Abstract
The objective was to investigate how nitrogen allocation patterns in plants are affected by their vertical position in the vegetation (i.e. being either dominant or subordinate). A garden experiment was carried out with Amaranthus dubius L., grown from seed, in dense stands in which a size hierarchy of nearly equally aged individuals had developed. A small number of dominant plants had most of their leaf area in the highest layers of the canopy while a larger number of subordinate plants grew in the shade of their dominant neighbours. Canopy structure, vertical patterns of leaf nitrogen distribution and leaf photosynthetic characteristics were determined in both dominant and subordinate plants. The light distribution in the stands was also measured. Average N contents per unit leaf area (total canopy nitrogen divided by the total leaf area) were higher in the dominant than in the subordinate plants and this was explained by the higher average MPA (leaf dry mass per unit area) of the dominant plants. However, when expressed on a weight basis, average N contents (LNCav; total canopy N divided by the total dry weight of leaves) were higher in the subordinate plants. It is possible that these higher LNCav values reflect an imbalance between carbon and nitrogen assimilation with N uptake exceeding its metabolic requirement. Leaf N content per unit area decreased more strongly with decreasing relative photon flux density in the dominant than in the subordinate plants showing that this distribution pattern can be different for plants which occupy different positions in the light gradient in the canopy. The amount of N which is reallocated from the oldest to the younger, more illuminated leaves higher up in the vegetation may depend on the sink strength of the younger leaves for nitrogen. In the subordinate plants, constrained photosynthetic activity caused by shading might have reduced the sink intensity of these leaves.
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Anten NPR, Schieving F, Werger MJA (1995) Patterns of light and nitrogen distribution in relation to whole canopy carbon gain in C3 and C4 mono- and dicotyledonous species. Oecologia 101: 504–513
Burkey KO, Wells R (1991) Response of soybean photosynthesis and chloroplast membrane function to canopy development and mutual shading. Plant Physiol 97: 245–252
Caemmerer S von, Farquhar GD (1981) Some relationships between the biochemistry of photosynthesis and the gas exchange of leaves. Planta 153: 376–387
Crapo NL, Ketlapper HJ (1981) Metabolic properties with respect to growth and mineral uptake in roots of Hordeum, Triticum and Lycopersicon. Am J Bot 68: 10–16
Dale MP, Causton DR (1992) The ecophysiology of Veronica chamaedrys, V. montana and V. officinalis. IV. Effects of shading on nutrient allocations — a field experiment. J Ecol 80: 517–526
Evans JR (1989) Partitioning of nitrogen between and within leaves grown under different irradiances. Aust J Plant Physiol 16: 533–548
Evans JR (1993) Photosynthetic acclimation and nitrogen partitioning within a lucerne canopy. I. Canopy characteristics. Aust J Plant Physiol 20: 55–67
Field CB (1983) Allocating leaf nitrogen for the maximization of carbon gain: leaf age as a control on the allocation program. Oecologia 56: 341–347
Field CB, Mooney HA (1986) The photosynthesis nitrogen relationship in wild plants. In: Givnish TJ (ed) On the economy of plant form and function. Cambridge University Press, Cambridge, pp 25–55
Ford ED (1975) Competition and stand structure in some evenaged plant monocultures. J Ecol 63: 311–333
Hirose T, Werger MJA (1987a) Nitrogen use efficiency in instantaneous and daily photosynthesis of leaves in the canopy of a Solidago altissima stand. Physiol Plant 70: 215–222
Hirose T, Werger MJA (1987b) Maximizing daily canopy photosynthesis with respect to the leaf nitrogen allocation pattern in the canopy. Oecologia 72: 520–526
Hirose T, Werger MJA (1994) Photosynthetic capacity and nitrogen partitioning among species in the canopy of a herbaceous plant community. Oecologia 100: 203–212
Hirose T, Werger MJA, Pons TL, Rheenen JWA van (1988) Canopy structure and leaf nitrogen distribution in a stand of Lysimachia vulgaris L. as influenced by stand density. Oecologia 77: 145–150
Hirose T, Werger MJA, Rheenen JWA van (1989) Canopy development and leaf nitrogen distribution in a stand of Carex acutiformis. Ecology 70: 1610–1618
Khanna-Chopra R, Reddy PV (1988) Regulation of leaf senescence by reproductive sink intensity in cowpea (Vigna unguiculata L. Walp). Ann Bot 61: 655–658
Monsi M, Saeki T (1953) Ueber den Lichtfaktor in den Pflanzengesellschaften und seine Bedeutung für die Stoffproduktion. Jpn J Bot 14: 22–52
Pons TL, Pearcy RW (1994) Nitrogen reallocation and photosynthetic acclimation in response to partial shading in soybean plants. Physiol Plant 92: 636–644
Pons TL, Rijnberk H van, Scheurwater I, van der Werf A (1993) Importance of the gradient in photosynthetically active radiation in a vegetation stand for leaf nitrogen allocation in two monocotyledons. Oecologia 95: 416–424
Reich PB, Walters MB (1994) Photosynthesis-nitrogen relations in Amazonian tree species. II. Variation in nitrogen vis-a-vis specific leaf area influences mass and area based expressions. Oecologia 97: 73–81
Schieving F, Pons TL, Werger MJA, Hirose T (1992a) The vertical distribution of nitrogen and photosynthetic activity at different plant densities in Carex acutiformis. Plant Soil 14: 9–17
Schieving F, Werger MJA, Hirose T (1992b) Canopy structure, nitrogen distribution and whole canopy photosynthetic carbon gain in growing and flowering stands of tall herbs. Vegetatio 102: 173–181
Stoddart JL, Thomas H (1982) Leaf senescence. In: Boulter D, Parthier B (eds) Nucleic acids and proteins in plants. (Encyclopedia of plant physiology, new series, vol. 14A). Springer, Berlin, Heidelberg, New York, pp 592–636
Walters MB, Field CB (1987) Photosynthetic light acclimation in two rainforest Piper species with different ecological amplitudes. Oecologia 72: 449–456
Weiner J, Solbrig OT (1984) The meaning and measurement of size hierarchies in plant populations. Oecologia 61: 334–336
Werger MJA, Hirose T (1988) Effects of light climate and nitrogen partitioning on the canopy structure of stands of a dicotyledonous, herbaceous vegetation. In: Werger MJA, Aart PJM van, During HJ, Verhoeven JTA (eds) Plant form and vegetation structure. SPB Academic, The Hague, pp 171–181
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Anten, N.P.R., Werger, M.J.A. Canopy structure and nitrogen distribution in dominant and subordinate plants in a dense stand of Amaranthus dubius L. with a size hierarchy of individuals. Oecologia 105, 30–37 (1996). https://doi.org/10.1007/BF00328788
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DOI: https://doi.org/10.1007/BF00328788