Ernest Dempsey — “A lot doesn’t necessarily mean all kinds of it”, to put in simple words the findings of the latest research on plant ecology. The findings of this new groundbreaking research, as the University of California (UC) Davis news call it, tell that plant productivity in a certain habitat does not predict the diversity of plant population. This challenges the conventional position, maintained for decades, that plant productivity is a determinant of diversity.The research paper revealing this new scientific finding has been published in the reputed journal Science. Among the 58 plant ecologists contributing to the study is Louie Yang of the Department of Entomology at UC Davis. Yang tells that their research shows that productivity does not predict plant diversity in a simple or general way—an innovative approach that studied 48 diverse grassland sites in different parts of the world. Pooling together the data, Yang and his team found that plant diversity is causally related to a complex of factors that vary locally, regionally, and globally.
This new research in effect undermines the long-held humped-back model of eco-diversity that was presented by British ecologist J. Philip Grime in 1970s that directly relates the number of plant species (diversity) to biomass (productivity). In the coming years, research on factors regulating biodiversity may concentrate on factors like history of evolution and resource supply.
In a recently published paper in the journal Ecology (Vol. 92, No. 2) Stefan A. Schnitzer and his team demonstrated that soil microbes are integral determinants of the relationship between productivity and diversity in grasslands. Their research found that plant disease decreased with increase in diversity; and for the same reason, plant productivity also increased notably. Also, they found that productivity is in part directly determined by diversity (not the other way around). Given the host-specific nature of plant diseases, increasing diversity causes low incidence of disease because new plants of the same species have a lower chance to grow close together (and get the species-specific infection).
Research on plant diversity has got new emphasis after it was revealed by researchers last year that plant diversity is threatened by global warming. Life in large parts of land can therefore be threatened as a result of habitat alteration due to climatic factors more rapidly than the local species can adapt to the change. Professor Dr. Wilhelm Barthlott, co-author of the study, commented on the study’s findings saying that biodiversity is the basis of human existence and so world politicians need to pay greater attention to this issue.
