Gr 6-8 "When healthy, the Gulf floor teems with many kinds of life, but in a dead zone, it is covered with grayish-black, foul-smelling goo." Highlighting one of the more insidious by-products of environmental pollution, Hand explains how fertilizer runoff can result in algal blooms far downstream that leave huge areas of fresh or salt water so hypoxicor low in oxygenthat only anaerobic bacteria can survive. Though noting that the Baltic contains seven of the world's 10 largest "dead zones," she focuses mainly on the Gulf of Mexico, where problems caused by such runoff (exacerbated both by local oil spills and by federal programs that encourage Midwestern farmers to grow more corn to convert to ethanol) have sharply affected the fishing and shrimp industries. While the author examines some successful reclamation effortsnotably Boston Harbor and on a larger scale the Black Seashe doesn't point to simple or easy remedies for this growing blight, either. The cramped photos and maps, along with the narrative's tiny type size, give this study a utilitarian look, but the book covers a worrisome topic in more detail than readers will find elsewhere and also offers generous quantities of print and web resources for further research. VERDICT A significant overview for serious eco-activists or any students interested in our planet's oceans and waterways. John Peters, Children's Literature Consultant, New York City

Emphasizing the interconnectedness of global ecosystems, Hand dives into the growing problem of dead zones: vast regions of earth's oceans that suffer from decreased oxygen levels, which devastate marine plant and animal populations. She clearly explains how dead zones arise rtilizer washes into the ocean, propagating algal blooms, which overwhelm the ecosystem with decaying plant matter and bacteria, which in turn consume the water's available oxygen fore getting into the causes of the problem. Large-scale agriculture, climate change, and increased levels of carbon dioxide in the atmosphere are all major culprits. Occasionally Hand's use of statistics overshadows her salient points, but her discussion of both the effects of dead zones and the counterintuitive efforts of government and conservation organizations effectively communicates how complicated and wide-ranging an issue this is. Maps and diagrams helpfully illustrate some of the science, and the straightforward, unsparing text will encourage students to think critically about their own choices, even if they live far away from the ocean. An illuminating introduction to a complicated, dire ecological problem that deserves more attention.