A photo-illustrated, older elementary/middle science book, published by Houghton Mifflin as part of their “Scientists in the Field” series.  Available in paperback as well.

Middle Grade Nonfiction Book

Middle school students can learn the ecology of each continent in depth with this series of books: Africa, Antarctica, Asia, Australia, Europe, North America, and South America.

Africa . . . . . . . . . . . . . . . . . ISBN 0-7613-1367-2
Antarctica. . . . . . . . . . . . . . ISBN 0-7613-3227-8
Asia. . . . . . . . . . . . . . . . . . . ISBN 0-7613-1368-0
Australia. . . . . . . . . . . . . . . ISBN 0-7613-3007-0
Europe . . . . . . . . . . . . . . . . ISBN 0-7613-3008-9
North America . . . . . . . . . . ISBN 0-7613-3226-X
South America . . . . . . . . . . ISBN 0-7613-1366-4

A middle grade nonfiction book about field scientists and how they study animals.

A middle grade nonfiction book published by Twenty-First Century Books. Part of the Scientific American Sourcebooks Series.

Desert. . . . . . . . . . . . . . . . . ISBN 0-8050-2825-0
Temperate Deciduous 
Forest. . . . . . . . . . . . . . . . . ISBN 0-8050-2828-5
Tropical Rain Forest . . . . . ISBN 0-8050-2826-9
Coral Reef . . . . . . . . . . . . . ISBN 0-8050-4087-0
River and Stream  . . . . . . . ISBN 0-8050-4088-9
Wetland . . . . . . . . . . . . . . . ISBN 0-8050-4086-2
Ocean. . . . . . . . . . . . . . . . . ISBN 0-8050-4086-2
Seashore. . . . . . . . . . . . . . . ISBN 0-8050-4085-4
Tundra . . . . . . . . . . . . . . . . ISBN 0-8050-2829-3
Taiga . . . . . . . . . . . . . . . . . ISBN 0-8050-2830-7
Lake and Pond. . . . . . . . . . ISBN 0-8050-4089-7
Grassland. . . . . . . . . . . . . . ISBN 0-8050-2827-7