commitment from top level management in order to consider CP like effective sustainable tool

Método de avaliação do gerenciamento de resíduos em canteiro de obras da construção civil : proposta baseada em empresas construtoras da cidade de Natal-RN

According to great concern between the developed industrial activities and resultant impacts over the environment, an association of several factors have occurred, procedures to the efficient management of the rotation between economical development and the environment have been improved. A research in field have been realized inside building sites of companies in order to provide knowledge about the implemented and accomplish actions according to the resolution from CONAMA nº307. Trough the interview among the representations of the companies and photographic survey in loco, such as, what makes the companies implement this management, reutilization and recycling, transport and disposition. The present study had as objective: analyze the insertion of the used tools to residuals management, proposing improvements, in a way that it can be easily identified during the procedures execution in the building sites of the building companies of the city of Natal/RN. To reach the goal, in the first place a revision of the pertinent literature was performed; there for, it can be seen the relation between residues management and environment sustainability, once it happens in a continued way it may prevent the waste and reduces the risk that the activities way bring to the employees, community and environment; once found the great difficult faced with regard to labors, material, equipment, project, planning, costumer s interference, furnisher. And still, it could be verified wich materials generate greater indexes of residues in the works and the main occurrences of waste and loss. However a greater transparency is needed coming from the high administration in the commitment with the continued actions, to make it so, there must be a cultural change inside the company. There for there will be a greater productivity and quality of the under taking such as costumer s satisfaction

Análise de critérios de decisão em estratégia de arranjos produtivos locais: um estudo aplicando o processo de hierarquia analítica (AHP) no setor de cerâmica

This master thesis has the objective of investigating the strategic decision criteria of participants of Local Production Arrangements (LPA) in Brazil. The LPA s are an initiative of support agents to enterprises with the purpose of organizing joint actions for the development of groups (clusters) of enterprises. The choice of the actions is a decision of the participating enterprises and this paper aims at applying a Multi-criteria Analysis Method to analyze the criteria of entrepreneurs that are participating of a LPA. The used method is the Process of Analytical Hierarchy (PAH) and an application is presented along with questionnaires to participants of a ceramic LPA in the northeast of Brazil. The main results show that, in first place, from the implicit strategy of each enterprise there is only one objective for the LPA group and so, at the beginning, an action decided by all of them tends to favor some more than others. In second place, it was observed that there are general inconsistencies between the strategic objectives and the importance as to criteria, even though there have been cases of coherency. As the main conclusion it is pointed that the use of Methods of MCDA is useful to improve the decision making process and to bring more transparency to the logic of the found results

Eutrofização do Reservatório Cruzeta na bacia representativa do rio Seridó RN

Eutrophication has been listed as one of the main problems of water pollution on a global level. In the Brazilian semi-arid areas this problem takes even greater proportions due to characteristical water scarcity of the region. It is extremely important to the predictive eutrophication models development and to the reservoirs management in the semi-arid region, studies that promotes understanding of the mechanisms responsible for the expansion and control of algae blooms, essential for improving the water quality of these environments. The present study had as its main aims, evaluate the temporal pattern of trophic state, considering the influence of nutrients (N and P) and the light availability in the water column in the development of phytoplankton biomass, and perform the mathematical modelling of changes in phosphorus and chlorophyll a concentrations in the Cruzeta man-made lake located on Seridó, a typical semi-arid region of Rio Grande do Norte. To this, a fortnightly monitoring was performed in the reservoir in 05 stations over the months of March 2007 to May 2008. Were measured the concentrations of total phosphorus, total organic nitrogen, chlorophyll a, total, fixed and volatile suspended solids, as well as the measure of transparency (Secchi) and the profiles of photosynthetic active radiation (PAR), temperature, pH, dissolved oxygen and electrical conductivity in the water column. Measurements of vertical profiles have shown some periods of chemical and thermal stratification, especially in the rainy season, due to increased water column depth, however, the reservoir can be classified as warm polimitic. During the study period the reservoir was characterized as eutrophic considering the concentrations of phosphorus and most of the time as mesotrophic, based on the concentrations of chlorophyll a, according to the Thornton & Rast (1993) classification. The N:P relations suggest N limitation, conversely, significant linear relationship between the algae biomass and nutrients (N and P) were not observed in our study. However, a relevant event was the negative and significant correlation presented by Kt and chlorophyll a (r ² = 0.83) at the end of the drought of 2007 and the rainy season of 2008, and the algal biomass collapse observed at the end of the drought season (Dec/07). The equation used to simulate the change in the total phosphorus was not satisfactory, being necessary inclusion of parameters able to increase the power of the model prediction. The chlorophyll a simulation presented a good adjustment trend, however there is a need to check the calibrated model parameters and subsequent equation validation

