There is much discussion in the media about protecting biodiversity. But does biodiversity really matter?
Canadian and Swiss researchers wanted to know if the diversity of arbuscular mycorrhizal fungi (AMF) was important to the productivity of grasslands (M.G.A. van der Heijden, J. N. Klironomos, M. Ursic, P. Moutoglis, R. Streitwolf-Engel, T. Boler, A. Wiemken, and I. R. Sanders. 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability, and productivity. Nature 396:69-72). Specifically, they wanted to know if it mattered which specific AMF species were present, or just that some type of AMF was present. They grew various plants in combination with one of four AMF species (A, B, C, and D), no AMF species (O), or all four AMF species together (A + B + C + D); and they measured plant growth under each set of conditions. All plant species were grown in each plot, so they always competed with each other, with the only difference being which AMF species were present.
On the graphs, the x-axis labels indicate the number and identity of AMF species (bar 0 = no fungi; bars A - D = individual AMF species; bar A + B + C + D = all AMF species together). The y-axis indicates the amount (grams) of plant biomass for the species shown in italics above each graph

Examine all four graphs and choose the plant species that grows best with a combination of AMF species.
A) Carex flacca (graph a)
B) Lotus corniculatus (graph b)
C) Sanguisorba officinalis (graph c)
D) Centaurium erythrea (graph d)

Question

There is much discussion in the media about protecting biodiversity. But does biodiversity really matter?
Canadian and Swiss researchers wanted to know if the diversity of arbuscular mycorrhizal fungi (AMF) was important to the productivity of grasslands (M.G.A. van der Heijden, J. N. Klironomos, M. Ursic, P. Moutoglis, R. Streitwolf-Engel, T. Boler, A. Wiemken, and I. R. Sanders. 1998. Mycorrhizal fungal diversity determines plant biodiversity, ecosystem variability, and productivity. Nature 396:69-72). Specifically, they wanted to know if it mattered which specific AMF species were present, or just that some type of AMF was present. They grew various plants in combination with one of four AMF species (A, B, C, and D), no AMF species (O), or all four AMF species together (A + B + C + D); and they measured plant growth under each set of conditions. All plant species were grown in each plot, so they always competed with each other, with the only difference being which AMF species were present.
On the graphs, the x-axis labels indicate the number and identity of AMF species (bar 0 = no fungi; bars A - D = individual AMF species; bar A + B + C + D = all AMF species together). The y-axis indicates the amount (grams) of plant biomass for the species shown in italics above each graph

Examine all four graphs and choose the plant species that grows best with a combination of AMF species.
A) Carex flacca (graph a) 
B) Lotus corniculatus (graph b) 
C) Sanguisorba officinalis (graph c) 
D) Centaurium erythrea (graph d)

Quizplus · Accepted Answer

In graph b, the plant species Lotus corniculatus shows the greatest increase in biomass when grown with all four AMF species together (A + B + C + D) compared to when no AMF species are present (bar 0). This suggests that the specific combination of AMF species is important for the growth and productivity of this plant species, and therefore biodiversity of AMF species may be important for ecosystem productivity.

There Is Much Discussion in the Media About Protecting Biodiversity