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Gr 7 Up—Grouping topics around five biomes (marine/oceanic, inland aquatic, desert, forest, and grassland/tundra/human), this set offers 35 signed overviews on subtopics relevant to the various areas, and 500 two- to four-page signed essays on specific locations or ecosystems such as the Everglades, the Kalahari Desert, or the Mid-Pacific Gyre (the "Trash Vortex," where mostly plastic debris is trapped by circular oceanic currents)...