Background: Key innovations have facilitated novel niche utilization, such as the movement of the algal predecessors of land plants into terrestrial habitats where drastic fluctuations in light intensity, ultraviolet radiation and water limitation required a number of adaptations. The NDH (NADH dehydrogenase-like) complex of Viridiplantae plastids participates in adapting the photosynthetic response to environmental stress, suggesting its involvement in the transition to terrestrial habitats. Although relatively rare, the loss or pseudogenization of plastid NDH genes...

Although extensive studies demonstrate that nitrogen (N) enrichment frequently reduces plant diversity within small quadrats (0.5 –4 m2), only a few studies have evaluated N effects on biodiversity across different spatial scales. We conducted the first experimental test of the scale dependence of N effects on species richness from a 10-year N treatment (1.75- 28 g N m−2 yr−1) in a typical steppe. We used species area relationship (SAR) to analyze the scale dependence of...