Desenvolvimento e implantação de um sistema de gestão de pedidos de informação endereçados à Universidade Federal do Rio Grande do Norte a partir do serviço de informações ao cidadão (E-SIC)

Among the numerous policy changes that the world has experienced in recent years, occupies a prominent place in the quest for greater transparency of public agencies. Transparency has been an important tool in the accountability of the State to promote greater participation of the society by providing information that was previously restricted knowledge of public agencies. Brazil, following this trend, promulgated in May 2012 the Access to Information Act that seeks to disclose the actions of the State at all levels, in all public administration agencies. On the same day of the enactment of the law is provided society with a site that is empowering citizens to make their requests for information to government agencies. The Federal University of Rio Grande do Norte, which at that time had no a tool to assist them in managing this demand. This project has the objective to describe, build and implement a solution to solve this problem using Design Science Research as methodology. As result, the solution built in this research became a new module of the institution s ERP became it capable to control the entire process, and will be helpful to others partners which use our system ERP

Violência Sexual Infanto-Juvenil em Natal: uma avaliação do Programa Sentinela

Analyze the problem of sexual violence suffered by children and adolescents in the city of Natal / Rio Grande do Norte (RN), attended by the Programa Sentinela, a service aimed at combating sexual violence children and teenagers who serves on the council of Natal. Thus aims to review the implementation of the Programa Sentinela in Natal / RN, in the period 2001 to 2006, verifying that the program has contributed to the access of children and adolescents who are victims of abuse and sexual exploitation to fundamental rights under the Statute Children and adolescents (ECA) and the Local Plan and the National gainst Infanto-Youth Sexual Violence. It has a theoretical and methodological approach quantitative and qualitative, covering the issue of sexual violence against children and adolescents, as one of the expressions of economic relationships, gender, race and culture that make up the material and symbolic structure of society. It methodological procedure: review of literature on the subject and conducting interviews with professionals and families of children and adolescent victims of sexual violence. Investigate as the unit of analysis the Sentinel Program. The analysis on the governmental actions of this period on this social problem points to the continuity and little change in the care of victims of sexual violence: despite maintain features and palliative assistencialistas, favoring the "Network of Sexual Tourism", go through some innovations in terms of securing rights from the ECA, which is the need for transparency and democratization in the management of government policies. In research undertaken, Brazil will only be combating this type of crime when each of the social actors are actually doing their share, down taboos, facing corruption and strengthening a system of guarantee of rights, which target children and adolescents are unprotected, and often ignored by Brazilian society

O financiamento da política de assistência social no contexto do SUAS: tendências e particularidades do município do Natal-RN

This dissertation analyzes the configuration of the financing of Social assistance in the municipality of Natal-RN in the context of their particular expressions of the problematizando municipal budget against neoliberal adjustment macroeconomic policy. The current trends of "disclaimer" and "desfinanciamento" of social protection by the State, in the context of contemporary capitalism, bring strong implications for Social Security, especially through the redirection of public resources to the international capital, which highlights the overlapping economic interests on social needs. Whereas the changes and innovations occurring in connection with the financing of Social assistance policy, the goal of this documentary research is to identify the characteristics and trends of funding this policy in Natal-RN, from the secondary data analysis from the City of Natal, the Ministry of Social development and hunger and Portal of transparency. In the light of the theoretical, research now presented, shows trends of investment in Social assistance in the municipality of Natal-RN, in the period 2005 to 2009, which are: the tiny role membership (08) Social assistance in the municipal budget; the dispersion and fragmentation of the resources of Social assistance in other organs and/or secretariats of municipal administration; the participation of just 47.5% in expenditure from own organ Manager; the low percentage of implementation of resources foreseen in the Annual Budget Laws; the low allocation of resources in Municipal Social Assistance Fund (FUMAS), which contradicts the national policy for Social Assistance-PNAS/2004; and the predominance of government transfers in the composition of the resources of Social assistance in the municipality. The results of this research suggest that the process of financing of Social assistance in Natal is distant from the principles and guidelines pointed by PNAS/2004. In addition to the effort to understand the complexity of the financing of Social assistance in Natal, this work seeks to contribute to a political analysis in the direction of strengthening social control and the struggle for the expansion of investment in social spending

