THE GLOBAL DISTRIBUTION OF NET PRIMARY PRODUCTION CLOSELY MATCHES THE DISTRIBUTION OF EARTH’S CLIMATIC ZONES AND BIOMES
FIGURE 7.1 Primary production is highest in equatorial regions where the natural vegetation is tropical forest. Temperate forest regions support the next highest levels of primary production. Meanwhile, the lowest rates of primary production occur in the cold dry tundra and in deserts, which may be cold or hot but are always dry. Between these end members are boreal forests, temperate grasslands, and savannas, which support medium levels of primary production. (After Del Grosso et al., 2008)