Leaf Phenology and Seasonal Carbon Gain in the Invasive Plant, Bunias orientalis L.

Abstract

In two potentially competing herbaceous plants, the invasive Bunias orientalis L. (Brassicaceae) and the native Picris hieracioides L. (Asteraceae), seasonal changes in leaf CO₂ gas exchange and plant growth were studied over an entire growing season from February 1998 to December 1998 in two experimental fields. The study was motivated by the hypothesis that pre-adaptive phenological displacement of alien species relative to the native flora may be an important reason for the observed expansion of B. orientalis in central Europe. We quantified the importance of phenological differences for annual carbon gain in both species by estimating total leaf carbon gain from the results of leaf CO₂ exchange and changes in plant leaf area. Bunias orientalis achieved almost half of its annual carbon gain in the time between early September and December, when competition for light by other species, like P. hieracioides, is low. Our quantitative approach corroborates the notion that the phenological shift of a relatively poor competitor, such as B. orientalis, could be of great importance for the success as an invasive species.

Key words

Carbon budgets - invasive plants - leaf phenology - net photosynthesis - seasonal carbon budget - scaling

References

• 01 Bazzaz,  F. A.. (1986) Life history of colonizing plants: some demographic, genetic, and physiological features. Ecology of biological invasions of North America and Hawaii. Mooney, H. A. and Drake, J. A., eds. New York; Springer pp. 96-110
• 02 Beyschlag,  W.,, Lange,  O. L.,, and Tenhunen,  J. D.. (1987);  Photosynthese und Wasserhaushalt der immergrünen mediterranen Hartlaubpflanze Arbutus unedo L. im Jahreslauf am Freilandstandort in Portugal. II. Charakteristische Gaswechselparameter von CO₂-Aufnahme und Transpiration.  Flora. 179 399-420
• 03 Crawley,  M. J.. (1987) What makes a community invasible?. Colonization, succession and stability. Gray, A. J., Crawley, M. J., and Edwards, P. J., eds. Oxford; Blackwell Scientific pp. 429-453
• 04 Dietz,  H., and Steinlein,  T.. (1996);  Determination of plant species cover by means of image analysis.  Journal of Vegetation Science. 7 131-136
• 05 Dietz,  H.,, Steinlein,  T.,, and Ullmann,  I.. (1998);  The role of growth form and correlated traits in competitive ranking of six perennial ruderal plant species grown in unbalanced mixtures.  Acta Oecologica. 19 25-36
• 06 Dietz,  H.,, Steinlein,  T.,, and Ullmann,  I.. (1999);  Establishment of the invasive perennial herb Bunias orientalis L.: an experimental approach.  Acta Oecologica. 20 621-632
• 07 Dietz,  H., and Ullmann,  I.. (1997);  Phenological shifts in the alien colonizer Bunias orientalis: image-based analysis of temporal niche seperation.  Journal of Vegetation Science. 8 839-846
• 08 Field,  C., and Mooney,  H. A.. (1986) The photosynthesis-nitrogen relationship in wild plants. On the Economy of Plant Form and Function. Givnish, T. J., ed. Cambridge; Cambridge University Press pp. 25-55
• 09 Klemov,  K. M., and Raynal,  D. J.. (1985);  Demography of two facultative biennial plant species in an unproductive habitat.  Journal of Ecology. 73 147-167
• 10 Lodge,  D.. (1993);  Biological invasions: Lessons for ecology.  Trends in Ecology and Evolution. 8 133-137
• 11 Noble,  I. R.. (1989) Attributes of invaders and the invading process: terrestrial and vascular plants. Biological invasions: a global perspective. Drake, J. A., Mooney, H. A., Di Castri, F., Groves, R. H., Kruger, F. J., Rejmanek, M., and Williamson, M., eds. Chicester; John Wiley & Sons pp. 301-313
• 12 Roy,  J.. (1990) In search of the characteristics of plant colonizers. Biological invasions in Europe and the Mediterranean basin. Di Castri, F., Hansen, A., and Debussche, M., eds. Dordrecht; Kluwer Academic Publishers pp. 335-352
• 13 Steinlein,  T.,, Dietz,  H.,, and Ullmann,  I.. (1996);  Growth patterns of Bunias orientalis (Brassicaceae) underlying its rising dominance in some native plant assemblages.  Vegetatio. 125 73-82
• 14 Tichá,  I.,, Catsky,  F.,, Hodánová,  D.,, Pospísilová,  F.,, and Sesták,  Z.. (1985) Gas exchange and dry matter accumulation during leaf development. Photosynthesis during leaf development. Sesták, Z., ed. Dordrecht; Junk Publisher pp. 157-216
• 15 Tutin,  T. G.,, Heywood,  V. H.,, Burges,  N. A.,, Moore,  D. M.,, Valentine,  D.,, Walters,  S. M.,, and Webb,  D. A.. (1993) Flora Europaea. Cambridge; Cambridge University Press
• 16 Von Caemmerer,  S., and Farquhar,  G. D.. (1981);  Some relationships between the biochemistry of photosynthesis and the gas exchange of leaves.  Planta. 153 376-387
• 17 Zotz,  G.. (1997);  Photosynthetic capacity increases with plant size.  Botanica Acta. 110 306-308
• 18 Zotz,  G.,, Büdel,  B.,, Meyer,  A.,, Zellner,  H.,, and Lange,  O. L.. (1997);  Water relations and CO₂ exchange of tropical bryophytes in a lower montane rainforest in Panama.  Botanica Acta. 110 9-17
• 19 Zotz,  G., and Winter,  K.. (1993);  Short-term photosynthesis measurements predict leaf carbon balance in tropical rainforest canopy plants.  Planta. 191 409-412
• 20 Zotz,  G., and Winter,  K.. (1994);  Predicting annual carbon balance from leaf nitrogen.  Naturwissenschaften. 81 449
• 21 Zotz,  G., and Winter,  K.. (1996 a) Diel patterns of CO₂ exchange in rainforest canopy plants. Tropical Forest Plant Ecophysiology. Mulkey, S. S., Chazdon, R. L., and Smith, A. P., eds. New York; Chapman & Hall pp. 89-113
• 22 Zotz,  G., and Winter,  K.. (1996 b) Seasonal changes in daytime versus nighttime CO₂ fixation of Clusia uvitana in situ. . Crassulacean acid metabolism. Biochemistry, ecophysiology and evolution. Winter, K. and Smith, J. A. C., eds. Berlin; Springer pp. 312-323

Section Editor: R. Aerts