Image courtesy of gbaku
We needn't tell you of the many benefits and services plants - especially trees - offer. So it shouldn't come as much of a surprise that the mass extinction of plants, more so than that of animal species, can and will have disproportionate implications for the planet's ecosystems. Indeed, a new study published in the Proceedings of the National Academy of Science has indicated that an extinction could cut global productivity levels by as much as 50%.
Bradley Cardinale, an ecologist at the University of California Santa Barbara, conducted a meta-analysis of 44 experiments and played around with the number of species in different plant communities to simulate the effect of a mass extinction. In each case, he and his colleagues compared the biomass produced in the most diverse assemblage with the least diverse, typically a monoculture (go figure). The effect, an average decrease in productivity of 50%, was seen to accelerate over time, though Cardinale cautions not to overstate the results: "Because research generally is funded for short time periods, it's difficult to assess how long it takes to reach the maximum impact of diversity loss, but clearly we've underestimated the effects."
The critical take-home message, he emphasizes, is that the conversion of large regions around the world to monocultures may be doing us much more harm than we previously realized: "[I]t behooves us to understand we may be compromising nature's capacity to provide ecological services critical to humanity."
Regrettably, we can't say we find that conclusion surprising. It's long been known that drastically reducing an ecosystem's plant diversity can have disastrous consequences for its normal functioning. Perhaps the only really surprising aspect of this study is the fact that dominant species play a much less important role in maintaining the system's productivity than previously thought.
Via ::Environmental Science & Technology: Plant extinctions could cut ecosystem productivity in half (scientific journal)