When closely related plant species occur in the same region, their distributions at small spatial scales are expected to depend on whether they have evolved different tolerances to variation in the environment. Whether species can coexist in the long term should depend on differences in their ability to compete for resources. In a recent article published in AoB PLANTS, Eckhart et al. report that two closely related annual plants differ in distribution, performance, and competitive abilities as functions of soil-texture (i.e., particle-size) variation. The influence of soil texture on plant distributions and the structure of ecological communities may be underappreciated.
Eckhart, V. M., Howland, M. R., Jennison, K., Kircher, B. K., Montgomery, D. M., Yuan, Y., & Geber, M. A. (2017). Contrasting soil-texture niches facilitate coexistence of two congeneric plants that differ in competitive ability. AoB PLANTS, 9(6). http://dx.doi.org/10.1093/aobpla/plx066