Seasonal variations in photosynthesis, intrinsic water-use efficiency and stable isotope composition of poplar leaves in a short-rotation plantation
| Autor: | L.S. Broeckx, Régis Fichot, M.S. Verlinden, Reinhart Ceulemans |
|---|---|
| Přispěvatelé: | Department of Biology, Research Group of Plant and Vegetation Ecology, University of Antwerp (UA), Laboratoire de Biologie des Ligneux et des Grandes Cultures (LBLGC), Institut National de la Recherche Agronomique (INRA)-Université d'Orléans (UO) |
| Rok vydání: | 2014 |
| Předmět: |
Stomatal conductance
Genotype Physiology [SDV]Life Sciences [q-bio] mesophyll conductance Growing season Plant Science Oxygen Isotopes Biology Carbon sequestration Photosynthesis Belgium Water-use efficiency 2. Zero hunger Carbon Isotopes leaf nitrogen Stable isotope ratio Water Forestry 15. Life on land Research Papers Photosynthetic capacity Plant Leaves Populus Agronomy stomatal conductance Soil water short-rotation-coppice soil water deficit photosynthetic nitrogen-use efficiency Seasons maximum rate of carboxylation |
| Zdroj: | Tree Physiology Tree Physiology, Oxford University Press (OUP): Policy B-Oxford Open Option B, 2014, 34 (7), pp.701-15. ⟨10.1093/treephys/tpu057⟩ Tree physiology |
| ISSN: | 1758-4469 0829-318X |
| DOI: | 10.1093/treephys/tpu057 |
| Popis: | Photosynthetic carbon assimilation and transpirational water loss play an important role in the yield and the carbon sequestration potential of bioenergy-devoted cultures of fast-growing trees. For six poplar (Populus) genotypes in a short-rotation plantation, we observed significant seasonal and genotypic variation in photosynthetic parameters, intrinsic water-use efficiency (WUEi) and leaf stable isotope composition (delta C-13 and delta O-18). The poplars maintained high photosynthetic rates (between 17.8 and 26.9 mu mol m(-2) s(-1) depending on genotypes) until late in the season, in line with their fast-growth habit. Seasonal fluctuations were mainly explained by variations in soil water availability and by stomatal limitation upon photosynthesis. Stomatal rather than biochemical limitation was confirmed by the constant intrinsic photosynthetic capacity (V-cmax) during the growing season, closely related to leaf nitrogen (N) content. Intrinsic water-use efficiency scaled negatively with carbon isotope discrimination (Delta C-13(bl)) and positively with the ratio between mesophyll diffusion conductance (g(m)) and stomatal conductance. The WUEi - Delta(13)Cbl relationship was partly influenced by g(m). There was a trade-off between WUEi and photosynthetic N-use efficiency, but only when soil water availability was limiting. Our results suggest that seasonal fluctuations in relation to soil water availability should be accounted for in future modelling studies assessing the carbon sequestration potential and the water-use efficiency of woody energy crops. |
| Databáze: | OpenAIRE |
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