Review: There is a continual need for current introductory material in key ecological areas.This is especially so in something as diverse as streams and where current public interest (in terms of water supply and global warming) is focussed.

One of the key issues with stream ecology is that there are an enormous range of situations to deal with from the tiny brook to the largest river with concomitant variations in key factors such as water supply and geology. It is interesting to see therefore that these authors have chosen to focus on that which unites rather than divides with the assumption that there are processes and factors common to all systems whatever their size. This diversity is the focus of chapter one. Here we get not only an overview of the diversity of river systems but also some basic nomenclature (a key feature and often missed) and a hint of how rivers far today. Chapter two looks at the physics of streamflow from water balance and stream topography to variations in flow. Chapter three takes on the physical side of the river with an examination of the geomorphology of rivers. Here the focus is on the stream channel and the parameters which produce it. There's also a useful treatment of the stream continuum - the idea that processes occur along the stream but one or more may be dominant at any one point. This is important - too many studies make the environmental gradient look static at a point and this can reduce effective understanding especially if such a perspective is carried over to management. Chapter four is a brief review of chemistry - the key components in rivers and how they vary. Chapter five continues the physical theme with a study of the abiotic components - flow, substrate and temperature. Chapter six signals a focus from the abiotic to the biotic with an exploration of the plant components in a stream - algae, macrophytes and plankton. We see how and why distributions vary. Detritus is an important energy source in many streams and the way this is utilised is the subject of chapter seven. One of the main elements of any study of stream ecology is to demonstrate how feeding relationships are set up and maintained i.e. food webs and chains. This is perhaps one of the first studies by the beginner and understanding the way in which trophic relationships are constructed is a vital learning process. At this stage one has the basic components of stream ecology - an understanding of the physical environment and some idea of food webs. This in itself is a great end point to a study but there are other areas which are required for a deeper understanding. For example, chapter 9 looks at interactions between species. The impact of herbivory, predation and competition adds another dimension to the picture. Chapter 10 tries an overview of the stream community showing how local diversity is shaped and community structure defined . A further change in direction is provided with chapter 11 which looks at the changes in nutrient flow. Key elements are the cycling of nitrogen and phosphorous (especially given the well known impact of phosphorous additions into oligotrophic environments. There's also a look at transport and some of the other variables in producing the nutrient budget. This can be tied in to chapter 12 which examines the stream metabolism and the movement of C through the system. Even though human impact was mentioned at the start it's not until chapter 13 that it can be studied in more detail. There's no shortage of ways people can impact on stream ecosystems and so only the biggest rate a mention here. A final, brief chapter outlines the nature of stream ecology and how it might proceed.

This is an interesting text. It has a wealth of detail, quite dense in places, that means it is for the more "advanced" beginner. Aimed at senior undergraduates the level of detail is such that it would prove difficult to understand by junior classes. However, it does provide both teachers and field study centres with a much-needed overview of stream ecology. Coverage is comprehensive and many of the diagrams would make excellent resources. Set against this, chapter order is somewhat fluid with no obvious direction and although this is a minor point it does detract from the otherwise great value of the text. Overall, a must for the field centre and a good starter text in stream ecology.