The ARC LTER uses plastic-covered greenhouses, shade frames, and fertilizer addition in long-term manipulations of tundra ecosystems. Effects of N fertilizers are shown in the middle ground of this photo, where the vegetation is taller, denser, more productive, less species rich, and dominated by the deciduous dwarf shrub Betula nana.

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© Copyright 2015 LTER. MSC03 2020, 1 University of New Mexico, Albuquerque, NM, USA 87131.