BIODEPTH
Biodiversity and ecosystem processes in terrestrial herbaceous ecosystems (EU Environmental Programme)
Supported by: EEC Environment Programme, Az.: ENV4-CT95-0008
Project homepage: external link Biodiversity Programme (BIODEPTH) implemented under the Fourth Framework Programme (1994-1998) (external link)
Coordinators: The project is coordinated and administered by Prof. John H. Lawton, NERC Centre of Population Biology, Imperial College at Silwood Park, Ascot, Berkshire, UK SL5 7PY
Responsible scientists at MPI-BGC: Prof. Dr. E.-D. Schulze (former Department of Plantecology, Univ. Bayreuth)
Prof. Dr. C. Beierkuhnlein (Department of Biogeography, Univ. Bayreuth)
Responsible students: Michael Scherer
Alexandra Prinz (Department of Biogeography, Univ. Bayreuth)
Clemens Rometsch (1998)
Jens Reinhard (1998)
Barbara Dippold (1997)
Friedhelm Keil (1996)
Sheena Sloan (1996)
Suzanne Le Mière (1996)
Duration: 3 years (1996-1999)
Rationale and objectives
BIODEPTH (Biodiversity and Ecological Processes in Terrestrial Herbaceous Ecosystems) is an EEC Programme as part of the Terrestrial Ecosystem Research Initiative (TERI) (external link), coordinated by Prof. Dr. J.H.Lawton, Imperial College at Silwood Park, UK.

Within BIODEPTH, a network of European experimental grassland communities was established that mimics loss of biodiversity by creating replicate plant communities with reduced species richness. On each site, effects of reduced biodiversity on key ecosystem processes and structural characteristics were determined and quantified. At the German site (Bayreuth), we focused on effects on productivity, nutrient cycling, soil nitrate leaching, decomposition, canopy architecture, competition and population biology of species involved. The experimental manipulation of plant species diversity significantly changed the dynamics of those ecosystem processes. For example, productivity decreased linearly with decreasing species richness. Concentrations of soil water nitrate were higher than the European official limit for drinking water under situations of low diversity. The results obtained during the three-year-period of the project support our hypothesis that biodiversity affects ecosystem functioning and population dynamics. Functional characteristics of plant species - especially the ability to fix nitrogen - play a major role for several ecosystem processes and are at least as important as their number per se. Resource-use complementarity in more diverse systems could explain the higher productivity and lower nitrogen losses.