AO-OIL: um middleware orientado a aspectos baseado em uma arquitetura de referência

Middleware platforms have been widely used as an underlying infrastructure to the development of distributed applications. They provide distribution and heterogeneity transparency and a set of services that ease the construction of distributed applications. Nowadays, the middlewares accommodate an increasing variety of requirements to satisfy distinct application domains. This broad range of application requirements increases the complexity of the middleware, due to the introduction of many cross-cutting concerns in the architecture, which are not properly modularized by traditional programming techniques, resulting in a tangling and spread of theses concerns in the middleware code. The presence of these cross-cutting concerns limits the middleware scalability and aspect-oriented paradigm has been used successfully to improve the modularity, extensibility and customization capabilities of middleware. This work presents AO-OiL, an aspect-oriented (AO) middleware architecture, based on the AO middleware reference architecture. This middleware follows the philosophy that the middleware functionalities must be driven by the application requirements. AO-OiL consists in an AO refactoring of the OiL (Orb in Lua) middleware in order to separate basic and crosscutting concerns. The proposed architecture was implemented in Lua and RE-AspectLua. To evaluate the refactoring impact in the middleware architecture, this paper presents a comparative analysis of performance between AO-OiL and OiL

Qualidade de água como tema para a socialização do conhecimento científico em região semi-árida brasileira

During the dry and rainy periods, in the Piranhas-Assu river hydrographic basin, variations in bacterioplankton and trophic state indexes were studied in the lotic and lentic environments. The means of total bacterial density wavered in the order of 107 organisms. mL-1 and they were higher in the rainy period. Cocci bacteria were numerically predominant in all sampling points, influencing the total abundance of bacterioplankton. Total bacterial biomass varied from 659 to 1997,3 µgC.L-1 due to the high values of filaments cellular volume. Total phosphorus amounted 108 µg.L-1 and it had a positive correlation with chlorophyll a (r = 0,94; p < 0,05) during dry period, when these variables presented higher concentrations. There wasn t a high spatial variation. The low transparency of water and the phosphorus and chlorophyll concentrations indicated eutrophic or hipereutrophic levels in studied points of reservoir. These variables, associated with high density and biomass values found, alert to the necessity of a constant monitoring of the semi-arid aquatic ecosystems, where the quality of water is affected by dry occurrence

Biomonitoramento da qualidade da água e ações em educação ambiental em dois açudes da bacia hidrográfica Apodi-Mossoró, RN

