To test how predicted increases in rainfall variability migh

To test how predicted increases in rainfall variability might affect a temperate grassland ecosystem, researchers set up the following experiment: over a 4-year period, control plots received normal rainfall. Experimental plots received the same overall amount of precipitation, but delivered in fewer rain events separated by longer dry spells. They measured aboveground biomass (an index of NPP; P- 0.039) and plant species diversity (P 0.05) S 1.8 700 600 1.6 & 500 1.4 400 1.2 e 300 200 1.0 Control Experimental Control Experimental plots plots plots plots

Solution

As compared to the control, the experimental species experienced higher species diversity. Higher species diversity implies that there is more sustainability of more kinds of species . Thus , the answer to the question would be reduced competition by the dominant species.

If the competition by the dominant species would have been high, the increase on an average of species richness would not have been seen. The increase or decrease of predation does not necessarily impact on the species diversity. Only If the selection pressure by dominant species is less leading to less competition, there can be a greater variety of species.