The role of ecotoxicology for monitoring ecosystem health

The proposed EC Water Framework Directive (WFD)incorporates some new concepts in the field of water protection. Most of these concepts rely on the use of applied ecology of water systems. The expected improvement of environmental management is very new in this context. The new WFD will allow the checking of the eco-epidemiological results of several human impacts on aquatic ecosystems, such as toxic pollution and habitat modification. This paper intends to show some consequences of the WFD in the field of ecotoxicology.

Climate change and its risk reduction by mangrove ecosystem of Bangladesh

Climate change is amongst the most dreaded problems of the new millennium. Bangladesh is a coastal country bounded by Bay of Bengal on its southern part and here natural disasters are an ongoing part of human life. This paper discusses about the possible impact of climate change through tropical cyclones, storm surges, coastal erosion and sea level rise in the coastal community of Bangladesh and how they cope with these extreme events by the help of mangrove ecosystem. Both qualitative and quantitative discussions are made by collected data from different research work those are conducted in Bangladesh. Mangrove ecosystem provides both goods and services for coastal community, helps to improve livelihood options and protect them from natural disaster by providing variety of environmental support

The Semiglades: the collision of restoration, social values, and the ecosystem concept

Opinion article

Comparative studies on the structure of an upland African stream ecosystem

Upland stream systems have been extensively investigated in Europe, North America and Australasia and many of the central ideas concerning their function are based on these systems. One central paradigm, the river continuum concept is ultimately derived from those North American streams whose catchments remain forested with native vegetation. Streams of the tropics may or may not fit the model. They have been little studied. The Amani Nature Reserve in the East Usambara Mountains of north-eastern Tanzania offers an opportunity to bring these naturally forested systems to the attention of the ecological community. This article describes a comparison made between two lengths of the River Dodwe in this area. The work was carried out by a group of postgraduate students from eighteen European and African countries with advice from five staff members, as part of a course organised by the Tropical Biology Association. Rigorous efforts were made to standardise techniques, in a situation where equipment and laboratory facilities were very basic, through a management structure and deliberate allocation of work to specialists in each area.The article offers a summary of invertebrate communities found in the stream and its biomass. Crabs seem to be the key organism in both sections of the streams.

Investigations of certain eco-physiological characteristics of the broad and long-pincered crayfish in connection with their interspecific relationships. [Translation from: Lietuvas TSR Mokslu Akademijos Darbai, C Serija 2(40), 279-286, 1966.]

The results are described of eco-physiological investigations of the broad-pincered (Astacus astacus L.J.) crayfish and the long-pincered (Astacus astacus Esch.) crayfish, conducted in 1963—64 in the Institute of Zoology and Parasitology of the Academy of Science of the Lithuanian SSR, for the purpose of studying the interspecific relationship of these two species. In the course of the investigation were determined: the influence of the temperature of the environment on the consumption of oxygen by full grown individuals of both species and on the respiratory movements of the scaphognathites, the threshold temperatures and the saturation of the water by oxygen, the diel activity in the winter period.

Aspects of the biology of coarse fish in the Dorset Stour

Some of the results from an investigation of five species of coarse fish, in the Stour River, carried out from 1968-1978 are presented in this article. The species involved were: Rutilus rutilis, Leuciscus leuciscus, L. cephalus, Esox lucius and Perca fluviatilis : which are of particular interest to anglers. Although these species show some similarities, as in the shape of the annual and seasonal growth curves, in most other respects each species occupies a distinct niche in the ecosystem and has a life-history strategy peculiar to itself. In this study only 5 species were investigated. When all the species present are considered the relationships or diversities suggested here will therefore be made far more complex.

Oxygen relationships in intermittent sand filtration of wastewaters

A model for some of the many physical-chemical and biological processes in intermittent sand filtration of wastewaters is described and an expression for oxygen transfer is formulated.

The model assumes that aerobic bacterial activity within the sand or soil matrix is limited, mostly by oxygen deficiency, while the surface is ponded with wastewater. Atmospheric oxygen reenters into the soil after infiltration ends. Aerobic activity is resumed, but the extent of penetration of oxygen is limited and some depths may be always anaerobic. These assumptions lead to the conclusion that the percolate shows large variations with respect to the concentration of certain contaminants, with some portions showing little change in a specific contaminant. Analyses of soil moisture in field studies and of effluent from laboratory sand columns substantiated the model.

The oxygen content of the system at sufficiently long times after addition of wastes can be described by a quasi-steady-state diffusion equation including a term for an oxygen sink. Measurements of oxygen content during laboratory and field studies show that the oxygen profile changes only slightly up to two days after the quasi-steady state is attained.

Results of these hypotheses and experimental verification can be applied in the operation of existing facilities and in the interpretation of data from pilot plant-studies.