Water scarcity is a reality for the inhabitants of the Brazilian semiarid region. The problem, in quantitative terms , is caused due to local climatic conditions due mostly to a water deficit. Qualitatively, results of multiple uses and resulting contamination by human activities. Eutrophication is presented as a threat to the sustainable use of water resources, in order to favor the predominance of dense populations of cyanobacteria, which can be potentially harmful to human health. The aim of this study is to understand the population dynamics of phytoplankton and cyanobacteria to assess water quality of reservoirs Santa Cruz do Apodi and Pau dos Ferros belonging to bacia Apodi Mossoró-RN . Water samples were collected monthly between October 2011 and May 2012 in reservoirs Santa Cruz do Apodi and Pau dos Ferros, in this latter , in Jan/12 we performed a diel profile . The abiotic variables obtained in the field and in the laboratory were: water temperature , dissolved oxygen , pH , turbidity , transparency , total nitrogen and total phosphorus . Phytoplankton samples were collected with a plankton net and bottle of Van dorn . Were performed : identification , quantification , calculation of biovolume , classification into functional groups and index calculation phytoplankton assembly ( Q ) , cyanotoxins were quantified by ELISA . Statistical analyzes supported the evaluation of the dynamics between biotic and abiotic factors. A questionnaire was conducted to examine the conceptions of the population, education professionals and students. The reservoir of Pau dos Ferros, shallow , turbid and eutrophic showed dominance of the functional group SN throughout the sample period . The phytoplankton biomass ranged from 20 to 70 mm ³ . L - 1, the lowest values coincided with the increase of the mixing zone and transparency, which contributed to the occurrence of a change in species composition phytoplankton . The application of the index Q proved relevant, the reservoir of Pau dos Ferros , depending on the species present , was classified ecologically as bad for almost the entire sample period . The reservoir Santa Cruz do Apodi showed low biomass ( 0.04 and 4.31 mm ³ . L - 1 ) and greater diversity in the phytoplankton composition . According to the index assembly (Q ), it showed moderate condition during most of the period influenced by different functional groups of typical meso- eutrophic environment (K S0, H1, C, F , J , E, D and N) . Associations of diatoms and green algae D and X1 succeeded populations of cyanobacteria in periods marked by greater instability in the system , caused by wind or rain. In summary , the occurrence of drought has a direct influence on the hydrological conditions of the reservoirs , in general, these events, reducing the reservoir level is directly related to decreased water quality and increased density of phytoplankton occurring predominance of cyanobacteria , the index Q reflected well to changes in phytoplankton composition , being a good indicator for biomonitoring of reservoirs in this study and survey of previous conceptions showed the need to work on environmental awareness for the preservation of water resources by conducting workshops for Environmental Education

Impactos sócio-econômicos e ambientais da introdução da Tilápia do Nilo, Oreochromis niloticus, em açudes públicos do semi-árido nordestino, Brasi

The stocking of exotic fish, especially the tilapia, has become a common practice in the public reservoirs of the Brazilian semi-arid region. The stocking of tilapias has had as its main aim the improvement of the fisheries in the reservoirs and consequently the improvement of the socio-economic conditions of the families that have fishing as the main source of income. However, the environmental risks associated with this practice are high and can lead to a loss in aquatic biodiversity and to changes in the quality of the water. The object of this work was to quantify the socio-economic and environmental effects of the introduction of the Nile tilapia in the public reservoirs of the semi-arid northeastern Brazil. The analysis of the fish yield of 100 public reservoirs from 1970 to 2000 demonstrated that the introduction of the Nile tilapia apparently contributed to an increase in the total fish yield from the late 1970 s until the mid-1980 s. Nevertheless, from that time onwards the fish yield in these reservoirs has fallen into decline to levels inferior to those observed prior to the introduction of the tilápia. The analysis of the fishing activity statistics of the Gargalheiras reservoir located in the city of Acari, Rio Grande do Norte, demonstrated that the introduction of the Nile tilapia in the reservoir has not significantly increased the fish yield, the gross overall income, the gross per capita income nor the number of fishermen actively fishing in the reservoir. On the other hand, the analysis of the fishing activity statistics of the Gargalheiras reservoir has revealed a significant reduction in the captures of other commercially important fish species after the introduction of the tilapia. This result suggests that the Nile tilapia could have negatively affected other species of fish in the reservoir, contributing to the decline in their stocks. In order to assess the perception of the fishermen concerning the effects of the Nile tilapia over other species of fish and the quality of the water, questionnaires containing open and multiple choice questions were applied with 30 fishermen from the colony of the Gargalheiras reservoir. The great majority of the local fishermen stated that the tilapia is currently the most important species of fish to those who depend on fishing as a source of income and that they have not caused damage to other species of fish nor to the quality of the water in the reservoir. However, the results of the present work indicate that the alleged socio-economic benefits, employed to justify the introduction of the Nile tilapia in the reservoirs, are overestimated while the environmental impacts of the introduction of this exotic species are underestimated

O FUNDEF e o FUNDEB como política de financiamento para a valorização do magistério: efeitos na carreira e na remuneração dos professores da rede pública e estadual de ensino do RN.

