Fræðaþing landbúnaðarins - 16.02.2007, Side 19

17 • Fræðaþing landbúnaðarins 4, 2007
Conclusions
Functional equation models are a new tool to gain íurther insight into intraspecific
variability in the response to elevated C02 as fare as this variability is related to a
functional response hypothesis. Knowledge on the significance of elevated C02 as a
selecting force may be gained by comparing populations from sites at which C02 had
been increased during the last decades (natural C02 springs) with populations from
sites with ambient C02 but otherwise comparable environmental conditions or from
experimental populations grown for years under ambient or elevated C02.
References
Ainsworth, E.A., P.A. Davey, G.J. Hymus, C.P. Osbome, A. Rogers, H. Blum, J. Nösberger & S.P. Long
(2003). Is stimulation of leaf photosynthesis by elevated carbon dioxide concentration maintained in the
long term? A test with Lolium perenne grown for 10 years at two nitrogen fertilization levels under Free Air
C02 Enrichment (FACE). Plant, Cell and Environment, 26, 705-714.
Allard, V., P.C.D. Newton, J.F. Soussana, R.A. Carran & C. Matthew (2003). Increased quantity and quality
of coarse soil organic matter fractions at elevated C02 in a grazed grassland are a consequence of enhanced
root growth and turnover. Plant and Soil, 276, 49-60.
Almeida, J.P.F., A. Liischer, M. Frehner, A. Oberson & J. Nösberger (1999). Partitioning of P and the activ-
ity of root acid phosphatase in white clover (Trifolium repens L.) are modified by increased atmospheric
C02 and P fertilisation. Plant and Soil, 210, 159-166.
Bazzaz, F.A. & K. Garbutt (1988). The response of annuals in competitive neighbourhoods: effects of el-
evated C02. Ecology, 69, 937-946.
Bradshow, A.D. & T. McNeilly (1991). Evolutionary response to global climatic change. Annals of Botany,
67, 5-14.
Campbell, B.D., D.M. Stafford Smith, J. Ash, J. Fuhrer, R.M. Gifford, P. Hiemaux, S.M. Howden, M.B.
Jones, J.A, Ludwig, R. Manderscheid, J.A. Morgan, P.C.D. Newton, J. Nösberger, C.E. Owensby, J.F.
Soussana, Z. Tuba & C. ZuoZhong (2000). A synthesis of recent global change research on pasture and
rangeland production: reduced uncertainties and their management implications. Agriculture, Ecosystems
and Environment, 82, 39-55.
Curtis, P.S., A. Snow & A.S. Miller (1994). Genotype-specific effects of elevated C02, on fecundity in wild
radish (Raphanus raphanistmm). Oegologia, 97, 100-105.
Daepp, M., D. Suter, J.P.F. Almeida, H. Isopp, U.A. Hartwig, M. Frehner, H. Blum, J. Nösberger & A.
Liischer (2000). Yield response of Lolium perenne swards to free air C02 enrichment increased over six
years in a high-N-input system on fertile soil. Global Change Biology, 6, 805-816.
Daepp, M., J. Nösberger & A. Ltischer (2001). Nitrogen fertilisation and developmental stage affect the
response of yield, biomass partitioning and morphology of Lolium perenne L. swards to elevated pC02.
New Phytologist, 150, 347-358.
Drake, B.G., M.A. González-Meler & S.P. Long (1997). More efficient plants: a consequence of rising
atmospheric C02? Annual Review of Plant Physiology and Plant Molecular Biology, 48, 609-639.
Edwards, G.R., H. Clark & P.C.D Newton (2001). The effects of elevated C02 on seed production and
seedling recruitment in a sheep-grazed pasture. Oecologia, 127, 383-394.
Expert, J.M., P. Jacquard, M. Obaton & A. Luscher (1997). Neighbourhood effect of genotypes of Rhizo-
bium leguminosarum biovar trifolii, Trifolium repens and Lolium perenne. Theoretical and Applied Genet-
ics, 94,486-492.