Biota

As with all ecosystems, river systems involve a complex interaction of a rich diversity of micro-organisms, plants and animals with their physical and chemical environment. The river habitat presents unique problems for organisms exposed to unidirectional currents, seasonal variation in flow, and disturbance due to pollution and other human interference. The book starts with a description of the taxa, their adaptations and their ecologies, followed by chapters describing the ecosystem processes in terms of trophic interactions and the key production processes related to photosynthesis and decomposition. A major chapter then considers the principles, practices and problems associated with making reliable observations on river organisms, leading to final chapters investigating how river biota are impacted by human activity and how, in turn, they can be used as indicators of these effects in river-management programmes.

Some pioneers in soil research such as Müller and Kubiëna were as much biologists as they were soil scientists and the legendary biologist Charles Darwin was foresighted in recognizing the earthworms as instrumental in reworking the soil, thereby forming what he called "vegetable mould". Still, soil science has largely been the realm of physicists and chemists over the past decades. Whatever the reason, this picture is rapidly changing. Until recently, research on the transport and transformation of elements in soil was often concerned with either soil biota/plant relationships or with soil structure/plant relationships, if the biota were considered at all, but very few studies explicitly took the interrelationships between soil structure and soil biota into account. The conference on Soil Structure/Soil Biota Interrelationships, held at Wageningen, The Netherlands, 24-28 November 1991, was meant to bridge that gap, focussing on methods of research, organized in three levels: features, processes and effects. The proceedings of the conference are testimony of the need to intertwine the biological, morphological, physical and chemical disciplines in soil research to understand better and forecast soil properties and processes as related to land use for agricultural and other purposes. This book should be of particular interest to soil scientists and ecologists who feel the need for a cross-disciplinary approach in soils research. It should also be a rich source of teaching material for courses in soil science and soil ecology at graduate level and above, with ample reference to studies on land use as related to agriculture and the environment.

Examining tissue residues of contaminants in biota reveals the movement of contaminants within organisms and through food chains as well as the context for understanding and quantifying injuries to organisms and their communities. Yet tissue concentrations of some contaminants are especially challenging to interpret and the ability of today’s analytical chemists to provide reliable analytical data of most important environmental contaminants often surpasses the ability of ecotoxicologists to interpret those data. Offering guidance on the ecotoxicologically meaningful interpretation of tissue concentrations, Environmental Contaminants in Biota, Interpreting Tissue Concentrations, Second Edition is updated with current data and new ways of analyzing those data as well as additional contaminants not previously considered. Beginning with a history of wildlife toxicology and data interpretation, chapters cover a wide range of contaminants and their hazardous and lethal concentrations in various animals including DDT, Dioxins, PCBs, and PBDEs in aquatic organisms; methylmurcury, selenium, and trace metals in fishes and aquatic invertebrates; and pharmaceuticals and organic contaminants in marine mammals. The book considers the impact of Polychlorinated Biphenyls, Dibenzo-p-Dioxins and Dibenzofurans, and Polybrominated Diphenyl Ethers; cyclodiene; and other organochlorine pesticides in birds and mammals. Later chapters examine the effects and analysis of lead, cadmium, and radionuclides in biota. With thousands of published research papers reporting tissue concentrations each year, Environmental Contaminants in Biota, Interpreting Tissue Concentrations, Second Edition gives ecotoxicologists the ability to draw actionable value regarding the toxicological consequences of those concentrations and relate tissue concentrations quantitatively to injury: the core of ecotoxicology.

The presence of concentrations of organic substances and cations in sea water is a matter of increasing concern to the water industry, environmentalists and the general public alike. There is a threat of possible health hazards to both human, fish and crustacea. Occurrence, Toxicity and Analysis of Marine Biota discusses bioaccumulation in biota as well as occurrence and analysis of toxicants in biota. The main thrust of this book will be a review of the levels of toxicants found in the tissues of fish and invertebrates at various sites throughout the world. In addition, results will be reported on the levels of toxicants found in marine biota enabling ill health or death to occur. This will involve a discussion of toxicity index LC50 and percentile S95 concentration of toxicants and their implications on animal health and mortality, also that of humans who eat these sea creatures. The book will be a complete logical survey of this topic.