Este estudio analiza los efectos de la política de financiamiento de la educación básica, por intermedio de los Fundos contables, Fundef y Fundeb, y su proposición en valorar el magisterio, considerando las dimensiones de carrera y de la remuneración de los profesores de la red pública estadal de enseñanza del estado de Rio Grande do Norte, en el período entre 1996 y 2010. Para entender las condicionantes de la evaluación de las políticas públicas, se buscó también las contribuciones de Marx (1996) segundo quién “el concreto es concreto” y que la dialéctica del concreto se puede auxiliar en el intento de captar el fenómeno estudiado. Se utilizó aún, el referencial teórico bibliográfico relacionado al financiamiento de la educación y a la valoración del magisterio, a partir de la literatura referente a las dimensiones del objeto (fundef y Fundeb) y (carrera y remuneración). En la investigación documental, además de las legislaciones, directrices nacionales y locales pertinentes, se utilizaron datos referentes a los recursos disponibles en la Finbra. Tesoro Nacional, SIOPE/RN, INEP/MEC, datos de resumen del folio y folio de pagamiento de Secretaria de Estado, de la Educación e de la Cultura (SEEC), y 289 sueldos de 21 profesores. Se realizó entrevista semi estructurada con nueve profesores, referente a la carrera, además de un cuestionario aplicado a 12 profesores relacionado a remuneración. Se considera que en los resultados referentes a los indicadores educacionales, en el período Fundef ocurrió una reducción en las inscripciones de la red pública de enseñanza, como también en las funciones docentes, de la enseñanza base (fundamental), que corresponde a 37%. A partir de la vigencia del Fundeb (2007 – 2010), estos indicadores fueron puestos en ecuación. En todo el período entre 1996 a 2010, ocurre un aumento en las inscripciones de 119,03% y en las funciones docentes de 77,44%. Sobre los datos de financiamiento, se constató que, del mínimo exigido (60%) en la aplicación de recursos de los Fundos en la remuneración del magisterio se aplica en el período de los dos Fundos, pero el mínimo exigido, o sea, 83,29% a 98,89% de los recursos. Los efectos de los Fundos en la carrera de los nueve profesores, considerando la promoción y la progresión, no han sido satisfactorios. En la promoción de los nueve de estos docentes, apenas uno evolucionó el Nivel (titulación), pero retrocedió en la progresión. En la progresión de los nueve profesores, ocho se hallan con la progresión retrasada, entre dos y cinco clases, acumulando un perjuicio que varía de 10% a 45% en su ganancia. La diferencia de una clase a otra corresponde a 5% en la renta anual. Se observa que las ventajas pecuniarias contribuyen con la remuneración con porcentaje más alto que la renta, disminuyendo esta diferencia en el período de Fundeb. Sobre la remuneración, un profesor con 24 años de carrera, con formación (magisterio), no consigue, después de años de profesión, ganar ni siquiera dos salarios mínimos. El profesor con 30 años de carrera, con maestría, tiene una renta, en 2010, correspondiente a menos de tres salarios mínimos, o sea, 2,82 y una remuneración que equivale a poco más de tres salarios mínimos, o sea, 3,66. Si comparamos la profesión de magisterio con otras que igual exigen formación superior, la primera es, en general, de bajo nivel, causando un resultado negativo sobre la búsqueda de la profesión del magisterio. Por los efectos en la remuneración, se concluye que hubo una mejoría, pero aún insuficiente, sobre todo al comparar con el Salario Mínimo Anual. Se evalúa, una vez que los fundos – Fundef y Fundeb – no fueron capaces de promover la valoración del magisterio en las dimensiones de la carrera y de la remuneración. Se constatan algunos resultados negativos en la política de Fundo ya que tendría que ver, principalmente, con la incapacidad de la referida política a valoración de magisterio, siendo una de las causas, o financiamiento con restricción de presupuesto.

Uma linguagem de descrição arquitetural baseada em uma arquitetura de referência para sistemas ubíquos

