H. Barth – författare

Many previous studies and books have been dedicated to fundamental and developmental aspects of biomarkers. The purpose of this book is to provide, through various case studies, an overview of the practical use of biological markers in marine animals to evaluate the health effects of environmental contamination in marine ecosystems.More precisely, the book presents the results obtained during the development and application of biological markers as indicators of exposure/effect to toxic chemicals in marine environments, using diverse sentinel species such as fish, bivalves and crustaceans. An important aspect is also the publication of technical annexes that describe in detail the experimental procedures developed for both chemical and biochemical measurement.

Many previous studies and books have been dedicated to fundamental and developmental aspects of biomarkers. The purpose of this book is to provide, through various case studies, an overview of the practical use of biological markers in marine animals to evaluate the health effects of environmental contamination in marine ecosystems.More precisely, the book presents the results obtained during the development and application of biological markers as indicators of exposure/effect to toxic chemicals in marine environments, using diverse sentinel species such as fish, bivalves and crustaceans. An important aspect is also the publication of technical annexes that describe in detail the experimental procedures developed for both chemical and biochemical measurement.

PH. BOURDEAU Directorate-General Science. Research and Development. Commission of the European Communities. Brussels. Belgium We are living on a unique planet, the only one in the solar system where life exists. The very existence of life has modified the physical and chemical environment of the earth, its atmosphere and oceans, in a way that makes life sustainable. This system with its complex cybernetic mechanisms has been named GAIA by Lovelock. Man has always interfered with it on a more or less limited scale. This interference is now reaching global proportions such as climate modifications resulting from CO and trace gas 2 accumulation in the atmosphere or the destruction of stratospheric ozone, not to speak of global radioactive contamination. GAIA will probably prevail as a living system but it probably does not give much importance to man''s survival as such, and it is man that has to take care of his own survival. In the ecosystem of Planet Earth, soils are the thin interface between lithosphere and atmosphere which constitutes the essential substrate for the terrestrial biosphere, the productivity of which far exceeds that of the oceans, even though the latter cover a much larger area than the continents. Soils themselves are complex systems. They develop through weathering of minerals, are colonised by living organisms which in turn modify their substrate making it suitable for other organisms. This induces a primary ecological succession which eventually reaches a climax, in equilibrium between climate, soil and the biological communities.

In these essays toward a political philosophy we shall be con­ cerned with fundamentals. And because it is a question of fundamentals, they will, we imagine, be of interest to many readers. We should like to contribute to a clarification, histor­ ically and systematically, of some concepts with which every philosophy of society and the state has to deal. We shall admit historical considerations for the sake of insights into the sys­ tematic ones, and we trust that our inquiry into the systematic will help us to understand the historical. For we are moving in that circle exemplarily described by Johann Gustav Droysen in his Vorlesungen fiber Enzyklopadie und Methodologie der Ge­ schichte (§ 37) when he writes: ''Undoubtedly we only under­ stand completely that which is, when we recognize and make clear to ourselves how it came to be. But how it came to be, we recognize only if we investigate and understand, as exactly as possible, how it is. Our grasping that which came to be and comprehending its becoming is only one form and expression of our understanding of the present and existing. And this becoming and having come to be can be derived only by temporally conceiving and analysing the existing in order to understand it. '' We must, therefore, center our attention on what may be called the structure and logic of social order.

In these essays toward a political philosophy we shall be con­ cerned with fundamentals. And because it is a question of fundamentals, they will, we imagine, be of interest to many readers. We should like to contribute to a clarification, histor­ ically and systematically, of some concepts with which every philosophy of society and the state has to deal. We shall admit historical considerations for the sake of insights into the sys­ tematic ones, and we trust that our inquiry into the systematic will help us to understand the historical. For we are moving in that circle exemplarily described by Johann Gustav Droysen in his Vorlesungen fiber Enzyklopadie und Methodologie der Ge­ schichte (§ 37) when he writes: 'Undoubtedly we only under­ stand completely that which is, when we recognize and make clear to ourselves how it came to be. But how it came to be, we recognize only if we investigate and understand, as exactly as possible, how it is. Our grasping that which came to be and comprehending its becoming is only one form and expression of our understanding of the present and existing. And this becoming and having come to be can be derived only by temporally conceiving and analysing the existing in order to understand it. ' We must, therefore, center our attention on what may be called the structure and logic of social order.