Strategic ecosystem studies of large slow flowing lowland rivers. Progress report: April - October 1989

This report covers the period April to September, 1989. During this period sampling of invertebrates has concentrated on planktonic animals and those associated with one of the dominant macrophytes in the system, Nuphar lutea, the yellow water lily, since these are particularly important in the diets of larval and juvenile cyprinid fish. A proportion of samples has been partly analysed and some preliminary data are presented here.

'The highly nervous system of the English Lakes': aquatic ecosystem sensitivity to external changes, as demonstrated by diatoms.

The author reviews the stratigraphic diatom profile of Cumbrian lakes since the last glaciation. Knowledge of both present and previous interglacials suggests that a natural cycle of change is imposed on all lakes. The nature of inwashed material is dependant on climatic and natural soilcycles and this affects the water quality and sensitive aquatic biota. Anthropogenic effects are superimposed upon this with forest clearance and pollution. Whilst some Cumbrian diatom profiles extend over the entire post glacial, others cover only detailed sections relating to particular problems. Causes and effect of recent changes in lakes can be studied using indicator species but palaeocology contributes greatly to understanding of long term changes.

The application of methods of ecosystem analysis to the evaluation of water quality

Guided by experience and the theoretical development of hydrobiology, it can be considered that the main aim of water quality control should be the establishment of the rates of the self-purification process of water bodies which are capable of maintaining communities in a state of dynamic balance without changing the integrity of the ecosystem. Hence, general approaches in the elaboration of methods for hydrobiological control are based on the following principles: a. the balance of matter and energy in water bodies; b. the integrity of the ecosystem structure and of its separate components at all levels. Ecosystem analysis makes possible a revelation of the whole totality of factors which determine the anthropogenic evolution of a water body. This is necessary for the study of long-term changes in water bodies. The principles of ecosystem analysis of water bodies, together with the creation of their mathematical models, are important because, in future, with the transition of water demanding production into closed cycles of water supply, changes in water bodies will arise in the main through the influence of 'diffuse' pollution (from the atmosphere, with utilisation in transport etc.).

Alterations of the global water cycle and their effects on river structure, function and services

River structure and functioning are governed naturally by geography and climate but are vulnerable to natural and human-related disturbances, ranging from channel engineering to pollution and biological invasions. Biological communities in river ecosystems are able to respond to disturbances faster than those in most other aquatic systems. However, some extremely strong or lasting disturbances constrain the responses of river organisms and jeopardise their extraordinary resilience. Among these, the artificial alteration of river drainage structure and the intense use of water resources by humans may irreversibly influence these systems. The increased canalisation and damming of river courses interferes with sediment transport, alters biogeochemical cycles and leads to a decrease in biodiversity, both at local and global scales. Furthermore, water abstraction can especially affect the functioning of arid and semi-arid rivers. In particular, interception and assimilation of inorganic nutrients can be detrimental under hydrologically abnormal conditions. Among other effects, abstraction and increased nutrient loading might cause a shift from heterotrophy to autotrophy, through direct effects on primary producers and indirect effects through food webs, even in low-light river systems. The simultaneous desires to conserve and to provide ecosystem services present several challenges, both in research and management.

Mechanisms involved in Escherichia coli and Serratia marcescens removal during activated sludge wastewater treatment

Wastewater treatment reduces environmental contamination by removing gross solids and mitigating the effects of pollution. Treatment also reduces the number of indicator organisms and pathogens. In this work, the fates of two coliform bacteria, Escherichia coli and Serratia marcescens, were analyzed in an activated sludge process to determine the main mechanisms involved in the reduction of pathogenic microorganisms during wastewater treatment. These bacteria, modified to express green fluorescent protein, were inoculated in an activated sludge unit and in batch systems containing wastewater. The results suggested that, among the different biological factors implied in bacterial removal, bacterivorous protozoa play a key role. Moreover, a representative number of bacteria persisted in the system as free-living or embedded cells, but their distribution into liquid or solid fractions varied depending on the bacterium tested, questioning the real value of bacterial indicators for the control of wastewater treatment process. Additionally, viable but nonculturable cells constituted an important part of the bacterial population adhered to solid fractions, what can be derived from the competition relationships with native bacteria, present in high densities in this environment. These facts, taken together, emphasize the need for reliable quantitative and qualitative analysis tools for the evaluation of pathogenic microbial composition in sludge, which could represent an undefined risk to public health and ecosystem functions when considering its recycling.

Effects of global change on the functioning of Mediterranean Rivers

138 p.

