Plant diversity affects culturable soil bacteria in experimental grasslandcommunities

Stephan, A Meyer, AH Schmid, B

A. Stephan et al., Plant diversity affects culturable soil bacteria in experimental grasslandcommunities, J ECOLOGY, 88(6), 2000, pp. 988-998

39

INGLESE

Article

Environment/Ecology

JOURNAL OF ECOLOGY

0022-0477 → ACNP

88

6

2000

988 - 998

ISI

0022-0477(200012)88:6<988:PDACSB>2.0.ZU;2-P

1 Utilization of carbon sources by culturable soil bacteria can be assessed with BIOLOG microtiter plates (contain 31 C sources). We used this techniq ue to investigate bacterial community structure at various levels of plant diversity. Plant diversity levels were replicated and we investigated the i nfluence of three plant functional groups, grasses, legumes and non-legumin ous herbs, as well as the influence of individual plant species. 2 Catabolic activity and catabolic diversity of culturable soil bacteria we re used to estimate their density (abundance) and functional diversity, res pectively. Both increased linearly with the logarithm of plant species numb er and with the number of plant functional groups in experimental grassland ecosystems. These effects may have been caused by an increased diversity a nd quantity of material and energy flows to the soil. They may also have be en mediated by increased diversity of soil microhabitats via a stimulation of the soil fauna. 3 The presence of particular plant species or functional groups in the diff erent experimental communities stimulated the activity and functional diver sity of the culturable soil bacteria in addition to their contribution via plant diversity. The legume Trifolium repens had the strongest effect and m ay be regarded as a keystone species with regard to plant-microbial interac tions in the systems studied.