The project anticipates
  • to establish a network of European field sites in natural and semi-natural plant communities along a NW to SE (Ireland to Greece) and a NE to SW (Sweden to Portugal) gradient through Europe,
  • to establish a common experiment that mimics world - and European-wide loss of biodiversity,
  • to determine and quantify the effects of reduced biodiversity on key ecosystem processes and structural characteristics at each site,
  • to clarify the role of plant ecological diversity in maintaining ecosystem processes,
  • to develop theoretical models linking biodiversity, functional groups, population biology and ecosystem processes,
  • to establish the rates at which depauperate communities are reinvaded by experimentally excluded species, and/or the rate at which species are lost from more diverse communities,
  • to improve the capacity of ecologists to predict the consequences of loss of biodiversity for ecosystem processes from local to landscape-level scale
The MPI-BGC / Bayreuth group will
  • study population biology, plant competition and key ecosystem processes in natural grassland communities of different diversity which resulted from land management,
  • establish a biodiversity field experiment with the following design.
Design of the MPI-BGC / Bayreuth group
The planned experiment contains 3 components
1. Diversity Experiment: Plantation of an experimental field with variable diversity.
2. Density Experiment: Plantation of plots with variable density.
3. Species competition: nearest neighbor analysis of key species in existing communities.
1. Diversity experiment:
The selection of the species is based on two steps:
  • i. subjective selection of 31 species from the local flora (seed availability, germination rate etc.).
  • ii. random allocation of these species to the diversity treatments within certain constraints (proportions of grasses, legumes and herbs, semi-nested design for comparing the ten monoculture-species in all diversity treatments).
Monocultures: 1. Alopecurus pratensis
2. Arrhenatherum elatius
3. Dactylis glomerata
4. Festuca rubra
5. Holcus lanatus
6. Trifolium pratense
7. Trifolium repens
8. Geranium pratense
9. Plantago lanceolata
10. Ranunculus acris
2-species mixtures: 1. Alopecurus pratensis + Arrhenatherum elatius
2. Festuca rubra + Holcus lanatus
3. Dactylis glomerata + Trifolium repens
4. Festuca rubra + Trifolium pratense
5. Arrhenatherum elatius + Geranium pratense
6. Festuca rubra + Plantago lanceolata
7. Festuca pratensis + Ranunculus acris
4-species mixtures: 1. Arrhenatherum elatius + Dactylis glomerata + Holcus lanatus + Lolium perenne
2. Alopecurus pratensis + Arrhenatherum elatius + Festuca rubra + Trifolium repens
3. Alopecurus pratensis + Dactylis glomerata + Holcus lanatus + Geranium pratense
4. Alopecurus pratensis + Arrhenatherum elatius + Lotus corniculatus + Plantago lanceolata
5. Festuca rubra + Lolium perenne + Trifolium pratense + Ranunculus acris
8-species mixtures: 1. Alopecurus pratensis + Arrhenatherum elatius + Dactylis glomerata + Festuca pratensis + Festuca rubra + Holcus lanatus + Lolium perenne + Phleum pratense
2. Arrhenatherum elatius + Dactylis glomerata + Festuca rubra + Holcus lanatus + Lolium perenne + Phleum pratense +Trifolium pratense + Trifolium repens
3. Alopecurus pratensis + Arrhenatherum elatius + Dactylis glomerata + Holcus lanatus + Lolium perenne + Achillea millefolium + Geranium pratense + Ranunculus acris
4. Alopecurus pratensis + Arrhenatherum elatius + Festuca pratensis + Festuca rubra + Lathyrus pratensis + Trifolium pratense +Rumex acetosa + Taraxacum officinale
5. Anthoxanthum odoratum + Cynosurus cristatus + Festuca pratensis + Lolium perenne + Lotus corniculatus + Vicia sepium + Crepis biennis + Leontodon autumnalis
16-species mixtures: 1. Alopecurus pratensis + Anthoxanthum odoratum + Cynosurus cristatus + Dactylis glomerata + Festuca pratensis + Festuca rubra + Lolium perenne + Phleum pratense + Lathyrus pratensis + Trifolium pratense + Vicia cracca + Vicia sepium + Geranium pratense + Leontodon autumnalis + Ranunculus acris + Lychnis flos-cuculi
2. Arrhenatherum elatius + Anthoxanthum odoratum + Bromus mollis + Cynosurus cristatus + Dactylis glomerata + Holcus lanatus + Lolium perenne + Phleum pratense + Lotus corniculatus + Trifolium pratense + Vicia cracca + Vicia sepium + Achillea millefolium + Campanula patula + Crepis biennis + Chrysanthemum leucanthemum
3. Alopecurus pratensis + Anthoxanthum odoratum + Arrhenatherum elatius + Bromus mollis + Festuca rubra + Holcus lanatus + Lolium perenne + Phleum pratense + Lotus corniculatus + Trifolium pratense + Trifolium repens + Vicia cracca + Pimpinella major + Centaurea jacea + Knautia arvensis + Plantago lanceolata
2. Density Experiment:
Species: Dactylis glomerata, Plantago lanceolata and Trifolium pratense
Following treatments are planned:
  • change of the density pattern: 1 seed per 10 cm2, 5 cm2, 1 cm2 in monoculture,
  • change of composition at different densities: 2 and 3 species,
  • change in mixing ratios of 2 to 3 species,
3. Species competition:
A nearest neighbour analysis will be carried out for those species which are used in monoculture in the Diversity Experiment, based on observations in existing grassland communities.
Publications
Thesis Michael Scherer (PhD 1999) Clemens Rometsch (Diploma 1998) Jens Reinhard (Diploma 1998) Barbara Dippold (Diploma 1997) Friedhelm Keil (Diploma 1996) Sheena Sloan (Diploma 1996) Suzanne Le Mière (Diploma 1996)

Schulze E-D, Mooney HA (eds.) Ecosystem Function of Biodiversity. Ecological Studies 99, 525 pp, 1993

Mooney HA, Cushman JH, Medina E, Sala OE, Schulze E-D (1996) What have we learned about the ecosystem functioning of biodiversity. In: HA Mooney, JH Cushman, E Medina, OE Sala, E-D Schulze (eds.) Functional Roles of biodiversity: A global perspective. John Wiley, SCOPE Series 55:475-484.

Schulze E-D, Bazzaz FA, Nadelhoffer K, Koike T, Takatsuki S (1996) Biodiversity and ecosystem function of temperate deciduous broad-leaved forests. In: HA Mooney, JH Cushman, E Medina, OE Sala, E-D Schulze (eds.) Functional Roles of biodiversity: A global perspective. John Wiley, SCOPE Series 55:71-98.

Mooney HA, Cushman JH, Medina E, Sala OE, Schulze E-D (1996) The SCOPE Ecosystem functioning of Biodiversity program. In: HA Mooney, JH Cushman, E Medina, OE Sala, E-D Schulze (eds.) Functional Roles of biodiversity: A global perspective. John Wiley, SCOPE Series 55:1-7.

Schulze E-D (1995) Flux control at the ecosystem level. TREE 10: 40-43

Schulze E-D, Mooney HA (1993) Ecosystem Function of Biodiversity: A Summary. Ecological Studies 99: 497 - 510

Schulze E-D, Gerstberger P (1993) Functional aspects of landscape biodiversity: A Bavarian example. Ecological Studies 99: 453-469

Chapin FS III, Schulze E-D, Mooney HA (1992) Biodiversity and ecosystem processes. TREE 7:107-108.