A computação ubíqua é um paradigma no qual dispositivos com capacidade de processamento e comunicação são embutidos nos elementos comuns de nossas vidas (casas, carros, máquinas fotográficas, telefones, escolas, museus, etc), provendo serviços com um alto grau de mobilidade e transparência. O desenvolvimento de sistemas ubíquos é uma tarefa complexa, uma vez que envolve várias áreas da computação, como Engenharia de Software, Inteligência Artificial e Sistemas Distribuídos. Essa tarefa torna-se ainda mais complexa pela ausência de uma arquitetura de referência para guiar o desenvolvimento de tais sistemas. Arquiteturas de referência têm sido usadas para fornecer uma base comum e dar diretrizes para a construção de arquiteturas de softwares para diferentes classes de sistemas. Por outro lado, as linguagens de descrição arquitetural (ADLs) fornecem uma sintaxe para representação estrutural dos elementos arquiteturais, suas restrições e interações, permitindo-se expressar modelo arquitetural de sistemas. Atualmente não há, na literatura, ADLs baseadas em arquiteturas de referência para o domínio de computação ubíqua. De forma a permitir a modelagem arquitetural de aplicações ubíquas, esse trabalho tem como objetivo principal especificar UbiACME, uma linguagem de descrição arquitetural para aplicações ubíquas, bem como disponibilizar a ferramenta UbiACME Studio, que permitirá arquitetos de software realizar modelagens usando UbiACME. Para esse fim, inicialmente realizamos uma revisão sistemática, de forma a investigar na literatura relacionada com sistemas ubíquos, os elementos comuns a esses sistemas que devem ser considerados no projeto de UbiACME. Além disso, com base na revisão sistemática, definimos uma arquitetura de referência para sistemas ubíquos, RA-Ubi, que é a base para a definição dos elementos necessários para a modelagem arquitetural e, portanto, fornece subsídios para a definição dos elementos de UbiACME. Por fim, de forma a validar a linguagem e a ferramenta, apresentamos um experimento controlado onde arquitetos modelam uma aplicação ubíqua usando UbiACME Studio e comparam com a modelagem da mesma aplicação em SySML.

O impacto da remoção de peixes sobre a dinâmica e estrutura dos grupos funcionais fitoplanctônicos em um lago raso tropical durante uma seca severa

The artifi cial eutrophication is one of the biggest t h reat for the quality of aquatic ecosystems in the whole world. The expectations for the future climatic scenarios in arid and semi - arid regions are intense and frequent droughts enhancing the risk of eutrophicati on and cyanobacterial blooms. Restoration techniques of eutrophic lakes were proposed to reduce nutrient loading and improve the water quality. A successful technique used in temperate regions is the biomanipulation by benthivorous fish removal . Our hypoth esis is that the benthivorous fish removal reduces phytoplankton total biomass and change the composition of phytoplankton functional groups, improving water quality. The aim of the study was evaluate the impact of biomanipulation on phytoplankton function al groups and in the water quality. We applied the technique of biomanipulation in the artificial lake ESEC, in a semi - arid region of Brazil and analyzed the physical and chemical variables and the dynamic of phytoplankton functional groups monthly during November 2012 to August 2013. With the removal of benthivorous fish we observed a significant increase of the euphotic depth, phytoplankton richness and the recruitment of green algae (groups F and J ), indicators of good water quality. However, we did not observe significant differences on total phosphorous concentration and on phytoplankton biomass and diversity. The drought effect in the region during the study was evident , promoting a drastic reduction on water level which influenced the availability of resource and affected phytoplankton community before the biomanipulation. To evaluate the effect of severe drought on the dynamic of phytoplankton functional groups and test if the drought periods are favorable to dominance of cyanobacterial groups, we stu died two artificial neighbors lakes (ESEC and Pocinhos) in a semi - arid tropical region during May 2012 to February 2013. We observed a temporal differentiation of biotic and abiotic variables caused by drought. Both lakes presented reduction of 2 meters of water level and increase on conductivity, turbidity, nutrients concentration and a reduction on water transparency, during the severe drought. The deeper lake (Pocinhos) increased phytoplankton total biomass and presented cyanobacterial functional group d ominance (group S N ) and the shallower lake (ESEC) reduced phytoplankton total biomass and presented dominance of mixotrophic and flagellate functional groups (groups W 1 e W 2 ). Summarizing, the knowledge of the effects of benthivorous fish removal in semi - a rid tropical lakes still unknown and this study had limitations caused by the impact of drought. Thus, it is necessary a long term monitoring to investigate the real effects of biomanipulation on the functioning of the studied ecosystems. Otherwise, period s of drought could have opposite effects (increase or reduction) on total biomass and composition of phytoplankton functional groups. Drought not always leads to dominance of cyanobacterial groups.