The effect of species loss on ecosystem productivity is determined by both the functional contribution of the species lost, and the response of the remaining species in the community. According to the mass-ratio hypothesis, the loss of a dominant plant species, which has a larger proportionate contribution to productivity, is expected to exert an overwhelming effect on this important ecosystem function. However, via competitive release, loss of a dominant species can provide the opportunity for other plant species to establish, thrive and become abundant in the community, potentially compensating for the function lost. Furthermore, if resource limitation is removed, then compensatory response of function to the loss of a dominant species should be greater and more rapid than if resources are more limiting.

To evaluate how resources may limit compensation of aboveground productivity to the loss of a dominant plant species, we experimentally removed the C₄ perennial tallgrass, Andropogon gerardii, from intact plant communities. We added water for four years, as well as nitrogen in the fourth year, to test the effect of resource limitation on the compensatory response.

Overall, aboveground biomass production increased in the remaining community with both water and nitrogen addition. However, this increase in biomass production was not sufficient to fully compensate for the loss of A. gerardii, indicating water and nitrogen were not limiting short-term compensation in this community.

Following the removal of the dominant species, there was a reordering of species abundances in the community, rather than changes in species richness. The C₄ grass Bouteloua curtipendula was the most responsive species, increasing by 57.9% in abundance with water addition and 91.0% with both water and nitrogen addition. Despite this dramatic increase in abundance, its short stature and lower per capita biomass production prevented this species from compensating for the loss of A. gerardii.

Our results suggest that short-term compensation after the loss of a dominant plant species can be hastened by increased resource availability, but ultimately full compensation appears to be limited by the presence and abundance of species in the remaining community that possess traits that allow them compensate for the species lost.

Data collected from a removal experiment of a dominant species to evaluate the aboveground biomass response of the remaining community in a native tallgrass prairie.
The data was collected during four growing seasons from 2013 to 2016.
Total number of stems were counted for each species within each plot in the spring at the beginning of the growing season and in the fall during the preoces of biomass collection.
Biomass data was collected from tillers clipped at the end of the growing season, sorted by species, dried for 48h at 60°C and weighed to the closest 0.01g for typical samples, and to the closest 0.0001g for very small samples.
Biomass per square meter was calculated by extrapolating the biomass per plot (0.25m2) to 1m2.

NA entries correspond to missing values of biomass due to missing samples.

A readme file contains a metadata with an explanation of the variables in the dataset.  NA entries correspond to missing values of biomass due to missing samples. Detailled information on how the data was collected can be found in the associated manuscript referenced above.