Life and its place across the planet

Freshwater Ecology is a new textbook for undergraduate students approaching biological limnology for the first time. Assuming little specialist knowledge, the book ably introduces the student to a fascinating subject that requires a synoptic understanding of several disciplines.

The authors divide the book into three parts, each including examples from rivers, lakes, streams and ponds. This is relatively unusual in this age of specifically targeted textbooks.

In part one, "Tools of freshwater ecological science", the first two chapters provide an excellent review of what an ecologist is, the variety of disciplines ecologists come from and a resume of the important issues of scale in ecological investigations. I would recommend the book for this alone.

We then discover the structure, chemistry and characteristics of freshwater lakes and rivers in successive readable chapters. Unlike standard freshwater textbooks, the subject is not treated systematically but introduces the student to the functioning of elements of systems under broad headings.

Part two asks questions - and partially answers them - about population numbers and dispersal, about habitat types, about recovery from disturbance and the impact of predators. This is all solid stuff.

Part three deals with environmental change, pollution and eutrophication as applied ecological problems; what happens in perturbation of environments, assessment of pollution, lake restoration and invasions by exotic species.

The invasion of the Great Lakes by zebra mussels, with consequent dramatic environmental change, is well described. This is highly pertinent to Ireland, where lakes are undergoing major change due to an invasion of this species. This is a good book, written in a way to stimulate and challenge students beginning to study limnology.

Ecology is disappointing for an international third edition. It is well written, well illustrated, and has many detailed and worked examples and website references. However, it is too slanted towards a North American readership. Students need a significant number of examples of local species, habitats and ecosystems to relate to such a complex discipline as ecology. There are many other ecology texts in a burgeoning market that fill this niche. I find this one particularly disappointing because Manuel Molles is an ecologist with experience in several countries.

First Ecology , though a second edition, is new to me. It is so readable it is almost a page-turner. Examples are drawn from around the world, and the student encounters evolution, genetics and human ecology at a very early stage. The exploration of the genes, language and distribution of indigenous American peoples is a good example, preceded by a section on human evolution. Not only is man an animal that has the potential to change our environment dramatically, we are also a species that has evolved over a relatively short period to exploit most of the planet's major ecosystems.

All the major themes are covered: species, populations, interactions, communities and systems, illustrated with up-to-date and relevant examples. The authors do not forget the history and some of the characters of the subject itself, who bring colour to science. The final chapters explore contemporary themes in the public domain. Nutrient cycles, eutrophication processes and "restoration" projects tease out the differences between natural and human influences on changing environments. Examples include conservation of the Norfolk Broads, management and restoration schemes, and oil pollution disasters from Milford Haven to Prince William Sound. Scale is dealt with from landscape ecology to biogeographical systems, and this introduces the patterns and driving variables of global climate in a change context. The final chapter deals with biodiversity and extinctions, human population growth and valuing biological resources. It is an excellent text, with good chapter outlines and reading suggestions including website material.

As is common practice in many textbooks directed at undergraduates, the exercises at the end of each chapter provide a realistic and interesting set of questions, presented with a sense of humour. The references are appropriate for an introductory text, and the glossary of technical terms is adequate and clearly defined. The diagrams and figures are generally good and clear.

I will recommend this text to my students. However, nothing is perfect. The authors should have paid more attention to the book's black-and-white photography, as the pictures are seen as through the smoke from a forest fire.

Tony Andrew is lecturer in environmental science and biology, Ulster University.