The large lakes of the East African Rift Valley are among the oldest on Earth, and are vital resources for the people of their basins. They are unique among the large lakes of the world in terms of their sensitivity to climatic change, rich and diverse populations of endemic species, circulation dynamics and water-column chemistry, and long, continuous records of past climatic change. A comprehensive study of the large African lakes is long overdue. The scientific justification for such an effort is noted in the previous paragraph and is illustrated in great detail in this volume. Societal need for the sustainable utilization of these lakes offers an even more compelling reason for examination of biological food webs, water quality, and past climate variability in East Africa. The lakes provide the most important source of protein for the people of the African Rift Valley, and fish populations are shifting dramatically in response to fishing pressure, introduction of exotic species, land use impact on water quality, and perhaps climatic change. Current estimates of primary productivity, the underpinning of the food resource, are extremely crude and based on only a few spot measurements.

Ponds are a primary production system to a wide variety of freshwater fish species. Each species have specific and unique nutrient needs and successful pond fertilization is critical to a successful aquaculture enterprise. Aquaculture Pond Fertilization: Impacts of Nutrient Input on Production provides state-of-the-art information for successful fertilization strategies for a broad range of pond-raised species. Aquaculture Pond Fertilization attempts to rectify the seemingly contradictory nutrient recommendations by clearly defining the goals of specific types of aquaculture. Chapters are divided into three sections: The first reviews basic concepts in fertilization applicable to all pond-based production. The second looks at specific nutrient management approaches. The third and final section of chapters looks specifically at key freshwater pond species ranging from tilapia to perch and discusses specific fertilization needs for the successful rearing of these in-demand fish. Looking across species with chapters contributed by leaders in the field Aquaculture Pond Fertilization provides succinct single-volume coverage of an oft-neglected, but vitally important topic in aquaculture production.

Humankind has pervasively influenced the Earth’s atmosphere, biosphere, geosphere, hydrosphere and cryosphere, arguably to the point of fashioning a new geological epoch, the Anthropocene. To constrain the Anthropocene as a potential formal unit within the Geological Time Scale, a spectrum of indicators of anthropogenically-induced environmental change is considered, and shown as stratigraphical signals that may be used to characterize an Anthropocene unit, and to recognize its base. This volume describes a range of evidence that may help to define this potential new time unit and details key signatures that could be used in its definition. These signatures include lithostratigraphical (novel deposits, minerals and mineral magnetism), biostratigraphical (macro- and micro-palaeontological successions and human-induced trace fossils) and chemostratigraphical (organic, inorganic and radiogenic signatures in deposits, speleothems and ice and volcanic eruptions). We include, finally, the suggestion that humans have created a further sphere, the technosphere, that drives global change.

Advances in Marine Biology

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.