A vida após a alta

Esta tese discute a vida após a alta hospitalar através de uma etnografia da experiência de um grupo de famílias, ao cuidarem de um membro dependente de cuidados de saúde. Foi realizada entre agosto de 2001 e julho de 2005 em Juiz de Fora-MG. O foco da investigação foi a convivência cotidiana da família com um membro requerendo cuidados de saúde especializados após ter recebido assistência de alta complexidade. O objetivo foi compreender a questão: como a família cuida, em casa, de um familiar que necessita de cuidados de saúde após a alta hospitalar? Adotamos a etnografia orientada por Geertz (1989), que nos permitiu, através da análise interpretativa das teias de significados apreendidas pela observaçãoconvivência com os sujeitos, uma compreensão de como o fenômeno (cuidado) se evidencia e se transforma em experiência nas relações que se estabelecem dentro e fora da família. A identificação das famílias-sujeito iniciou com a observação das internações na Unidade de Terapia Intensiva (UTI) do Hospital Universitário da Universidade Federal de Juiz de Fora, no segundo semestre de 2003, seguida da observação nas enfermarias e, posteriormente, nos seus domicílios. De 137 pacientes internados nesta UTI naquele semestre, 59 foram a óbito, 12 foram transferidos para outro hospital da cidade, por demandarem tecnologias não oferecidas pela instituição e 66 tiveram alta hospitalar na condição de melhorado. Destes, observamos 12 casos, residentes na cidade de Juiz de Fora, que compartilham de uma mesma cultura assistencial e que foram submetidas a um mesmo padrão de organização e de fluxo de atendimento no sistema de saúde local. Destas, uma família se destacou como principal sujeito, pela repetição de eventos significativos à questão principal da pesquisa e utilizamos dados de outras cinco dentre as observadas. Os dados foram arquivados em um banco de dados qualitativos LOGOS. A prioridade nos cuidados com o corpo; a dependência dos serviços de saúde especializados do SUS e as alterações na organização e no funcionamento da família, com redefinições de papéis, para se adaptar à realidade de convivência com um membro doente, estão dentre os achados. Dois fenômenos que se relacionam com o desenvolvimento da experiência de cuidar pelas famílias se destacaram: a individualização na família, que parece influenciar a forma de abordagem clínica (individualizada) pelos profissionais de saúde, e uma concepção de família como sujeito coletivo Bourdieu (1998) como possibilidade para o planejamento de ações coletivas. O sofrimento, observado pela contínua convivência dos sujeitos com sentimentos de angústia nas trajetórias de busca de cuidados no Sistema, nas instituições de saúde, evidenciou a desassistência a que esse grupo de cidadãos está exposto no modelo assistencial vigente. A lida das famílias com uma diversidade de cuidados, incluindo a prática de cuidados técnicos desencadeou uma rede extrafamiliar de aproximações, para o enfrentamento das necessidades. Apesar da dependência de tecnologias, de saberes técnicos e das restrições no acesso a esses, evidenciou-se um tipo de autonomia pelos sujeitos na prática de cuidados no espaço intrafamiliar e no entorno micro-sociológico de convivência. No Sistema de Saúde a preferência primeira das famílias para busca de ajuda é o hospital, depois, as unidades de referência secundária e, por último, as Equipes de Saúde da Família (ESF). A procura pelas ESF é por que estas representam parte obrigatória no fluxo inicial dos usuários do SUS local, garantem a aquisição de medicamentos, oferecem serviços de natureza cartorial, como atestados e pareceres para juiz e, ainda, encaminhamentos e solicitação de exames.

Entrelaçamento dos planos da linguagem na literatura juvenil contemporânea: alternativas de leitura

A proposta da tese é investigar o papel da linguagem na indicação das obras literárias (juvenis) contemporâneas. Para operacionalizá-la, mergulha-se na análise dos textos em busca de marcas lingüístico-discursivas que revelam seu padrão de qualidade, observando a Língua Portuguesa em funcionamento: suas manifestações fonológicas, morfológicas, sintáticas, semânticas geradoras de efeitos de sentido inéditos, a fim de abrir espaço no chamado cânone literário, incorporando novos títulos e escritores brasileiros. Pretende-se traçar um percurso alternativo de leituras, visando à conquista de alunos matriculados no final do Ensino Fundamental e Ensino Médio, para que se tornem membros, de fato, da comunidade de leitores, cujos horizontes não se limitam ao período escolar. Objetiva-se, portanto, desenvolver no educando habilidades de leitura, interpretação e expressão (oral e escrita) em sua língua materna, levando-o a refletir sobre a língua no processo de ensino-aprendizagem. Como a tese privilegia a tríade Língua Portuguesa-Ensino-Leitura, tendo como corpus o discurso literário, busca-se sensibilizar o estudante para questionar-se acerca das escolhas lingüístico-discursivas do escritor na elaboração estética de sua narrativa, com o fito de ativar a participação do leitor na construção de sentido(s) da história. Intenta-se, enfim, ter a língua como o próprio tema das aulas de Português, focalizando a relação entre a produção dos textos e suas finalidades interativas